降雨条件下花岗岩残积土填方边坡的稳定性预测及失稳灾害控制

The granite residual soil is widely employed as fill materials to construct embankments and slopes in Southeast China where such materials are abundant. However, as the unsaturated properties of such fill materials under rainfall infiltration are not well understood and the uncertainties associated with the stability analysis of fill slopes made up of granite residual soils (FSMGRS) are not adequately characterized, the design, construction and maintenance of such slopes is in an environment with unclear uncertainties. This project starts with laboratory investigation of the unsaturated properties of the compacted granite residual soil. Then, the spatial variability of the unsaturated soil properties of the compacted residual soil is characterized and modeled with a multivariate random field model. A probabilistic model is then constructed to evaluate the stability of FSMGRS based on random field modeling of the unsaturated soil properties. Finally, by adjusting the easy-to-control factors, the effect of noise factors which are hard to control on the uncertain performance of the slope is minimized, based on which a robust method for stability control of the slope is proposed. This project will provide the fundamental theory and well as design method for realistic stability prediction as well as hazard control of FSMGRS under rainfall infiltration.

我国东南沿海地区存在大量处于非饱和状态的花岗岩残积土填方边坡。由于对降雨条件下非饱和花岗岩残积土填土的力学特性尚不清楚，对其稳定性预测中存在的不确定性因素缺乏认识和考虑，许多花岗岩残积土填方边坡在其稳定性未被充分认知的情况下进行设计、施工和服役，埋下了严重的安全隐患。本项目以降雨条件下的花岗岩残积土填方边坡为研究对象，通过力学特性试验、模型试验、理论研究和数值分析相结合的方法，明确花岗岩残积土填土在饱水过程中的渗透特性和强度软化规律，揭示花岗岩残积土填方边坡在降雨条件下的失稳机理，研究花岗岩残积土填土力学参数的空间变异性规律，基于多维相关随机场模型对降雨条件下花岗岩残积土填方边坡的稳定性进行预测，利用鲁棒性原理对其失稳灾害进行控制，为降雨条件下花岗岩残积土填方边坡的稳定性预测和灾害控制提供理论依据和技术支持。

我国东南沿海地区存在大量处于非饱和状态的花岗岩残积土填方边坡。由于对降雨条件下非饱和花岗岩残积土填土的力学特性尚不清楚，对其稳定性预测中存在的不确定性因素缺乏认识和考虑，许多花岗岩残积土填方边坡在其稳定性未被充分认知的情况下进行设计、施工和服役，埋下了严重的安全隐患。本项目以降雨条件下的花岗岩残积土填方边坡为研究对象，通过试验、理论研究和数值分析相结合的方法，明确了花岗岩残积土填土的水力特性和强度特征，揭示了花岗岩残积土填方边坡在降雨条件下的失稳机理，研究了花岗岩残积土填土力学参数的空间变异性规律，基于多维相关随机场模型对降雨条件下花岗岩残积土填方边坡的稳定性进行预测，提出了基于鲁棒性原理的边坡加固有效性评价方法，为降雨条件下花岗岩残积土填方边坡的稳定性预测和灾害控制提供了理论依据和技术支持。