掺粉煤灰再生混凝土宏观及微观碳化性能研究

为了研究不同再生粗骨料掺量和不同粉煤灰掺量下再生混凝土的抗碳化性能以及经过一段时间碳化之后再生混凝土的性能变化,对不同粉煤灰掺量(0、20%、40%)与不同再生骨料掺量(0、50%、100%)的混凝土进行了室内碳化性能试验,并且对碳化前后的混凝土试件进行电镜扫描分析。研究表明:随着再生粗骨料与粉煤灰掺量的增加,再生混凝土的碳化深度增大,再生混凝土的碳化速度随着碳化时间的增长而降低,再生混凝土抗压强度越大,碳化深度越小,并根据试验结果进行拟合得出了经不同碳化时间后抗压强度与碳化深度之间的回归方程式。

Study on macroscopic and micro carbonation properties of fly ash regenerated concrete

In order to study the carbonation resistance of recycled concrete with different content of recycled coarse aggregate and different content of fly ash and the performance change of recycled concrete after a period of carbonation, this study carried out indoor carbonation test and electron microscope scanning analysis on samples with different content of fly ash (0%, 20%, and 40%) and different content of recycled aggregate (0%, 50%, and 100%). The results show that: the carbonation depth of recycled concrete increases with the increase of recycled coarse aggregate and fly ash content. The carbonation rate of recycled concrete decreases with the increase of carbonation time. The greater the compressive strength of recycled concrete, the smaller the carbonation depth, and the regression equation between compressive strength and carbonation depth after different carbonation time was obtained by fitting the experimental results.