泥质灰岩高边坡稳定性评价及影响因素研究

Stability Evaluation and Influencing Factors of Argillaceous Limestone High Slope

泥质灰岩容易发生岩溶和风化,导致岩体结构变化和力学强度降低,引起高边坡发生失稳,文中强度折减法理论,将特征位置的位移突变与塑性区的贯通相结合作为边坡失稳的破坏标准,采用FLAC3D软件模拟研究降雨强度、降雨时间,以及边坡开挖对边坡稳定性的影响.结果表明:不同降雨强度下安全系数分别为1.138、1.124、1.109、1.083和0.961;不同降雨时间下安全系数分别为1.109、1.097、1.067、1.034和0.917;不同开挖阶段安全系数分别为1.173、1.148、1.126、1.064和0.962.边坡失稳时,塑性区贯通,坡顶水平位移无限增大,坡脚为边坡危险点位置,需要对边坡进行支护加固,并且做好边坡排水.

Shaly limestone is prone to karst and weathering, which leads to the change of rock mass structure and the decrease of mechanical strength, and leads to the instability of high slope. Based on the strength reduction theory, the combination of the sudden change of displacement at the characteristic position and the penetration of plastic zone was taken as the failure standard of slope instability, and the influence of rainfall intensity, rainfall time and slope excavation on slope stability was simulated by FLAC3 D software. The results show that the safety factors under different rainfall intensities are 1.138, 1.124, 1.109, 1.083 and 0.961 respectively. The safety factors under different rainfall time are 1.109, 1.097, 1.067, 1.034 and 0.917 respectively. The safety factors in different excavation stages are 1.173, 1.148, 1.126, 1.064 and 0.962 respectively. When the slope is unstable, the plastic zone runs through, the horizontal displacement at the top of the slope increases infinitely, and the foot of the slope is the dangerous point of the slope, so it is necessary to support and reinforce the slope, and do a good job in slope drainage.