【作者】 郭玮；

【导师】 谢康和； 胡安峰；

【作者基本信息】 浙江大学 ， 岩土工程， 2006， 硕士

【摘要】 随着城市建设的不断发展以及高层建筑的兴起和地下空间的开发利用,基坑开挖工程日益增多。土钉支护结构是国外最先发展起来的一种用于土体开挖和边坡稳定的的新型挡土结构,在我国自八十年代引进以来已得到广泛的应用,不仅在北方等土层性质较好的地区,而且在沿海等软土地区也得到了越来越多的应用,但由于其工作原理尚有许多不甚明了之处,故存在理论研究滞后于工程应用现象。 论文首先介绍了土钉支护技术的发展历程,对土钉支护的定义、分类、适用范围、存在的问题做了详细的阐述,对土钉支护结构的工作原理进行了系统分析。在对土钉支护结构水平位移和拉力的分布规律、破坏模式、稳定性进行分析的基础上,对该支护形式的优缺点和适用性进行了总结。同时对土钉支护在施工与监测过程的一些技术问题进行了探讨。 其次,较详细地介绍了土钉支护结构设计的原则、方法和具体的设计计算内容,并对计算原理作了细致的分析讨论;又针对现行的规范设计方法及有限元分析法,阐述了设计计算中应该注意的问题。 最后结合土钉支护具体实例,用现行规范设计方法和有限元分析方法相结合对其进行设计计算,计算分析了分步施工中土钉支护结构中的土体变形、基坑边壁的地表沉降、土钉内力的变化情况,对土钉支护结构的支护机理和工作性能作了更进一步的说明。 本文工作可为土钉支护结构的设计和工程应用提供参考。更多还原

【Abstract】 With the continuous development of the urban construction, the springing up of high-rise buildings and the exploitation of the underground space, the deep excavation project is increasing rapidly. As a new retaining technique developed abroad and used in excavation and slope stabilization, soil nailing has become popular in the excavation project since it was introduced to China in 1980’s, not only in the northern hard-soil area but also in the coastal soft soil zone. However, the actual working mechanism of the soil nailing is still unknown, and the theory about soil nailing does not match its application in the engineering.In this thesis, the developing history of soil nailing and its definition, classification, applicability and the open questions are presented. The working mechanism of soil nailing retaining system is also investigated systematically. Based on the analyses of the distribution rule of the horizontal displacement and the stretching force, the failure pattern and the stability analysis methods, the merits and shortcomings as well as the applicability of such kind of retaining structure are summarized. In addition, some technical problems in the construction and monitoring process are discussed.Secondly, the principle, method and specific content of the soil nailing design are introduced in detail. The calculation fundamentals of soil nailing is also analyzed and discussed. Moreover, some remarks on design and calculation are made for the current standard method and finite element method (FEM) related to soil nailing.Finally, a engineering example is given by using both the current standard method and the FEM. The soil deforming in the retaining structure, the ground surface settlement near the foundation ditch and the variation of the internal force of soil nail during the steps of excavation are calculated and analyzed. The retaining mechanism and working performance of soil nailing are further illustrated.The work presented herein can be used as the reference in the soil nailing design and the engineering applications.更多还原