输电线路掏挖基础的孔壁稳定性分析及判别  

Stability Analysis on the Undercut Foundation Walls for Transmission Towers

作　　者：曾二贤[1] 冯衡[1] 胡星[1] 王开明[1] 

机构地区：[1]中南电力设计院,武汉市430071

出　　处：《电力建设》2010年第8期17-20,共4页Electric Power Construction

基　　金：中国电力工程顾问集团公司科技项目(DG2-T03-2007)

摘　　要：良好的成孔质量是输电线路掏挖基础适用的重要条件,主要体现在孔壁整体和局部稳定2方面。利用土力学滑动理论求解孔壁土体极限平衡方程,推导出掏挖基础孔壁保持整体稳定需要满足的条件;基于Mohr-Column和Drucker-Prager塑性屈服准则,通过分析掏挖基础成孔前后孔壁土体单元的应力状态,探讨了孔壁的局部自立稳定问题。给出了满足相应稳定条件的临界孔深计算公式及对应的分析判别方法。最后结合工程实例,提出施工建议措施。The good overall and local wall stability is an important precondition for the undercut foundation to be adopted for transmission towers,By using the soil sliding-mechanics theory,the limit balance equation of foundation wall is derived in order to obtain the overall stability conditions of the undercut foundation for transmission towers.Based on the Mohr-Column and Drucker-Prager plastic yield criteria,the stress state of the soil cells of the foundation walls before and after excavation is analyzed,and the wall＇s local self-stability is discussed.The calculation formula for critical foundation depth and relevant analytical methods are put forward.Through some case studies,some useful construction suggestions are proposed for construction.

关 键 词：输电线路 掏挖基础 孔壁 整体稳定 局部破坏 临界孔深 

分 类 号：TM75[电气工程—电力系统及自动化] TU470.3[建筑科学—结构工程]