试验分析了5种温度梯度下玻化微珠保温混凝土的外观形貌和质量损失，利用扫描电镜（SEM ）观察5种温度等级和两种不同冷却方式下保温混凝土的微观结构，定性分析微观物相对质量损失和裂缝开展的影响。试验结果表明：在100～500℃下，保温混凝土中保温骨料玻化微珠性能稳定；经历温度低于300℃时，保温混凝土孔内水分蒸发，质量损失率为4.36％，但基本不出现裂缝；经历温度为300～500℃时，保温混凝土中C‐S‐H凝胶结构和Ca （O H ）2晶体由于失去水分而分解，质量损失率为6.22％，裂缝越来越多；浇水冷却方式下，保温混凝土内部发生水化反应生成 C‐S‐H凝胶和Ca（OH）2晶体，将孔隙填的更加密实，故其裂缝开展小于自然冷却下的裂缝开展。%The morphology and mass loss at five temperature gradients of glazed hollow bead thermal insulation concrete were analyzed ,its micro‐structure was characterized by scanning elec‐tron microscopy(SEM) for five temperature ratings and two cooling modes .The effect of micro‐scopic objects on mass loss and crack development was analyzed .The results indicate that :at 100~500 ℃ ,the performance of glazed hollow bead is stable ;after exposed to less than 300 ℃ ,be‐cause of water evaporation of thermal insulation concrete ,the mass loss rate is 4.36% and almost no cracks occur on concrete ;when exposed to 300~500 ℃ ,C‐S‐H structures and Ca(OH)2 crys‐tals decompose owing to release of moisture ,the mass loss rate is 6.22% ,and more cracks occur on concrete with the increase in temperature ;with water cooling ,thermal insulation concrete oc‐curs new chemical reactions generating C‐S‐H structures and Ca(OH)2 crystals ,filling the pores , so the cracks are less than with natural cooling .
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