郑(州)西(安)客运专线高桥隧道变形原因浅析

研究目的:多座大断面黄土隧道在施工过程中均出现了不同程度的地表裂缝,尤其在隧道浅埋偏压段更为突出,因此对大断面黄土隧道进行深入调查及针对大断面黄土隧道的施工方法,支护结构和围岩的应力、变形情况、地表裂缝情况开展研究是很有必要的。研究结果:确定隧道产生变形的原因是由于黄土结构相对疏松、施工开挖面大、施工工艺控制不严格且隧道变形地段存在偏压等原因造成的,从而提出大断面黄土隧道在浅埋段宜采用短进尺,强支护,快封闭,勤量测,二衬紧跟的施工原则,并做好地表及拱顶下沉检测工作。

Analysis of Cause for Deformation of Gaoqiao Tunnel of Zhengzhou-Xi'an Railway Passenger Dedicated Line

Research purposes:The surface cracks of varying degrees appear on some large sectional loess tunnel during construction,especially in the shallow buffed and offset pressured section of tunnel,so it is necessary to do deep researches on the large sectional loess tunnel,including construction method,support structure, situations of stress and deformation of wall rock and situation of surface crack. Research results:The causes for deformation of tunnel are the loess structure is relative loose,the excavated section is large during construction,the control of construction technique is not conducted well and the offset pressure exists in the deformation section of tunnel.Therefore,the principle of construction of large sectional loess tunnel is proposes,namely short footage,strong support,quick closure,frequent measuring and secondary lining soon for the shallow buried section of tunnel.Also the work of checking the subsidence of surface and arch top should be well done.