基坑土钉支护稳定分析方法及其应用

探讨一种土钉支护边坡稳定分析方法，为设计提供较为科学合理的分析手段。基于土坡稳定分析常用的瑞典条分法，考虑土钉的极限拉力作用，建立稳定安全系数公式，可用于基坑土钉支护设计。提出用几何控制多数确定最危险滑动面的计算机算法，通过计算表明：安全系数是几何控制参数的单峰函数。用黄金分割法分步对几何控制多数进行优化，提高了计算速度。通过与国外方法比较和工程实例验算，确定安全系数的取值范围，一般工程安全系数应为１．２－１．５。具有较后的工程应用价值。

A STABILITY ANALYSIS METHOD AND ITS APPLICATIONFOR SOIL NAILING IN EXCAVATION

A method is proposed for the stability analysis of soil-nailed support system for deep excavations,This method is based on the Fellenius method of slices with the limit tensile force in the nails being included in estimating the safety factor,Novel idea is applied to define the position of the trial slip surface by a few properly chosen geometric parameters,The calculated safety factor for different slip surfaces is found to be a single-perked function of the aforementioned geometric parameters, which facilitates an efficient search of the critical slip surface by using the optimization technique of golden section.Several engineering projects are analyzed by the proposed method,and the results are compared with those obtained by the Davis method,the modified Davis method,the french method and the kinematical method.Similarities and dissimilarities among them are discussed and judeged by engineering experience,It is concluded through these calcultions that acceptable magnitude of safety factor should lie between 1.2-1.5 for ordinary projects analyzed by the proposed method.