大岩淌堆积体滑坡滑带渐进破坏传播的确定性预警方法

DETERMINATION WARNING METHOD FOR PROGRESSIVE FAILUREPROPAGATION OF SLIDING ZONE OF DAYANTANG TALUS LANDSLIDE

以大岩淌堆积体滑坡为例,提出一种预警渐进破坏传播的确定性方法,其创新在于能定量预警滑带破坏传播的全过程,包括破坏传播的方向和速度,破坏的相应日期以及滑坡的破坏程度。首先,系统地介绍滑带点破坏、线破坏和面破坏的传播特性,阐述剪切荷载作用下点破坏传播的全过程曲线,这种相对变形-时间关系全过程曲线类似于试验室刚性伺服压力机上的σ-ε关系曲线;发现线破坏自滑带下盘开始,铅直方向依次自下而上向上盘传播,水平方向自滑坡前缘逐渐向滑坡后部传播的特性;其次,主要从滑带的层状结构、岩层岩性、岩层力学特性及岩体破坏一般原理4个方面阐述铅垂方向破坏传播特性的机制;第三,在上述破坏机制的基础上提出堆积体滑坡滑带渐进破坏传播确定性的预警方法(PFPW),PFPW预警方法以滑带相对变形过程线分析为基础,以其时间过程线的峰值作为点破坏标准,以预警渐进破坏过程中不同破坏阶段为目标,使得通报和预报滑带破坏发生的时间、位置、程度以及破坏传播的速度都能容易而有效地进行。

A new determination warning method for progressive failure propagation of sliding zone on talus landslide is proposed.The new method is able to quantitatively forecast the whole process of sliding failure propagation,including direction and velocity of sliding failure propagation,the corresponding date of the sliding failure,as well as the extent of landslide failure.Firstly,the properties of failure propagation for single-point failure,linear failure and planar failure on sliding zone are systematically presented.The complete relative deformation-time process curves on single-point failure propagation under shearing load are obtained.The curves mentioned above are similar to complete stress-strain process curves obtained with stiff and servo-controled loading testing machine.It is discovered that sliding failure is at the beginning of bottom wall,and then successively from bottom wall up to top wall in vertical direction,and from front to back side of landslide in horizontal direction.Secondly,those mechanisms of failure propagation properties are illustrated mainly in four respects,including stratification of sliding zone,lithological character of formations,mechanical properties of formations,and general principles of rock mechanics.Thirdly,according to those mechanisms,a new quantitative warningmethod（PFPW） is established,which is based on the analysis of relative deformation process curves on sliding zone.The standard of the failure is peak value of change curves of relative deformation and time.The objective of warning is to forecast each failure phase for progressive failure propagation.Based on the results,it is convenient to forecast the date,position and extent of failure,as well as velocity of propagation.