Exploratory Research on Drainage Structure of Highway Tunnel Based on Reducing the Risk of Crystallization Blockage

Crystal blockages of tunnel drainage systems severely undermine the lining structure and operation safety. In order to reduce risk crystal systems, distribution highway defects was identified through a field survey, indoor test, literature analysis, an optimization method structures proposed. The research suggested following: (1) Lining water leakage construction joint were most common in system Renhua–Xinfeng Expressway Yingde–Huaiji Guangdong Province, accounting for 60% 32% total defects, respectively. number that occurred larger granite formation, with road seepage inspection chamber crystallization incidents reaching 2.5/km 2.8/km, (2) groundwater mainly alkaline pH value 8~12, Ca2+ (107 mg/L) cation largest ion concentration, HCO3? (165 anion concentration. crystals predominantly square, spindle, rhombic calcite aragonite composed CaCO3, mixed small amount sediment. (3) To ensure safety, threefold measure proposed, namely, setting one-directional pipes between cable trench roadside blind ditch, applying “?” type anti-crystallization water-stop belts at circular joints secondary lining, both increasing slope transverse pipe using pipe. results will play important role guiding design, construction, maintenance China.