缓凝剂对快硬修补砂浆性能的影响  

Influence of retarder on the performance of rapid-hardening repair mortar

作　　者：谭盐宾[1,2] 王浩 郑永杰 李林香[1,2] 杨鲁[1,2] 付志勇 吴俊杰[1] TAN Yanbin;WANG Hao;ZHENG Yongjie;LI Linxiang;YANG Lu;FU Zhiyong;WU Junjie(China Academy of Railway Sciences Railway Engineering Research Institute,Beijing 100081,China;State Key Laboratory for Track Technology of High-Speed Railway,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院铁道建筑研究所,北京100081 [2]高速铁路轨道技术国家重点试验室,北京100081

出　　处：《混凝土》2018年第10期123-126,共4页Concrete

基　　金：国家自然基金(51408611);中国铁路总公司重点科研项目(2017G005-D)

摘　　要：以白色双快硫铝酸盐水泥为胶凝材料制备早强快硬修补砂浆材料,研究了缓凝剂种类和掺量、减水剂掺量和和易性调节剂等对修补砂浆工作性能、力学性能、拉伸黏结强度和自由膨胀率的影响规律。结果表明:随着柠檬酸和硼砂掺量的增加,新拌砂浆扩展度呈单峰变化趋势,前者的掺加能有效控制新拌砂浆的可工作时间,而硼砂与该体系的胶凝材料适应性较差;随着柠檬酸掺量增加,硬化砂浆早期抗压和抗折强度均呈逐渐降低趋势;未掺加柠檬酸的硬化砂浆7 d拉伸黏接强度为1.32 MPa,柠檬酸掺量为0.45%的硬化砂浆7 d拉伸黏接强度为0.89 MPa;对于未掺加柠檬酸硬化砂浆的各龄期自由膨胀率均大于掺量为0.45%的硬化砂浆。Therapid-hardening repair mortar was made by white double-hardened sulphoaluminate cement,which is regarded as binding material.The influence of variety and dosage of retarder,dosage of water reducer,amiability modifier on the workability,mechanical properties,tensile bond strength and free swelling ratio of rapid-hardening repair mortar were studied.The result shows that:the mortar expansion presented single peak variation tendency with the dosage of citric acid(CA)and borax(PS)increasing.Former could control the operable time of fresh mortar effectively,however,the PS had poorer flexibility on this binding material.The compressive and flexural strength of hardened mortar before 24 h were gradually decreased with the dosage of CA increasing.The tensile bond strength was 1.32 MPa at 7 d without adding CA,by contrast was 0.89 MPa with the 0.45%dosage of CA.The free swelling ratio of the hardened mortar without adding CA was bigger than the 0.45%dosage of CA at any age.

关 键 词：快硬修补砂浆 缓凝剂 力学性能 拉伸黏接强度 自由膨胀率 

分 类 号：TU528.042.3[建筑科学—建筑技术科学]