English：

In order to solve the engineering problem of water leakage in the tunnel door wall of the startingwell and the receiving well, the stagnation of pebble in the lower part of the mud water silo in front of thecutter head, the mud cake on the cutter head, and the leakage of cement slurry at the shield tail duringshield tunneling crossing the Yellow River under strong permeable sandy pebble strata, relying on theshield tunnel of Zhongning Cogeneration Central Heating Pipe Network construction engineering,combined with the field practice,this paper analyzes the parameters of shield tunneling and the selectionof segment assembly, and studies the construction technology of shield tail seal brush replacement in thehole, cleaning the stuck pebble with pressure inlet warehouse, and changing the knife with pressure inletwarehouse. The engineering practice shows that the temporary sealing at the end of the tunnel door andthe treatment measures for the leakage of the tunnel door wall can ensure the smooth start of the shield,the sealing and pressure maintaining measures can clean up the accumulated pebbles of the cutter head ofthe shield and resume the excavation smoothly, and the grouting reinforcement and the replacement of theshield tail sealing brush can solve the problem of the mud leakage at the shield tail.