CAJ | 학술논문

时域反射仪(TDR)是一种利用电磁脉冲方法，根据电磁波在土层中的传播速度测试不同土层的介电常数，按介电常数值可获不同土类在冻融状态下的未冻水含量和总体积含水量．TDR仪可在野外环境下无破损地测得融土和冻土的液态水含量，尤其是能测出不同负温下冻土中未冻水的变化．该仪器最适用于测量均质细颗粒土的体积含水量．经与烘干称重法对比，TDR仪应用在青藏高原上不同融土类所测含水量值的误差范围：粉土和细砂为±2.5％,粘土和亚粘土为±3.0％，砂砾石土和碎石土为±5％．经过反复的野外实践证明,用TDR仪测上层含水量具有简便、快速及稳定等优点，是值得推广的方法．根据青藏公路沿线8个场地埋置的TDR仪和地温仪所获的一个年周期的水．热资料(1997.8-1998.7)．分析了高原活动层在冻融过程中温度场和水分场的耦合所导致的水分迁移及水分场重分布的规律．
시역반사의(TDR)시일충이용전자맥충방법，근거전자파재토층중적전파속도측시불동토층 적개전상수，안개전상수치가획불동토류재동융상태하적미동수함량화총체적함수량．TDR의가재 야외배경하무파손지측득융토화동토적액태수함량，우기시능측출불동부온하동토중미동수적변 화．해의기최괄용우측량균질세과립토적체적함수량．경여홍간칭중법대비，TDR의응용재청장고 원상불동융토류소측함수량치적오차범위：분토화세사위±2.5％,점토화아점토위±3.0％，사력석 토화쇄석토위±5％．경과반복적야외실천증명,용TDR의측상층함수량구유간편、쾌속급은정등 우점，시치득추엄적방법．근거청장공로연선8개장지매치적TDR의화지온의소획적일개년주기적 수．열자료(1997.8-1998.7)．분석료고원활동층재동융과정중온도장화수분장적우합소도치적수분 천이급수분장중분포적규률．
Using electromagnetic pulses, Time-Do- main-Reflectometer (TDR) soil moisture is deter- mined by measuring dielectric constant for different soil layers. TDR can be used to determine the liquid water content of soils in unbroken state in field, specially the unfrozen water content of frozen soils in different temperatures. It is more suitable to measure bulk moisture content of finegrained soils. Compared with gravitational method, the accuracy of TDR in de- termination of bulk moisture content on the Tibetan Plateau is: ± 2.5% for silt and fine grained sand, ±3.0% for clay and sandy clay and　±5% for gravel and pebble soils. It can be concluded by repeated field practices that there are many advantages of TDR in determination of soil moisture contents in field, I.e., simple, convenient and quick for field measuring and stable in the measuring results. Based on the moistrue and temperature data (August 1997 to August 1998) from 8 sites along the Tibetan Highway, the moisture migration in the active layer due to freezing is ana- lyzed in this paper.