摘要
Abstract
For the drainage pipeline renovation project of Donghai Road in Binhai New Area,Tianjin,in order to the dual challenges of construction obstacles caused by silty soil(high compressibility,low bearing capacity)and the protection requirements for surrounding sensitive structures such as the foundations of coastal expressway viaducts,the application effect of the slurry balance pipe jacking technology in such complex conditions was systematically studied based on engineering practice.Multiple-dimensional technical optimization was implemented:In terms of construction parameters,the jacking speed was controlled within 10～30 mm/min,the thixotropic mud was precisely mixed at a ratio of 1∶4∶0.05,and the maximum jacking force of the DN3 200 rectangular pipe was strictly controlled within 14 837 kN;In terms of construction technology,three rows of high-pressure jet grouting piles were used for reinforcement at the entrance and exit of the tunnel and the slurry discharge system was optimized to make the effective control of the ground surface settlement.The settlement monitoring results showed that the optimized slurry balance pipe jacking technology can effectively balance the excavation face pressure.The ground surface settlement showed a three-stage evolution characteristic of"gradual settlement-rapid drop-stable convergence".The final maximum settlement was only 12.76 mm,fully meeting the requirements of the specifications and the protection of sensitive structures.This study verified the reliability of the slurry balance pipe jacking technology in complex geological and sensitive environments,providing parameter and process references for similar underground pipeline projects.关键词
排水管网改造/泥水平衡顶进技术/非开挖施工/沉降控制/顶管参数优化Key words
drainage pipeline renovation/slurry balance pipe jacking technology/trenchless technology/settlement control/optimization of pipe jacking parameters分类
建筑与水利
