全级配煤矸石混凝土导热性能试验与分析

为研究和预测全级配煤矸石混凝土的导热性能,以五种不同的煤矸石粗骨料替代率(0、25％、40％、70％、100％)和四种煤矸石细骨料替代率(25％、50％、75％、100％)设计9组试验,对煤矸石混凝土导热性能进行试验.结果 表明:煤矸石粗骨料替代率越高,煤矸石混凝土导热系数就越低;煤矸石粗骨料替代率为100％情况下,随着煤矸石细骨料替代率增加,煤矸石混凝土导热系数继续降低,其中全级配煤矸石混凝土导热系数最低,相比普通混凝土导热系数的下降幅度为52.56％;定义了煤矸石骨料影响系数M,M值越大,混凝土导热系数越低;对Hasselman-Johnson混凝土导热系数计算模型进行修正,得到煤矸石混凝土导热系数的修正计算模型,修正计算值与试验结果相吻合.

Experiment and study of thermal conductivity offull grade coal gangue concrete

In order to analyze and predict the thermal conductivity of full grade coal gangue concrete, nine groups of tests were designed with five different substitution rates of coarse gangue aggregate (0, 25%, 50%, 75%, 100%) and four different substitution rates fine gangue aggregate (25%, 50%, 75%, 100%). The results show that the higher the replacement rate of coal gangue coarse aggregate is, the lower the thermal conductivity of concrete will be; when the replacement rate of coal gangue coarse aggregate is 100%, the thermal conductivity of coal gangue concrete will continue to decrease with the increase of the replacement rate of coal gangue fine aggregate, among which the thermal conductivity of full grade coal gangue concrete is the lowest, which is 52.56% lower than that of ordinary concrete; coal gangue aggregate impact factor M is defined, and the larger the M, the lower the thermal conductivity of concrete is; the modified calculation model of thermal conductivity of coal gangue concrete is obtained by modifying the Hasselman-Johnson thermal conductivity calculation model, and the modified calculation results are in good agreement with the test values.