中文摘要：

利用压汞法（MIP）测定混凝土的孔隙率,并结合气体在多孔介质中的扩散机制得出混凝土的复合扩散系数,再根据相关理论推导适用于Autoclam渗透测试仪的气体有效扩散系数计算公式,通过有效扩散系数与复合扩散系数的等式关系得到混凝土的孔曲折度。研究表明,龄期的延长和强度等级的增加能有效降低总孔隙率并降低锂渣混凝土的孔隙连通性,随着锂渣的掺入,C30、C60混凝土的孔隙率都有所增加且孔曲折度分别在锂渣掺量20%、30%时高于其空白组,从而降低了混凝土的孔连通性。

英文摘要：

The determination of porosity of concrete by mercury intrusion method （MIP） and the composite diffusion coefficient of concrete is obtained through the diffusion mechanism of gas in porous media.Based on the relevant theoretical derivation, the formula of effective diffusion coefficient of the gas is applied to the autoclam permeability tester,through the equality of the composite diffusion coefficient and the effective diffusion coefficient to calculate concrete pore tortuosity.The research suggests that the increase of curing age and compressive strength levels can effectively reduce the total porosity and decrease of lithium slag concrete pore connectivity, with the incorporation of lithium slag,the porosity of C30, C60 concrete has increased and the pore tortuosity respectively in lithium slag content 20% and 30% is higher than that of control group, thereby reducing the concrete pore connectivity.