川藏铁路折多山段隧道温度场与热害初步预测

高温热害是川藏铁路面临的主要地质灾害之一。折多山一带地处地热资源丰富的康定地热田,隧道热害问题突出。由于高原山区的交通和施工条件恶劣,在部分区域钻探或其他物探手段难以施展。为了更加精确地预测隧道沿线围岩温度场分布特征,弥补在困难地区勘察工作的不足,基于现场调查获取的地质资料,考虑断层、岩性、地温、地下水等因素,结合稳态法地热研究理论,建立折多山区域地热场模拟数值模型,揭示A隧道方案沿线围岩温度场分布特征;并在前人研究的基础上,对隧道沿线热害危险性进行了分区评价,为隧道线路的选址、设计和施工方案的确定提供参考依据。

Preliminary Prediction of Temperature Field and Thermal Damage in Zheduoshan Region Along Sichuan-Tibet Railway

Heat harm is a common geological hazard in Sichuan-Tibet railway,China.Zheduoshan region is located in the Kangding geothermal field with abundant geothermal resources,which may induce severe thermal damages.Due to the poor traffic and construction conditions in plateau mountainous area,drilling and other geophysical surveys cannot be easily applied.To precisely predict the surrounding rock temperature along the tunnel and compensate for the lack of geological exploration in difficult terranes,a numerical model of tunnel A along the railway line is built and calibrated based on geological data.Faults,lithology,geothermal temperature,groundwater,and other factors are considered in the model based on geothermal theory.The temperature distribution in the surrounding rocks of the tunnel is revealed.In addition,we evaluate the thermal damage risks along the planned tunnel,which would be useful for its site selection,design and construction.