为明确公路隧道排水路径中结晶物与水环境变化特征，分析结晶趋势路径变化及趋势计算方法的适用性，以白云岩隧道排水结晶病害为背景，以排水路径“围岩水—初期支护水—排水管水”为分析脉络，对比分析排水路径中结晶矿物含量、8大离子质量浓度及水质参数的变化特征，利用Davis-Stiff饱和指数法和方解石饱和指数法，计算并阐明排水路径中结晶趋势的变化规律，并对上述方法的适用性与主要水环境参数对结晶趋势的影响进行分析。研究结果表明： 1）白云岩隧道排水结晶矿物为方解石，排水路径中方解石含量（质量分数）急剧增长，在围岩内仅占0.6%，在初期支护喷射混凝内占比增至15%，在排水管结晶物中剧增至100%。2）排水路径中初期支护喷射混凝土对水离子质量浓度影响最为显著，围岩水经过喷射混凝土后，Ca2+质量浓度大幅增高，pH值显著增大，HCO-3质量浓度大幅降低，CO2-3质量浓度显著增大，盐度SAL、溶解性总固体TDS和电导率Cond始终呈线性增长趋势。3）排水路径中结晶趋势呈先增大后稳定的变化规律，Ca2+和CO2-3质量浓度对结晶趋势的影响大于温度t与pH值。4）方解石饱和指数法计算的结晶趋势结果与实际情况一致，其适用于白云岩隧道水环境结晶趋势分析。
To investigate the characteristics of crystalline
material and the effect of water environment on the drainage path of highway
tunnels and analyze the applicability of crystallization change and trend calculation
method, a case study is conducted on drainage crystallization disease of
tunnels in dolomites. The drainage path of "surrounding rock waterinitial
branch waterdrainage pipe water" is regarded as
the analysis context to comparatively analyze the variation characteristics of
crystalline mineral content, concentrations of the Eight Ions of water, and
water environment parameters in the drainage path. In addition, the variation
law of crystallization trend in the drainage path is calculated and clarified
using the DavisStiff saturation index method and
calcite saturation index method. Moreover, the applicability of the recommended
methods and the influence of main water environment parameters on the
crystallization trend are analyzed. The results reveal the following: (1) The
tunnels exhibit calcite drainage crystallization, and the content of calcite in
the drainage path increases sharply. The calcites account for 0.6% and 15% of
the surrounding rock 〖HJ2.4mm〗and
primary support shotcrete, respectively. (2) The primary support shotcrete
significantly affect the water environment parameters in the drainage path. It
dramatically increases the concentrations of Ca2+ ions, CO2－3
ions, and pH value and sharply decreases the concentration of HCO－3 ions. Salinity, total dissolved solids, and conductivity exhibit
an increasing trend. (3) The drainage path initially exhibits an increasing
crystallization trend and then stabilizes. The influence of Ca2+ ion and CO2－3 ion concentrations on the saturation trend is greater than that of
the temperature 〖WT《TNR#I》〗t〖WT《TNR》〗 and pH value. (4) The calculation results of the crystallization
trend of the calcite saturation index method are consistent with the actual
situation. Thus, the findings show that the proposed method is suitable for
analyzing the crystallization trend of the tunnel water environment in
dolomite.
