深基坑工程预警系统的初步研究

深基坑支护系统的位移与变形不仅关系到基坑本身的安全问题,也影响到周边环境的安全。针对当前在各行业、地区性规范中,仅依据基坑等级、开挖深度等进行基坑分级,且基坑水平位移允许值不尽相同的实际情况,提出根据土体的安全预警系数预测基坑安全稳定性的新方法。安全预警系数与土体密度、含水率、垂直压力等因素有关,基坑容许位移值与基坑极限位移有关,极限位移值宜采用弹性地基的杆系有限元法求得。

Studies on Predictive System of Deep Foundation Pits

The displacement and the distortion of foundation pit with braced system are related not only to the foundation’s own security,but also to the peripheral environment security.Some industry and regional standard codes of practices classify foundation pits only according to grades and excavation depths,with different tolerances for horizontal displacement.To improve this situation,the authors of the paper proposed a new method to predict the safe stability of the foundation pits according to the safety warning factor of the soil mass.The security early warning factor is related to such factors as soil body density,moisture content,and vertical pressure.Whereas the permissible displacement of foundation pit is related to the limiting displacement,which can be obtained by calculation using elastic foundation finite element method.