CAJ | 학술논문

在农田水利建设蓬勃发展的同时，灌溉入渗在黄土塬边诱发了严重的滑坡灾害。作为黄土滑坡的典型区域，甘肃黑方台地区近年来受到了密切关注。为了研究入渗条件下黄土边坡的变形破坏机制，在黑方台典型滑坡后壁削取原状土样，开展了3组不同应力路径的三轴试验以模拟边坡的失稳过程。通过开展偏压固结不排水（ACU）试验和饱和恒载（SDL）增孔压试验研究了饱和黄土启动和变形破坏过程；通过开展非饱和恒载（UDL）增湿试验，研究了非饱和黄土启动和变形破坏过程。在此基础上，从应力路径和黄土的微观结构角度阐述了入渗诱发黄土滑坡的力学机制。此外，利用试验结果分析了黄土的典型物理力学特性，结果表明：在埋深应力范围内，该黄土的饱和临界状态线可简化为单一的直线；该黄土的状态边界线可近似为其临界状态线；由UDL试验预测的土-水特征曲线受应力状态影响，较高的应力水平对应较低含水率。
재농전수리건설봉발발전적동시，관개입삼재황토원변유발료엄중적활파재해。작위황토활파적전형구역，감숙흑방태지구근년래수도료밀절관주。위료연구입삼조건하황토변파적변형파배궤제，재흑방태전형활파후벽삭취원상토양，개전료3조불동응력로경적삼축시험이모의변파적실은과정。통과개전편압고결불배수（ACU）시험화포화항재（SDL）증공압시험연구료포화황토계동화변형파배과정；통과개전비포화항재（UDL）증습시험，연구료비포화황토계동화변형파배과정。재차기출상，종응력로경화황토적미관결구각도천술료입삼유발황토활파적역학궤제。차외，이용시험결과분석료황토적전형물리역학특성，결과표명：재매심응력범위내，해황토적포화림계상태선가간화위단일적직선；해황토적상태변계선가근사위기림계상태선；유UDL시험예측적토-수특정곡선수응력상태영향，교고적응력수평대응교저함수솔。
With the great development of agricultural hydraulic engineering in China, irrigation induces serious landslide disasters at the edge of loess plateaus. As a typical region of loess landslides induced by agricultural irrigation, the Heifangtai plateau in Gansu province has been paid closed attentions in recent years. To investigate the deforming and failure mechanism of loess slope due to infiltration, undisturbed specimens are obtained from the backwall of a typical landslide in Heifangtai and are used to conduct three series of stress-path triaxial tests to simulate the process of slope failures. Through conducting anisotropically consolidated undrained (ACU) tests and saturated dead-load (SDL) tests with increased pore-water pressure, the initiation and failure processes of saturated loess are investigated. Through conducting unsaturated dead-load wetting (UDL) tests, the initiation and failure processes of unsaturated loess are investigated. Based on above results, the mechanism of infiltration-induced loess landslide is elaborated from the aspects of stress paths and microscopic structure of loess. Besides, the typical physico-mechanical properties of loess are analyzed. The results show that the saturated loess has a unique critical state line which reflects the major stress level corresponding to the thickness of the loess;the state boundary line of the loess can be approximated by its critical state line;the soil-water characteristic curves (SWCCs) obtained from the UDL tests are affected by the stress state, showing lower water content at higher stress level.