论文部分内容阅读
渗透系数(K)是水文地质、岩土工程领域的重要参数,而低渗透介质的结构较为复杂,在实际应用中,场地的尺度、介质的扰动程度等均会对K的确定产生影响.利用δ~(18) O化学示踪法、室内试验及经验公式法估算饱和黏性土的垂向渗透系数,并对比分析不同预测方法的适用性.以苏北沿海平原第四纪厚层黏土为例,δ~(18) O化学示踪法预测厚层黏性土的渗透系数低于10~(-11) m/s,室内法测得渗透系数为2.61×10~(-8)~9×10~(-12) m/s,经验法预测值较大,是室内法的几倍到几十倍.δ~(18) O化学示踪法是表征天然条件下长时间的实验结果,除了反映数十米厚层黏性土的等效渗透性能,还可预测黏土孔隙水的渗流时间;结合测定黏土样品液塑限等室内实验参数,室内实验和经验公式法可以提供系列剖面黏土的渗透系数,更清晰地说明厚层黏土剖面不同渗透系数预测方法的差异性.
The permeability coefficient (K) is an important parameter in the field of hydrogeology and geotechnical engineering, and the structure of the low permeability medium is quite complicated. In practical applications, the scale of the site and the degree of disturbance of the medium all affect the determination of K. By using (18) O chemical tracing method, indoor experiment and empirical formula method were used to estimate the vertical permeability coefficient of saturated clay, and the applicability of different prediction methods was contrasted and analyzed.Considering the Quaternary thick clay in the coastal plain of North Jiangsu as Theδ ~ (18) O chemical tracing method predicts that the permeability coefficient of thick clay is less than 10 ~ (-11) m / s and the permeability coefficient measured by indoor method is 2.61 × 10 ~ (-8) ~ 9 × 10 ~ (-12) m / s, the prediction of the empirical method is larger, which is several times to several times of the indoor method.δ ~ (18) O chemical tracing method is a characterization of the experimental results of natural conditions for a long time, In addition to reflecting the equivalent permeability of thick clay of tens of meters, the seepage time of clay pore water can also be predicted. Combining with the laboratory experimental parameters of liquid and plastic limit determination of clay samples, indoor experiments and empirical formula method can provide a series of cross-section clay Permeability coefficient, a more clear description of thick clay cross-section different permeability coefficient prediction method of difference.