稻壳灰橡胶混凝土抗冻融性能及微观结构  

Freeze-thaw cycle and microstructure of rice husk ash rubber concrete

作　　者：王恒 徐义华 姚韦靖 庞建勇[1] 刘雨姗 WANG Heng;XU Yihua;YAO Weijing;PANG Jianyong;LIU Yushan(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,淮南232001

出　　处：《复合材料学报》2023年第5期2951-2959,共9页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(面上项目)(2108085ME158);安徽省高等学校自然科学研究项目(重点项目)(KJ2020A0297)。

摘　　要：为研究稻壳灰橡胶混凝土(RRC)的抗冻融性能,对比分析在氯盐环境下冻融循环后,普通混凝土(Normal concrete,NC)、橡胶混凝土(Rubber concrete,RC)和RRC的质量损失、相对动弹模量损失、强度损失及微观结构特征,同时对相对动弹模量与相对抗压强度的关系进行拟合分析。结果发现:随冻融循环次数增加,稻壳灰橡胶混凝土表面坑蚀愈明显,内部孔隙增多,微裂缝发展并贯通,宏观强度显著降低,相对动弹模量与抗压强度有良好相关性,拟合结果较优。橡胶的高弹性和稻壳灰极高的火山灰效应有效缓解了冻胀力带来的损伤,各冻融阶段RRC的损伤程度均明显优于NC,其中以稻壳灰掺量(占胶凝材料质量比)为10%、橡胶掺量(等体积取代砂)为10%时的RRC力学性能与抗冻融性能综合最优,经历120次冻融循环后,其抗压强度损失率较NC降低了18%。In order to study the freeze-thaw resistance of rice husk ash rubber concrete(RRC),the mass loss,relative dynamic modulus loss,strength loss and microstructure characteristics of normal concrete(NC)and RRC after freeze-thaw cycles in chloride environment were compared and analyzed,and the relationship between relative dynamic modulus and relative compressive strength was fitted and analyzed.The results show that with the increase of freeze-thaw cycles,the pit erosion on the concrete surface becomes more obvious,the internal pores increase,microcracks develop and penetrate,and the macroscopic strength decreases significantly.The relative dynamic modulus has a good correlation with the compressive strength,and the fitting structure is better.The high elasticity of rubber and high pozzolanic effect of rice husk ash effectively alleviate the damage caused by frost heaving force,and the damage degree of RRC in each freeze-thaw stage is significantly better than that of NC.When the content of rice husk ash(mass ratio to cementitious materials)is 10%and the content of rubber(volume replacement of sand)is 10%,the comprehensive optimum of mechanical properties and freeze-thawing resistance of RRC is the best.After 120 freeze-thaw cycles,the loss rate of compressive strength is 18%lower than that of NC.

关 键 词：稻壳灰 氯盐环境 冻融循环 火山灰效应 微观结构 

分 类 号：TU528[建筑科学—建筑技术科学] TB332[一般工业技术—材料科学与工程]