Impact Analysis of Reservoir Water-level Fluctuation on Building Foundations on Bank Slopes

Reservoir water-level fluctuation can alter the bearing capacity and stability of foundations on bank slopes by changing local seepage and stress fields, thus inducing displacement deformation of building foundations. A 2D saturated– unsaturated seepage model was constructed with ABAQUS for simulation calculation of the bank slope and buildings in the Shanganping Village, Wushan Section of the Three Gorges Reservoir Region, China. This task was conducted to investigate the influencing law of reservoir water-level fluctuation on building foundations on bank slopes and assure their safety. Subsequently, a comparative analysis about the variation laws of underground water and stresses and displacement of building foundations on bank slopes when the reservoir water-level fluctuation rate varies was carried out. Results show that the height ratio of the trailing saturate line at the side slope is 1.19 when the rate of the reservoir water-level rise is 1 and 3 m/d. Such finding indicates that the hysteresis effect of saturation line is highly obvious when the rate of the reservoir water-level rise is high. The maximum difference of effective stresses at the bottom of the pile foundation is 5 KN when a reservoir water-level fluctuation exists. This finding reveals that the reservoir water-level fluctuation will induce great changes to the stress state of building foundations. The maximum displacement of pile foundation is positively related with the rate of reservoir water-level fluctuation. Such a notion reflects that the rate of reservoir water-level fluctuation is a key influencing factor of deformation behaviors of bank slopes and buildings. During a reservoir water-level fluctuation, the settlement value is negatively correlated with the distance between the pile foundation and the frontal edge of the side slope. The error of settlement between the finite element simulation and the theoretical calculation results is lower than 10%, which verifies the accuracy of the numerical simulation in this study. The research conclusions can provide some references to the safety evaluation of existing buildings and design of new buildings on bank slopes © 2020 School of Science, IHU.