摘要
考虑到边坡渐进破坏过程中监测点产生角度变化,提出基于角度倾斜突变的边坡临界状态确定方法。通过FLAC 3D软件建立不同坡高、坡角、宽高比的三维岩质边坡模型,用等效强度参数的Mohr-Coulomb准则代替Hoek-Brown准则进行强度折减计算,绘制坡顶各监测点取不同角度传感器长度时的角度-折减系数关系曲线;鉴于其存在突变特征,采用双曲线方程拟合计算安全系数。结果显示,角度传感器的长度增大,各监测点角度变化灵敏性增强,也可一定程度改善拟合效果。角度-折减系数拟合计算得到的边坡安全系数与FLAC 3D软件求解出的安全系数的相对误差均在5%以内,且与位移突变判据计算的安全系数结果接近,说明基于角度倾斜突变确定边坡临界状态的方法可行。该方法物理意义明确,判断简单,尤其适用于三维边坡。
Considering the angle changes of monitoring points during progressive failure of slopes, a method for determining the critical state based on the mutation of angular tilt is proposed. FLAC 3 D software was used to establish three-dimensional rock slope models with different heights, angles and width-to-height ratios, and the Mohr-Coulomb criterion of equivalent strength parameters was used to replace Hoek-Brown criterion for strength reduction calculations. Then the angle-reduction factor relation curves of different angular sensor lengths at each monitoring point of each slope top monitoring line were drawn. In view of the mutations of these curves, the hyperbolic equations were used to fit them and calculate the safety factors. The results showed that with the increase of the angular sensor length, the sensitivity of the angle variation of each monitoring point was enhanced,and the fitting effect of the angle-reduction factor relation could be improved to some extent. The relative errors of safety factors of all slopes calculated by fitting the angle-reduction factor relations and FLAC 3 D software were within 5%, and they were close to the safety factors calculated by the displacement mutation criterion, indicating that the method of determining the critical state of the slope based on angular tilt mutation is feasible. The method has advantages such as definite physical meaning and easy judgement, and it is especially suitable for three-dimensional slopes.
作者
屈晓英
袁维
谭捍华
黎海滨
王伟
彭澍
QU Xiaoying;YUAN Wei;TAN Hanhua;LI Haibin;WANG Wei;Peng Shu(College of Civil Engineering,Shijiazhuang Tiedao University,050043,Shijiazhuang,China;Hebei Provincial Technical Innovation Center of Safe and Effective Mining of Metal Mines,050043,Shijiazhuang,China;Guizhou Province Quality and Safety Traffic Engineering Monitoring and Inspection Center Co.,Ltd,550000,Guiyang,China;China Railway 18th Bureau Group Co.,Ltd,300222,Tianjin,China)
出处
《应用力学学报》
CAS
CSCD
北大核心
2021年第6期2353-2359,共7页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金青年科学基金资助项目(51709176)
河北省自然科学基金青年科学基金资助项目(E2018210046)
贵州省科技支撑计划(黔科合支撑[2019]2883号)
河北省教育厅重点项目(ZD2020333)。
关键词
角度倾斜突变
临界状态
三维岩质边坡
强度折减计算
安全系数
angular tilt mutation
critical state
three-dimensional rock slope
strength reduction calculation
safety factor
