滑移型岸坡失稳机理及计算方法研究

Study on the failure mechanism and calculation method of slip style slope instability

滑移型岸坡失稳规模大、危害性强,针对其失稳的特点,阐明了其破坏均是沿结构面滑动,因此,在稳定计算中应该考虑软弱结构面的影响,该类型的破坏为典型的折线型滑动,在此基础上提出滑移型岸坡失稳计算应该采用自动优化法搜索最优任意滑裂面,并使得滑裂面尽可能穿过软弱结构面。采用提出的计算方法对某实际工程典型断面进行了稳定分析,并研究了水位的升降与D型排处理对滑移型岸坡稳定的影响。研究成果表明:滑移型岸坡失稳的主要控制因素在于软弱结构面的强度参数较低,水位的升降就可引起该类型的岸坡滑移破坏,造成大面积滑坡,仅采用D型排处理滑移型岸坡失稳是不可行的,建议采取表面抗冲刷与阻止其沿软弱层滑动的共同措施。

Slip style slope instability is large in scale and has strong harmfulness. Aiming at the instability characteristics,it is explained that its failure is sliding along the structure plane,so the effect of weak structure surface should be considered in the stability calculation,and the type of failure is typical mansard sliding. Be based on that it is presented that the stability calculation method should adopt automatic optimization method to search the optimal arbitrary slip surface,and make the sliding surface as much as possible pass through the weak structure plane. The stability analysis of typical section for a practical engineering is carried out by using this method,and the effect of rising and falling of water level and D style soft mattress treatment on slip style slope stability are studied. The results show that the main control factors of the slip style slope instability lie in the low intensity parameter of weak structural plane,and even the rising and falling of water level can cause this type of slope sliding failure,which could result in a large landslide.Only using D style soft mattress treatment to handle the slip style slope instability is not feasible. It is suggested that the common measures of surface anti-scouring and preventing the sliding along the weak layer should be adopted.