土质边坡滑坡灾害的分级预警判据

Grading early warning criteria for landslide on earth slope

为解决同一土质边坡在不同变形阶段的形变规律不同,单一预警指标无法表达土质边坡在整个变形过程中的动态变形特征问题,以角位移场、边坡宏观变形迹象、安全系数为预警指标,提出土质边坡滑坡灾害分级预警方法,基于室外模型试验建立各边坡剖面在不同变形阶段内的角位移场,采用Levenberg-Marquardt优化算法拟合同一场内的角位移,构造动态分级预警阈值表达式;结合现场调研和相关规范,分别提炼以边坡宏观变形迹象、安全系数为指标的标准阈值;建立以角位移场、边坡宏观变形迹象、安全系数为预警指标,以蓝色(注意级预警)、黄色(警示级预警)、橙色(警戒级预警)、红色(警报级预警)的土质边坡滑坡灾害四级预警机制,充分利用多源信息,实现边坡失稳的及时有效预警,实现土质边坡稳定性变化发展的动态管控。

To address the issue that the deformation patterns of the same soil slope in different deformation stages are different,and a single warning indicator cannot express the dynamic deformation characteristics of the soil slope throughout the entire deformation process,a classification warning method for landslides in soil slopes is proposed.The angle displacement field,macroscopic deformation signs of the slope,and safety factor are selected as warning indicators.The method is based on outdoor model experiments to establish the angle displacement field of each slope profile in different deformation stages,fitting the angle displacements within the same field using the Levenberg-Marquardt optimization algorithm.Dynamic classification warning threshold expressions is constructed.Field investigations and relevant regulations are combined to extract standard thresholds based on macroscopic deformation signs of the slope and safety factors separately.A four-level warning mechanism for landslides in soil slopes is established with angle displacement,macroscopic deformation signs of the slope,and safety factor as warning indicators,using blue for attention level warning,yellow for caution level warning,orange for alert level warning,and red for alarm level warning.Multiple sources of information are fully utilized to achieve timely and effective warning of slope instability to realize dynamic control of the development of soil slope stability changes.