壳层人造硅酸盐骨料是具有结构梯度和成分梯度的复合结构，内核为基体，壳层为增强相。壳层和内核通过水化产物的相互渗透、相互搭接在界面处融为一个整体，界面结合牢固。对不同掺量的砂加气混凝土（SAAC）粉末和粉煤灰加气混凝土（FAAC）粉末制备的硅酸盐骨料进行对比，发现壳层结构可提高人造硅酸盐骨料的筒压强度，壳层结构对SAAC系列骨料的筒压强度提高幅度达49.72%~80.50%；对FAAC系列骨料的筒压强度提高幅度为15.30%~25.74%。壳层与内核的最佳质量比为1：25，此时壳层厚度为68.09 μm，制备的壳层人造硅酸盐骨料的筒压强度比无壳时提高约25%。在砂浆基体相同，粗骨料体积份数相等的情况下，人造硅酸盐骨料混凝土比普通混凝土的抗压强度低6.38%，表观密度低20.74%，具有轻质高强的性能。
The artificial silicate aggregate has a gradational structure with a compositional gradient. This paper discusses the shell structure reinforced composite based silicate aggregate core. The interface between the shell and the core nakes them to form a whole by the hydration product overlap. The performances of the SAAC aggregate and the FAAC aggregate are compared, and it is shown that the shell structure could improve the cylinder compressive strength (CCS) of the artificial silicate aggregate. The CCS of the SAAC aggregate is enhanced by 49.72%-80.50%, and the CCS of the FAAC aggregate is enhanced by 15.30%-25.74% with the shell structure. The best weight ratio of the shell and the core is 1:25, with shell thickness of 68.09 μm. The CCS of the artificial silicate aggregate with the shell structure is enhanced by about 25% as compared with that without the shell structure. Compared the silicate aggregate concrete with the ordinary concrete in the same level mortar and volume of the aggregate, it is shown that the compressive strength of the silicate aggregate concrete is 6.38% lower than the ordinary concretes, and the apparent density of the silicate aggregate concrete is 20.74% lower than the ordinary concrete.
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