水岩耦合巷道掌子面破裂的红外时空演化特征

Infrared Space-time Evolution of the Fracture Characteristics in Water-rock Coupling Tunnel Face

利用红外热像仪进行无水、无压水、承压水作用下石灰岩双轴加载破裂失稳观测实验,研究巷道掘进时掌子面破裂过程中的红外辐射时空演化规律,以此识别掘进方向的水体情况。实验结果表明:掘进前方不含水体时,掌子面破裂在时序上表现为温度线性升高,破裂前升温加速,在空间上表现为前期均匀升温,临近破裂前出现温度场分异,形成局部高温区,升温加速;掘进前方存在无压水时,温度曲线呈"一级台阶"状上升,热像表现为高温场包围低温场;掘进前方存在承压水时,温度曲线呈"波浪"状上升,热像交替升降温,最终大幅度降温。研究结果可为巷道开挖的遥感观测及巷道渗漏水预测提供理论指导。

The experimental observation of the limestone fracture with biaxial loading and under the action of no water, unconfined water and confined water was carried out by infrared thermal imaging system. Infrared space-time evolution of tunnel face fracture was studied in the process of roadway driving, so as to identify the water state in the direction of driving. The experimental results showed that, when driving under no water, in time sequence, the tunnel fracture performed as linear increase of temperature and accelerated warming before rupture; in space sequence, the increase of temperature was uniform at early stage, then differentiation of temperature fields occurred near the rupture and a local high- temperature region was formed with sharp warming. When driving under unconfined water, the temperature curve rose step by step, and the thermal image expressed as a low temperature field being surrounded by a high temperature field. When driving under confined water, the temperature curve increased like wave, and the thermal image was alternately rising and falling, with a significant cooling ultimately. The research results could provide theoretical guidance for the remote sensing observation and the prediction of tunnel leakage.