土钉墙的一种可靠性自动优化设计法  

OPTIMAL DESIGN METHOD OF RELIABILITY FOR SOIL NAILED WALLS

作　　者：朱彦鹏[1] 王秀丽[1] 李忠[1] 罗锦添[2] 

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050 [2]Carleton大学

出　　处：《岩石力学与工程学报》2006年第z1期3123-3130,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：教育部春晖计划资助项目(Z2004-1-62011)

摘　　要：建议一种土钉墙设计的可靠性优化设计法,这种方法能够确保土钉墙在施工开挖和使用过程的全过程安全,即:(1)能够保证施工开挖过程和使用阶段的土钉承载力的强度要求;(2)能够保证土钉墙施工每个开挖阶段和使用当中的整体稳定性的要求;(3)采用一种迭代优化法使土钉墙结构所用的土钉长度和直径达到最经济。这种方法可考虑土钉对稳定性的影响,建立各个施工开挖阶段和使用过程土钉墙的最危险滑移面的确切位置与每层土钉长度和直径的动态关系。最后,用一案例说明这种方法在各个施工开挖阶段和使用当中的可靠性。该案例是位于湿陷性黄土地区的一深基坑,按照普通土钉墙设计方法在施工阶段出现了破坏。破坏原因分析证明,传统设计方法存在一些缺陷,这个缺陷就是设计中没有建立各个施工开挖阶段土钉墙最危险滑移面与每层土钉长度和直径的动态的变化关系,没有考虑施工开挖阶段的稳定性设计验算问题。采用该方法重新设计基坑施工过程和使用当中均安全可靠,此方法可供土钉墙设计和施工人员参考。An optimal design method of reliability for soil nailed walls is proposed.This method can ensure the safety of the soil nailed wall in excavation and operation,such as:(1) there is enough bearing capacity of the nail head for each excavation stage and in operation,and the yield strength of the steel bar for the nail is not exceeded,(2) there is sufficient safety factor of the slope stability of soil nailed wall for each excavation stage,and(3) an optimal design method based on iteration process is adopted that the most economic design of the soil length and steel bar diameter are achieved.This method incorporates the dynamic relationship between the location of the slip surface,the nail length and the diameter of the steel bar in each excavation stage and operation.The method is applied to a case record for illustration of its capability.The case record involves a failed soil nailed wall in the loess deposit in China.The cause of failure was analyzed,which reveals some deficiency of the existing method of design which doesn′t consider dynamic relationship between the location of the slip surface,the nail length and the diameter of the steel bar and the stability in each excavation stage.The wall is redesigned based on the proposed method and has been constructed successfully.The proposed method can be a useful reference for engineers in design and construction of the soil nailed wall.

关 键 词：土力学 土钉墙 边坡稳定性 可靠性 优化设计 最危险滑移面 动态关系 案例 

分 类 号：TU43[建筑科学—岩土工程]