Page 24 - UL_Report On_Part 1
P. 24

17 IITGN-UL/Façade                                                                                                                                                           18 IITGN-UL/Façade




         4. Construction                                                                                                                                                              b. Deck slab
                                                                                                                                                                                      Deck slab at all floor levels is provided with 1mm thick trapezoidal steel decking       Image 4 shows  the placement of
         a. Steel frame                                                                                                                                                               sheet and composite action is achieved by fasteners in form of SDS screws of size        thereinforcement  wires  on  the  deck
         Structural frame consists of Indian standard steel sections for beams and                                                                                                    18×25 mm at a spacing of 300 mm center to center through deck sheet onto the             sheet for achieving composite action.
         columns. ISMB 600 members used for columns whereas ISMB 400 members are                                                                                                      beams. The slab was cast using M-25 (1:1:2) design mix concrete (Figure 9) with OPC
         used as beam sections. Beam column joints are connected with connector plates                                                                                                to provide a maximum floor thickness of 127 mm. This incorporates an anti-cracking

         through flexible end plate connections. These connections consist of a single                                                                                                mesh consisting of 8 mm Fe 500 diameter wires at 230 mm center to center.
         plate fillet welded to the end of the beam and site bolted to either a supporting
         column or beam. Image 2 shows the steel structural frame comprising of beams
         and columns. Inset of Image 2 shows flexible end plate connection with three

         bolts fixed to the web of beam sections.












                                                                                                                                                                                                                                                                              Image 4: Placement of reinforcement wires
                                                                                                                                                                                                                                                                              on the deck sheet


                                                                                                                                                                                      Figure 9: Cross sectional view of deck slab








         Image 2: Steel structural frame comprising test facility                          Image 3: Column base plate fixed with
                                                                                           pedestal using HSFG M-30 foundation bolts

         For analysis, these connections were considered as simple supports due to the
         absence of continuity of beams across the connections. 8 steel columns are fixed
         to concrete pedestals at base level through High Strength Friction Grip (HSFG)
         M-30  foundation  bolts  with  20mm  thick  column  base  plate.  Each  ISMB  600

         column section is fixed through base plate with 10 foundation bolts.
   19   20   21   22   23   24   25   26   27   28   29