Page 72 - UL_Report On_Part 1
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63 IITGN-UL/Façade                                                                                                                                                           64 IITGN-UL/Façade































                                                                                                                                                                                                                  20’’ c/c spacing

                                                                                                                                                                                                                                                                      Image 21: Distorted deck slab due to direct exposure of fire on failure of cement boards

                                                                                                                                                                                                   Image 20: Failure of cement boards and POP sheets due to
                                                                                                                                                                                                   improper workmanship






                                                                                   (d) Role of POP and cement boards in providing fire protection to deck slab


                                                                                   POP sheets of thickness 12 mm and size 3’ x 3’ were provided protecting the deck slab
                                                                                   with joints filled with POP paste. Double layer protection  to beams and slab was
                                                                                          provided through cement boards fixed to MS square pipe sections as in Test 1.
                                                                                   Cement boards of 12 mm thickness and size 8’ x 4’ were fixed to beam base level with
                                                                                   SDS type screws fixed at 20” c/c unlike test 1 at a distance of 8”. The reduced thickness
                                                                                   of cement board and increased c/c distance during fixation of cement board led to
                                                                                   premature failure of boards under fire. Failure of cement boards caused fire exposure
                                                                                   of POP which failed subsequently. Continuous exposure  to direct heat led  to
                                                                                   distortion of deck slab of ground level compartment at certain locations.  Thus,                                                                               Image 22: Failed POP sheets on exposure to fire
                                                                                                           workmanship during structural fire protection is important.
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