红黏土有效孔隙小于实际孔隙,导致传统Darcy渗透公式计算值较实际值偏大,研究红黏土有效孔隙比的计算方法对红黏土的渗透系数计算具有重要意义。介绍了稠度指标法、起始坡降法、双电层参数法、饱和土样质量法、结合水含量法、m指数法以及自行推导的击实度法等7种有效孔隙比的计算方法,并分析了其优缺点。计算不同有效孔隙比方法的Darcy渗透系数,结合56组变水头渗透试验结果,验证了有效孔隙比计算方法在红黏土中的适用性。结果表明,应根据红黏土渗透性的大小,选择不同的有效孔隙比计算方法。
The effective porosity is smaller than the actual pore in the lateritic soil.Thus the calculation result is larger by the traditional Darcy formula than the actual value.So it is important to study the calculation method of the effective void ratio of the lateritic soil.The consistency index method,initial gradient method,double layer parameter method,saturated soil quality,combined water content method,m index method,and the compaction degree method derived in this paper were introduced.Their advantages and disadvantages were analyzed.The applicability of the modified formula of Darcy permeability coefficient based on the effective void ratio in the lateritic soil was verified based on the experimental data of 56 groups of variable head permeability.The results show that the effective void ratio should be calculated by different methods according to the permeability of the lateritic soil.