Can you see grass grow? Not by watching for a few minutes but you know it does because it’s higher after a week. It would be tricky to explain this slow occurring event to a jury. A good method to demonstrate it is through time lapse video. But what if it’s something that can’t be filmed?
DJS Associates was recently retained to visually illustrate how water infiltrates concrete slabs and deteriorates structural steel below the surface in an apartment building. DJS utilized photographs and structural drawings to build a to-scale section of the apartment building. Then, through an engineering based animation, DJS demonstrated how water droplets can migrate along a slabs surface, find an entrance, and make its way to unprotected post tensioned cables. Over time, the water can cause the cable to rust. Rust increases the diameter of the cable, putting more stress on the surrounding concrete and often causes the concrete to “pop” or become dislodged near the surface. If left unrepaired long enough, the rust can cause the cable to fail which would compromise the integrity of the concrete slab.
For additional information on DJS Associates’ engineering animations, please contact Hugh Borbidge, BSME or Laurence Penn at experts@forensicDJS.com or via phone at 215-659-2010.