摘要
基于自行设计的缩尺模型试验装置与模型隧道,通过开展模型试验,重现不同地层涌水涌砂事故中降水与回灌水抢险过程,通过对侵蚀地层的流场、地应力场、位移场和速度场的分析,研究降水与回灌水抢险作用机制。研究表明:降水与回灌水抢险的作用机理是通过改变渗漏过程中的水头差与渗流速度等参数来降低地层渗流侵蚀的发展速度;降水与回灌水抢险中,平衡渗漏点内外的水头差后,地层能形成稳定土拱,削弱渗流流速后土拱不再失稳发展;粉土地层的渗透系数较砂土地层小,降水与回灌水后地下水压力变化将出现明显滞后,实际抢险中可以合理提高降水与回灌水幅度,加快抢险措施的响应速度。研究结论可以为隧道渗漏险情的现场处理提供理论参考与指导。
Based on the self-designed reduced-scale model test device and model tunnels,the model test which simulated the emergency response process of dewatering and rewatering in different strata were carried out.Through the analysis of the flow field,earth stress field,displacement field,and velocity field of the eroded stratum,the mechanism of dewatering and rewatering in the emergency was studied.Through the study,it was pointed out that:the mechanism of dewatering and rewatering was to decrease the development speed of seepage erosion in the stratum by changing the parameters such as water height difference and seepage velocity in the process of seepage;in the process of dewatering and rewatering,after balancing the water height difference inside and outside the seepage point,the stratum could form a stable soil arch,and the soil arch would no longer be destabilized after weakening the seepage flow velocity;the permeability coefficient of silt layer was smaller than that of sand layer,and the change of groundwater pressure after dewatering and rewatering would have obvious delay phenomenon,thus the magnitude of dewatering and rewatering could be reasonably increased in the actual emergency rescue to speed up the response speed of measures.The conclusion of the study could provide theoretical reference and guidance for the on-site treatment of tunnel leakage.
作者
孙齐昊
舒计城
范森
柳献
SUN Qihao;SHU Jicheng;FAN Sen;LIU Xian(Department of Geotechnical Engineering,College of Civil Engineering,Tongji University,Shanghai 200092,China;China Railway 14th Corporation Mega Shield Construction Engineering Co.,Ltd.,Nanjing 211800,Jiangsu,China)
出处
《隧道与地下工程灾害防治》
2023年第4期33-46,共14页
Hazard Control in Tunnelling and Underground Engineering
基金
国家自然科学基金资助项目(52078376)
关键词
盾构隧道
涌水事故
降水
回灌水
抢险机理
shield tunnel
gushing water
dewatering
rewatering
emergency control mechanism
作者简介
第一作者:孙齐昊(1996—),男,安徽马鞍山人,博士研究生,主要研究方向为隧道及地下结构事故与灾害。E-mail:1732381-sqh@tongji.edu.cn;通信作者:柳献(1977一),男,湖北武汉人,教授,博士生导师,博士,主要研究方向为隧道及地下结构服役行为、相关机制与性态控制。E-mail:xian.liu@tongji.edu.cn
