基于反分析的膨胀土基坑边坡侧向土压力分布规律研究

摘要

膨胀土吸水膨胀,会对基坑边坡的支护结构体产生一部分附加土压力,威胁基坑边坡的稳定性.为此,通过现场钢筋应力求得的桩身弯矩,对桩侧土压力的分布和大小进行反分析,得到了某基坑在某次降雨后的膨胀土压力分布规律.结果表明,膨胀土吸水产生的膨胀力随着深度先增大,后减小.膨胀力的大小与膨胀土浸水的大小有关.%The water swelling of expansive soil will produce a part of the additional earth pressure to the support structure of foundation pit slope,threatening the stability of the foundation pit slope.In this paper,the distribution and the size of the pile side earth pressure are back analyzed by the pile bending moment obtained by the stress of the steel bar,and the distribution law of the expansive soil pressure of a foundation pit after a certain rainfall is obtained.The results show that the swelling force of the expansive soil increases with the depth first and then decreases.The expansion force is related to the immersion of the expansive soil.