摘要
绿色延性水泥基复合材料(green toughness cementitious composities,GTCC),是借鉴高延性水泥基复合材料(engineered cementitious composites,ECC)技术开发的一款聚乙烯醇((polyvinly alcohol,PVA)纤维增强尾矿砂水泥基复合材料,该复合材料以大比例尾矿砂替代天然细骨料,具有经济、环保和延性特性。目前对于该复合材料的研究主要局限于产品制备、力学性能和耐久性等方面,有关GTCC裂缝自愈合性能的研究至今尚未见报道。为了探究该复合材料的自愈合性能,设计了尾矿砂替代天然砂比率为50%的3组不同水胶比的立方体试件,采用抗压强度恢复率法对GTCC的自愈合性能进行了研究,研究了损伤龄期、养护龄期、养护环境及干湿循环周期等因素对该新型材料自愈合效果的影响,揭示了绿色延性水泥基复合材料在不同条件下的自愈合规律。结果表明:该复合材料的损伤龄期越早,其自愈合效果越好;其自愈合效果随着自愈合养护龄期的增加而增加,但后期增长率较早期增长率越来越弱;干湿循环养护环境相对其它环境,更有利于其自愈合发生;自愈合作用主要发生在21个干湿循环之前。
Green toughness cementitious composites(GTCC)is one kind of polyvinly-alcohol(PVA)fiber-reinforced tailing sand engineered cementitious composites,which was developed by engineered cementitious composites(ECC)technology.The composite replaces natural fine aggregate with a large proportion of tailing sand,which has the characteristics of economy,environmental protection and ductility.At present,the research on this composite material is mainly confined to the aspects of product preparation,mechanical properties and durability.The research on the self-healing property of GTCC cracks has not been reported yet.In order to explore the self-healing properties of the composites,three groups of cube specimens containing 50% tailings sand and 50% natural sand with different water-binder ratios were designed,the self-healing properties of GTCC were studied by compressive strength recovery method.Through the compressive strength experiment,the influences of damage age,self-healing age,curing condition and cycles of wet-dry conditioning on the self-healing effect of the new material were discussed.The results show that the earlier the composite material is damaged,the better the self-healing effect is.The self-healing effect increases with the increase of self-healing age,but the later growth rate is weaker than the early growth rate.The wet-dry conditioning is more conducive to its self-healing than other environment.Self-healing occurrs primarily before the 21st wet-dry cycles.
作者
鲍文博
王东旭
王怀成
BAO Wenbo;WANG Dongxu;WANG Huaicheng(School of Architecture and Civil Engineering,Shenyang University of Technology,Shenyang 110870,China)
出处
《中国材料进展》
CAS
CSCD
北大核心
2019年第4期396-400,共5页
Materials China
基金
辽宁省教育厅科学基金项目(LGD2016007)
