摘要
为确定塑性滑坡变形过程中的安全状态,基于典型的塑性滑坡累计位移-时间曲线,提出采用曲线割线斜率作为滑坡发展阶段的判断标准。对于割线斜率-时间(S_(t)-t)曲线起始段斜率为负,且曲线急剧下降段,可断定为滑坡初始变形阶段;对于缓慢下降段,可认定为匀速变形段;对于总体趋势由负转正并且上升趋势确立的曲线,可将斜率为零的时间点定为滑坡由匀速变形向加速变形转变的临界点;对于加速变形向急剧变形转变的时间点,可采用当次割线斜率与邻近5次割线斜率比确定,采用连续两次割线斜率比第一次大2.0、比第二次大1.0作为滑坡进入急剧变形阶段的控制标准。根据实例,验证了上述方法的可行性和合理性。
A feasible approach of secant slopes was proposed to determine the safety state of plastic landslides,which was based on the typical accumulation displacement-time curve of plastic landslides.The secant slope-time(S_(t)-t)curve was used to determine the stages of landslide deformation.If the S_(t)-t curve was negative and the curve descended steeply,the landslide was judged in the initial deformation stage.The landslide was in the constant deformation stage if the curve’s secant was negative and the curve kept falling slowly;if the curve’s secant was from negative to positive and its upward trend was determined,the time point with zero slope could be defined as the critical point of the transformation for landslides from the constant speed deformation stage to accelerated deformation stage;the ratio of the current secant slope to the secant slope of the near five periods could be used to determine the time point from the accelerated deformation stage to rapid deformation stage.If the ratios were greater than 2.0 for the first time and 1.0 for the second time,the landslide entered the rapid deformation stage.According to the example verification,the feasibility and reasonability of the above method were proved.
作者
王卫中
高德
WANG Weizhong;GAO De(Henan Provincial Communications Planning&Design Institute Co.,Ltd.,Henan Key Engineering Laboratory for Highway Geology Disease Prevention,Zhengzhou 450000,China)
出处
《工业建筑》
CSCD
北大核心
2022年第1期137-142,共6页
Industrial Construction
基金
河南省交通运输科技项目(2020J9)
河南省交通运输科技项目(2019J-2-14)。
关键词
割线斜率比
变形阶段
安全状态
预警
滑坡
secant slope ratio
deformation stage
safety state
early warning
landslide
