摘要
为解决公路隧道复合衬砌结构性裂缝病害导致的使用寿命降低和运营安全隐患,以宜兴阳灵隧道典型地质段为研究对象,提出了围岩地质环境、施工工艺和混凝土材料对二次衬砌产生结构性裂缝的影响机制:(1)拆模过早是致使二次衬砌混凝土早期强度不足,在自重应力和围岩挤压应力作用下导致在其内部产生隐性裂纹;(2)混凝土欠养护导诱发的温度梯度应力诱发裂纹尖端应力集中致使其内部隐性裂纹扩展和贯通。针对不同开度的裂缝提出了相应的灌浆加固处治措施以提高衬砌结构强度和整体性,有效保障了隧道运营期围岩和维护结构安全。
To solve the service life reduction and operation safety risks induced by structural cracks in the composite lining of a highway tunnel,this paper presents the typical geological section of Yangling Tunnel in Yixing as a case history and evaluates the influence mechanism of the geological conditions of surrounding rock mass,construction methods and the concrete material on the structural cracks in the secondary lining.The results indicate that,(1) the premature form work removal resulted in insufficient early strength of the secondary lining of the concrete,which led to hidden cracks in its interior under the action of dead weight stress and the surrounding rock compressive stress;(2) the stress concentration at the end of the crack induced by the temperature gradient stress induced by the under-curing of concrete led to the growth and the coalescence of the hidden cracks inside.In the view of the cracks with different opening degrees,the corresponding grouting reinforcement treatment measures are proposed to improve the strength and the integrity of the lining structure and effectively ensuring the safety of the surrounding rock mass and the maintenance structure during the operation of the tunnel.
作者
练强
冯恺
LIAN Qiang;FENG Kai(Yixing Transportation Engineering Construction Management Office,Yixing 214200;JSTI Group Co.Ltd.,Nanjing 210019)
出处
《土工基础》
2022年第3期383-386,共4页
Soil Engineering and Foundation
关键词
山岭隧道
结构性裂缝
稳定性分析
处治措施
highway tunnel
structural cracks
stability analysis
mitigation measures
