KOCHI: Observing the recent building structure collapse at Kaloor must be a wake-up call to the authorities concerned, the committee formed to inquire into the incident suggested building permits for high rises should be issued only after proper scrutiny of designs and construction procedures by competent engineers.“The committee feels the collapse of the touch pile system of the building should serve as a wake-up call to construction engineers and authorities.
“It’s only purely out of luck no lives were lost in the mishap. There was only one building close by and this has to be razed now. With workers in the excavated area and buildings nearby, it would have been not just a failure but a catastrophe. When the committee called for the papers regarding the permission granted for the earth retaining system and structural design, the sanctioning authority stated no such approval was provided,” the committee said in its report.
“Considering the fact Kochi falls under Zone III of earthquake-prone areas with expected wind speeds of upto 140 kmph and deep soft marine clay deposits, we strongly feel proper scrutiny of designs and construction procedures should be done by competent engineers before building permits are issued. When deep excavations are required for cellar floors, permits should be granted only after checking the stability of earth retaining structure and ensuring the safety of neighbouring buildings,” the report said.
As per the report, the collapse occurred due to the fact that the strut system was inadequate to take up the lateral thrust from touch piles and provide the required stability.
“The soil at dredge line turned out to be very soft and caused considerable weakness of the interface soil. High thrust from the shoring pile at the interface caused the yielding of the soil. “The subsequent increase in the unsupported length of pile is also a reason for the failure of the pile in bending. A second tier of strut system at a lower depth could have been helpful in retaining the touch pile system in position,” the committee stated.
“It is true the cellars are going deeper and deeper and floors going higher and higher. The construction industry is slowly getting attuned to modern design techniques and construction procedures. The trends cannot be discouraged but the authority should exercise greater caution and control when projects with such trends are approved,” the Committee added.
The committee comprised Sheeladevi P D (Deputy Collector, DM), Ushakumari P R (Senior Town Planner - Town Planning, Ernakulam), Krishnendhu (Geologist, Mining and Geology, Ernakulam), Rejina Beevi (Executive Engineer - PWD Buildings), Babu T Jose (Emeritus professor, Cusat) and Anil Joseph (Structural Expert).