隧道防冻隔温层厚度的计算

提出利用斯蒂芬公式计算围岩最大冻结深度，利用等效厚度换算法计算防冻隔温层厚度。以西北地区某隧道工程为例，分别采用现场实测与斯蒂芬公式计算得到的围岩最大冻结深度和防冻隔温层厚度，计算结果与实测结果的绝对误差为133 %，表明:在没有实测最大冻结深度的情况下，可通过斯蒂芬公式计算围岩最大冻结深度和防冻隔温层厚度。

Calculation on Thickness of Anti-freezing Thermal-protective Layer for Tunnel

The paper suggests to calculate maximum frozen depth of surrounding rock by Stefan＇s formula and thickness of anti-freezing thermal-protective layer by equivalent thickness conversion method. Taking the tunnel project in the northwest region of china as the example, the maximum frozen depth of surrounding rock and the thickness of anti-freezing thermal-protective layer are obtained by field measurement and Stefan＇s formula respectively with the absolute error between the result calculated and that measured being 1.33 %. It shows that in case of no value measured, maximum frozen depth of surrounding rock and thickness of anti- freezing thermal-protective layer could be calculated by Stefan＇s formula.