摘要
滑动机理分析一般采用定性的方法加以描述,尚缺乏合理的量化指标进行刻画。反演分析是确定滑带强度参数的重要手段,一般采用基于整体稳定性系数的刚体极限平衡方法,但这种反演方法无法建立滑动机理与强度参数间的直接联系。本文采用数值计算方法获得滑带单元的应力场和滑动方向,基于Mohr-Coulomb强度准则定义滑带点安全系数为该点抗剪强度与滑动方向剪应力的比值。通过点安全系数的分布判断滑坡的滑动机理,使滑动机理研究定量化,并以点安全系数对滑面面积的加权平均值作为滑坡的整体稳定性系数,建立起滑动机理与整体稳定性系数的联系。在滑带参数反演分析中,需要同时满足滑动机理和整体稳定性系数要求,相应的强度参数才是合理的结果。以万梁高速公路K49滑坡的室内大型地质力学试验模型为例,介绍了基于滑动机理分析的滑坡强度参数反演方法和步骤,论证了方法的合理性。
The mechanism research at present mainly pauses in the qualitative description.The quantitative index is lack in the description of sliding mechanism.Inversion analysis is an important means to determine the strength parameter of sliding zone.Rigid body limit equilibrium method and a global safety factor are used in this paper.So,strength parameter has no direct relation with the sliding mechanism.Three-dimensional stress state and slide direction of the slip layer zone are obtained by numerical computation.Base on the Mohr-Coulomb Strength Criterion,a point safety factor as the ratio of the shear strength of the slip zone to the shear stress parallel to the gliding direction is defined.The safety factor of the landslide as the weighted average value of the zone point safety factor with its zone is defined.The sliding mechanism is studied quantitatively by means of analyzing the distribution of the zone point safety factor.Landslide stability can be evaluated through the safety factor.So a relationship between the sliding mechanism and stability factor is established.In the inversion analysis,the sliding mechanism and stability can be satisfied simultaneously.So the corresponding strength parameter is a reasonable inversion result.This paper uses the example of the large scale geomechanics model test for K49 landslide in Wanliang highway to illustrate the method and procedure for strength parameter inversion of sliding zone based on sliding mechanism analysis.The rationality of this method is shown by the applications.
出处
《工程地质学报》
CSCD
北大核心
2012年第1期15-20,共6页
Journal of Engineering Geology
基金
国家自然科学基金项目(50808149)
中央高校基本科研业务费专项资金(SWJTU09CX007)
西南交通大学竢实之星资助
关键词
滑坡
滑动机理
点安全系数
参数反演
Landslide
Sliding mechanism
Point safety factor
Parameter inversion
