冻胀对基坑悬臂支护桩影响数值模拟研究

Effects of Frost Heaving on the Pile Supporting Sturcture of the Foundation Pit

近年来,随着基坑开挖深度增加,施工工期延长。使得北方地区的某些基坑工程不得不进入越冬期。土体冻胀将影响支护结构的稳定,温度不同,土体冻胀强弱不同。本文运用FLAC3D软件,模拟基坑悬臂桩支护结构,在-2℃,-5℃,-8℃,-10℃,-15℃,-19.5℃,-20℃和-21℃等不同温度作用下,支护结构的变形、水平冻胀力的分布模式及大小的作用规律,结果表明,随温度降低,土体冻深增大,支护结构顶部水平位移增大,水平冻胀力增大,并呈现中间大、两端小的抛物线型分布。

In recent years, with the increase of excavation depth and extension of construction period.Many foundation pits engineering enter into winter period in north area.Frost heaving frost of soil will affect stability of supporting structure, strength different with temperature.In this paper, it used FLAC3D to simulate pile sup-porting structure of foundation pit, with the different temperatures in -2℃ ,-5℃ ,-8℃ ,-10℃ ,-15℃ ,-19.5℃ , -20℃ ,-21℃.In order to study the deformation of the pile structure,the distribution of the horizontal frost heav-ing force model and size.In conclusion,with the decrease of temperature, the frozen depth of soil,horizontal defor-mation of supporting structure and horizontal frost heaving force increased , which appears large in middle and small of both end.