CAJ | 학술논문

为有效应用基于分布式光纤测温的渗流热监测技术，需研究待监测区的背景温度场特征。为此，建立了土石坝饱和-非饱和瞬态渗流场与温度场耦合模型（流-热耦合），模型考虑了热对流、热传导和热扩散效应，温度边界按周期性气温考虑，且相关参数按非线性考虑，如流体黏度的热效应、导热系数受含水率影响等，其仿真结果更接近土石坝温度场的真实状态。基于典型算例，讨论了与大气温度相关的周期性波动温度场特征。计算结果表明：温度场受坝体渗流和气温的影响，库水及气温是两个重要热源，饱和带的温度受库水渗流控制，非饱和带主要受气温控制，具有季节波动特征；在土石坝心墙部位若发生集中渗漏，渗漏通道附近岩土体的温度受库水影响；若在心墙上敷设分布式光纤传感器，很容易捕捉到渗漏点位置及渗漏发生的时刻。渗流热监测技术在理论上可以反映渗流场的时空分布特征，在资料分析中还应关注由气温波动引起的温度异常。
위유효응용기우분포식광섬측온적삼류열감측기술，수연구대감측구적배경온도장특정。위차，건립료토석패포화-비포화순태삼류장여온도장우합모형（류-열우합），모형고필료열대류、열전도화열확산효응，온도변계안주기성기온고필，차상관삼수안비선성고필，여류체점도적열효응、도열계수수함수솔영향등，기방진결과경접근토석패온도장적진실상태。기우전형산례，토론료여대기온도상관적주기성파동온도장특정。계산결과표명：온도장수패체삼류화기온적영향，고수급기온시량개중요열원，포화대적온도수고수삼류공제，비포화대주요수기온공제，구유계절파동특정；재토석패심장부위약발생집중삼루，삼루통도부근암토체적온도수고수영향；약재심장상부설분포식광섬전감기，흔용역포착도삼루점위치급삼루발생적시각。삼류열감측기술재이론상가이반영삼류장적시공분포특정，재자료분석중환응관주유기온파동인기적온도이상。
In order to implement the seepage monitoring with temperature in embankment dam with the popular distributed fiber optic temperature sensor system (DTS), it’s necessary to study the background characteristics of temperature field. Herein, a saturated-unsaturated seepage field and temperature field coupling model (thermal-hydro coupling, i.e. T-H) is established. The model considers the heat convection-conduction-diffusion, as well as the boundary periodically fluctuation with atmosphere temperature. Some parameters are considered nonlinearly so that the result of simulation is closer to the true state of dam temperature field. For instance, the fluid viscosity is influenced by temperature and thermal conductivity is influenced by moisture, and so on. A clay core embankment dam is taken as a case study. It is shown that the temperature field within the dam has the characteristics of seasonal fluctuation, which is controlled by seepage and atmospheric temperature. Specifically, the heat from the reservoir controls the temperature variation of the saturated zone and the heat from atmosphere controls that of the unsaturated zone. If the core wall leaks, the temperature nearby will reduce as cold reservoir water flowing into. In this case, the distributed fiber sensors lying on the core wall can be used to detect spatial and temporal distributions of leakage. The conclusions are drawn as follows that the seepage monitoring with temperature is effective in theory. In the data analysis, particular attention should be paid to the temperature anomalies caused by atmosphere temperature.