软土深基坑不对等开挖深度的支护结构设计

Supporting Structure for Asymmetric Depth of Foundation Pit in Soft Clay

对于深基坑支护工程,当基坑周边不同位置开挖深度不同时,基坑四周的土压力是不均衡的,围护桩的变形趋势也是不同的。当围护桩出现往坑外位移趋势时,作用在围护桩上的土压力应按被动土压力考虑,而不是主动土压力。当围护桩外侧的被动土压力不足以抵抗支撑力时,会出现坑外土体破坏,特别是软土深基坑。此时应对坑外土体进行加固处理,或者调整支撑体系改变支撑力的传递路线。

With regard to retaining and protecting of deep foundation, the surrounding soil pressure is unbalanced due to the asymmetric depth. Meanwhile, the deformation tendency of retaining pile earth pressure, not active earth pressure is taken into account when the pile has is different as a consequence. Passive displacement toward outside of foundation pit. If passive earth pressure can not resist the braced force, soil mass outside would be destroyed, especially for soft clay pit. At this moment, soil mass outside should be strengthened. As an alternative, adjustment of bracing system can be used to change the route of force.