Effects of soil reinforcement at bottom of foundation pits on deformation characteristics of retaining walls under eccentric loads

Based on the typical ramp foundation pit project at West Wenyi Road in Hangzhou, the influences of eccentric pressures on the deformation of diaphragm walls of the foundation pit are investigated by using the finite element method, and the control effects of soil reinforcement at the bottom on the deformation of diaphragm walls under different eccentric pressures are analyzed. The results show that with the increase of the eccentric loads or the width of the eccentric loads, the diaphragm walls at the eccentric and non-eccentric sides shift to the inner and outer sides of the foundation pit, respectively, and the position of the eccentric loads only affects the overall torsional deformation trend of the diaphragm walls. The soil reinforcement at the bottom of the pit has an obvious effect on the deformation control of the diaphragm walls. Under different eccentric pressures, with the increase of the reinforcement depth, the diaphragm walls at both sides shows a trend of shifting to the outer and inner sides of the pit, respectively, and the absolute value of the maximum lateral displacement decreases gradually and then tends to be constant. When the eccentric loads are far from the foundation pit or the width of the eccentric loads is large, the absolute value of the maximum lateral displacement of the diaphragm walls at the non-eccentric side decreases first and then increases, indicating that the soil reinforcement can effectively reduce the maximum lateral displacement of the diaphragm walls and significantly reverse their counterclockwise deformation trend.