重粉质砂壤土中长距离大口径顶管施工

Construction of Long-distance Large-diameter Pipe Jacking in Heavy Silty Loam

某引水枢纽工程,采用顶管法施工,总长约3.0km,共分为3段,其中4号井至3号井为1300m超长距离顶管区间段。顶管上部和切削断面均为重粉质砂壤土,采用大刀盘泥水平衡顶管掘进机施工。在顶管顶进至约80m时,开始出现大范围地面沉降,顶管顶力剧增,顶管姿态变化大,设备连续故障等现象。经认真分析原因并制订针对性施工技术措施,最终确保了重粉质砂壤土复杂地质下该超长距离顶管区间段得以贯通。该文对该超长距离顶管区间段顶管施工进行了认真分析和总结。其结论与建议可供今后类似超长距离顶管工程借鉴。

The pipe-jacking method is used to construct a water diversion project.Its total length is about 3.0 km and is divided into three sections,in which 1300-m over-long-distance pipe jacking section is from No.4 Shaft to No.3 Shaft.The upper of pipe jacking and the cutting section are all heavy silty loams,which are constructed by the cutter slurry balance pipe jacking machine.The phenomenon of large-scale ground settlement,jacking force increment,large Pipe jacking attitude change and continuous equipment failure occurs when the pipe jacking is constructed at about 80 m.The article analyzes the causes and works out the special construction technical measures finally to ensure this long-distance pipe-jacking section being through in the complex geology of heavy silty loam.The article analyzes and sums up the pipe-jacking construction of this over-long-distance pipe-jacking section.The conclusion and suggestion can be referred for the similar over-long-distance pipe-jacking project.