顶推与反拔技术在顶管越江工程中的应用

Application of Pushing and Reverse Pulling Technology in Pipe Jacking Project

以软土富水地区下穿河道钢顶管工程为例,针对此顶管工程在穿越河道期间因顶管机与首节管连接处焊缝破损而导致较大范围漏水,且不能及时有效封堵,进而导致不能继续有效顶进的特殊工况,一方面通过对原接收井进行结构加固,并设置顶推系统,采用顶管机反向沿着原设计轴线向原工作井方向顶进口径稍大于原管径的钢管;另一方面在原工作井内利用千斤顶设置反拔系统。当顶管机反向顶推至原顶管机处,并在轴线上形成对中时同步启动原工作井内反拔系统;原顶管机及管道在顶推力与反拔力的共同作用下逐步被顶推、拔出,并实现管道贯通,该技术可供其他类似工程借鉴。

Taking the steel pipe jacking project under river course in soft soil and water rich area as an example,in view of the special working condition that the joint between the pipe jacking machine and the first section of pipe is damaged during the river course,which leads to a large range of water leakage and cannot be effectively blocked in time,which leads to the inability to continue effective jacking.On the one hand,through the structural reinforcement of the original receiving well and the setting of the jacking system,the pipe jacking machine is used to push the steel pipe with a diameter slightly larger than the original diameter into the original working well along the original design axis in reverse direction.On the other hand,the jack is used to set the reverse pulling system in the original working well.When the pipe jacking machine reversely pushes to the original pipe jacking machine and forms alignment on the axis,the reverse pulling system in the original working well is started synchronously.The original pipe jacking machine and pipeline are gradually pushed and pulled out under the combined action of jacking force and reverse pulling force,and the pipeline is connected.This technology can be used for reference by other similar projects.