杨育红
【摘 要】穿越西张僧河顶套管施工,上部需穿越排污箱涵及PCCP压力管线,排污盖板涵为浆砌石砌筑,底部距顶管顶部距离约3.8m。根据顶管施工安全要求,顶管覆土厚度不小于1.5倍的顶管外径。该处在顶管施工过程中,由于基础扰动存在安全隐患,特需对顶管上部排污箱涵及PCCP管线土体做固结灌浆进行加固处理。为确保土体加固效果,采用斜孔灌浆。
【Abstract】During the construction of casing crossing the top of Xizhangseng River, the upper part needs to pass through the sewage box culvert and PCCP pressure pipeline. The sewage cover culvert is built with mortar masonry, and the distance from the bottom to the top of pipe jacking is about 3.8m. According to the safety requirements of pipe jacking construction, the thickness of pipe jacking soil shall not be less than 1.5 times of the outer diameter of pipe jacking. In the process of pipe jacking construction, due to the potential safety hazard of foundation disturbance, it is necessary to reinforce the soil of the sewage box culvert on the top of pipe jacking and PCCP pipeline by consolidation grouting. In order to ensure the effect of soil reinforcement, inclined hole grouting is used.
【关键词】顶管施工;灌浆;排污箱涵;PCCP
【Keywords】pipe jacking construction; grouting; sewage box culvert; PCCP
【中图分类号】U417 【文献标志码】A 【文章编号】1673-1069(2021)08-0181-02
1 工程概况
黄水东调应急工程调出区为东营市,调入区为胶东地区青岛、烟台、威海、潍坊四市,所调水量均为利用各市现有的引黄指标,不新增引黄指标水量。应急工程的主要供水对象为潍坊市,通过与引黄济青渠道连通兼顾向青岛市等其他三市供水。调水线路涉及东营市垦利县、东营区、广饶县、寿光市、潍坊滨海区共5个市(区、县),应急工程直接受水区为潍坊市及潍坊市北部地区,主要有潍坊市、寿光市、潍坊滨海经济技术开发区等。
穿越西张僧河(桩号:24+660.0~24+800.0,长度140m)为顶套管穿越。套管规格为DRCPⅢ DN3000顶管用钢筋混凝土管,其套管技术要求满足GB/T 11836、设计埋深、相应河道等级、穿越污水线路等荷载要求,套管外防腐喷涂环氧煤沥青,套管内输水管道规格为Φ2444*22mm螺旋钢管,双管输水,双管中心距8.0m,输水管道与套管之间填充中粗砂。
2 施工布置及施工准备
2.1 施工布置
①工作井布设在管线上游桩号24+660处,工作井左右两侧布置吊车平台,套管堆放场地,泥浆池等;接收井布设在管线下游桩号24+800处;就近临时布置钢筋、模板,钢板桩加工场地。……