北京××工程基坑护坡工程施工方案.doc

基坑护坡工程施工方案

1．概述
北京X工程，位于北京市XX区，东临XX路，南临XX。本工程A、B、E座地上XX层，C1～C2、D座地上X层，全现浇剪力墙结构。4层框架结构综合楼，均设2层地下室。自然地面标高为36.30m，±0.000绝对高程为37.50m，基础埋深约6. 00m。
因施工现场狭窄，为保证周边建（构）筑物的安全和基础施工的顺利进行，须对基坑进行有效支护。
本场地工程地质性质详见《工程地质勘察报告》。
2．基坑护坡设计及施工方案
2.1   设计依据
2.1   北京市XX勘察院提供的本场地《工程地质勘察报告》。
2.2   体重度统一取为 r = 20kN/m 。
2.3   地面超载按一般情况，考虑为 q=20kN/ m 。
2.4   设计与计算遵循国家及北京市有关规范，主要有：
《建筑地基基础设计规范》(GB50007-2002）
《混凝土结构设计规范》(GB50010-2002 )
《建筑基坑支护技术规程》(JGJ120-99 )
《建筑地基处理技术规范》(JGJ79—2002）
2.2   设计方案
根据我公司在北京地区施工经验，结合类似工程实际情况，综合考虑技术安全和经济合理，采用锚喷土钉墙方案。东侧、南侧作斜坡，共4排土钉，从上至下长度依次为5m、6m、5m、4m，锚筋1φ16，四排锚筋φ，间距依次为1.4m、1.3m、1.3m、1.4m，水平间距1.4m；西侧、北侧、东南角按1:0.5放坡，共4排土钉，从上至下长度依次为5m、5m、5m、4m，锚筋1φ16，间距依次为1.4m、3m、3m、l.4m，水平间距1.4m.。
以上设计土钉倾角均为5°～100°横压筋2φ14通长，竖压筋2φ14通长，与横压筋在土钉墙端部井字架形焊接。土钉成孔直径100mm钢筋网片φ6＠200×200，现场绑扎或焊接而成；面层喷射C20混凝土，厚度60～80mm。
本工程采取信息法施工，各段土钉的排数、长度、间距应根据实际情况由现场技术负责人做出调整。
A座西侧化粪池采用护坡桩，桩数14根，桩长12m，桩径600mm,混凝土
Pit Slope Construction Scheme

1. Outline
Beijing X project, located in Beijing XX District, east XX Road, south XX. The project A, B, E Block XX ground floor, C1 ~ C2, D Block, X ground floor, the whole place shear wall. Comprehensive Building 4 story frame structure, located 2 basement. Natural ground elevation of 36.30m, ± 0.000 absolute height is 37.50m, based on depth of about 6. 00m.
Narrow due to the construction site, in order to ensure the surrounding building (structures) based on the safety and smooth progress of construction shall be effective on the foundation support.
The geological nature of the site see "Engineering geological investigation report."
2. Pit slope design and construction scheme
2.1 Design Basis
2.1 XX Investigation Institute in Beijing provided the venue, "Engineering geological investigation report."
2.2 The degree of unity of body weight taken as r = 20kN / m.
2.3 Overloading the ground by the general situation, consider q = 20kN / m.
2.4 The design and calculation to follow the relevant norms of national and Beijing, including:
"Building Foundation Design Code" (GB50007-2002)
"Design of concrete structures" (GB50010-2002)
"Technical Specification for Construction Excavation" (JGJ120-99)
"Treatment of Building technical specifications" (JGJ79-2002)
2.2 design
According to our construction experience in the Beijing area, combined with the actual situation similar projects, technical security and comprehensive consideration of economic rationality, use of shotcrete soil nail wall program. East, south to the slopes, a total of 4 rows of soil nails, from top to bottom length of the order of 5m, 6m, 5m, 4m, Anchorage 1φ16, four rows Anchorage φ, pitch were 1.4m, 1.3m, 1.3m , 1.4m, level spacing 1.4m; west, north, southeast corner by 1:0.5 sloping, a total of 4 rows of soil nails, from top to bottom length of the order of 5m, 5m, 5m, 4m, Anchorage 1φ16, spacing were 1.4m, 3m, 3m, l.4m, level spacing 1.4m..
Angle over the design of soil nails are 5 ° ~ 100 ° horizontal pressure bar 2φ14 through long, vertical bar 2φ14 pressure on inflation, and the horizontal pressure bar in the soil nail wall frame with welded end crosswise. Nail hole diameter of 100mm steel mesh φ6 @ 200 × 200, field banding or welding; C20 concrete surface jet, thickness 60 ~ 80mm.
Construction of this project to Information Act, the section of rows of soil nails, length, spacing should be based on the actual situation on the spot and technical managers to make adjustments.
The west side of Block A septic tank use of piling, pile number 14, the pile length 12m, pile diameter 600mm, concrete