基坑-挡土-土钉-桩.doc

摘 要 本设计为办公大楼的基坑支护设计。本设计是根据国家现行建筑基坑支护技术规程,在给定地质勘察报告的条件下，进行基坑支护设计，主要目的是掌握基坑支护的设计方法。本设计采用了钻孔灌注桩、混凝土挡土墙、土钉墙、重力式挡土墙等基坑支护结构。在土压力计算过程中，运用了朗肯土压力理论；在内力计算过程中，运用了等值梁法；在配筋计算过程中，参照了混泥土结构设计规范;在钢支撑设计时，参照钢结构设计规范；在降水处理设计时参照了建筑基坑支护技术规程；计算过程中除了以国家现行建筑基坑工程技术规程为依据外,还大量的把实际经验运用其中,加强理论与实践的结合。此次设计的主要指导原则是如何保证基坑的安全可靠、方便施工，并达到经济的效果。通过这篇论文，直观的说明了基坑支护设计所需的各种参数。工程技术人员在进行基坑支护设计时可参照本文的设计方法。 [关键词]基坑支护；钻孔灌注桩；重力式挡土墙；土钉墙；降水处理 Abstract This design is the foundation pit design of a district. This design accords to the current nation technical specification for retaining and protection of building foundation excavations,and the report of geology investigate ,which are given at first.The main purpose of the design is to grasp the design methods of foundation pit support.The design has used the foundation pit support methods of bored caisson pile、soil-nailed wall、concrete gravity breast wall and so on.During the calculating of soil pressure,put the soil pressure theories of W.J.M.Rankine to use ; In the course of calculating in internal force , make use of the equivalent beam method; when matching the steel to calculate,have comply with the cement structure design specification norm; In the design of draining,make use of the technical specification for retaining. And strengthened the combination of the actual experience with the theories.The guideline of this design is how to guarantee the foundation pit safe 、 reliable、convenient to construct, and reach the economic result. Through this thesis, we can see various kinds of parameters that are needed in the foundation pit support design. Engineers and technicians can consult the design method of this text while carrying on the foundation pit support design. [Keywords] foundation pit support; bored caisson pile; gravity breast wall; draining 目 录 摘 要 1 1前 言 １ 2 设计方案综合说明 ２ 2.1工程概况 ２ 2.2方案概述 ３ 3内力计算 ４ 3.1划分计算区段 ４ 3.2确定支护设计参数 ４ 3.3计算土压力 ４ 3.4支撑力Ｔ的计算 ８ 3.5嵌固深度的计算 ９ 3.6桩内最大弯矩计算 １０ 3.7桩体配筋的计算 １１ 4围檩设计计算 １３ 4.1第一道围檩即冠梁 １３ 4.2第二道围檩设计计算 １４ 5 内支撑结构设计计算 １５