多刀盘土压平衡矩形顶管隧道土体改良试验研究  

Experimental study on soil improvement during construction of EPB rectangular pipe jacking with multi-cutter

作　　者：许有俊[1] 文中坤 闫履顺 白雪光 刘忻梅[1] 

机构地区：[1]内蒙古科技大学建筑与土木工程学院,内蒙古包头014010 [2]包头城建集团股份有限公司,内蒙古包头014010

出　　处：《岩土工程学报》2016年第2期288-296,共9页Chinese Journal of Geotechnical Engineering

基　　金：内蒙古自治区高等学校科学技术研究项目(NJZY14167);内蒙古科技大学"产;学;研"基金项目(PY-201206)

摘　　要：采用土压平衡矩形顶管施工的内蒙古科技大学地下通道处于砂性土地层中,分别采用了加水与加聚丙烯酰胺(PAM)溶液+粉土泥浆的土体改良方法,土体改良效果不理想,机头刀盘闭塞、结饼现象严重,实际顶进速度仅为1.5 mm/min;在此基础上,采用现场监控量测、室内试验等研究手段,对原土体改良方案进行了室内优化,确定出PAM溶液最佳浓度为2 g/L,膨润土泥浆质量浓度为9%较为合理,添加剂的最佳配比为泥浆注入比为12%,PAM溶液注入比为17%;采用优化后的土体改良配比方案,顶进速度提升至2.8 mm/min,地表沉降监测值均未超过控制标准,能够满足矩形顶管施工的要求。The rectangular pipe jacking method is applied in the underground passage project situated in the Inner Mongolia University of Science and Technology under the condition of sandy stratum. The soil improvement effects are unsatisfactory by using the methods of adding water and the two materials of PAM solution and silt mud. The cutter head is seriously blocked, and the actual jacking speed is only 1.5 mm/min. Therefore, such methods as monitoring measurements and laboratory tests are used to optimize the old soil improvement plan. The research results are as follows： Firstly, the best concentration of PAM water solution is 2 g/L, and the better mass concentration of bentonite mud is 9%; Secondly, the best proportion of additive is that the injection ratio of slurry is 12% and that of PAM water solution is 17%; Thirdly, the jacking speed increases to 2.8 mm/min by using the optimized soil improvement plan, and at the same time, the ground settlement value does not exceed the control standard. The proposed soil improvement method can meet the requirements of rectangular pipe jacking construction.

关 键 词：砂性土地层 土压平衡 矩形顶管 PAM 土体改良 

分 类 号：TU43[建筑科学—岩土工程]