岩溶隧道衬砌施工缝排水设施可维护性试验研究

岩溶隧道普遍存在排水系统出现结晶的问题,造成隧道排水不畅、衬砌水压过大、渗漏加剧等问题,对隧道的运营使用和结构安全造成影响。为提高岩溶隧道排水设施的可维护性和减少结晶现象,依托岩溶地区隧道衬砌施工缝渗漏水处治工程实例进行实践和探讨。该隧道的4条施工缝在通车后出现严重的渗漏水问题,通车2年后进行引排处治,但是由于岩溶水的结晶造成排水系统堵塞失效而复漏。在第二次处治中,对原处治方案进行改进:采用防护涂料对混凝土基面和PVC管壁面进行疏水处理,以减少碳酸钙结晶的附着;预留检查孔,可结合工业内窥镜对排水管内的结晶和堵塞情况进行检查。通过处治后约半年周期的检查结果证明,经过改进处治后的衬砌施工缝中结晶的情况明显减少,且排水系统的可维护性也得到提高。

Experimental Research on Maintainability of Drainage Facilities in Lining Construction Joints of Karst Tunnel

Crystallization in drainage system is a common problem in Karst tunnels, which results in poor drainage performance, excessive lining water pressure and intensified leakage, and has an impact on the operation and structural safety of tunnels. In order to improve the maintainability of drainage facilities of karst tunnels and reduce the crystallization phenomenon, practices and discussions are carried out based on the treatment of leakage water in lining construction joints of a Karst tunnel. Four construction joints of the tunnel lining have serious leakage problems, hence the drainage treatment is conducted 2 years later after the tunnel is opened to traffic. However, due to the crystallization of karst water, the drainage system is blocked and failed and leakage occurs again. During the second treatment, the original treatment is improved: the concrete subbase and the wall of PVC pipe are hydrophobically treated with protective coating to reduce the adhesion of calcium carbonate crystals; inspection holes are reserved to check the crystallization and blockage of the drainage pipe with industrial endoscope. The results of inspections about half a year after treatment show that the crystallization in the lining construction joints is obviously reduced and the maintainability of the drainage system is also improved.