黄土地区框架预应力锚杆支护结构设计参数的灵敏度分析

SENSITIVITY ANALYSIS OF DESIGN PARAMETERS OF GRILLAGE SUPPORTING STRUCTURE WITH PRESTRESSED ANCHOR IN LOESS REGION

灵敏度分析是土木工程中解决多参数辨识问题的一个主要方法。结合黄土地区十余个深基坑和边坡工程实例,在考虑框架、锚杆对土体边坡稳定性影响的情况下,基于圆弧滑动条分法和网格法建立黄土地区框架预应力锚杆支护结构的内部整体稳定性安全系数计算模型,并利用全局差分法建立其灵敏度分析模型,研究安全系数及其灵敏度与各设计参数之间的变化关系,得到一些具有参考价值的分析结果,为框架预应力锚杆支护结构设计提供具有指导意义的初始参数取值范围,从而为其优化设计提供重要依据,对黄土地区深基坑工程框架预应力锚杆支护结构的设计和施工具有一定的参考价值。工程实践表明文中分析的实用性。

Sensitivity analyses have been considered to be one main method in the solution to identification of many parameters in civil engineering.Based on more than ten examples of deep excavation and slope engineering in loess region,considering the effects of grillage and anchor on the stability of soil slope,the model for internal global safety factor of grillage supporting structure with prestressed anchor in loess region is established by using circular slice and mesh methods.The model for its sensitivity analysis is also established by the global finite-difference method.The relationships among safety factor,design parameters,sensitivity and design parameters are analyzedf,rom which some valuable results are obtained.The range of preliminary values are given to guide optimum design of grillage supporting structure with prestressed anchor in loess region,which provides some valuable references to the design and construction of this kind of supporting structure.It is proven to be practicable in projects.