水泥搅拌桩作业标准..docxVIP

广通至大理线扩能改造站前工程水泥搅拌桩作业标准中铁X局集团广大铁路项目部二〇一五年七月一日目 录1.编制依据···················································12.适用范围···················································13.施工准备···················································23.1地质调查················································23.2技术准备················································33.3材料准备················································33.4机具设备················································33.5作业条件················································43.6试桩·····················································44.施工工艺··················································54.1施工工艺流程图·········································54.2施工步骤················································55.施工质量控制·············································66.质量标准及检测···········································77.施工中注意的质量问题····································98.成品保护·················································119.安全健康与环境管理·····································119.1施工过程危害及控制措施·······························119.2环境因素辨识及控制措施·······························12水泥搅拌桩作业标准1.编制依据改建铁路广通至大理线《路基工程设计专用图》施工图《客货共线铁路路基工程施工技术指南》TZ202-2008《铁路路基施工质量验收标准》TB10414-2003《铁路工程基本作业施工安全技术规程》TB10301-2009《铁路路基工程施工安全技术规程》TB10302-2009《铁路土工试验规程》TB10102-2010《地基处理技术规程》JGJ79-20022.适用范围水泥搅拌桩是用于加固饱和软黏土低地基的一种方法，它利用水泥作为固化剂，通过特制的搅拌机械，在地基深处将软土和固化剂强制搅拌，利用固化剂和软土之间所产生的一系列物理化学反应，使软土硬结成具有整体性、稳定性和一定强度的优质地基。广大铁路站前X标段线路跨越山间盆地进入低中山缓坡区及过渡区，线路比邻龙川江，位于盆地边缘，盆地区地形平缓开阔，地形起伏较小，线路经过区域为水稻田，龙川江常年有水，水量较大。线路段内地表第四系坡残积层厚度较大。沟槽内分布有软土，松软土，粉质粘土，一般厚度3～5米；下伏基岩全强风化层较厚，风化差异较大，地层内水质有弱侵蚀性。软黏土力学指标：土体容重γ=17.2～20KN/m3,凝聚力с=6.22～32.75Kpa，内摩擦角Φ=3.45～11.92°，抗剪强度[δ]=60～150kpa段内水泥土搅拌桩采用正三角形布置，桩径采用0.5m，桩间距1.1～1.3m，桩的加固深度3～7m，桩尖打入下卧层（弱风化层或基岩面）不小于0.5m。搅拌桩桩身水泥采用42.5及普通硅酸盐水泥+粉煤灰，水泥参入量定为被加固湿土重量的15～18%，粉煤灰掺入量定为水泥量的20%，水泥浆水胶比选用0.45～0.55。本作业标准适用于标段内所有水泥搅拌桩施工。单台桩基施工作业根据作业场地距电源变压器或供电主干线距离等条件，一般应在150m长度范围内进行作业。3. 施工准备3.1地质调查地基加固施工前，必须具备完整的施工区域地表地下的地质勘察资料及施工区域附近管线、建筑物、构筑物和其他公共设施的构造情况，必要时应作施工勘察和调查以确保工程质量及临近建筑的安全。水泥搅拌桩是利用水泥等胶凝材料与地下土层内软黏土共同作用起到支撑上