Club house/cafeteria-Tensile Structure fabricator at BKC Mumbai
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Existing 2 level cafeteria -club house-Gym having open terrace type structure on level 2 , used for open air seat out. The requirement is to cover the open air seat-out with a fabric to protect against excessive sun & Rains. Also to arrest water leaks to the levels below. (Presently a lot of leakages are observed which were literally un-pluggable).
The challenge was to transfer all the loads to existing columns - Beams without disturbing existing interiors- exteriors. The client did not have structural drawings of the existing structure showing column beam positions. Most of the wall/ flooring were gladded with stone, wood, fiberglass, glass etc. At places the gap between the civil structure & wall was more than 750mm. Only way one can find out internal structure was to physically examine false ceiling or drilling few holes at place to judge internal details. All the time Restaurant has to be functional with easy movement of people and materials.
The total plan area of the Club House/ Cafeteria in BKC Mumbai is 300 sq. Mtr or 3000 sq. ft.
From Legal point of view Fabric - Tensile Canopy structure was the only option feasible. Due to limitations in data available for the existing architectural structure size & location, naturally initial presentations were made with considerable steel members supporting the multi-point Hyper. The roof form was accepted however in the middle of the project the architectural roofing was decided to be extended further then outer periphery of the Terrace by at least a meter, complicating the structural issue further.
After considerable thought, our Tensile Structure fabricators team decided to have a structural design form free of any bending moments, where in we would be transferring all the reaction forces directly to the major columns we located from the levels below. Our Tensile Structure Manufacturer team anchored members directly on columns through pin joints. We used fairly long members to ensure the coverage as desired.
At locations where the columns were not in the vicinity, we creatively took supports from 2 adjacent beams with slanted members meeting at the desired anchor points again having Pin joints in the base.
This eliminated on site work time to just a week, where all the members were now fabricated to final form in our Factory. Only the base plates with flanges for pin joints were inserted at the column positions & recalled again. The normal functioning of the Cafeteria continued right until the fabric was installed.
Detailed Analysis of the structure was carried out with FORTEN3000 FEM- Membrane analysis software. In absence of Local codes for Governing construction of PTFE Tensile fabric structures, British standards were followed to generate wind loads depending on geometry, height of structure, height from sea level, distance from sea, surface roughness, topology, etc .
Once structure was analyzed, the dimensional detailing of each individual structural members were carried out after STAAD analysis depending on the max. Load generated in load combinations. Auto cad 2011 was used for drafting purposes.
Almost all the members were fabricated form Hollow round tubular ERW pipes of Diameter, 138mm X 6 mm. The base plates of 25 mm. thickness with 20-25 mm. flanges for pin joints were machined - fabricated.
12 mm galvanized wire strands were used to reinforce fabric, as well as to support struts in angular positions.
The Fabric used was Type 2 Mehler Mehatop 900. The weld joint of 38 mm Lap was used.
The single piece fabric was lifted to the upper level. The fabric was fixed in aluminum kedar profile which in turn, was clamped on the steel structure through self threading screws.
The rest of the fabric was anchored through assembly of SS316 end plates, turn buckles, M20 Studs, Ball washers, Nuts etc. The whole installation was complete in 3 Days.
