表面改性橡胶水泥砂浆的力学性能试验研究

Experimental Study on the Mechanical Property of Cement Mortar with Modified Rubber

分别采用水、EP乳液、聚氨酯乳液、NPU乳液4种材料对橡胶表面进行特殊处理,研究其对橡胶水泥砂浆力学性能的影响。结果显示4种材料的处理方法均不同程度的提升了橡胶水泥砂浆的抗压强度,其中EP乳液改性效果最优,抗压强度较基准橡胶砂浆提高了15.745%;改性后的橡胶水泥砂浆的劈拉强度与未改性的橡胶水泥砂浆相比无明显降低;未处理和处理后的橡胶水泥砂浆,其拉压比均比基准普通水泥砂浆较大,其韧性有所提高。2000倍的电镜观测表明,改性后的橡胶颗粒表面能够提高水泥基体与橡胶颗粒的界面黏结强度,从微观上阐明了改性橡胶砂浆强度提高的机理。

This paper mainly analyzed the mechanical property of rubber cement mortar by adopting different modification methods of adding mixed water,EP emulsion,polyurethane emulsion,NPU emulsion respectively and many others. The result demonstrates that 4 different surface treatments could all enhance compressive strength of rubber cement mortar with EP emulsion having the best effect which has 15. 745% increased strength compared with standard rubber cement mortar; while the improved type has no apparent decrease in splitting tensile strength; tensile and compression ratio of non-modified and modified are larger than standard cement mortar,similar situation happens on its toughness. By observing 2000 X electron microscope it can be found that improved rubber surface can increase interface bond strength between cement and rubber particles,and expounds the mechanism why improved rubber-sand mud has higher strength at micro level.