合肥膨胀土基坑工程事故分析与预防

Analysis and Prevention of Foundation Pit Accidents in Hefei District

围绕发生在合肥地区的基坑工程事故,对膨胀土基坑边坡的稳定性进行了多方面的分析。膨胀土基坑在开挖卸荷、干湿交替等外界因素作用下,土体的强度会急剧降低,基坑边坡的稳定性急剧下降。由于土体内具有大量裂隙,膨胀土基坑边坡的破坏由表层浅部土块的滑裂变形开始逐渐向深部发展。针对膨胀土基坑的破坏特点,提出了从认识强度参数、加强防水措施和规范施工程序等三个方面来预防基坑事故的发生,对合肥地区膨胀土基坑的设计和施工提供一定的指导和帮助。

In view of the foundation pit accidents in Hefei expansive soil district,this paper sets an all-round analysis of the expansive soil slope stability.During excavating,when the humidity alters,the soil strength reduces greatly and the pit slope stability declines.Because there are many cracks,the expansive soil pit slope fails from the slipping of local mass closing the earth surface.Whereas the failure attributes of pit slopes in expansive soil,three ways are put forward to prevent the accidents.The ways include deepening the understanding of soil strength parameters,reinforcing waterproof measures and improving site management.This paper can play as a reference and is helpful for foundation pit retaining design and site management.