为了探讨水泥掺量Ps、水灰比W/C（W为水质量，C为水泥质量）、含水率w 等因素对水泥胶结钙质砂导热系数l的影响规律，基于热探针法测定了不同试验条件下水泥胶结钙质砂的导热系数，分析了各因素影响下导热系数的变化规律，运用电镜扫描技术阐释了上述变化趋势发生的微观机制；在此基础上，提出了考虑水泥掺量、水灰比、含水率3个因素共同影响的水泥胶结钙质砂导热系数计算模型。试验结果表明：（1）水泥胶结钙质砂的导热系数l显著大于天然钙质砂的l值，随着水泥掺量Ps的增加，l值递增，但增长幅度依次递减；（2）水泥胶结钙质砂导热系数l随含水率w 的增加而递增，呈正相关关系；水灰比W/C越大，l反而越小；（3）水泥胶结钙质砂内微孔隙大小、数量的变化从本质上决定了其宏观热传导特性，凝胶状水化产物连续填充其内部孔隙，引起其孔隙率降低，改善砂样内部传热，宏观表现为其导热系数l随着胶结程度的增加而递增；（4）综合考虑Ps、w、W/C的3个因素共同影响的水泥胶结钙质砂导热系数计算模型具有很好的适用性，相关系数R2 = 0.916 4。水泥胶结钙质砂

In order to investigate the influences of moisturecontent w

water cement ration W/C(W is water mass

C is cement mass) and cement content Ps on the thermal conductivity l of cement-bonded calcareous sand

thermal conductivity ofcement-bonded calcareous sand under different test conditions were determinedby thermal probe method. The change rule of thermal conductivity under theinfluence of various factors was analyzed

and the microcosmic mechanism of thechange trend was explained by scanning electron microscope (SEM). On thisbasis

a calculation model of the thermal conductivity of cement-bondedcalcareous sand

which takes into account the water content

water cement ratioand cement content

was proposed. The experimental results show that thethermal conductivity of cement-bonded calcareous sand is significantly higherthan that of natural calcareous sand. The l value offormer increases with increasing the cement content

but the increase ratedecreases in turn. The l value of cement-bondedcalcareous sand increases with increasing water content as positivecorrelation. However

a larger W/C leads to a smaller l. The results of SEM show that the macroscopic thermal conductioncharacteristics of cement-bonded sand depend on the variation of size andquantity of its micro-pores. The gel-like hydration product continuously fillsthe internal pores of the bonded sand

causing a reduction in porosity and therebyimproving internal heat transfer of the sand sample. At macro level

thethermal conductivity increases with the increase of degree of cementation.Finally

the novel calculation model for the thermal conductivityof cement-bonded sand having a comprehensive consideration for Ps

w

and W/C has a good applicability

whose coefficientof determination R2 is0.916 4.