Foundation Rebound at Dos Amigos Pumping Plant

In a deep excavation, the subsoils rebound or heave as a function of depth, soil properties, and environment. To date, foundation rebound cannot be predicted from laboratory tests with confidence. The construction of Dos Amigos Pumping Plant provided an opportunity to gain more knowledge about rebound from a deep excavation. Reference points were installed in the foundation soil prior to excavation so rebound could be measured during and after excavation. The measured rebound is compared to the calculated rebound based on laboratory tests. It was found that the measured total rebound compared favorably with the calculated rebound based on laboratory testing. However, if the calculated rebound is adjusted for time, the correlation is poor.