Strength and Durability Characteristics of Coir, Kenaf and Polypropylene Fibers Reinforced High Performance Concrete

ABSTRACT

Cement concrete is used in small structure to big multi-storied buildings. It is noteworthy to concentrate on concrete elements and mix ratio to achieve desirable strength with feasible cost of raw material. In this investigation, fibers reinforced concrete specimens (M50 grade) were prepared. The strength and durability were tested and compared with the properties of plain concrete (PC). The fibers such as coir, kenaf, and Polypropylene (PP) were used as reinforcement and the compressive, split tensile, flexural, and durability analysis were performed. The compressive test resulted that the natural fiber-based PC/Coir & PC/PP-Coir specimens displayed the maximum compressive strength of 64.5 and 66 MPa owing to the small density and slighter water up taking properties of coir and PP fiber. The split tensile test showed that the PC/kenaf specimen exhibited the higher split tensile strength of 7.3 MPa due to the presence of kenaf fiber with high young’s modulus. Flexural test reported that the PC/PP-Coir/Kenaf specimen exhibited the higher flexural strength of 7.6 MPa because of reinforcing effect offered by coir, kenaf, and PP fibers. Durability study showed that the PC/PP and PC/PP-coir specimens displayed the minimum weight loss of 1.05 and 2.1% and the minimum loss in compressive strength of 3.4 and 4.6%, respectively, in alkaline medium. It was concluded from this study that the coir fiber could be a suitable candidate to improve the strength and durability of concrete.

摘要

水泥混凝土用于小型结构到大型多层建筑. 值得注意的是，要在原材料成本合理的情况下，集中精力研究混凝土成分和配合比，以达到理想的强度. 在本研究中，制备了纤维增强混凝土试件（M50级）. 对其强度和耐久性进行了测试，并与素混凝土进行了性能比较. 以椰壳纤维、红麻纤维和聚丙烯（PP）纤维为增强材料，进行了压缩、劈拉、弯曲和耐久性分析. 压缩试验结果表明，由于椰壳纤维和聚丙烯纤维的密度小、吸水性好，天然纤维基PC/Coir和PC/PP椰壳试样的最大压缩强度分别为64.5mpa和66mpa. 劈裂拉伸试验表明，由于红麻纤维具有较高的杨氏模量，PC/红麻试样具有较高的劈裂拉伸强度7.3mpa. 弯曲试验表明，由于椰壳纤维、红麻纤维和PP纤维的增强作用，PC/PP椰壳纤维/红麻纤维的弯曲强度达到7.6mpa. 耐久性研究表明，PC/PP和PC/PP椰壳试样在碱性介质中的最小失重率分别为1.05%和2.1%，抗压强度的最小失重率分别为3.4%和4.6%. 研究结果表明，椰壳纤维是提高混凝土强度和耐久性的理想材料.

KEYWORDS:

• Hybrid fiber concrete
• coir fiber
• kenaf fiber
• polypropylene fiber
• mechanical properties
• durability characteristics

关键词:

• 混杂纤维混凝土
• 椰壳纤维
• 红麻纤维
• 聚丙烯纤维
• 机械性能
• 耐久性特征