TY  - EJOU
AU  - Wang, Xuefeng 
AU  - Cao, Haiqing 
AU  - Jiao, Ke 
AU  - Li, Aoxiang 
AU  - Li, Zhongwei 

TI  - Hydration Heat Analysis and Crack Control of Composite Box Girders with Corrugated Steel Webs in Prefabrication
T2  - Structural Durability \& Health Monitoring

PY  - 2025
VL  - 19
IS  - 4
SN  - 1930-2991

AB  - This study examines the temperature field distribution characteristics and temperature effects during the prefabrication of composite box girders with corrugated steel webs (CBGCSWs), aiming to provide practical recommendations for controlling temperature-induced cracking and technical guidance for concrete mix proportions and placement processes. Based on field measurement data, a three-dimensional finite element model was developed to simulate the temperature effects at critical locations during the prefabrication phase. By varying the concrete mix proportions, initial casting temperature, and ambient temperature, the study elucidates the variation patterns of the temperature field during precast placement. The results show that the temperature rise caused by hydration heat increases with higher cement and fly ash content, whereas reducing cement and using minimal fly ash effectively lower the hydration temperature. However, the influence of fly ash on prestress losses should be carefully evaluated during the design phase. Higher initial casting temperatures accelerate hydration rates, leading to a rapid temperature rise. Significant differences between the initial casting and ambient temperatures result in larger residual temperature stresses. Based on concrete mix proportions, curing conditions, and ambient temperatures, three recommended casting temperature ranges were identified: 5°C–10°C, 10°C–25°C, and 25°C–30°C. Variations in the average ambient temperature affect the peak temperature of the hydration reaction and indirectly influence the final temperature distribution of the concrete structure. Optimizing the demolding time and applying geotextiles and water curing effectively reduces the peak temperature, maximum internal-to-surface temperature gradients, and surface tensile stresses, thereby mitigating the risk of temperature-induced cracking.
KW  - Corrugated steel web; composite box girder; finite element; temperature field; temperature stress

DO  - 10.32604/sdhm.2025.061554