TY - JOUR

T1 - Thermally-induced mechanical degradation analysis of recycled aggregate concrete mixed with glazed hollow beads

AU - Li, Beibei

AU - Zhang, Yu

AU - Selyutina, Nina

AU - Smirnov, Ivan

AU - Deng, Kezhao

AU - Liu, Yuanzhen

AU - Miao, Yanchun

N1 - Funding Information: This work was supported by the National Natural Science Foundation of China (Grant numbers 51808375, 5201101735, and 51911530238), the Russian Foundation for Basic Research (Project number 21-51-53008), the Natural Science Foundation of Shanxi Province, China (Grant numbers 201901D211018 and 201901D211108), and the Foundation of State Key Laboratory of Subtropical Building Science, China (Grant number 2019ZB23). Funding Information: This work was supported by the National Natural Science Foundation of China (Grant numbers 51808375 , 5201101735 , and 51911530238 ), the Russian Foundation for Basic Research (Project number 21-51-53008), the Natural Science Foundation of Shanxi Province, China (Grant numbers 201901D211018 and 201901D211108 ), and the Foundation of State Key Laboratory of Subtropical Building Science , China (Grant number 2019ZB23 ). Publisher Copyright: © 2021 Elsevier Ltd

PY - 2021/9/27

Y1 - 2021/9/27

N2 - The occurrence of fire often leads to the damage and deterioration of micro-and meso-structures of concrete materials, leading to the decomposition of hydrates, coarsening of porous structure, and thermal cracking induced by water vapor pressure, resulting in the decline of macro-physical and mechanical properties and durability. The meso-regulatory function of the lightweight, high-strength, internally porous and thermally stable glazed hollow beads (GHB) can improve the high-temperature resistance of concrete. In order to study the degradation characteristics of recycled aggregate concrete mixed with glazed hollow beads (RATIC), mechanical properties and internal meso-structural changes at high temperatures, the cube compressive strength test and CT test are carried. According to the improved image segmentation algorithm based on adaptive threshold and region growing methods, the influence of different recycled coarse aggregate (RCA) and GHB contents on the mesostructure of RATIC, such as thermal crack development and pore distribution, is systematically analyzed. Based on the self-compiled box dimension program, the corresponding relationship between compressive strength, fractal dimensions of mesostructure and temperature is obtained. The results reveal that the GHB can alleviate the stress concentration of coarse aggregates and cement paste caused by temperature expansion and deformation, provide a release channel for vapor pressure, alleviate cracks in the mortar area and pore boundaries, and slow down the spread of heat in the concrete. Overall, the GHB renders a positive effect on the heat-induced damage resistance of concrete.

AB - The occurrence of fire often leads to the damage and deterioration of micro-and meso-structures of concrete materials, leading to the decomposition of hydrates, coarsening of porous structure, and thermal cracking induced by water vapor pressure, resulting in the decline of macro-physical and mechanical properties and durability. The meso-regulatory function of the lightweight, high-strength, internally porous and thermally stable glazed hollow beads (GHB) can improve the high-temperature resistance of concrete. In order to study the degradation characteristics of recycled aggregate concrete mixed with glazed hollow beads (RATIC), mechanical properties and internal meso-structural changes at high temperatures, the cube compressive strength test and CT test are carried. According to the improved image segmentation algorithm based on adaptive threshold and region growing methods, the influence of different recycled coarse aggregate (RCA) and GHB contents on the mesostructure of RATIC, such as thermal crack development and pore distribution, is systematically analyzed. Based on the self-compiled box dimension program, the corresponding relationship between compressive strength, fractal dimensions of mesostructure and temperature is obtained. The results reveal that the GHB can alleviate the stress concentration of coarse aggregates and cement paste caused by temperature expansion and deformation, provide a release channel for vapor pressure, alleviate cracks in the mortar area and pore boundaries, and slow down the spread of heat in the concrete. Overall, the GHB renders a positive effect on the heat-induced damage resistance of concrete.

KW - переработанный бетон

KW - стеклянные полые шарики

KW - высокая температура

KW - прочность на сжатие

KW - фрактальные методы

KW - корреляционные характеристики

KW - CT images

KW - Compressive strength

KW - Correlation characteristics

KW - Fractal dimension

KW - Glazed hollow beads

KW - High temperature

KW - Recycled aggregate concrete

UR - http://www.scopus.com/inward/record.url?scp=85111557866&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/fe543662-9a6c-320c-ae92-f4e62184c41a/

U2 - 10.1016/j.conbuildmat.2021.124350

DO - 10.1016/j.conbuildmat.2021.124350

M3 - статья

VL - 301

JO - Construction and Building Materials

JF - Construction and Building Materials

SN - 0950-0618

M1 - 124350

ER -