当前位置: X-MOL 学术Cement Concrete Comp. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Development of self-stressing Engineered Cementitious Composites (ECC)
Cement and Concrete Composites ( IF 10.5 ) Pub Date : 2021-01-11 , DOI: 10.1016/j.cemconcomp.2021.103936
He Zhu , Duo Zhang , Yichao Wang , Tianyu Wang , Victor C. Li

While high ductility Engineered Cementitious Composites (ECC) have demonstrated effectiveness for infrastructure repair, the microcracking induced by the high material shrinkage may decrease the structural durability of ECC in aggressive environments. The objective of this research is to develop a self-stressing ECC, the expansion of which against the restraint of the repaired structure automatically induces pressure onto the repair material. Super absorbent polymer (SAP), shrinkage reducing agent (SRA), and calcium sulphoaluminate cement/expansive additive (CSA) were utilized together with Portland cement to tailor the composite expansion and expansive pressure. Free drying expansion/shrinkage, restrained expansive stress, and tensile performance were examined through standard shrinkage measurement, steel ring restrain test, and uniaxial tensile test, respectively. It was found that the 28 days drying shrinkage was decreased by 47% due to the use of SRA but was slightly increased when SAP was used. Substituting 42% of OPC with CSA (K42) increased ECC strength and ductility. The K42-ECC experienced a maximum expansion of 3756 με at 3 days and retained 2026 με expansion at 28 days. However, the expansion loss between 3 days and 28 days counteracted the expansive pressure. The deliberate combination of SRA and CSA provides a self-stressing effect tailoring the maximum expansion and expansion loss. The self-stressing performance along with a 7% ultra-high strain capacity and average crack width of 35–44 μm at 3% strain promotes the developed ECC as a more durable material for infrastructure repair.



中文翻译:

自应力工程水泥基复合材料(ECC)的开发

尽管高延展性的工程水泥复合材料(ECC)已证明对基础设施修复有效,但高材料收缩率引起的微裂纹可能会降低ECC在侵蚀性环境中的结构耐久性。这项研究的目的是开发一种自应力ECC,其扩展性在修复结构的约束下会自动在修复材料上产生压力。高吸水性聚合物(SAP),减缩剂(SRA)和硫铝酸钙水泥/膨胀剂(CSA)与硅酸盐水泥一起使用以调整复合材料的膨胀和膨胀压力。通过标准收缩率测量,钢环约束测试,自由干燥膨胀/收缩,约束膨胀应力和拉伸性能进行了检查,和单轴拉伸试验。发现由于使用SRA,28天的干燥收缩减少了47%,但是当使用SAP时,干燥收缩稍微增加了。用CSA(K42)代替42%的OPC可提高ECC强度和延展性。K42-ECC在第3天经历了最大扩展3756με,在第28天保持了2026με的扩展。但是,3天到28天之间的膨胀损失抵消了膨胀压力。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。发现由于使用SRA,28天的干燥收缩减少了47%,但是当使用SAP时,干燥收缩稍微增加了。用CSA(K42)代替42%的OPC可提高ECC强度和延展性。K42-ECC在第3天经历了最大扩展3756με,在第28天保持了2026με的扩展。但是,3天到28天之间的膨胀损失抵消了膨胀压力。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。结果发现,由于使用了SRA,28天的干燥收缩率降低了47%,而使用SAP时则略有增加。用CSA(K42)代替42%的OPC可提高ECC强度和延展性。K42-ECC在第3天经历了最大扩展3756με,在第28天保持了2026με的扩展。但是,3天到28天之间的膨胀损失抵消了膨胀压力。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损失。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。用CSA(K42)代替42%的OPC可提高ECC强度和延展性。K42-ECC在第3天经历了最大扩展3756με,在第28天保持了2026με的扩展。但是,3天到28天之间的膨胀损失抵消了膨胀压力。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。用CSA(K42)代替42%的OPC可提高ECC强度和延展性。K42-ECC在第3天经历了最大扩展3756με,在第28天保持了2026με的扩展。但是,3天到28天之间的膨胀损失抵消了膨胀压力。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。SRA和CSA的故意组合可提供自应力效果,以量身定制最大的膨胀和膨胀损耗。自应力性能以及7%的超高应变能力和3%应变时35-44μm的平均裂纹宽度,促进了已开发的ECC作为一种更耐用的基础设施维修材料。

更新日期:2021-02-01
down
wechat
bug