非岩溶隧道排水系统结晶机理及防治措施研究

Study on Crystallization Mechanism&Prevention Measures of Non-Karst Tunnel Drainage System

以大量文献调研为依据,分析非岩溶隧道排水系统结晶主要因初支混凝土析出Ca^(2+)与地下水中HCO_(3)-等反应生成CaCO_(3),并在较为粗糙的排水管内壁表面慢慢附着、沉淀集聚,引发堵塞病害。地下水中HCO_(3)-浓度高是造成隧道结晶堵塞的重要因素之一。珠海地区因地下水中HCO_(3)-离子含量较高,可能引发隧道排水系统结晶。隧道地下水排水系统隐蔽性强,结晶堵塞病害的监测难度大且可维护性差。针对隧道排水管结晶堵塞,建议加强隧道排水系统监测及可维护性设计,采取降低初期支护混凝土水化产物中钙和碱含量、优化排水管性能、提高排水系统排水能力、加强隧道排水系统监测及可维护性设计等工程措施,尽可能减少结晶体生成和沉积。采用的措施可为类似工程提供参考。

Based on a large number of literature research,it is analyzed that the crystallization of non-karst tunnel drainage system is mainly caused by the reaction between Ca^(2+)precipitated from primary concrete and HCO_(3)-in groundwater to generate CaCO_(3),which slowly adheres to&accumulates on the inner wall surface of relatively rough drainage pipes,causing plugging disease.The high concentration of HCO_(3)-in groundwater may be one of the important factors that cause the tunnel crystallization blockage.Due to the high HCO_(3)-ion content in groundwater in Zhuhai area,the crystallization of tunnel drainage system may occur.The underground water drainage system of the tunnel has strong concealment,and the monitoring of crystal blockage disease is difficult&poor maintainability.In view of crystal blockage of tunnel drainage pipe,it is recommended to strengthen monitoring&maintainability design of tunnel drainage system,take engineering measures such as reducing calcium&alkali content in hydration products of initial support concrete,optimizing drainage pipe performance,improving drainage capacity of drainage system,strengthening monitoring&maintainability design of tunnel drainage system,which can reduce crystal formation&deposition as much as possible.These measures can provide reference for similar projects.