| 物质点强度折减法边坡失稳判据选择方法 |
| |
| 引用本文： | 蒋先平,张鹏,卢艺伟,刘磊磊,张明辉.物质点强度折减法边坡失稳判据选择方法[J].地质科技通报,2022,41(2):113-122. |
| |
| 作者姓名： | 蒋先平 张鹏 卢艺伟 刘磊磊 张明辉 |
| |
| 基金项目： | 国家自然科学基金青年基金项目41902291湖南省自然科学基金项目2020JJ5704中南大学中央高校基本科研业务费专项资金项目2021zzts0810 |
| |
| 摘 要： | 用物质点强度折减法求解边坡安全系数时, 需要选择一定的失稳判据, 而采用不同的失稳判据获得的安全系数通常存在一定差异。为此, 采用物质点强度折减法对两个边坡算例进行了稳定性分析, 对比研究了文献中常用的4种边坡失稳判据(计算不收敛、特征点位移突变、塑性应变贯通及界限值判据)在计算边坡安全系数时的合理性及适用性。同时, 将Spencer极限平衡法获得的安全系数作为参考, 进一步验证了结果的合理性与准确性。结果表明: ①数值计算的收敛性不能作为边坡失稳判据; ②将特征点位移突变视为边坡失稳判据时, 获得的安全系数与极限平衡法获得的结果基本一致, 故特征点位移突变可以作为边坡失稳判据; ③塑性应变贯通和边坡最大位移随迭代时间步趋于稳定的界限值不宜单独作为边坡失稳判据。
|
| 关 键 词： | 边坡稳定性分析 物质点法 强度折减法 失稳判据 安全系数 |
| 收稿时间： | 2021-04-07 |
Slope failure criterion for the strength reduction material point method |
| |
| Abstract: | It is necessary to select an instability criterion for the material point strength reduction method (SRMPM) to solve the slope safety factor (Fs), and there are some differences in the obtained Fs values with different instability criteria. To examine the rationality and applicability of the four common instability criteria (i.e., calculation nonconvergence, displacement mutation of the feature point, transfixion of the plastic zone and the limit value), this paper uses the SRMPM to analyse the stability of two slope examples. The Fs obtained by the Spencer limit equilibrium method (LEM) is taken as a reference to further verify the rationality and accuracy of the results. The results show that ① the material point calculation is convergent, so the calculation nonconvergence cannot be used as the slope instability criterion; ② when the displacement mutation of the feature is regarded as the criterion of slope instability, the Fs is basically consistent with the LEM, so the displacement mutation of the feature point can be used as the slope instability criterion; and ③ the limit value and the transfixion of the plastic zone cannot be used alone as the slope instability criterion. |
| |
| Keywords: | |
|
| 点击此处可从《地质科技通报》浏览原始摘要信息 |
| 点击此处可从《地质科技通报》下载免费的PDF全文 |
|
