考虑降雨强度时间模式不确定性的边坡可靠度分析

Slope Reliability Assessment Considering Uncertainty Associated with Rainfall Intensity Temporal Patterns

摘要:

提出了一种考虑降雨强度时间模式不确定性的边坡可靠度分析方法。基于偏度和峰度两参数生成系列反映降雨强度时间模式不确定性的降雨序列，作为边坡渗流?稳定性力学模型的输入，并结合蒙特卡洛模拟计算边坡可靠度。将其应用于浙江地区某概化边坡，评估了降雨强度时间模式对边坡失效概率及失效时间的影响。结果表明：在相同降雨总量和持时下，与后峰型高强度的降雨序列相比，前峰型且相对均匀的降雨序列导致更多的水入渗土体，降低土体强度，使边坡具有更高的失效概率与更短的失效时间，强调了在降雨滑坡灾害预警时需考虑降雨强度时间模式。

Abstract:

A novel approach for slope reliability assessment considering uncertainty associated with rainfall intensity temporal patterns is proposed. Stochastic rainfall sequences considering rainfall intensity temporal patterns are generated based on skewness and kurtosis. These series are incorporated into a coupled seepage–stability model of slope， and Monte Carlo simulation is employed to estimate slope failure probability. The proposed approach is applied to a conceptual slope in Zhejiang Province to evaluate the impact of rainfall intensity time patterns on slope failure probability and failure time. The results show that， under the same total rainfall and duration， early-peaking and relatively uniform rainfall patterns lead to greater infiltration， reduce soil strength， and thus increase the likelihood of slope failure while shortening the time to failure. These findings highlight the importance of incorporating rainfall intensity temporal patterns in landslide early warning systems.