摘要
从绿色经济角度出发,以获得较高韧性为目的,采用短切内掺及长纤维分层平铺两种制备工艺,通过单轴拉伸试验获得四种植物纤维增强水泥基材料的拉伸特性,并对材料成本进行分析。试验结果表明:内掺短切苎麻纤维与剑麻纤维试件虽表现出应变软化特征但在开裂后具有较好的应力水平保留率。竹原、大麻、剑麻及苎麻纤维分层平铺试件均表现出明显应变硬化特征且极限拉应变均达到2%以上,而剑麻纤维分层平铺试件拉伸性能优越且成本较低有利于进一步的研究与推广应用。
From the point of view of developing green and low cost materials,four kinds of vegetable fibers,including bamboo fiber, sisal fiber, hemp fiber and ramie fiber, were used to reinforce cementitious composites to get higher ductility. Specimens were casted with random short fiber and aligned long fiber. Direct tensile performance of specimens was tested and analyzed. Also the cost of materials was analyzed. The results show that specimens with short ramie and sisal fiber perform strain softening but better stress retention rate after cracking. Furthemore,all specimens with aligned long fiber perform strain hardening characteristics and the ultimate tensile strain can reach above 2%. In particular aligned long sisal fiber reinforced specimens show excellent tensile property and low cost,which would be more favorable to further development and application.
引文
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