COVER STORY

Knowledge Park, Hyderabad

Knowledge Park design is conceived to be a new age IT campus in Hi-Tech City, Hyderabad. It is futuristic and portrays as a destination by its own. It is spread across 10 Acres of land.

Total built-up area is of 5-Million Sq. ft comprising of two-towers, one having 30-levels and the other of 26-levels. Knowledge Park is IGBC Platinum Certified Green Building. Entire project right from the foundation / basements to the super structure is designed and being executed as a Composite steel structure.

Thought Process
There has been a growing interest in Hyderabad as an IT destination. The demand for business space for IT and financial sectors on built-to-suit and ready to build basis is also increasing constantly.

Keeping in view all the points, a was building to provide office infrastructure and business support for computer software companies, working in the electronics, telecommunications, engineering, and finance sectors.

As the site is located in Hi-Tech city of Hyderabad and the site profile being triangular in shape, having different levels of roads on all 3 sides, RSP Consultants who could do justice in dealing with such complex site by proper planning, best utilization of site contours and who could create a futuristic iconic structure were selected. Also, they had the requisite experience in dealing with commercial IT projects.

The designers were told to utilize the road levels on all 3 sides well, by giving multiple entry /exits for easy flow of traffic within the campus and outside the campus. A brief was also given to design efficient workspaces with proper light and good ventilation.

The architects were instructed to provide shuttle bus bay parking for IT employees. They also provided first class amenity facilities and finally created a futuristic and iconic structure.

 

Salarpuria Sattva Knowledge Park is a cutting-edge IT and ITES business park located in Hyderabad spread over 10 acres of land. This IGBC Platinum rated campus is designed to provide end to end solutions, to the companies operating out of it, as well as the associates working in the campus. The project has a built-up area of around 5 million sq. Ft which includes office space, amenity block and parking and services space. While steel can be a volatile commodity, it is one of the most important materials used in the building. It possesses properties that include durability, versatility and strength making. When buying steel, some parameters like identification mark from the manufacturing company, ensuring that steel is rust free and reading the technical specifications described in the product literature, can ensure that the structure stays durable for a long time.
MAHESH KHAITAN
Director, Salarpuria Sattva Group

 

Overcoming Challenges & Steeling Edifice
Initially, this building was planned as RCC structure with PT technology. But when it was changed to steel structure, then came the challenges to deal with MEP services, since floor to floor height is fixed.

Steel provides design freedom, supporting architect expectations to design state-of-art buildings and trends of open ceiling designs for interiors. Steel’s long span ability creates space eliminating intermediate col / load bearing walls.

It is unique in its ability to provide curved structures, segmented structures, twisting beams for ramps and skylight structures etc. It is also earthquake resistant, due to its ductile and flexile properties and has considerable capacity to resist lateral loads caused by wind and cyclones. It is rapid, effective and practical.

The assembling is quick and efficient in all seasons. Due to prefabrication capability, the structure can be assembled off site and erected in days. This offers time saving, when compared to bottom to top activities in other construction methods.

Steel is also lighter in weight which reduces the foundation sizes which minimizes the excavation of natural ground. Considering time saving, mechanical equipment utilization and manpower dependency, it proves to be cost effective with earlier return on investment. However, the initial cost is on the higher side when compared to other construction methods. Steel-built buildings are often more adaptable, with greater potential for alterations to be made over time, extending the lifetime of the structure. Steel structure creates less – dust, noise, site related wastages. With extensive testing methods, experts have gained the knowledge of how it reacts to fire. All the codal requirements with various materials allow for precise specification of fire protection.

Uniqueness
The Iconic façade of Tower 2 is inspired from the Bar Code Pattern of Digital Revolution- A bar code is a method of representing data in a visual, machine read format. It is represented by widths and spacing of parallel lines.

The multi – colour bar code pattern glass has been the highlighter of this signature façade, keeping all LEED / IGBC Platinum Rating in mind. Rolled glass has a distinct pattern on one or both surfaces. It is a decorative and translucent glass, with patterns on one face. In addition to diffusing light and obstructing visibility from the outside, the figures soften the interior lighting.

Amenity Block Façade also is Dynamic in form. The shape of the amenity block façade is a visual treat and will offer an enhanced aesthetic experience. The amenity block façade is more durable, cost effective, energy efficient and environment friendly.

Structural steel plates are procured from Jindal factory and the built-up sections are manufactured at JSSL factory.

 

Fact File

Architect: RSP Design Consultants Pvt Ltd
Structural Consultant: Design Tree Service Consultants Pvt Ltd
Steel Fabricator: JSSL Severfield Structures Limited
Steel Tonnage: 25,000 Tonnes (Approx.)
Status: Ongoing

Prestige Kingfisher Tower, Bangalore

The majestic Kingfisher Tower located in Bangalore has been built by Prestige Construction and United Breweries to serve as a luxury residence. Architects Thomas Associates and Structural Engineers Sterling Engineering Consultancy led proficient design teams to the completion of this urban edifice.

Client Brief
Client brief was simple, when it comes to a complete analysis of structural safety, the magnitude of the task at hand can be assessed. It’s not the first time that the team was asked to design a penthouse for a client, but it was the first penthouse designed that sat atop a thirty-three storey mega-structure with cantilevered landscaped gardens, an infinity pool, and a helipad!

Architectural Features
The residential structure was planned for three towers of twenty-seven floors each, which share common basements, parking levels and entry levels.

Two basements levels and four additional floors above the ground provide parking for the triplet. From the fifth floor is the residential suits which continue till the thirty-third storey. From the south face of the structure, five distinct levels house recreational floors at five storey intervals to house swimming pools, landscaped gardens and gymnasiums.

At these floors, the individual towers connect to create a large base plate. From the north face of the structure, at the thirty-third floor a swimming pool rests on top of the tower and a cantilevered garden projects 18 meters beyond the structure on either side.

The designed scissor shape inclined struts support this structure which stands out as a unique feature in the north elevation of this structure. The complexities in design started as early as the foundation, but the enthusiastic and every-ready design team considered all challenges as opportunities for innovation and learning.

The foundation of the structure was designed as per the soil investigation reports as isolated footings. An unexpected finding after excavation showed the loss in bearing capacity of the soil around the bore holes taken for testing. This led to redesign of the isolated foundation under the west tower. The variation of floor plan from parking to residential suits to intermittent recreational floors and subsequently the penthouse required floating of major columns.

The southern elevation shows five prominent recreational levels which have restricted beam depths and floating columns. The structure designed as a R.C.C framed structure benefited from the use of Composite Construction in specific large load carrying members. The connecting areas are supported using a metal deck slab spanning between a network of structural steel beams and girders to create a large base for the recreational level. The use of structural steel not only helped in avoiding shuttering but also minimized construction time. Composite construction reduces the cost of the structure as compared to construction in solely R.C.C or Steel and significantly reduced structural member sizes and considered aesthetics of indoor spaces.

 

With an eye for aesthetics as well as structural integrity, Sterling Engineering proposed the use of inclined scissor-shaped struts to support the cantilevers at the penthouse. These unique features as compared to simple-inclined struts makes the structure stand out. As seen in the north elevation a single strut establishes itself from the 27th floor column and splices into two members. This junction uses a steel mechanism embedded into the slab to distribute the loads. Precast R.C.C. brackets were fitted with steel plates for bolted connections to the hollow steel sections of the struts. The splices terminate at the base of the cantilever at the 33rd floor and are fixed using a steel plate and bolt mechanism. Two such identical scissor arrangements under each cantilever along with the help of cross bracings provide lateral stability. Provision of a secondary bolt fitted under the primary bolt ensures safety in case of failure or slip until repairs are carried out.
Amit Shantanu Shinde
Project Leader, Sterling Engineering Consultancy Services Limited

 

Geometrics
Space constraints in and around the construction site due to surrounding structures and roadways restricted the location of construction cranes on the south end. Communication between the structural consultant and contractor regarding crane loading, moment calculations and safety is essential to ensure that cranes provided on site are adequate to lift members and deliver equipment.

This structure made use of two cranes placed on the south side of the structure which outstretched their arms to provide support to the northern end of the structure during construction of the scissors and cantilevered girders.

To provide enough stability to the cranes, slabs of two floors under the crane base were supported using props which were removed post-construction. The structure did not require provision of a central core with shear walls as the stiffness of the towers was enough due to its intermittent connections at recreational levels.

The unique aspect and a design challenge of this structure was the two-storey Penthouse. An additional transfer level at 33rd floor was required to support the penthouse at 34th and 35th level. As seen in plan, the penthouse cantilevers in three regions, two on the north end carrying landscaped areas and one at the south supporting the penthouse.

The penthouse is supported on thirty-three-meter-long and five-meter-deep structural steel trusses which are resting on southern peripheral columns. Within the penthouse area we have achieved a column free space spanning fifteen meters which is supported on one-meter-deep rib beams all skilfully placed to consider aesthetics.

With an eye for aesthetics as well as structural integrity, Sterling Engineering proposed the use of inclined scissor-shaped struts to support the cantilevers at the penthouse. These unique features as compared to simple-inclined struts make the structure stand out.

As seen in the north elevation a single strut establishes itself from the 27th floor column and splices into two members. This junction uses a steel mechanism embedded into the slab to distribute the loads. Precast R.C.C. brackets were fitted with steel plates for bolted connections to the hollow steel sections of the struts.

The splices terminate at the base of the cantilever at the 33rd floor and are fixed using a steel plate and bolt mechanism. Two such identical scissor arrangements under each cantilever along with the help of cross bracings provide lateral stability. Provision of a secondary bolt fitted under the primary bolt ensures safety in case of failure or slip until repairs are carried out.

Using Steel
The variation of floor plan from parking to residential suits to intermittent recreational floors and subsequently the penthouse required floating of major columns. The southern elevation shows five prominent recreational levels which have restricted beam depths and floating columns. The structure designed as a R.C.C framed structure benefited from the use of composite construction in specific large load carrying members.

The connecting areas are supported using a metal deck slab spanning between a network of structural steel beams and girders to create a large base for the recreational level. The use of structural steel not only helped in avoiding shuttering but also minimized construction time. Composite construction reduces the cost of the structure as compared to construction in solely R.C.C or steel and significantly reduced structural member sizes and considered aesthetics of indoor spaces.

Sterling Engineering’s design team at the head office in Kurla, Mumbai performed all design related calculations and drawing submittals and all site inspection visits and reporting was carried out from Sterling’s Bangalore office to ensure fast response to our clients. The project was completed in 2018 and has been a landmark project for the city of Bangalore and all disciplines associated with it.

Learnings & Technology
ETABS software was used to model the building’s RCC and Composite members. To design the unique scissor-struts STAAD Pro was used. All outgoing drawings are drafted using AutoCAD.

Sterling Engineering has worked with Prestige Developers of Bangalore in the past and has always pushed for a call for innovation and efficiency in our designs and submissions. They value all their relations with all disciplines that thoroughly enjoy the work.

The city of Bangalore has many upcoming landmark developments which we hope to be part of soon. As all construction projects are concerned, coordination and managed are key to successful and timely completion. The project was competed in four years.

Fact File

Client: The UB Group
Developer : Prestige Estates Projects Ltd
Architect: Thomas Associates
Structural Consultant: Sterling Engineering Consultancy Services Pvt Ltd
MEP Consultant: Design Tree Service Consultants Pvt Ltd & Cerebration Consultants
Steel Fabricator: Eversendai Construction Pvt Ltd
Steel Tonnage: 1850MT
Status: Completed

Bhubaneswar Airport, Odisha

Design Intent
The brief of the proposed terminal building posed a challenge to meet the aspiration of passengers which was to have a glimpse of such a large treasure of culture and heritage. The existing terminal building stands in stark contrast to the old building in terms of planning, design and technology which furthers the challenge for the proposed design to bring in harmony and balance.

Thus, the main brief was to understand the rich cultural heritage of the place with its art and architecture and to identify various aspects in terms of spatial configuration and building elements from local architecture which can be incorporated in the built form, interiors and landscape of the terminal building with context and theme.

Ideation
Talking about Orissa the first thing that strikes one’s mind is the great “CHARIOT PARADE” or the “RATH YATRA’ of Jagannath Puri which gives meaning to every aspect of a journey and hence to life. Through this project, the intend to bring that experiential feel to life for the visitors along with showcasing the ancient and modern elements of Bhubaneswar to give complete meaning to every journey whether from or to this magnificent city.

Steeling Essence
With constant reviewing of technological advancements and updating the material is recommend for design and construction. Steel is a preferred material due to its versatility. Steel’s strength to weight ratio enables light weight forms and flexibility in regenerative design projects. Steel’s malleability and ductility along with cost bends to our will to create ever larger span structures.

Use of steel is also beneficial during time constraints when steel prefabrication can take place off-site and quick assembly can be achieved on-site with guaranteed precision.

Architectural Characteristics
The new airport is envisioned to create a fusion of traditional and modern architecture, adopted from the symbolic Jagannath Rath and Konark wheel, in the spirit of movement. The corbelled roofing profile for the building form as well as the stone bands with motifs is replicated on the front facade, creating a distinct style in aviation architecture. The division of the vertical massing on the bullnose of the roof of the airport is derived from the topmost part of the temple.

The drop off bay is flanked by huge columns which are designed reflecting the traditional motifs and sculptures while the wheels of the chariot are symbolic to ‘Sun Dial’, both inspired from traditional temple architecture. Using the locally available soapstone for the sundial and the timber for the band with motifs on the top not only retains its original character but also makes it cost-effective. The laser cut jaali with bronze golden finish clearly sets a good example for fusing the contemporary materials with traditional design elements.

The project is a compliment to a holistic development based on the local context, not just in terms of elevation but also volume and space. As the visitors enters the building, they should feel as if they have entered the temple itself. “Architecture has the capacity to influence people’s behaviour and their feelings. Only when they will be able to relate with their surroundings, is when they will experience a sense of belonging and ownership towards it.” As visitors enter the departure area on the first floor, they are greeted by large open spaces flanked with landscaped area and flooded by light wells, thus bringing about the notion of moving through a large temple complex. The entire theme of the airport revolves around taking the visitor through the yatra themselves.

 

This is a very special project since this project changes the perception of how terminals are designed in India. Local art and culture are just not in the artwork but also in the extent of terminal’s interior and exterior design. This terminal is also unique since the passenger flow processes have been digitized, thereby increasing efficiency in processes like security check, baggage screening, etc. The time saved in this process shall provide the opportunity to the passenger to relax in the hold room and enjoy the retail and F&B experience.
Gurpreet Shah
Principal Architect, Creative Group

Art in Architecture
Fifteen days before the yatra the three Gods, Balabhadra, Subhadra and Jagannath are taken for bath with 108 pots of cold water from the sacred well of Goddess Sitala and then covered with Ganesh Vesha (Elephant masks). Huge animals are symbols of power and protection, the same being reason behind presence of huge animal sculptures while entering the temples of Bhubaneswar. “The Lion Guard” intends to bring a feeling of safety, purity and grandeur right from the time visitors enter the building. Additions of 108 kalasha are taken from the Rath Yatra where the deities are washed to rejuvenate them.

The area after the staircase intends to show the phase where Goddess Laxmi is taking care of Lord Jagannath after which he takes permission and comes out for the beginning of the Yatra. The Art installation of a Lotus shell transformation tries to depict this fable. Even in the interior of the building, various artworks have been introduced to reimagine mythological episodes associated with the city and its people. The pillars with the Modern Vahanas on the top would symbolize the Angaraga that depicts evolution, development and how things change and looking at something in a new light.

Inspired by Pattachitra motifs and colors, the check in counter backdrop constitutes of curved lines in the form of garlands and floral patterns constructed of lacquered glass and brass. Even the soffit level of the hold areas is depicted with tribal artworks of brass and thread work with backlighting. The feature walls made of calcium silicate panels digitally printed with local art, wheels of the chariot forming an abstract city skyline and recreation of the grand chariot welcoming the passengers into the city, are all ways to make this building meant as a transit corridor into something much more.

Geometrics
Planning of the building was done not only to ease the conventional passenger flow but also to not invoke the feeling of going through a terminal building, rather a place where people would want to be. To induce this further, granite flooring highlighter bands help in way finding – a technique for promoting a user-friendly design by invoking various senses of the person.

The form of the building – the corbelling provides an advantage in providing skylights of FRP jali made of polycarbonate sheets, thus flooding the building with natural light and reduce energy consumption. The use of materials has also been planned to make the project economically sustainable.

High pressure laminates over the structural columns lend it the required stone finish while using pre-cast members for the structure make it easy to assemble and save time. The structure also uses post- tensioning to increase the structural strength and achieve the required large span structure. Acoustically treated ceilings with wooden panels have also been used to improve the performance of the building.

After the conceptualization of the project and basic decisions regarding the planning, architectural software like CAD and modelling software like Sketchup were used for generating drawings and 3- D for the project. The Building Information Modelling (BIM) was used like CAD, Revit software to simulate and understand the airport and airspace between them. Bhubaneswar Airport gave an opportunity to track building areas for program and gauge the IRR for commercial development.

Experience
The experience of the project was almost spiritual with an aim to design the entire project, from the signage to the artwork on the ceiling as a tribute to Odisha’s large treasure of culture and heritage. It was unique to think beyond steel and large span structures by providing a soul in the building using local flavour of Bhubaneswar. The ideation of the digital flow processes and local terminal aesthetics gave this project a perfect balance to create an iconic design.

The project was initiated in December 2018, when the proposal for the design was floated. The design was conceptualised in the following month and finalised in January 2019.

 

Fact File

Architect: Creative Group
Client: SGS India Pvt Ltd, Airports Authority of India
Status: Under Construction

Phoenix Aquila, Hyderabad

“Phoenix Aquila” is a commercial project situated adjoining Continental Hospital, Finance District, in Hyderabad, Telangana State. The conceptualization while planning was done to create an Iconic landmark in Finance District of Hyderabad with not only a unique aesthetical look but also with facility, services and flexibility of space utilization in the premises for the end user.

Specifications
“Phoenix Aquila” is a commercial project comprising of 2 Blocks – Block ‘A’ & Block ‘B’. The total construction area for both the towers is approx. 26.90 Lakhs Sq. ft. The Block ‘A’ structure has 3 basements + Ground Floor + 7 MLCP Floors + 16 Typical Office floors. The building height from basement is 105.83m and the total construction area is approx. 18.10 Lakhs Sq. ft. The Block ‘B’ also has 3 Basements + Ground Floor + 16 Typical office floors. The building height from basement is 82.3 m and the total construction area is approx. 8.80 Lakhs Sq. ft.

The Structural framing system for the building consists the follows:

  • All columns are RCC columns up to mid basement Level.
  • The Tower columns above middle basement level are composite box columns with self-compacting concrete of grade M 60 / M 50 / M 40 filled in.
  • The lift walls & staircase walls are R.C.C
  • Staircase and lift core portion have RCC beams/slabs in M 45 / M 35.
  • Basement 1, Basement 2, Ground level, MLCP levels, floors are made up of structural steel using high grade (450 for Columns and Beams) structural steel beams with self-supported deck slabs.
  • All three basements have single level car parks and utility services.

Mahimtura Consultants Pvt. Ltd (MCPL) was appointed as a principal structural design consultant entrusted upon with structural consultancy for the complete structural designing of ‘Phoenix Aquila’. The scope of work includes structural analysis, concept and final design, preparation of tender documents for structural works, issue of construction drawings and site supervision as & when required.

 

A conventional slab beam system, though slightly economical compared to a building in steel, there would have been beam / drop panel projection visible in different zones, resulting in reduced clear floor height below the beams, thereby reducing the intrinsic value of the office space. A conventional construction system in RCC, would have taken enormous time to come out of huge basement. But there was substantial construction time saving. Further, this enabled installation of finishes and services in the basements simultaneously, as the superstructure was progressing upward, thereby saving enormous time & cost.

Shailesh R. Mahimtura, Managing Director, Mahimtura Consultants Pvt. Ltd.

&

Hiten R. Mahimtura, Director, Mahimtura Consultants Pvt. Ltd.

 

Highlights
The Project comprises of 2 Towers – Block ‘A’ & Block ‘B’. Both the buildings exhibit completely different behavior. Block A contains a central core with a reasonably symmetrical layout. Block B has three cores distributed across the periphery of the building, depicting an asymmetrical layout. The Two Towers are linked with each other at all three basements and ground level. There exists a cantilever on the perimeters of both buildings spanning three and half meters each and to reduce heavy moments in the beam column connection, a truss was designed with a depth of full floor height.

In order to expedite the construction, “Hollow Filled Columns” (HFC’s) were introduced to reduce the total column shuttering required. The use of self-compacting concrete for the columns in order to overcome concrete segregation, since the height of the columns is 4.05 m. An international design methodology was implemented through a vendor to take advantage of the high-grade concrete infill in the columns. Through, this methodology the thickness of the fire-resistant coating was reduced which in turn lowered the total cost of fire protection. Concrete-pour windows at regular intervals was done in the columns to avoid segregation.

The slab has large spans of 11.30 X 11.30 mts and relatively large column-free spaces was attained despite such large spans. This simultaneously, maintained the head room by providing reasonably shallower beams taking advantage of:

  • Composite action
  • Thoughtful placement of the primary & secondary beams.

The software used for designing and detailing were ETABS, SAFE, RAM and AutoCAD
Structural Uniqueness

Composite Deck Slab System
Self-supporting deck slabs are proposed in basements, MLCP and Office Floors to reduce self-weight of the structure and to achieve speedy construction / faster slab cycle.

Provision to pass services through the Steel Beam
Necessary cutout for running electrical conduits & sprinkler piping system were planned within the web of the I section beams. Flexibility in Air Conditioning ducting routing was achieved by reducing the beam depth, using the composite action in design. As a result, AC ducts could pass underneath the beams & still succeed in achieving desired flexibility. Even after doing this, the head room was not compromised. With conventions slab beam construction system clear height in the office would have reduced hampering the aesthetic and low ceiling height.

Earthquake resistance and fire resistance requirements
The structural design is prepared by designing the RCC core walls (lift walls and staircase area) for earthquake resistance. The balance composite columns are designed only for gravity load path therefore their joint connections remain simple. The columns and beams are coated with cement based vermiculate / intumescent paint to achieve fire protections as per codal norms.

Provision of Sports Arena at Terrace Floor
The entire terrace floor was designed as sports arena acting like a feature for the occupants / end users as a facility. The extra live load, impact load & landscape load have been considered in the design of the terrace slab and tried to maintain similar sections I sections as per the typical floor even though the superimposed loads are heavy in order to achieve, the desired / targeted headroom without changing the floor height.

Large Span cantilever Canopies (Span of 7.5m) provided without tension rod
Large span cantilever canopy with span 7.5 m was designed without any column or any back-tie rods. This was achieved by taking the advantage of cantilever truss brackets around the periphery of the structure. The hanger columns were taken from these truss brackets and were utilized to reduce the cantilever canopy span.

 

Fact File

Developer: Phoenix Tech Zone Pvt Ltd
Architect: RSP
Structure Consultant: Mahimtura Consultants Pvt Ltd
Contractor for Main Civil works: Shapoorji Pallonji Construction Ltd.
Contractor for Structural Steel work: JSSL
Steel Tonnage: 10,500MT

World Center-3 Ahmedabad

Ahmedabad is seeing a rising trend for good office real estate assets, due to rapid employment generation and eminent possibility of the first REIT listings. With increasing traffic woes, distance is becoming an avid concern for businesses. When a company chooses to pick up a good office location an hour away, it sees a lot of attrition. So, a decision was made to provide a world-class business center in the city itself.

Thought Process
One of the biggest advantages of World Center is its strategic location i.e. on Sabarmati Riverfront, an upcoming business district in the center of the city. It also holds its proximity to Airport, Metro and business class hotels making it a hot-spot for business houses to station their offices in an International standard business center.

The focus is always on the quality of development and growth by innovation. The next priority is to minimise the impact on the environment, and, reduce the wastage by encouraging eco-friendly initiatives. In fact, World Center is a Green initiative by Savani Group, and it is IGBC Platinum rated first Green Building in Gujarat preserving natural reserves and substantial cost savings.

The imperative effect
The project team’s values are the foundation to their projects. The same has also helped them earn the most accolades till date and they strive to keep improving for best. The other partners ADS Architect, JLL, Setu, Infra, PDA Associate, Manisha Construction, Savani Infracon LLP on board also bring along the same values to accomplish the mission.

 

World Centre 3 is the unique project in the commercial
hub of the city of Ahmedabad – Steel structure, all around facade,
platinum rated Green building, located on Riverfront is the few special features. Being located at ashram road and surrounded by commercial spaces,
space constraint, traffic congestion was the big challenge of construction

Vishal Sheth
Partner, Savani Group

Mentation
The client believes in designing and creating lifestyle products rather than boxed spaces. Winston Churchill has also said, “We shape our buildings; thereafter they shape us.”

For them, the architectural brief for World Center was of utmost importance, as it plays a vital role in documenting the dream project’s outcome and deliverables. It was clearly one of the ambitious projects with every inch of space designed to give a feel of spaciousness. The architects were briefed to inculcate premium executive’s minuscule needs of work life and ensure the ease, comfort and functional abilities in working space.

Overcoming Challenges
Being in business for so many years and having all types of seasons, the team was prepared for challenges in this project, too. The dream project, World Center, had different sets of challenges especially working from the center of the city with almost no working space.

It was decided to put the labor and material resources in nearby residential bungalows to avoid disturbance on the functional roads. Also, due to the crowd in weekdays, the team used to cast raft during weekends. Having said, all the challenges were overcome in the most efficient way ensuring safety and security for all those involved. The journey of how it was built is also important to ensure everyone involved in the making is happy to give in their best to the vision.

Using Steel
Steel is the world’s most trusted construction material with great flexibility and versatility which makes it easier for designers, developers, and architects to turn their visions into reality. Steel structures are strong, sustainable, and of course, it is 100 per cent recyclable.

There are exciting newer trends in the industry that will likely impact the steel market in a positive way owing to technology and connectivity Savani Group always considers emerging trends into account, as they continue to develop quality lifestyle assets and it is a belief that steel’s longevity, versatility and sustainability will only lead to more from our community to use in more projects, not less. The client is glad to be the leaders in bringing in newer trends in Commercial Reality for the Gujarati businessmen community. For World Centre 3, steel was acquired from one of the best and finest steel providers who hold a remarkable place in the market.

Uniqueness
World Center 3 will mark a new horizon in the commercial realty sector of Gujarat. With its presence in the upcoming Central business development zone of Ahmedabad, it will emerge as a landmark in the new downtown of Ahmedabad in the scenic riverfront. To know about the unique features of the World Center, one should, step in and find himself into a whole new professional arena!

World Center is a class apart for all working professionals. The office spaces are well equipped with all modern amenities and sizes starting from 4800 Sq. Ft. and above.

 

FACT FILE

Principal Architect : ADS Architects,Ahmedabad
Structure Consultant : Setu Infra,Ahmedabad
MEP Consultant : PDA Associates
PMC : JLL,USA
Civil Contractore : Manisha Construction
Steel Fabricator : Tender in process
Client : Savani Group

Atmosphere, Kolkata

Atmosphere is conceptualized as an ultra-luxurious residential project with 80 villas and with a vision that each villa should be unique. The structure is an icon for its overall vision, the architecture expression and the engineering determination. Deya enthralls that moment of inspiration, and it make the dream float through the cloud to its destinations, into an amazing atmosphere

Setting up the squad
M N Consultants role was that of a structural engineer. Along, with concept designer web structure they had the responsibility of transforming the owner’s dream into working reality. There were various aspects of design like mep, architectural, infrastructure which had to be worked on with, and, create a structure which is suitable for all their needs and safe in all aspects of design.

Structural Aspects
A B+G+37 stories high rise condominium with ‘Deya’ the connecting bridge at a height of 100m from the Ground level. The magnificent hanging sculpture is intended to look a floating cloud between the peaks of the two towers. The structure will span more than 320 feet in width, 55,000 square feet of usable space having a silver lining façade featuring numerous kinetic discs. It comprises more than 1,500 steel sections with a total weight of 2340 tons, assembled 100 metres above the ground.

The structure had to straddle between two towers in a combination of a “beamlike “and a “catenary” system. The primary challenges facing the structural system includes fundamental issues of safety and serviceability, as well as the critical issue of constructing such a large structure some 40-floors up. Limiting and controlling the movements of the towers at the roof levels, where, the cloud structure is supported, whilst maintaining serviceability of the towers and the sky-bridge under seismic loads and the high wind forces that prevail in Kolkata have been the primary structural considerations.

Challenges
The primary challenges facing the structural system include fundamental issues of safety and serviceability, as well as the critical issue, of constructing such a large structure some 40-floors up. To make 100 meter. bridge move independently without affecting behaviour of the building during the lateral movement was the biggest challenge. The second big challenge was to design a foundation system to cater to such huge lateral load.

 

Deya’ a bengali word used by the famous Nobel Laurette Rabindranath Tagore meaning heavenly cloud, and so is the name of the bridge, which is connecting the two towers in the sky in the form of a cloud. It’s a Great creation by the Architect, and not only an engineering marvel but a piece of art amidst clouds at a height of 110m. The concept of the structure behind this piece of art is also a unique in nature. The state of the art design and the concept of base isolation is truly a piece of engineering excellence. The fabrication and erection of the bridge had to be very precise and done with the help of state of the art technology. As a structural designer, guided by the Master Dr. Hossein Rezai-Jorabi, it’s an unforgettable and probably a lifetime experience for me.
Utpal Santra, Managing Director, M.N. Consultants Pvt. Ltd.

Specifications
The structural system is a steel space truss. The space truss is made-up by several distinctive components/hierarchies, each performing specific tasks:

  • Longitudinal Trusses: span between the two towers, and, form the main spine supporting the cloud structure.
  • Transverse Trusses: span between the longitudinal trusses, and, cantilever from them to form and support the actual cloud floor structure.
  • Floor Diagrid: provides lateral rigidity to the floor structure.
  • Horizontal Arches: control lateral movements of the cloud structure.
  • Crown: form the support for the floors and the roof at the ends of the cloud structure over the two towers.
  • External Diagrid: binds all the other components together to ensure they all work in unison.

 

The name Deya literally means the cloud, a cloud is a cloud, light and heavy at once… Deya has been visualized as a sky club seemingly floating between the two tall towers of Atmosphere. The designer’s challenge was to build something as solid and stable and yet be very light. Deya spans between two towers for a distance of 96 M, 72m being the effective span that measures between the two bearing supports. The longitudinal trusses forming the main span, further with transverse trusses, floor diagrid, horizontal arches, roof arches, crown, and, finally the external dia-grid which binds all these components together to ensure that they all work in unison. There are other five aspects of the project which when put together with the sky bridge make this whole thing rather complex or rather sophisticated structure. Firstly, structure of both the towers of Atmosphere needed a strong base to hold the sky bridge in any kind of weather. Secondly, using of UC steel sections of 356x406x1086, having thickness of 125mm and unit weight of 1086 Kg/m. Thirdly, there was a potential risk in movement of Sky Bridge. Every movement was monitored during lifting work. Additionally, Train gauges were proposed to provide at the tension supports. Fourthly, during lifting, vertical deflection were monitored and checked and manipulated with analytical results. Finally transferring the entire Sky Bridge load to 4nos Eradiquake Isolation Bearings placed two at each tower. Constructing Deya makes one realize the flexibility of the steel. From the lifting of the Sky bridge belly to erection of different layers; and finally completing the external façade elements including the fixing of the kinetic discs on the Deya skin, it has been a continuous challenge. Working and being a part of it has been an absolutely unforgettable, unique and extremely enriching; an enthralling experience
Krishnendu Ghosh, Deputy General Manager, Forum Projects Pvt Ltd

 

Exclusivity

The features of the project are:

  • The architectural design intent of the project.
  • The structural design itself has been absorbed to define the architecture.
  • The bridge connecting two 37 storey tower spanning 100 meters build with 2340 Mt of steel.
  • The bridge is not just a walkway it houses four floors which is unique in itself.
  • The tower has big cantilever terraces which was also a challenge to design and built.
  • The base isolation done using special bearing below the bridges.
  • The concept of bridge sitting on base isolation at the height of 120 meter.
  • Limiting and controlling the movements of the towers at the roof levels where the cloud structure is supported, while maintaining serviceability of the towers and the sky-bridge under seismic loads and the high wind forces that prevail in Kolkata have been our primary structural considerations.
  • The way steel structure has been designed with combination of longitudinal and transverse truss along with binding by floor diagrid which is itself one of its kind.
  • The no of bolts, joints that have been provided in this project is really a big number to handle. Total number of welded joints = 1,090 Total number of splice joints = 1,317 Total number of bolts = 30,000

 

Fact File

  • Client: Forum Projects 
  • Architect: Arc Studio, Singapore & Practice Design Pvt. Ltd.
  • Structural Consultants: Web Structures & M.N. Consultants Pvt. Ltd.
  • Contractor: L&T
  • Steel Fabricator: Eversendai
  • Steel Tonnage: 2340MT

 

 

Guwahati International Airport, Assam

The project encompasses a new Integrated terminal building of Guwahati International Airport, an upgrade to the existing infrastructure. A global tender for the project was floated by Airports Authority of India, and DFI in collaboration with Aecom succesfully bid for the same. AAI envisioned the terminal to be an establishment reflecting the aspirations of the place and mirroring the local context. The desired outcome was envisioned to be a terminal that reinforces the Guwahati appeal, a creation that combined contemporary elements with an international appeal to produce a contextually relevant output.

Ideation
At Design Forum International, designs are aimed at creating memorable and awe-inspiring experiences for the users. The Guwahati International airport is conceptualized in a similar vein: the intent is to trigger moments of discovery and togetherness, enhancing user engagement. DFI also believes that it is important to be contextually reverent. The design, therefore, is infused with the flavours of Assam.

The design solution emerges out of the intent to soothe frayed nerves and tired bodies, and to create an environment that evokes memories, stirs wonder, and rekindles pride and a sense of belonging. Designing an airport presents an intriguing challenge; aviation is one of the most complicated industries in the world and runs on incredibly smooth logistics. One has to contend with enormous functional demands, and almost military-level precision.

The architects did not want to restrain themselves to just fulfilling the requirements; they yearned to imbibe the design with an identity – a lingering, almost-haunting memory of the time spent within. It is from this pull and push of forces that a thought emerged: there was a need to create spaces that would involve and stimulate, and not just deliver and facilitate.

Steeling Structure
Steel was the prime choice due to its numerous advantages over other construction materials. Steel provides a much higher tensile, and, compressive strength as against other materials. In case of huge buildings like airports, where huge spans of uninterrupted spaces are a must, steel is the only viable material of choice in the Indian context.


The Indian aviation industry spearheaded by Airports Authority of India is currently registering a 15-20 per cent Compound Annual Growth Rate. Contributing substantially to the annual growth, Guwahati International Airport registers an annual growth of 36 per cent, which is double of the national growth. The addition of a new international standard terminal will only add to this growth by supporting the overflow and paving way further for user expansion. The new airport serves as the second most important entry and exit point to the north eastern India after Kolkata. On completion, it will be able to exponentially increase its operational load, thereby handling the north east segment all by itself. In the longer run, Guwahati International Airport will be instrumental in connecting the north east with international destinations across the globe, especially Asian nations and the south west sub continental countries.
Anand Sharma, Principal, Design Forum International

Uniqueness
Conceived as the iconic Icarus: The epitome of the human urge to fly. The form of the structure takes inspiration from Icarus – the mythological figure who dared to fly. The majestic centrepiece is symbolic and looms over the departure concourse, its arms outstretched as it reaches out to the skies. The floating form doubles up as the canopy for the drop-off zone.

Origami: An art, an expression. Few things straddle the realms of art, physics, and sculpture, as origami does. The childhood memories of flying paper planes, zooming towards the heavens, are reminiscent of individual craftsmanship. While designing, Origami served as a guide to the architects – a companion and a tool as they delved into the evolution of form. Before they knew it, however, the idea dominated the design completely: it finds expression in the terminal roof, the flooring patterns, the column cladding, the theme walls, and even the signage design.

Craft Village: Immersive and engaging. India is a land of diversity: every nook and corner of the land is packed with mysteries and local delights. The airport recreates this experience for the travellers, extending it beyond books and handicraft emporiums.

This enhances engagement, making travellers a part of life at the airport. Spaces have been allocated for the artisans to sit and produce right at the airport, encouraging interaction with visitors. Engaging the craft, the craftsman, and the visitor, in one experience altogether, the crafts village augments the shopping and retail experience for the traveller.

Indoor forest: Wish you were here. Coming out of the plane, the travel weary eyes look for some solace, a relief from the mass of humanity that engulfed them on the plane. It is here that one views an oasis of rich river-basin rainforest from the corner of the eye, and out comes the yearning to be a part of it.

Lo and behold! Wish granted – The visitor is positioned within a 90-feet high indoor rainforest, which needs to be navigated before being reunited with the luggage. The rainforest doesn’t let one just hurriedly pass through; passages that zig-zag through this space bring forth vistas and wonders at every corner.
Craft Walls: Is it an airport or a gallery? The craft walls have been conceived as a canvas for current and future trends: they display innovative products and artefacts. The Namaskar Atrium is a massive double-heighted space that creates an experience for the inbound visitor, with its walls adorned with the art and craft of Assam. The Baggage Claim hall wall is an exercise in modularity with origami aluminium panels that derive inspiration from the hilly terrain of the North-eastern states.

Tea-gardens: On an airport, where else. The tea-gardens are a mark of reverence to the context and serve as an inspiration for landscape design. They are positioned at the front yard along with a water cascade. The landscape weaves a story of its own and clings to the departing and arriving passengers as they walk through it before boarding their pick-up vehicles. The drive up to the departure level is reminiscent of the first climb up a mountain road, after the tiring and relentless plains. The car zooms up as the plains give way to rolling earth-berm greens.

Materiality: An architect’s best friend. To enrich materiality, glass was selected as the palette of choice for the façade – GFRC wraps around the façade’s tricky and smooth wide expanses, facilitating day-light penetration and visual uniformity.

The use of terracotta tiles references the architecture of fort-like citadels and imparts stability. Terrazzo flooring has been employed in the interiors for its versatility and playfulness, whilst the use of granite ensures steadiness. Aluminium origami panels endow relief and sintered stone is used for wall and column cladding.

Geometrics
Few things straddle the realms of art, physics, and sculpture, as Origami does. The childhood memories of flying paper planes, zooming towards the heavens, are reminiscent of individual craftsmanship. While designing, Origami served as a guide to the architects – a companion and a tool as they delved into the evolution of form. Before they knew it, however, the idea dominated the design completely: it finds expression in the terminal roof, the flooring patterns, the column cladding, the theme walls, and even the signage design.

Designing Tools and Experience gained
BIM (Building Information Modelling) software, namely Autodesk Revit et.al.

At the altar of the land of the mighty Brahmaputra and maa kamakhya devi, the new Integrated terminal building at Guwahati International Airport is an ode to the ancient yet reinvigorated spirit of Assam, the Seven Sisters, and our own Incredible India. The construction of the project started in Jan 2018 and is slated to finish by Jan 2021.

L&T Business Towers

L&T Realty, the real-estate development arm of Larsen & Toubro has a presence in Mumbai, Bengaluru and Hyderabad. Its international presence includes sales and marketing representatives in Singapore, Dubai, UK and the USA.

L&T Realty is committed to creating landmarks of excellence, and aims to enrich people’s lives through sustainable developments. It’s vision is to become the most respected real estate developer of the country by building on its execution leadership and by honouring the dual commitments of quality and delivery timelines. L&T Realty’s portfolio consist of 59 million sq. ft. of residential, commercial, retail and transport-oriented development.

Approximately 25 million sq. ft. is a commercial, retail and transit-oriented development which has a direct link with the use of structural steel.

To make any project successful speed, quality and cost are the three major attributes. When we talk about speed and quality, we believe that there is no match to structural steel as a primary construction material, and as far as cost is concerned, economies of scale (i.e. enhanced usage of structural steel) will certainly help in matching the cost to the conventional RCC construction.

Structural steel also becomes very much important keeping in view the recent changes in public policies. For example, the introduction of MAHARERA (real estate regulation act) ensures that the developers not only deliver on time, but also quality and cost aspect of the product are taken care of with 100 per cent transparency.

In a nutshell speed, quality and cost are three attributes which are going to govern the future of building construction industry in India, and it is safe to trust that the maximization of structural steel consumption will take us closer to the achievement of our business objectives.

L&T Realty realize that before starting conceptual design of any project, the developer should direct the Architectural Consultant, Structural Consultant and Services Consultant to start working closely with the project manager to ensure that the cost, time and quality aspects are maintained during the entire lifecycle of the project.

Let us illustrate with an example. If we look at cost bifurcation of any building project, we realize that approximately 70 to 74 per cent of the total cost is attributed towards core, shell and MEP works. The remaining 26 to 30 per cent of the cost is associated with finishing. We also understand that approximately 85 to 90 per cent of the cost is finalized on design table.

If we co-relate cost, time and quality as variables, it is understood that if we take charge of this 70 to 74 per cent of the cost to achieve desired speed and quality, the same will offer a lot of relief to remaining 25 per cent of finishing work which can be worked out in close co-ordination between project manager and the architectural consultant. This is one reason that Larsen & Toubro have chosen to proceed with development of in-house design teams.

L&T Business Towers
L&T Business Towers are located at the junction of Saki Vihar Road and JVLR (Jogeshvari-Vikhroli Link Road) which is popularly known as gate number 3 of L&T. This project is being constructed for the captive consumption of Larsen & Toubro. These two towers are exclusively designed by Larsen & Toubro and are being constructed by L&T Construction which is the largest construction company in India. These buildings are designed and constructed as per the LEED Gold rating norms.

These buildings consist of:
• 1-basement in RCC with 2-podiums,
• 1-stilt & 16-typical floors in composite structural steel.
• Floor plate area is 30000 sqft.
• Column free space is around 13m.
• Floor to floor height is 4.2 m

Evolution of Design – RCC to Composite Steel
We started designing business towers as conventional RCC buildings. Simultaneously, the soil investigation work was taken up by FUGRO. They investigated 24 boreholes along with the geophysical studies of the plot. As we entered design development, we started understanding the following constraints:

  • The senior management of L&T gave us a challenging task of completion of this 11.25 L sq. ft. BUA building with fitouts within 27 months
  • The FUGRO investigation revealed that Basalt of very high compressive strength was available at very early depth of 2m from the natural ground level
  • In RCC structure it was also realized that reinforcement cutting, bending & placing in vertical elements is going to consume considerable time.
  • L&T’s Powai development is in the close vicinity of the Mumbai airport runway & therefore the building height is restricted
  • Looking at the plot geometry it was clear that the site was a logistics nightmare.

 

 

  

To summarize the change in design from RCC to composite steel
with concrete filled tubes is helping L&T Realty to achieve
speed & synergy in project and will ensure the delivery of this G+16 storey
high rise commercial tower within a record time of 27 months.

Ankur Jadhav, Project Manager, L&T Realty

Overpowering Restraints
The bore logs revealed the presence of high-density basalt rock at very early depth of 2m. We realized that we have to excavate approximately 1.5lakh cum of rock which means approximately 22000 truckload of hard basalt rock.

20-excavators started working on project site and when we realized that the same is not helping the purpose, then controlled blasting was deployed to expedite the excavation process. Further, to protect the soil on one side & the only available route for logistics on other side, we had to carry out shore protection work using 1500 micro-piles which was successfully completed in 90days.

We started excavation activity in January 2018 and the building is to be inaugurated latest by March 2020. Keeping in view the nature of rock, the monsoon & statutory constraints we realized that no matter which technology we use for excavation the same is going to consume at least 7 to 8 months for excavation. This challenge was understood immediately after geotechnical investigation was completed in September 2017 and we started discussing a change from RCC to steel structure; however, it was a little early to conclude and move towards Steel structure.

It was towards early October 2017, when we concluded that we are not going to get any additional time to complete the project and no matter what the buildings must be up & running by March 2020, we seriously started thinking about the steel building option to overcome the time delay in excavation.

L&T design team started working with steel framing along with metal deck slab which resulted in considerable time saving of approximately 3.6months. This resulted in slab cycle time of 7 days. We also opted for triple height concrete filled tube columns (CFT columns) which further helped to reduce the time spent on conventional RCC columns and walls. The prefabricated steel framing also reduced site activities to greater extent. Most importantly when we were carrying out our excavation simultaneously the CFT columns and beams were getting fabricated in shop.

Concrete-filled Tubes – Engineering Marvel in Composite Steel Design
As mentioned earlier, RC design was leading us to a time-consuming reinforcement cutting, bending and placing in columns and RC beams. We introduced RC beams in the system keeping in view the lateral drift requirements stipulated in NBC2016.The large depths of RC beams for 13m span were further adding difficulties in achieving floor to false ceiling height.

In order to resolve these issues, we opted for concrete filled tube (CFT) columns with internal steel ribs which completely eliminated the need of reinforcement in columns. These columns were designed in such a way that these columns can be erected for a height of three floors. The core wall of building was checked for slenderness and we allowed the core jump form for three floors as well. This enabled our construction team to proceed with three slab leading to expedited construction activities.

As compared to large depth RC beams we shifted to relatively low depth steel beams. With the issuance of NBC2016 it has become difficult to design the flat slabs in RCC buildings. The steel deck slab not only provided us with a solution in this regard but also, we could eliminate the use of horizontal formwork in these buildings. Similarly, the use of CFT columns eliminated the use of formwork for columns. The jump form offered us relief on slab cycle time as well. The simple beam to column connections also enabled us to expedite construction activities.

Flexibility for Services Routing
13m span was suggesting large depth RC beams which also created a problem for routing of services in these buildings. The introduction of steel beams not only reduced the beam depth but also provided us with an opportunity to introduce castellations in steel beams which offered a lot of flexibility for services routing.

Overcoming the Logistics Challenges
The plot geometry was a logistics nightmare, having a long tail and most of the plot where the buildings are located provided hardly any space for material storage, enabling works and other site related activities.

The steel structure is being fabricated in shop and transported to site using “Just-in-time” principle which eliminates additional space requirement for storing steel members. Use of composite steel structure also reduces the requirement of reinforcement which results in less space requirement for storing reinforcements.

Steel structure also eliminated the requirement of formwork for beams/columns/roller deck slabs, thus eliminating any need for space provision for formwork as well as labour for formwork.

The time consumed in activities like cutting, bending and placing reinforcement, concrete curing, fixing and removing formwork was brought down to such an extent that this not only provided a saving in time but also allowed us to plan site logistics in a disciplined and organised manner.

Initiatives to Achieve Speed & Synergy
Following are the major initiatives which helped us achieve desired project duration to meet our business objectives:

  • Structural steel fabrication in shop during excavation and foundation casting activity at project site ensured that we recover the time lost in excavation.
  • Use of CFT columns with no reinforcement and 3 floor erections in one go opened the construction of 3 floors simultaneously resulting in considerable saving in slab cycle time.
  • Simple connection designs and details ensured the optimization of construction time.
  • Pre-fabricated steel beam with coordinated services cut-outs provided saving in time for MEP work.
  • With the use of Intumescent paint over steel column we could get rid of column cladding work which also reduced the finishing timelines to certain extent.
  • Optimization of site related activities which are related to reinforcement cutting, bending, placing, formwork, mobilization etc. offered us great deal of time saving.
  • In addition to this the skilled manpower requirement reduced drastically due to mechanised construction.

The true success of this project is in the state-of-the-art composite design facilitating large column free spaces along with the optimized floor to floor height, speed of construction & superior quality of final product as formwork is eliminated. The quality of work during the construction and the safety standards followed are typically in line with what L&T is known for.

(Contributed by Sunil Godbole, Senior DGM – Structural Engineering, L&T Realty)

Coleroon River Bridge, Tamil Nadu

The location of existing bridge is in the northern gateway of Trichy city. The bridge connects Samayapuram toll gate with Thrivanalikovil and Srirangam towns. The intensity of traffic through the existing narrow bridge is inadequate for present day traffic.

The heavy vehicles from Trichy to Samayapuram, Turaiyr,Musiri, Namakka, Alem, Lalgudia and Ariyalur are diverted from Trivanaikovil to NH-45 four lane bypass pads, as the existing bridge is narrow and weak.During peak hours, passengers find it difficult to cross the bridge due to heavy traffic congestion. This existing bridge serves as the means of transporting agricultural products to Trichy city from northern districts. Hence,reconstruction of the bridge is very essential for road users for free flow of traffic.

Specifics
The bridge is across River Coleroon at Srirangam TamilNadu. The total length of bridge is 792.0m. It is 4-lane bridge with footpath on either side, with total width of 21.45m. The span arrangement is 24 spans of 33m.The superstructure is with Bow String Arch, with partially prestressing (for tie member) substructureportal frame, with twin piers over pile foundation with 1200mm dia bored cast-in-situ piles.

Geographics
Trichy is the fourth largest municipal corporation in Tamil Nadu,and, the fourth largest urban agglomeration in the state. The city covers an area of 146 Sq. Kmwith a population of 7,52,066 in 2001.It is rated to be one of the fastest growing cities in TamilNadu. During, the last couple of decades, the life style of people, and their commuting habits have undergone radical changes, due to steep hike in the cost of urban land in Trichy, and, the revolutionary changes in major engineering equipment manufacturing, high-pressure boiler manufacturing steel plant and chemical industries.

During peak hours, passengers find it difficult to cross the bridge due to heavy traffic congestion. Moreover, Sriranga Temple – Pilgrims and tourists come to this, and, it is considered as the most important place in Trichy District. Sincethese towns are located on the banks of river Kaveri all the developments, settlements have been concentrated between this river and around.

 

The project bridge is across river Coleroon at Srirangam Tamilnadu. The bridge location is very close to ancient SriRangam temple, and, in view of its attention was paid to aesthetics of the bridge structure, Bow string Arch was selected accordingly. Most of the bowstring arch bridges in our country is with 2-lane & footpath. This is one of the widest Bridge with Bow String Arch.The analysis of portal frame for substructure, carried out with Staad Pro software for various loads and combinations, including wind & Seismic as per IRC Codes.The piles were analysed for vertical forces and horizontal forces with Soil Structure interaction, considering scour levels, with Staad Pro analysis.
B V NAGESH, Principal Consultant, Nagesh Consultants

 

The proposed bridge is connected to important places like Rock fort, Srirangam, Renganather Temple, Thriruvanaikovil, Akilandeswari etc.

Approach Methodology
Stage – I  : Field Investigation:
• Conducting Topographic Survey
• Soil Investigation as per NIT.
• Conducting Traffic Survey as per NIT
• Identifying the Utilities.

Stage – II : Detailed Analysis and Designs
• Preparation of GAD and discussing with the authorities for approval of the same.
• Detailed Analysis of Super Structure and Sub Structures.
• Design of Super Structure, Substructure and Foundations as per IRC Codes and specifications.
• Preparation of Detailed Drawings.
• Preparation of Detailed BOQ and cost estimates.
• Preparation of Tender documents.

Structural System of Bridge
24 No of 33m c/c spans are proposed to suit the Existing Pier location and Length of the Bridge. The overall length of the Bridge from Abutment to Abutment works out to 792m.

Super Structure
Super structure is proposed with Bow string arch girder. C/C distance between expansion joint is 33m, and effective span is 30.75m. Tie members are with cast in situ post-tension girder, other elements are cast in situ RCC member.

Entire super structure shall be cast and cured before the post tensioning operation. Staging provided for tie member shall be removed only after stressing operation.The deck system is analysed using STAAD-PRO software with 2 models i.e., for deck slab as continuous beam of width3-D analysis for remaining elements of super structure.

The Pot cum PTFF bearings are proposed as per IRC: 83 part III. The Jack locations are proposed at 0.75m from C/L of bearing below the end cross girder, and, the load combinations are as per IRC: 6-2010, and, design is carried out as per the guidelines of IRC: 112-201, and, references are made to Euro code, IS codes.

Deck Slab
The slab is supported on cross beams, which are 3.075m apart. 11 cross beams are proposed including 2 at the bearing locations which will rest on the tie beams spaced at 17.25m. Hence, the slab panel size is 3.075 x 17.25, essentially one-way slab. The slab is idealized as one-way continuous slab of 1m width and analysed using Staad Pro adopting effective width of dispersion method.
Codes & Standards
The design of various components of the bridge, in general are based on provisions of IRC/IS codes

IRC: 5 – 1998: Standard Specifications and Code of Practice for Road Bridges, Section I – General Features of Design.

IRC: 6 – 2000: Standard Specifications and Code of Practice for Road Bridges, Section II – Loads and stresses.

IRC: 112 – 2000: Standard Specifications and Code of Practice for ConcreteRoad Bridges.

LOADING:
Dead Load (DL)
The unit weight for Dead Loads calculation has been considered by adopting unit weights as per IRC: 6 – 2000(Standard Specifications and Code of Practice for Road Bridges, Section II – Loads and Stresses).
1) RCC -25 KN/m3

Super Imposed Dead Load (SIDL)
1. Wearing coat -2 KN/m2
2. Crash barrier -7.75 KN/m
3. PCC in footpath/median filling–22kN/m3.

Footpath Live Load
As per Cl: 206.3, IRC: 6-2010 – 5 kN/m2
Vehicular Live Load (LL)

As per IRC: 6, deck slab is analysed for the following vehicles and whichever produces the severe effect has been considered in the design. Following combinations are used:
1) Three class A vehicle.
2) One 70R tracked + one classes A vehicle.
3) One 70R bogie + one class a vehicle.

Transverse Analysis of Deck Slab
The deck slab is idealized as one-way slab of 1m width supported over cross girders supports are assigned at cross girder location panel size works out to 3.075 x 17.25.

Dead load analysis:
Dead load analysis is carried out for 3 cases:
At footpath location.
At Median location.
At Carriage way.

(A) At Footpath Location:
a) Self weight of slab = 0.275 x 25 = 6.875kN/m2.
b) Super imposed dead load:
i) Due to hand rail – 7kN/m
ii) Due to PCC filling in footpath = 0.25 x 22 = 6.16kN/m2.
iii) Footpath live load = 5kN/m2.

(B) At Median Location:
a) Due to Self weight = 0.275 x 25 = 6.875kN/m.
b) Due to median filling =0.30 x 22 = 6.60kN/m
= 13.475kN/m

(C) At Carriage way:
i) Due to Selfweight = 0.275 x 25 = 6.875kN/m2
Due to Wearing Coat = 2.00kN/m2.
= 8.875kN/m2

Analysis for Vehicular Live Load

Vehicular live load analysis is carried out using staad pro with moving load option for following vehicles.
1. Class A vehicle.
2. Class 70R wheeled.
3. Class 70R Tracked vehicle.

Post processing is carried out for 3 supports and 3 spans for above vehicles and reinforcement detailing is carried out for critical values.

Effective width of dispersion

For interior span beff= α x a (1-a/l) +b1———Formula 2

b1= 0.25+2×0.075 =0.40 ( Width of dispersion parallel to support upto the top of slab.
α =2.6, As per clause 305.16.2 IRC: 21-2000, for continuous span with l/b>2.
a= C.G of the load from nearest support.
Calculation of ‘a’

Vehicle moved on the deck with an increment of 0.25m. Load position with respect to critical value of bending moment both for support and span is fond and C.G of the loads corresponding to this location is found .and then C.G of the wheel loads distance from nearest support is taken as ‘a’ specimen calculation for all the 3 types of vehicles are explained in the following.

Impact Factors and Partial Safety Factors:
Impact factor is considered as per cl.208, IRC:6-2010.Following load factors are considered for structural design, IRC:6-2010
i) Dead Load and SIDL except W.C = 1.35
ii) Wearing coat =1.75
iii) Footpath live load = 1.50

Internal Cross Girder
Concrete Grades and Reinforcements:

Concrete: –
For RC Deck Slab (M – 40)

Reinforcement: –
HYSD bars (Grade Fe – 415) conforming to IS: 1786 are provided as reinforcement.

Clear Covers: –
The minimum clear cover of 40 mm to reinforcement has been considered indesign as the site is under “moderate” exposure condition.

Bearings
POT cum PTFE Bearings are proposed as the order of loading is high. 4 bearings are proposed per each span with articulation of Fixed, Guided and Free Bearings.

Sub Structure
Turning pier substructure system was proposed. The twin pier system was analysed for following loads and load combinations –

1) Dead load from superstructure.
2) Live load from superstructure.

Following vehicular loads were considered
i) 2 class -A
ii) 4 Class A
iii) 70R vehicular + 2 Class A
iv) 2 – 70R vehicles

Vehicles on one span & both span was considered.

3) Longitudinal forces as per IRC:78.
4) Wind load.
5) Seismic forces.
6) Water current forces.

Load Combination

  • Load comb 99 dl+ll on one span with if+bf+ff.
  • Load comb 100 dl+ll on both span with if+bf+ff
  • Load comb 101 dl+ll on one span without if+bf+ff.
  • Load comb 103 dl+ll with if+bf+ff+wind on ss+(wind on ss+ll)+wind on pierbeam.
  • Load comb 104 dl+ll without if+bf+watercurrent+ff+wind on ss+(wind on ss+ll)+wind on pierbeam + wind on pier stem
  • Load comb 105 dl+seismic trans(dl)+0.2vll+0.5bf+ff+sf+water current.
  • Load comb 106 dl+seismic(longi) dl +watercurrent

Foundation
Pile Foundation with 4 Nos of 1200mm dia RCC Bored cast in situ Piles under each columns are proposed with Pile Cap at Top. The Founding Levels/Pile termination levels are fixed based on the required Pile capacity. In general Piles are terminated by socketing depth of 5dia of pile into disintegrated Rock or 0.5 dia into hard Rock.

Cement concrete pavement with 75 mm of uniform Thickness is proposed in M30 grade of Concrete. Deck is proposed with 2.5% camber in transverse direction to drain off the water with drainage spouts proposed at the edge of Kerb. Footpath with Hand rails is proposed on both side of bridge to facilitate pedestrian movements.

Encounters
The challenges faced are as follows:

  1. Analysis of Bow String Arch for 4-lane & footpath on either side, with 2 nos of Bow-Strings.
  2. The critical design of the foundation, as the bridge is proposed very close to old existing single lane steel girder bridge with pile foundation.

 

Fact File

Client: Tamil Nadu Highways-Trichy
Structural Consultant: Nagesh Consultants
Contractor: P.K.Mookanambalam & Co
Steel Tonnage:
a) Reinforcement Steel – 3200 MT
b) High Tensile Steel – 150 MT

Hager Electro (India) Pvt. Ltd, Pune

The client being German company by origin, was very clear about their requirements. In addition, to the production requirements they wanted to setup a revolutionary plant that would adhere to their philosophy of continual progress and superior quality. The brief mentioned the need for a green, maintenance free, sustainable building that adapted to the changing climatic conditions. Being Europeans, their work environment needed to have a mix of blue grey and white as they believe these are the colors of effective work environment.

Initial Thought
The initial thought to achieve the above brief steered the architects towards finding sustainable and energy efficient systems, which, can be automated to provide work environment that is AI (Artificial intelligence) controlled yet has a low carbon footprint. The need to create space, that was both aesthetically pleasing, and, maintenance free led us towards steel buildings technology and insulated panel walls.

Steel the necessity
There are three things that are integral towards making a project successful:

  • Cost of the material is significant in setting up any new project. Steel buildings are cost effective as they can create longer spans creating larger production spaces, they have good scrap value, they can be disassembled and reassembled easily, they are recyclable, and they are easy to transport.
  • Quality of production of steel is controlled by various norms and the fabrication (PEB- Pre-engineered buildings) are designed with various highly sophisticated software’s and are designed as per AISC and IS 800:2007. The whole production is mechanized thus giving us much more quality than a manually fabricated structure.
  • Time:The production of buildings is much faster as the whole process is mechanized. The erecting is also very fast as compared to RCC structures. Transportation is faster as the members are much lighter as compared to pre- cast RCC.Thus, steel was chosen to make the project cost effective, time bound,quality, conscious and sustainable.

Aesthetics
The building is provided with puff sandwich panels which make it look aesthetically appealing. These panels have been used for external cladding as a cavity wall. Glass facade has been used in elevation to capture more sunlight and to decrease the use of artificial light in building.The materials like ACP, Glass, are being used to create a Facade and fenestration that are not only aesthetic, but also contributes to saving energy.

 

The project was more so challenging as we had to convert a design which was frozen on a green field onto a campus of existing buildings, this meant removal of certain columns, strengthening of remaining columns, increase in height, modifying the roof structure to hang a walkable false ceiling. Improved aesthetic values internally and externally, choice of modern materials and latest technology towards walls, flooring, windows, ceiling, etc.and add a flavor of streamlined layout with a provision of green covers around the building to highlight the same. The Hager was a challenging project to achieve perfection in design performance, European standards as against existing brown field features. I am sure those who have seen the old structures and campus will have a shock and surprise when they see the newly designed and erected structure on the same piece of land without bringing down the old structure
Prashant Deshmukh
Principal Architect, Prashant Deshmukh & Associates

Sustainable Design Concept
Puff sandwich panels have been used for external cladding as a cavity wall which will reduce the temperature by 5 degree Celsius. It has a high load bearing capacity at a low weight. Puff sandwich panels are also used for false ceiling and was designed with the griple system. The false ceilings are walkable and enables good enough space to run services and utilities.

An evaporative cooling system has been used instead of HVAC. This system relies on adiabatic cooling. It saves electricity and operational cost is reduced, using the evaporative cooling system. Evaporative cooling system allows fresh air to circulate throughout a building and it forces hot air to displace out. Evaporation is a natural process and it does not require any refrigerant. It eliminates odour and state air out instead of recirculation.

Turbo vents provide year-round ventilation. These are low cost and high-efficiency vents which make them an extremely popular ventilation component. Roof vents and turbines must always be used with adequate soffit venting to meet minimum ventilation code requirements. It is needed to replace the turbine vent when it stops spinning because properly functioning turbine vents spin with the slightest wind.

Building management system has been used to control lighting/air conditioning/fire protection. Physical movement sensors are installed to save the energy. The use of right colors helps in reducing the heat penetration and help to be more sustainable. The false ceiling was designed to be walkable to cater the maintenance of all the utilities above the false ceilings.

Design Geometrics & Software used
The Germans strongly believed in squares and rectangles, not only for plans but also for elevation. The sandwich panels fascia is therefore, made to run across the periphery, hiding the roof profiles while achieving uniformity. The elevations are proportionately designed to suit the scale. The rectangular geometry is achieved through various façade elements including glass, ACP, and sandwich panels or powder coated aluminum louvers. The metallic grey framed design highlights the profile of the building with the strong language of squares and rectangles. A large curtain wall in the corner of the office building highlights the entrance automatically due to the scale and tint of the glass.

Software like AutoCAD was used for designing purpose, and software such as Stadprov8i, E-tabs were used for the structural detailing part of +the design of steel and RCC structures, MBS and Tekla for designing PEB structures; other than thatGoogle sketch up, 3-D Max, Lumion used for 3-D modeling and Photoshop and Microsoft Power Point used for presentations.

Experiences
Working with MNCs is always tough, as they are very aware of the requirements, quality standards and technological advancements. However, the architects loved the challenge of adapting new technologies to fulfill all the clients requirements by setting the bar for quality standards very high. The learning curve for the whole team was astounding. By the end of the project the whole team had becomehabitual to using and maintaining progressive techniques of communication, effective reporting, error free drawing delivery and predictive project monitoring.

The design took around a year for its completion. It commenced in Feb 2015, there were four revisions made in the design, The design got finalized in June 2015. The commencement of the work was in August 2015. The earlier completion date for civil works was given as May 2016, the total work was completed and handed over to the client in Oct 2016.

SUSTAINABLE OFFICE COMPLEX
STEEL DAY 2020
SSMB AWARDS 2020

SEND YOUR STRUCTURAL STEEL PROJECTS

Facebook