郑州市下穿中州大道隧道工程采用矩形顶管法进行施工，顶管段具有断面超大、覆土浅、间距小、推进距离长、未采用中继间等特点，顶管推进推力大。为有效控制顶管推力，研究了注浆孔布置、触变泥浆配制、注浆管路优化设计和管节表面涂蜡等顶管减阻技术。结果表明，本工程采用的减阻技术效果良好。

The tunnel crossing underneath Zhongzhou Road in Zhengzhou is constructed by rectangular pipejacking. The thrusting force of the pipejacking is large due to its extralarge crosssection, shallow overburden, small spacing, long advancing distance and without using relaying chamber. In order to control the thrusting force effectively,the layout of grouting holes, preparation of thixotropic slurry, optimized design of grouting pipe and waxing of pipe surface are studied in detail. The results show that the drag reduction technologies used can achieve good effect.