Located in suburb of Hyderabad in southern India is one of Amazon’s largest campus outside of the US. The building consists of two tower, the nort and south tower, which are connected at all levels with three bay over laps. The project consists of 21 levels of post tensioned bonded system for various parking floors, office floors and helipad floor.
Scope of Post Tension:
The Post tension scope of the project for all 17 levels totals upto overall area of 2,580,000 sq.ft (approx 240000 sqm) which was completed in a period of 20 months. The slab panel sizes in typical floors is around 15mx12m.
Structural use of PT:
By the use of postensioned flat slab systems in structural design this enabled incoporating large floor plates with minimal column obstructions and more floor to floor clear height. Using post tensioned floor system allowed for thinner slabs with drop panels which helped in reducing the overall concrete quantity, steel reinforcement quantity and mass of the building which lead to direct cost savings.
With the reduced mass advantage from Post Tension systems the sizes and reinforcement of columns and foundations of the building could be reduced which leads to indirect savings.
Apart from the regular office and parking structure, Post Tension was used in the design of Podium slabs where loading greater of 25kN/sqm was faced on account of movement of fire trucks as well as landsacpe. With PT systems we were able to limit the sizes of the slabs over 15m spans to allow maximum floor height of below parking slabs. Also the for helipad slab we used post tensioned beams and slabs where we considered dynamic loading in design.
Design Tools for Post Tensioning:
A valuable project requires reliable design software with which design revisions and alterations could be made easy with time. The three primary design tools applied in the Post tension design are RAPT, ADAPT and ETABS. The Post Tensioning floor needed to be cross verified with each of the design tools so that the results satisfies all the criteria with different methods of analysis.
Commercial and construction advantages:
- With ability of post tensoning to balance loads and reduce deflections thus helps in reducing the slab thickness.
- Reduced slab thickness compared to conventional slabs provided direct savings in concrete consumption and beenfits the column and foundations design.
- By using PT we are having savings in steel reinforcement consumption not only in the slab but also for vertical members.
- By proceeding with flat slab PT system we are saving costs in formwork.
- Earlier removal of formwork can be facilitated as within 3-5 days stressing of tendons can be done.
- PT also helped in overall faster consutruction time and ensuring project was delivered on time.
- For Helipad slab by the use of PT system we were able to reduce reinft consumption and concrete consumption with reduced slab sizes.
- Overall by proceeding with post tensioning we are having cost saving in consumption of materials as well as resources.
Thanks to post tension desgin solution the client,architect and contractor are able to meet their expectations within their contruction budget and time.
- Ower: Amazon
- Location: Hyderabad,India
- Architect: CRN
- Structural Consultant: Ramboll
- Contractor: SPCL
- PT specialist: Utracon India
For Further Details
Utracon Structural Systems Pvt Ltd
No. 45, 5th street, Padmanaba Nagar, Adyar, Chennai – 600020.
Ph: 044-24468001/ 02/03