废弃玻璃对混凝土ASR膨胀的影响研究

Effect study of waste glass on ASR expansion of concrete

为了研究废弃玻璃对混凝土ASR膨胀的影响,采用ASTMC1260快速砂浆棒法测取砂浆棒不同龄期的膨胀率,采用扫描电子显微镜(SEM)对砂浆棒微观结构进行对比,分析了玻璃粉、玻璃砂掺量以及玻璃粉粒径大小等因素对混凝土ASR膨胀的影响。研究结果表明:各砂浆棒试件的膨胀率基本随着龄期的增长而增大;在单一掺料下,与对照组相比,玻璃砂会增大ASR膨胀,而玻璃粉能较好地抑制ASR膨胀;当同时掺入玻璃砂和玻璃粉时,适当掺量的玻璃砂和玻璃粉能较好地抑制ASR膨胀,当玻璃粉掺量少或者玻璃砂掺量较大时,对ASR膨胀的抑制效果会减弱;玻璃粉粒径为0~13μm、13~38μm、38~75μm的砂浆膨胀率随龄期的增长趋势相当,但膨胀率基本随着玻璃粉粒径的减小而减小,可以较好地抑制ASR膨胀。

In order to study the effect of waste glass on concrete’ s ASR expansion,the expansion rates of mortarrods at different ages were measured by ASTMC1260 rapid mortar rod method,the microstructure of mortar rods was compared by scanning electron microscopy( SEM),which were contributed to analyzing the effect of content of glass powder,glass sand and factors as glass powder particle size on concrete’ s ASR expansion. The results show that,the expansion rate of each mortar rod specimen increases with age. Under the condition of single admixture,glass sand boosts the ASR expansion compared,while the glass powder can better inhibit ASR expansion compared to the control group. When glass sand and glass powder were simultaneously incorporated,a appropriate amount can better inhibit ASR expansion,and when the amount of glass powder is small or the amount of glass sand is large,the inhibition effect on ASR expansion will be weakened. The mortar’s expansion ratio of the glass powder with particle size of 0 ~ 13μm,13 ~ 38μm,38 ~ 75μm is similar with the growth trend of the age,but the expansion rate decreases with the decrease of the glass powder particle size,which can inhibit ASR expansion effectively.