橡胶集料水泥砂浆和混凝土的性能研究

废轮胎颗粒掺加到水泥砂浆和混凝土中会明显降低材料强度,大大限制其应用。针对该问题,应用多种方法来改进橡胶混凝土的力学性能,例如降低W/C、掺加硅灰、偶联剂预处理橡胶颗粒等。研究结果表明，降低W/C能够明显提高橡胶混凝土的强度,橡胶颗粒表面用PVA和硅烷偶联剂处理能够显著增加抗压强度，如果多种方法联合使用效果更好。此外，橡胶改性混凝土的强度虽然有所降低，但其韧性和抗疲劳特性却显著增加。应用SEM分析了橡胶混凝土的微观结构,结果同样证实偶联剂处理橡胶颗粒表面能够提高水泥基体与橡胶颗粒的界面粘结强度。

Study on the properties of Portland cement mortar and concrete containing crumb rubber aggregate

Rubber-modified Portland cement Concrete (RMC) was made by using small rubber particles from waste tires to replace some portions of natural sand.The added rubber particles reduce the strength of RMC,which greatly limits the applications of RMC.Several methods were used in this study to improve mechanical properties of RMC,such as lower water-cement ratio(W/C),the addition of silica fume,and the pretreatment of rubber particles by coupling agents,PVA and silane.Test results showed that a low W/C ratio significantly increases the strength of RMM.Both PVA and silane are very effective in improving the compressive strength of RMM.The compressive strength of RMM can be further improved by using a combination of methods such as having a low W/C ratio and pretreatment of rubber surface by a coupling agent.Although the strength of RMC decreased,the toughness and fatigue resistance obviously increased.The microstructure of RMC were analyzed by SEM,and the SEM results showed that the interfaces between rubber particles and cement paste matrix are improved significantly by using the pretreatments of silane and PVA.