摘要
地下空间开发引发了大量的补偿基础问题,同时也带来了新的岩土技术难题。对结构荷载已完全被开挖土重所替代的等补偿和超补偿基础而言,理论上基础将不会出现工后沉降,但大量实测数据表明,等补偿甚至超补偿基础往往在竣工后均出现沉降变形,南京地铁隧道基础便是典型实例。为此,探讨了深基础与浅基础间的异同点,并推导出考虑埋深的坑底土体应力计算方法;然后围绕基础的整个施工过程,详细分析了开挖卸荷和施工找平对基底变形的影响,发现找平过程中多挖了与隆起量体积相等的土体,而该缺失的土体将导致基础后期发生沉降变形。据此思路计算地铁隧道基础的变形量,并与工程实测数据进行对比,结果表明两者吻合较好,可为今后类似工程的分析提供参考。
A larger number of compensated foundations has appeared by the development of underground space. Meanwhile, some thorny problems of geo-technology are tuned out. Theoretically, settlement of a new construction which foundation form is compensated foundation or exceed-compensated foundation will not occure. But many measured data used to show that buildings with compensated foundation even ex- ceed-compensated foundation also have settlement deformation after completion. Such as the foundation of subway tunnel of Nanjing. Identical and different features between deep and shallow foundations were compared, and calculation method for stress of foundation soil was derived. The influences of excavation unloading and leveling on deformation of basement were analyzed. It is shown that the uplift soil caused by rebound deformation at the bottom of pit is dug which makes the settlement of foundation. The deforma- tion of the foundation of this subway tunnel was calculated by the method mentioned above. It is shown that the results are much closed to measured data when they are compared each other. This method pro- vides a reference to similar projects.
出处
《防灾减灾工程学报》
CSCD
北大核心
2012年第5期624-628,共5页
Journal of Disaster Prevention and Mitigation Engineering
基金
国家自然科学基金项目(50608038)
霍英东青年教师基金项目(91076)
江苏省"六大人才高峰"项目(06-F-014)资助
关键词
隧道基础
埋深效应
施工找平
沉降变形
foundation of tunnel
effect of buried depth
construction leveling
settlement deformation
