Study on Durability and Pore Characteristics of Concrete under Salt Freezing Environment
| Autor: | Luo Tao, Yu Yi, Cheng Hua, Xinchao Zheng, Fang Liu, Yanfu Duan |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
concrete durability
Technology Materials science Salt (chemistry) pore characteristics Article industrial computed tomography General Materials Science Composite material Porosity chemistry.chemical_classification Microscopy QC120-168.85 QH201-278.5 Spall compressive strength Engineering (General). Civil engineering (General) Durability salt freezing TK1-9971 Compressive strength chemistry Volume (thermodynamics) Descriptive and experimental mechanics Frost (temperature) Electrical engineering. Electronics. Nuclear engineering Mortar TA1-2040 |
| Zdroj: | Materials, Vol 14, Iss 7228, p 7228 (2021) Materials; Volume 14; Issue 23; Pages: 7228 Materials |
| ISSN: | 1996-1944 |
| Popis: | The macroscopic mechanical properties and frost resistance durability of concrete are closely related to the changes in the internal pore structure. In this study, the two-dimensional and three-dimensional ICT (Industrial Computerized Tomography) pore characteristics of C30 concrete specimens before and after freezing and thawing in clean water, 5 wt.% NaCl, 5 wt.% CaCl2, and 5 wt.% CH3COOK solution environments are obtained through concrete frost resistance durability test and ICT scanning technology. The effects of pore structure changes on concrete frost resistance, durability, and compressive strength mechanical properties after freezing and thawing cycles in different salt solution environments are analyzed. This paper provides new means and ideas for the study of concrete pores. The results show that with the increase in the freezing and thawing times, the concrete porosity, two-dimensional pore area, three-dimensional pore volume, and pore number generally increase in any solution environment, resulting in the loss of concrete compressive strength, mortar spalling, and the decrease in the relative dynamic elastic modulus. Among them, the CH3COOK solution has the least influence on the concrete pore changes; the NaCl solution has the greatest influence on the change in the concrete internal porosity. The damage of CaCl2 solution to concrete is second only to the NaCl solution, followed by clean water. The increase in the concrete internal porosity from high to low is NaCl, CaCl2, clean water, and CH3COOK. The change in the pore volume of 0.1 to 1 mm3 after the freeze–thaw cycle is the main factor for reducing concrete strength. The test results have certain guiding value for the selection of deicing salt in engineering. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|