CAJ | 학술논문

为研究红黏土土体非饱和特性，分别针对典型的原状和重塑红黏土，结合Geo-experts自平衡型压力板仪和ZJ型应变控制式直剪仪开展了不同干密度下土样的非饱和土水特征试验和直剪试验，探讨了红黏土的一些典型非饱和物理力学特征。研究结果表明：矿物赋存状态的改变和微结构的变化是导致红黏土重塑前后物理力学性质发生显著改变的重要因素；原状非饱和红黏土土水曲线呈现典型的三阶段型变化特征，具有较为明显的进气值和残余含水量，而重塑的非饱和红黏土则呈现半抛物线型变化特征；对于原状红黏土来说，非饱和土体黏聚力最大值出现在低含水率状态，对应的含水率比土水曲线的残余含水率高5％～10％。因此，在开展非饱和红黏土抗剪强度试验时，在相应含水率区间处适当增加试验组数可优化试验成果，对于重塑红黏土来说，可根据塑限含水率判断重塑红黏土内摩擦角开始显著减小的区间。
위연구홍점토토체비포화특성，분별침대전형적원상화중소홍점토，결합Geo-experts자평형형압력판의화ZJ형응변공제식직전의개전료불동간밀도하토양적비포화토수특정시험화직전시험，탐토료홍점토적일사전형비포화물리역학특정。연구결과표명：광물부존상태적개변화미결구적변화시도치홍점토중소전후물리역학성질발생현저개변적중요인소；원상비포화홍점토토수곡선정현전형적삼계단형변화특정，구유교위명현적진기치화잔여함수량，이중소적비포화홍점토칙정현반포물선형변화특정；대우원상홍점토래설，비포화토체점취력최대치출현재저함수솔상태，대응적함수솔비토수곡선적잔여함수솔고5％～10％。인차，재개전비포화홍점토항전강도시험시，재상응함수솔구간처괄당증가시험조수가우화시험성과，대우중소홍점토래설，가근거소한함수솔판단중소홍점토내마찰각개시현저감소적구간。
In order to study the unsaturated characteristics of red clay,Geo-experts self-balanced pressure plate meter and ZJ direct shear apparatus were used in experiments to investigate the soil-water and shear strength characteristics of the typical undisturbed and remolded red clays under different dry densities. Based on the experimental results,the physical and mechanical features of unsaturated red clay were discussed. The results show that mineral composition and micro-structural changes may be the major factors accounting for the difference between physical and mechanical properties of the undisturbed and remolded red clay. The soil-water characteristics curve of undisturbed unsaturated red clay show three stages,which has the obvious air-entry values and residual moisture content,while the soil-water characteristics curve of remodeled unsaturated clay presents a semi-parabolic variation. For the undisturbed red clay,the maximum cohesion occurs in a low moisture condition,and the corresponding moisture content is about 5% to 10% larger than the residual moisture content. Thus,in this case,increasing the number of test groups can optimize the test results. For the remolded red clay,the range of the significantly reduced internal friction angle can be determined according to the plastic limit.