Noida World One is a commercial project with corporate offices/IT and retail showrooms. The project consists of five towers having 30 storeys with parking at the basements floors, retail showroom at next two levels and then office floors. The top floor is a terrace garden and swimming pool. The three towers are inter-connected with 30 m long bridge giving a look of a big floor plate at the top. The towers have been conceptualized with composite columns and steel beams and bracings.
As the structure is located in high seismic zone and owing to its sleek geometry and height, the structure is more vulnerable to wind and earthquake forces. Therefore, to cater to the lateral load, an optimum combination of shear walls and bracings were worked out to achieve economy and construction speed. The framing of the building has been designed to provide large office spaces without compromising on the clear floor-to-floor height.
It has been a pleasure being associated with the Noida World One project. We have tried to implement avant-garde design processes for this structure in order to increase the efficiency of the building and making the design sustainable by saving the quantum of material. The Indian codal provisions have yet to develop further for composite structures. However, the use of Eurocodes and American design codes and further research helped out in the design. I am happy to thank the project head -Prabhat Bansal for his contribution and active leadership in the project. Contribution from Abhishek Jain have also been substantial to the project.
DR. VINOD JAIN, MD, Vintech Consultants
Due to the rectangular sleek plan of the building, the deflections are high along the shorter dimension. The requirement of open spaces without obstructions and controlling the lateral deflection to maximize the comfort of the inhabitants, the shear walls have also been provided. The foundation system is a raft. The plastic analysis of the structural members is considered in design of the structural steel members. The effect of concrete in providing additional strength and stiffness i.e. composite action is considered both for beams and composite columns.
Structural steel is used in conjunction with concrete efficiently utilizing both materials. The reduction in self-weight of the building and reduction in construction time are added benefits of using the composite frame buildings in comparison to traditional RCC structure. I sections are used for beams and columns. The columns are built with E 550 grade steel and beams are made up of E 450 grade steel. Availability of high strength steel at a modest outlay and considerable reduction in total weight were an appreciated advantage of the steel-concrete structure.
Generally fabricated built-up steel sections are used in this building. Columns at lower floors are I-sections of 700 mm depth and 400 mm width encased in M70 grade concrete having outer dimensions as 1000 x 1200. The bracings are square hollow sections. The beams are I sections, with primary beams on typical floor have 600 mm depth and secondary beams ranging from depth of 350 mm to 600 mm. The periphery beams are chosen as the channel section for a superior look to the façade. Special attention is paid to reduce the different type of beam, hence achieving economy and speed by limiting type of joints and optimizing beam fabrication process.
Challenges & Complexities
At the two basement floors, the requirement of clear floor to floor height is more, therefore, the depth of the beams have to be limited to 425 mm. The location of the bracing countering the deflections in the shorter direction is limited due to the requirement of open spaces. Therefore, many iterations were done in order to have a perfectly working structural system with shear walls and bracings. The bridge connecting the towers had to be designed and modeled with appropriate structural assumptions.
The trend of using structural steel in commercial and residential buildings is slowly catching up in India and World One is one of it. The 30-storey tower houses commercial and retail spaces and the towers are planned to be finished in 45 per cent of the time of a traditional RCC structure. The project is located at a lucrative address on Noida Expressway providing great accessibility, spacious homes, well-lit, modern and equipped with the latest amenities. Enhancing their accessibility is the fact that these offices are located next to the proposed metro station with FNG connectivity. The bandwidth of Noida World One gives consumer the option to choose from a wide range of offices suited their needs.Although the steel manufacturer is yet to be decided,the sections used for column and bracings are fabricated sections. However, beams are mix of rolled and fabricated sections.