福建省花岗岩残积填土的水力与热物理参数分析

为确定花岗岩残积填土的水力、热物理参数,以福建省典型花岗岩残积土为例,采用土壤湿度自记仪进行水平吸渗试验及变水头渗透试验测定水力参数,同时推导热物理参数计算公式.结果表明:福建省花岗岩残积土的水分扩散率、非饱和导水率与饱和度之间呈现显著的幂函数关系;饱和导水率与压实度呈非线性关系,压实效果对土的饱和导水率影响较为显著,同时存在一个临界压实度,当压实度达到该临界值时,一味通过提高压实度增强路堤的防渗能力效果不明显;考虑土体压实度和含水率的比热容计算式,及综合考虑颗粒组成、压实度和含水率的热导率计算式更符合花岗岩残积土的热物理参数特性.

Analysis on water and thermodynamic parameters for granite residual soil in Fujian

In order to determine the water movement parameters for unsaturated granite residual soil, horizontal infiltration test and variable head permeability test were carried out, and deduced the calculation formula of thermal property parameters and a case study of typical granite residual soil in Fujian province. The results have shown that the relationships between moisture diffusion of soil and saturation as the same as that between unsaturated hydraulic conductivity and saturation can be expressed by power function. That is a nonlinear relationship between compact degree and saturated hydraulic conductivity; the hydraulic conductivity can be significant impacted by compaction, while there is a critical compact degree, the anti-seepage ability of subgrade can be enhanced by raise compact degree before compact degree achieve the critical value; the calculation formula of heat capacity which considering water content and compaction degree, and the calculation formula of thermal conductivity by considering the particle composition, degree of compaction and the water content are more according with the thermal property parameters characteristics for granite residual soil in Fujian.