基于模型试验的滑体不同节理组合岩块破碎特征研究  

Model experimental study on fragmentation characteristics of rock blocks with different joint combinations

作　　者：杨鹏 郑光[1] 刘建强 黄金成 刘震东 陈明浩 YANG Peng;ZHENG Guang;LIU Jianqiang;HUANG Jincheng;LIU Zhendong;CHEN Minghao(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059

出　　处：《人民长江》2023年第11期166-174,共9页Yangtze River

基　　金：国家重点研发计划项目(2021YFC300040101)。

摘　　要：岩块破碎在高速远程滑坡碎屑化运动中起关键作用,而岩块内在结构控制着滑体的变形、破坏特征和运动距离。为研究不同节理设置对岩块在自重作用下的失稳停积是否会产生不同的破碎效果和运动距离,开展了物理模型试验。试验中通过改变节理方向和组合形式设置了8种不同组合的滑块,其在自重作用下失稳下滑,利用高速摄像机记录试块撞击底板破碎和停积的过程,分析试块撞击底板时的破碎模式;通过人工测量方法获取最远运动距离和堆积体累积质量曲线,并引入相对破碎率对最后试块的破碎程度进行量化;利用由图像处理方法获取的运动参数推导出破碎耗能比,进而研究破碎特征与运动距离、破碎耗能比之间的关系。结果表明:(1)根据滑块的接触方式可将破坏模式分为:撞击破碎、二次碰撞破碎以及滑动摩擦破碎;(2)存在竖向节理、水平向和竖向组合型节理时,滑块的破碎程度和运动距离明显增加;(3)最远运动距离、破碎耗能比都具有随相对破碎率增加而增加的趋势。Rock fragmentation plays a pivotal role in the debris process of high-speed remote landslides.The internal structure of the rock block controls the characteristics of deformation and destruction as well as the run-out distance of the sliding body.To investigate whether different joint settings produce different fragmentation effects,runout distances and depositing of rock accumulation under dead weight effect,we carried out physical model test in this paper.Based on the test,we consider the effect of horizontal,vertical,transverse joints and combination of joints on the slider instability-accumulation process.By varying the joint orientation and combination form,eight different combinations of sliders were set up to slide down under dead weight.The crushing and accumulation of the test blocks as hitting the floor was recorded by a high-speed camera.The pattern of the crushing as the test block hits the floor was analyzed.The deposition distance and accumulation mass curves were obtained by manual measurements,and a relative break-up rate was introduced to quantify the degree of break-up of the residue test block.The energy consumption ratio of the fragmentation is induced by the motion parameters obtained from the image processing method,and then the relationship between the characteristics of fragmentation,the run-out distance,and the energy consumption ratio is investigated.The results show that:①According to the contact mode of the slider,the failure models are divided into impact crushing,secondary impact crushing and sliding friction crushing;②In the presence of vertical joints,horizontal and vertical combined joints,the fragmentation degree and movement distance of the slider increase significantly;③The run-out distance and the dissipation ratio of energy all show an increasing trend with the increase of relative crushing rate.

关 键 词：高速远程滑坡 节理组合 破碎特征 运动距离 物理模型 

分 类 号：TU45[建筑科学—岩土工程]