南水北调南干渠边坡有限元稳定性分析

Finite element stability analysis on slope of South Main Canal of South to North Water Diversion Project

采用有限元强度折减法,对南水北调南干渠典型断面进行稳定性分析。计算采用邓肯非线性弹性模型,对渠道边坡的实际开挖施工过程进行模拟。以最大水平位移作为失稳判据,建立最大水平位移和折减系数之间关系曲线,得到不同折减系数下土坡应力变形分布规律和边坡安全系数。计算结果表明,有限元强度折减法,能够较真实地考虑土体应力应变关系和施工过程影响,所得边坡稳定系数略大于毕肖普法计算结果,计算断面稳定安全系数满足规范要求。

The strength reduction finite element method was used to analyze the stability of the typical section of the South Main Canal of South to North Water Diversion Project. The Duncan - Chang non-linear constitutive model was employed to describe the stress and strain relationship of the soils. The displacement mutation of the maximal horizontal displacement of the slope was used as a criterion for evaluating the instability. The research results based on the FEM reduction stability analysis was veri-fied by traditional simplified Bishop Method. There is good accordance between both methods, which proved that the analysis is reasonable. And both results fulfil the designation requirement.