Liew M S, Aswin Muhammad, Danyaro Kamaluddeen Usman, Mohammed Bashar S, Al-Yacouby A M
Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 32610, Malaysia.
Departemen Teknik Sipil, Universitas Sumatera Utara, Medan 20155, Indonesia.
Materials (Basel). 2020 May 26;13(11):2428. doi: 10.3390/ma13112428.
In relation to the use of retrofit materials on damaged constructions, application on earthquake-resistant buildings, and for the strengthening and rehabilitation on weakened regions, there is a need for a more superior material than concrete. Application sites include beam-column joints, corbels, link-slabs, deep beams, support regions and dapped-end areas. Fiber reinforced engineered cementitious composites (FR-ECC) can address this issue, because FR-ECC is one of the composite materials that has high strength, ductility and durability. In order to develop FR-ECC, this study was done to investigate the effect of adding quartz powder on the compressive strength capacity and properties of FR-ECC through the use of polyvinyl alcohol (PVA) and steel fibers. The volume fraction of fiber was set to 0%-2%. To support the friendly environment, FR-ECC uses by-product materials such as fly ash and silica fume, with a cement content less than 600 kg/m. In terms of the experimental investigation on FR-ECC, this work conducted the fresh property tests showing that PVA fibers have quite an influence on ECC workability, due to their hydrophilic behavior. By adjusting the superplasticizer (SP) content, the consistency and high workability of the ECC mixes have been achieved and maintained. The test results indicated that the PVA and steel fibers-based ECC mixes can be classified as self-compacting composites and high early compressive strength composites. Significantly, addition of quartz powder into the ECC mixes increased the compressive strength ratio of the ECC samples up to 1.0747. Furthermore, the steel fiber-based ECC samples exhibited greater compressive strength than the PVA fibers-based ECC samples with the strength ratio of 1.1760. Due to effect of the pozzolanic reaction, the fibers dispersion and orientation in the fresh ECC mixes, so that the cementitious matrices provided the high strength on the FR-ECC samples. During the compression loading, the bulging effect always occurred before the failures of the fibers-based ECC samples. No spalling occurred at the time of rupture and the collapse occurred slowly. Thus, FR-ECC has provided unique characteristics, which will reduce the high cost of maintenance.
关于在受损建筑上使用翻新材料、应用于抗震建筑以及对薄弱区域进行加固和修复，需要一种比混凝土更优质的材料。应用部位包括梁柱节点、牛腿、连接板、深梁、支撑区域和变截面端部区域。纤维增强工程水泥基复合材料（FR-ECC）可以解决这个问题，因为FR-ECC是具有高强度、延性和耐久性的复合材料之一。为了开发FR-ECC，本研究通过使用聚乙烯醇（PVA）和钢纤维来研究添加石英粉对FR-ECC抗压强度能力和性能的影响。纤维体积分数设定为0%-2%。为了支持环保，FR-ECC使用粉煤灰和硅灰等副产品材料，水泥含量低于600 kg/m³。就FR-ECC的试验研究而言，本工作进行了新拌性能试验，结果表明PVA纤维因其亲水性行为对ECC工作性有相当大的影响。通过调整高效减水剂（SP）含量，实现并保持了ECC混合料的稠度和高工作性。试验结果表明，基于PVA和钢纤维的ECC混合料可归类为自密实复合材料和高早期抗压强度复合材料。值得注意的是，向ECC混合料中添加石英粉使ECC样品的抗压强度比提高到1.0747。此外，基于钢纤维的ECC样品表现出比基于PVA纤维的ECC样品更高的抗压强度，强度比为1.1760。由于火山灰反应、纤维在新鲜ECC混合料中的分散和取向的影响，水泥基体为FR-ECC样品提供了高强度。在压缩加载过程中，基于纤维的ECC样品在破坏前总是会出现鼓胀效应。破裂时没有发生剥落，坍塌缓慢发生。因此，FR-ECC具有独特的特性，这将降低高昂的维护成本。
