摘要
黄土是具有特殊结构性的土,目前对其结构性影响因素的研究大多处于单因素定性分析阶段。构度指标反映的是黄土的初始结构性。为研究物理指标对初始结构性的综合影响,首先,对西安、兰州两地原状及重塑的黄土试样开展了不同含水率下的无侧限抗压强度试验,得到了相应黄土的构度。分析得出:构度随含水率、干密度、最小密度比、塑性指数、液性指数的增大均呈减小的趋势,除此之外,还与黄土的形成时代及其分布地区有关。其次,根据以上结论,用基本物理指标构造了一个综合物理量,进一步分析了构度与综合物理指标的关系,得出了区分地区、区分地质时代的由综合物理量直接定量计算构度指标的经验公式。最后,通过对西安另一场地的黄土进行试验得出的构度指标与运用本经验公式计算所得的构度值的对比,初步验证了其合理性、适用性。经验公式为以后通过简单易测的物理指标定量计算构度提供了一种方法。
Loess is a soil with a special structure. Currently the studies of influence factors on loess structure are mostly qualitative analysis using single factor. Structural index reflects the initial structure of loess. To study the influence of the physical parameters on the initial structure, firstly, unconfined compressive strength tests are conducted on the undisturbed and remolded loess samples with different water content taken from Xi＇an and Lanzhou. Next, the corresponding structural indexes of loess are obtained. The analysis shows that the value of structural index decreases with the increasing of water content, dry density, minimum density ratio, plasticity index and liquidity index. In addition, it is also related with the geological period and geographical distribution of loess. Secondly, according to the above conclusions, a comprehensive physical index is constructed by the fundamental physical indexes. The relationship between the structure and the comprehensive physical index is further analyzed. The empirical formulas are obtained which can directly calculate structure index quantitatively by the comprehensive physical index considering the distinction between the geographical zonation and geological periods. Finally, by the comparisons of the structure indexes obtained by test for another loess field in Xi＇an and the structure indexes calculated by the empirical formulas herein, their rationality and applicability are verified. These formulas provide a simple and easy method for quantitative calculation of the structural index by physical indexes to measure in the future.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2017年第12期3484-3490,共7页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.11572245
No.51608442)
陕西省科技厅基金(No.2014JQ5173)
陕西省教育厅科研计划项目资助(No.17JS089)~~
关键词
黄土
结构性
物理指标
定量计算
经验公式
loess
structure
physical index
quantitative calculation
empirical formula
作者简介
王丽琴，女，1976年生，博士，副教授，主妻从事岩土工植方面的教学与研究工作。E-mail：wanglq@xaut．edu.cn
