非均匀堆载作用下圆形基坑主动土压力分析

基于轴对称情况下土体的极限平衡理论,将圆形基坑主动土压力的滑移线解推广到非均匀堆载情况.通过分析得出基坑半径和土体参数对基坑主动土压力的影响规律,并发现与朗肯土压力理论一致.比较了非均匀和均匀堆载作用下的滑移线场和相应的土压力分布,发现基坑周围不同位置的堆载大小只影响基坑侧壁某部分深度范围内的土压力分布.因此,可根据基坑周围堆载的分布形式,定性估计得到基坑侧壁的土压力分布.

The Active Earth Pressure of Circular Pit Subjected to Non-Uniform Surcharge Loading

Based on the limit equilibrium theory for axially symmetric condition,the active earth pressure of circular pit obtained with slip-line method was extended to non-uniform surcharge loading.By analyzing the influence of the radius of pit and soil parameters to the active earth pressure distribution,it was(achieved) that the influence is identical to Rankine theory.The comparison of slip-line field and active earth pressure distribution under non-uniform and uniform surcharge loading was made,it is shown that the surcharge loading at some region only affects the earth pressure at some specific area.So,it is easy to estimate earth pressure distribution qualitatively according to the distribution of surcharge loading.