地下工程降水及基坑支护施工方案.doc

1 工程概况
本工程位于西安市三付湾，华清路与长缨路交口的西北角，基坑深
度11.20m。
基坑边界条件：基坑东边线距华清路约20m；南侧距长缨路lOm；北
侧距2 层民房3～8m；距基坑西北角约1 5～20m 处有一幢8 层住宅楼：
基坑西侧边线距3 层客运站3～4m，本基坑的坡道准备留于基坑西侧。其
平面位置见图1/3。
支护范围内土层情况：本场地地层情况详见《岩土工程勘察报告书》。
各层土的主要物理力学指标详见表l。
支护土层计算参数 表1
指标
指标值
层号
厚度(m) 深度(m) Y(kN/m3) C（kPa） φ(°)
①人工填土 1.5 1.5 17.00 10.00 l5.00
②黄土 2.8 4.3 16.80 25.00 21.00
③黄土 7.5 11.8 18.30 21.00 12.00
④古土 层 3.O 14.8 18.50 35.00 18.00
陕西储备物资管理局职工培训中心基坑大致呈长方形为71.6m×
33.1m，开挖深度约11.2m；基坑支护采用放坡（1∶0.2）＋土钉墙支护。
基坑底总边长约为209m。支护范围内土层主要为黄土类土，地下水位埋
深5.50m，根据勘察报告提供及地区经验，降

1 Project Overview
The project is located in Xi'an three pay Bay, Hua Qing Road and the northwest corner of Long Ying Road intersections, deep pit
Degree of 11.20m.
Excavation boundary conditions: the east line of pit road from the Chinese Qing Dynasty about 20m; south from Chang Ying Lu lOm; North
Side from the 2nd floor houses 3 ~ 8m; from the northwest corner of the pit is about 1 5 ~ 20m Department has an 8-floor residential buildings:
Pit from the west sideline Layer 3 Terminal 3 ~ 4m, the excavation of the ramp are prepared to stay in the west pit. Its
Flat position shown in Figure 1 / 3.
Support within the soil: The detailed geological conditions of the site, "Geotechnical Engineering Investigation Report."
The main layers of soil physical and mechanical indicators shown in Table l.
Support calculation of soil parameters in Table 1
Index
Index value
Layer No.
Thickness (m) Depth (m) Y (kN/m3) C (kPa) φ (°)
① artificial fill 1.5 1.5 17.00 10.00 l5.00
② loess 16.80 25.00 21.00 2.8 4.3
③ loess 7.5 11.8 18.30 21.00 12.00
④ ancient soil layer 3.O 14.8 18.50 35.00 18.00
Shaanxi stockpile Authority staff training centers roughly rectangular pit is 71.6m ×
33.1m, excavation depth of approximately 11.2m; foundation pit with sloping (1:0.2) + soil nailing wall.
The total length of the bottom side of pit to 209m. Support within the soil is mainly loess type soil, underground water table
Depth 5.50m, according to investigation reports and regional experience, drop