Structural engineers have compiled the probable sequence and speculated over the initial trigger of the fatal collapse of the 12 story Champlain Towers in Surfside Florida. The fatal collapse has claimed a dozen lives and left 149 individuals unaccounted for. Allyn Kilsheimer, a veteran engineer and founder of KCE Structural Engineers, has been hired by Surfside to investigate the collapse. The investigation into the collapse will likely take months and may never find a single definitive cause.
It has been reported that in October 2018 an engineer, Frank P. Morabito, had discovered “major structural damage” to a concrete slab below the pool deck in the section of the Champlain Towers South condominium building. Morabito stated that waterproofing below the pool deck and entrance drive had failed, allowing for damaging leaks and limited water drainage. Utilizing this information, a surveillance video, photos, and the original 1979 plans, structural engineers are beginning to piece together this disastrous collapse.
While examining images of destruction experts observed indications of “punching shear failure,” in the parking garage below the building. Punching shear failure of foundation, defined by Neenu S K editor of The Constructor, occurs when there is a localized force acting on the structure. It is mostly found in foundations but also common in flat slabs. When the total shear force exceeds the shear resistance of the slab, the slab will be pushed down around the column, or this can be viewed as the column being punched through the slab.
“There is a possibility that part of the pool [area] came down first and then dragged the middle of the building with it, and that made that collapse, and then once the middle of the building collapsed, number two, then the rest of the building didn’t know how to stand up and it fell down also, number three.”stated Kilsheimer
The president of the Structural Engineering Institute of the American Society of Civil Engineers, Joe DiPompeo expressed his beliefs that there must be “a very specific sequence of events that somehow evaded all the fail-safes in the code and everything else.”