四、基坑护坡工程施工方案.doc

拟建北京×工程，位于北京市××区，东临××路，南临××。本工程A、B、E座地上××层，C1、C2、C3座地上×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36.30米，±0.00标高为37.50米，基础埋深约6.00米。    ’
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、基坑护坡设计方案
2.1  设计依据
    1、北京市××勘察院提供的本场区《工程地质勘察报告》
    2、体重度统一取为r=20kN／m3。
    3、地面超载按一般情况，考虑为q：20kN／m3。
    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》(Jql20—99)
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5米、6米、5米、4米，锚筋1Ф16，四排锚筋1Ф18，间距依次为1.4米、1.3米、1.3米、1.4米，水平间距1.4米；西侧、北侧、东南角按1:0.5放坡，共4排土钉，从
Beijing × proposed project, located in Beijing × × area × × Road east, south × ×. The project A, B, E Block, ground × × layer, C1, C2, C3, Block × ground floor, the whole place shear wall. Comprehensive Building 4 story frame structure, located 2 basement. Natural ground elevation is 36.30 m, ± 0.00 to 37.50 m elevation, based on depth of about 6.00 meters. '
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
2.1 Design Basis
    1, Beijing × × Investigation Institute of the site area to provide "engineering geological investigation report"
    2, weight degree of unity is taken as r = 20kN/m3.
    3, overloading the ground by the general situation, consider q: 20kN/m3.
    4, 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" (Jql20-99)
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 5 meters, 6 meters, 5 meters, 4 meters, Anchorage 1Ф16, four rows Anchorage 1Ф18, spacing were 1.4 m, 1.3 m, 1.3 m, 1.4 m, 1.4 m horizontal distance; west, north, southeast corner by 1:0.5 sloping, a total of 4 rows of soil nails, from the