Insulating cementitious syntactic foams (CSFs) reinforced hollow glass microspheres (HGMs) have been paid much attention for the growing requirement of energy savings. In this paper, the CSF plates with different volume contents of HGMs are manufactured by a novel three-step manufacturing process and then they are tested by transient plane source (TPS) method to investigate their heat insulation performance. The filler volume content is in the range of 0–56 vol%. The experimental results reveal that the effective value of thermal conductivity of the foam decreases roughly linearly with increasing the HGM volume content. The addition of 56 vol% HGMs brings over 47% decrease of the thermal conductivity of the foam, in contrast to the pure cement material. In addition, the heat transfer mechanisms in the CSFs are further investigated by the developed computational model with randomly dispersed HGMs to approximate the real arrangement of microspheres in the foam. The experimental data are in good agreement with the numerical estimations. Moreover, the resulting numerical predictions demonstrate that the effective thermal conductivity coefficient of the foam increases as the constituent thermal conductivity increases. However, compared to the core and solid wall material, the matrix material gives significant influence to the foam. Finally, a two-phase composite model with equivalent solid spherical inclusion is presented based on Eshelby’s equivalent inclusion theory to indirectly determine the thermal conductivity of pure HGM, which are important for guiding the predesign of syntactic foams with desired low thermal conductivity.

绝缘胶结泡沫塑料（CSFs）增强的中空玻璃微球（HGMs）对于节能的日益增长的需求已引起了广泛关注。本文采用新颖的三步法制造了具有不同体积含量的HGM的CSF板，然后通过瞬态平面源（TPS）方法对其进行了测试，以研究其隔热性能。填料的体积含量为0-56％（体积）。实验结果表明，随着HGM体积含量的增加，泡沫的导热系数有效值大致呈线性下降。与纯水泥材料相比，添加56 vol％的HGM会使泡沫的热导率降低47％以上。此外，通过使用随机分散的HGM的计算模型进一步研究了CSF中的传热机理，以近似泡沫中微球的真实排列。实验数据与数值估计吻合良好。而且，所得的数值预测表明，泡沫的有效导热系数随组成导热系数的增加而增加。但是，与芯和实心壁材料相比，基体材料对泡沫有很大影响。最后，基于埃舍尔比的等效夹杂理论，提出了等效固体球形夹杂物的两相复合模型，用于间接确定纯HGM的导热系数，