摘要
软岩隧道拆换拱施工中发生大塌方,并造成附近二次衬砌严重开裂的报道及相关研究较少,为安全有效地进行软岩隧道塌方处治,以甘肃某高速公路深埋炭质板岩隧道大塌方处治为例,介绍了隧道塌方经过及采取的应急处治措施,分析了隧道塌方原因,制定了初支塌方段和二衬开裂段相应的综合处治方法,并根据现场实施情况以及衬砌结构安全性计算结果,评价了隧道塌方处治效果。结果表明:塌方段炭质板岩呈碎裂状松散结构,由于发生过度变形,加上注浆固结效果不佳,拆换拱时围岩以碎屑状快速溜塌、涌出,直至围岩整体失稳,塌方体填满整个隧道,进而造成了附近二次衬砌严重开裂;针对初支塌方段和二衬开裂段,宜采用先进行初支塌方段处治、后进行二衬开裂段处治的施工顺序;利用隧规公式所得隧道塌方高度偏小,建议选取基于普式理论所得塌方高度及相应荷载用于隧道塌方段衬砌结构安全性的验算。
There are few reports and related studies on the collapse of soft rock tunnel during the removal and arch replacement construction and the serious cracking of the secondary lining nearby. In order to safely and effectively manage tunnel collapse, we take the collapse of a deep carbonaceous slate tunnel in Gansu Province as an example to analyze the causes of the tunnel collapse and formulate the corresponding comprehensive treatment methods for the collapsed section of primary support and the cracked section of secondary lining. The treatment effect of the tunnel collapse was evaluated according to the field implementation and the calculation results of the lining structure safety. The results show that the carbonaceous slate in the collapsed section has a fragmented and loose structure. Due to its excessive deformation and poor grouting consolidation effect, the surrounding rock quickly collapsed and gushed out in the form of fragments when the old primary support was removed and replaced. At a result, the whole surrounding rock become unstable, the collapse body filled the whole tunnel, and it caused serious cracking of the adjacent secondary lining. For the collapsed section of the primary support and the cracked section of the secondary lining, the construction sequence of treating the collapsed section of the primary support first and then treating the cracked section of the secondary lining should be adopted. In view of the small collapse height obtained by the tunnel specification formula, it was suggested that the collapse height and the corresponding load obtained by Platts theory should be used to check the safety of lining structure in collapsed sections.
作者
王智佼
陈丽俊
魏小军
刘伟伟
王传武
陈党辉
WANG Zhijiao;CHEN Lijun;WEI Xiaojun;LIU Weiwei;WANG Chuanwu;CHEN Dangliui(Gansu Changda Highway Co.,Ltd,Lanzhou,Gansu 730050,China;School of Highway,Cluing'an University,Xi'an,Shaanxi 710064,China;Fujian Road&Bridge Construction Group Co.,Ltd.,Fuzhou,Fujian 350000,China)
出处
《水利与建筑工程学报》
2023年第1期40-47,共8页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金项目(51808049)
甘肃省交通运输厅科技项目(2018-09)。
关键词
隧道工程
深埋隧道
炭质板岩
塌方
处治措施
安全性
tunnel engineering
deep tunnel
carbonaceous slate
collapse
treatment measures
safety
