Abstract: The Yuxi Hydraulic Regulation Gate is suffering excessing settlement under various loading conditions. The natural conditions, hydraulic, geological tectonic structure, seismic and geotechnical conditions at the site are reviewed. The physical and mechanical properties underneath the gate have been evaluated. The seepage stability is mainly represented by the piping stability. Under the seepage loading conditions, the soil particles, fabric and structures might have deformed and therefore, lead to the seepage related displacement or failure. The evaluation eliminates the potential of liquefaction under the seismic conditions. The scour conditions on the stabilities of the riverbed channel and the hydraulic structures are also important. The foundation remediation plan was proposed based on the stability evaluations. The adopted solutions are: concrete pipe pile installation on the water; seepage path increase and installation of riprap rocks.

Key words: Yuxi Gate, Geological Conditions, Structure Foundations, Remediation Plan