摘要
针对均质边坡在不同坡角情况下的确定性模型,借助有限单元法,利用强度折减技术分析边坡整体稳定性,详细分析了有限元计算模型节点第一主应力最大值(σmax)随折减系数(F)的变化规律以及受坡角变化的影响态势。研究表明:σmax随F的增长,常呈平稳、渐增及突降3个阶段,最终当F达到某一值时有限元计算将不收敛,σmax-F曲线中的峰值点对应的F值与传统方法计算的安全系数更为接近,而有限元计算不收敛时对应的折减系数值则往往大于传统方法的计算结果;由于不同工程土性参数或者坡角、坡高等的差异,上述的峰值点有可能被淹没,即有限元计算不收敛之前不会出现。因此,建议在出现峰值点的情况下选用峰值点对应的折减系数作为安全系数,而不出现峰值点时,以有限元计算不收敛作为安全系数的取值判据。
A homogeneous slope is studied in this paper, the maximum of nodes＇ 1st principal stress （σMAx） and its relationships with the critical strength reduction factor （F） and the changeable slope angle are analyzed through finite elements method using the strength reduction technique. The result shows that there are increase phase and decrease phase in the σMAX-F. And the critical strength reduction factor corresponding to the jump point between the upper two phases tends to be good agreement with the solution given by traditional methods. And the jump point may disappear in different slope projects with different strength parameters, slope angle etc. We advise the safety factor be defined to be corresponding to the strength reduction factor of the jump point in the σMAX-F curve when there is one; or to be corresponding to the factor when the numerical non-convergence occurs.
出处
《水运工程》
北大核心
2008年第8期48-51,共4页
Port & Waterway Engineering
关键词
边坡稳定
有限元
安全系数
slope stability
finite elements
safety factor
