侧移土体被动桩成拱效应分析

在分析某工业厂房坍塌原因的基础上，认为由于侧移土体被动桩的成拱效应，地面超载引起的土压力被传递到桩身上，导致桩身发生了较大的侧向变形是这起事故发生的主要原因，事故的发生证明了侧移土体被动桩成拱效应的存在。在此基础上，建立了三维数值模型，对土拱效应的形成过程进行了模拟。对三维情况下被动桩的成拱效应与相同条件二维情况的形式和变化规律进行了比较，对不同桩间距、不同堆载大小情况下的被动桩成拱效应进行了分析，并对成拱效应随时间的变化规律进行了探讨。

Soil arching action in passive piles under lateral displaced soil

Based on researching the collapse cause of an industrial building, it is concluded that the main cause is pile foundation’s lateral displacement induced by soil pressure, which is transferred to pile body due to soil arching action between piles. The accident proves that the soil arching action indeed exists between piles. Furthermore, three-dimensional numerical model is established to explore soil arching action of passive piles; the comparison is made for the differences of soil arching action between three dimension and two dimension; the rule is drawn for soil arching action of passive pile under different pile spaces and different loads; and the variation rule of soil arching action with time is explored.