Deterioration Mechanism of Recycled Composite Powder Concrete under Dry‑Wet Cycles of Sulfate

被引：0

作者：

Liu C. ^{[1
,2
]}

Yao Y. ^{[1
]}

Liu H. ^{[1
]}

Hu T. ^{[1
]}

机构：

[1] School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an

[2] School of Science, Xi'an University of Architecture and Technology, Xi'an

来源：

Jianzhu Cailiao Xuebao/Journal of Building Materials | 2022年 / 25卷 / 11期

关键词：

dry‑wet cycle; microstructure; recycled composite powder concrete; sulfate attack;

D O I：

10.3969/j.issn.1007-9629.2022.11.004

中图分类号：

学科分类号：

摘要：

Recycled composite powder concrete was prepared by mixing recycled brick powder and recycled concrete powder to replace part of the cement. Sulfate attack tests and microstructure characterization under dry‑wet cycles were carried out to analyze the pore structure parameters and the evolution process of interfacial transition zone. Based on its microstruture evolution process， SO 4 2 - attack model was established， which revealed the deterioration mechanism of recycled composite powder conclete under sulfate attack. The results show that compressive strength loss rate of the recycled composite powder concrete decreases and then increases with the increase of the number of dry‑wet cycles， and the change is greater with the increase of the replacement rate of recycled composite powder. The recycled composite powder with low replacement rate has played a better role in filling effect and nucleation to promote cement hydration， but the initial defect of high porosity provides a large number of attack channels， which is the main reason for the accelerated deterioration of the durability performance of recycled composite powder concrete. © 2022 Tongji University. All rights reserved.

引用

页码：1128 / 1135

页数：7

共 18 条

[1] XIAO J Z, MA Z M, SUI T B, Et al., Mechanical properties of concrete mixed with recycled powder produced from construction and demolition waste［J］, Journal of Cleaner Production, 188, (2018)
[2] SUN C, CHEN L L, XIAO J Z, Et al., Compound utilization of construction and industrial waste as cementitious recycled powder in mortar［J］, Resources， Conservation and Recycling, 170, (2021)
[3] TANG Q, MA Z M, WU H X, Et al., The utilization of eco‑friendly recycled powder from concrete and brick waste in new concrete：A critical review［J］, Cement and Concrete Composites, 114, (2020)
[4] ZHAO Y S, GAO J M, LIU C B, Et al., The particle‑size effect of waste clay brick powder on its pozzolanic activity and properties of blended cement［J］, Journal of Cleaner Production, 242, (2020)
[5] LIU Chao, HU Tianfeng, LIU Huawei, Et al., Effect of recycled composite micro‑powder on mechanical properties and microstructure of concrete［J］, Journal of Building Materials, 24, 4, (2021)
[6] WU H X, YANG D Y, XU J G, Et al., Water transport and resistance improvement for the cementitious composites with eco‑friendly powder from various concrete wastes［J］, Construction and Building Materials, 290, (2021)
[7] MA Z M, LI W, WU H X, Et al., Chloride permeability of concrete mixed with activity recycled powder obtained from C&D waste［J］, Construction and Building Materials, 199, (2019)
[8] GAO Rundong, Micro‑macro degradation regularity of sulfate attack on concrete under complex environments［D］, (2010)
[9] XIE F, LI J P, ZHAO G W, Et al., Experimental investigations on the durability and degradation mechanism of cast‑in‑situ recycled aggregate concrete under chemical sulfate attack［J］, Construction and Building Materials, 297, 5, (2021)
[10] LIKES L, MARKANDEYA A, HAIDER M M, Et al., Recycled concrete and brick powders as supplements to Portland cement for more sustainable concrete［J］, Journal of Cleaner Production, 364, (2022)

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