基于可靠度的框架预应力锚杆加固边坡地震稳定性分析

In recent years, the reinforcement technology of frame with pre-stressed anchors was applied more and more widely in slope engineering, the seismic stability analysis of the reinforced slope was also developed gradually. However, in the stability analysis, it is obviously unreasonable that the unknown and uncertain factors such as soil parameters have been attributed to a certain safety coefficient. Based on the reliability analysis method, the probability density function and distribution map considering both fuzziness and randomness is explored, the influence of uncertain factors contains soil parameters, anchor prestress, seismic action on the stability of slope reinforced is clear,and the reliability analysis model of slope reinforced by frame with pre-stressed anchors is proposed, then the methods to seismic stability analysis and evaluation based on the reliability theory is given. Then, the seismic resistance stability analysis of slope reinforced by frame with pre-stressed anchors is really achieved, and the earthquake damage characteristics of slope reinforced by frame with pre-stressed anchors are revealed. Hence, the earthquake disaster mitigation control measures are proposed. The results of this researth can be applied to the deep excavation cutting reinforced slope engineering. The researth can enhance the theory of seismic resistance and disaster mitigation control, and can be valuable to the seismic resistance for deep excavation cutting reinforced slope engineering.

近年来，框架预应力锚杆加固技术在边坡工程中的应用日益广泛，框架预应力锚杆加固边坡的地震稳定性分析也得到了一定的发展，而稳定性分析中把土体参数等未知的和不确定的因素用一个确定的安全系数来反映，显然是不合理的。本项目基于可靠度分析方法，探索同时考虑模糊性与随机性的土体力学参数的概率密度函数及其分布图，明确土体参数、锚杆预应力和地震作用等不确定因素对框架预应力锚杆加固边坡稳定性的影响，建立适用于框架预应力锚杆加固边坡的可靠度分析模型，提出基于可靠度的框架预应力锚杆加固边坡地震稳定性分析方法及评价方法，实现真正意义上的框架预应力锚杆加固边坡的抗震稳定性分析，揭示框架预应力锚杆加固边坡的地震破坏特性，进而提出相应的地震减灾控制措施，并将研究成果应用于深挖路堑加固边坡工程。研究成果将丰富框架预应力锚杆加固边坡的抗震减灾控制理论，对深挖路堑加固边坡工程抗震有重要的实用价值。

针对框架预应力锚杆加固边坡稳定性分析中存在土体力学参数不确定性、地震作用不确定性、锚杆失效不确定性的问题，建立了土体物理力学参数模糊随机处理模型，提出了考虑土体参数模糊随机性与边坡模糊过渡区间的框架锚杆加固边坡可靠度计算方法；同时，在框架预应力锚杆加固可靠度分析中，将地震作用视为随机变量，进行了地震作用下的框架预应力锚杆加固边坡可靠度分析；最后，为分析局部锚杆失效对加固边坡可靠度的影响，建立了单根锚杆失效状态下框架预应力锚杆加固边坡可靠度分析。通过以上研究，丰富了框架预应力锚杆加固边坡地震稳定性设计与分析方法，揭示了边坡工程中的不确定性因素对框架预应力锚杆加固边坡在静力与动力状态下破坏特性，此外，研究成果将运用到深挖路堑加固边坡的动力、静力稳定性分析中，补充完善框架预应力锚杆加固边坡的静力与动力可靠度分析理论。