基土钎探工程方案.doc

 一、 施工准备
（一） 材料要求
砂：一般为中砂。
（二） 主要机具
1、 工打钎：一般钢钎，用直径φ22～25mm的钢筋制成，钎头是60°尖锥形状，钎长1.8～2.1m；穿心锤(重10kg)。
2、 机械打钎：轻便触探器。
3、 其他：麻绳或铅丝、梯子(凳子)、手推车、撬棍(拔钢钎用)和钢卷尺等。
（三） 作业条件
1、 基土已挖至基坑(槽)底设计标高，表面应平整，轴线及坑(槽)长、宽均符合设计图纸要求。
根据设计图纸绘制钎探点平面布置图，确定钎探点位置及顺序编号，按照钎探图及有关规定进行钎探并记录。钎探点的布置依据设计要求，当设计无要求时，应按规范规定执行，也可参照表l-l执行。
  Pit Slope Construction Scheme

    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. 4 story frame structure of complex building, located 2 basement. Natural surface elevation of 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, considering the technical security and 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