Early Cracking Risk Prediction Model of Concrete under the Action of Multifield Coupling

Abstract

Through the adiabatic temperature rise experiment, the adiabatic temperature rise of concrete with hydration time was recorded. Based on the maturity degree theory, the relationship between the hydration degree of the concrete and the equivalent age was determined. Then, the hydration degree prediction model of the concrete's early elastic modulus and tensile strength was established. The local temperature and humidity of the concrete were measured by the shrinkage experiment, and based on the capillary water tension theory, a temperature-humidity prediction model for the early shrinkage of the concrete was designed. According to the ratio of the creep deformation and elastic deformation of concrete which were obtained through the restraint ring experiment, a model for predicting the early creep coefficient of concrete was proposed. Based on the coupling effect of “hydration-temperature-humidity,” a prediction model of early cracking risk coefficient of concrete under multifield coupling was proposed. Finally, several groups of slab cracking frame experiments were carried out, and the cracking risk prediction results of concrete were consistent with the actual situation, which indicated the correctness of the early cracking risk prediction model of concrete.

Experimental Study on Macro-performance of Long-age Hydraulic Concrete Based on High Temperature Accelerated Curing

“…Equivalent age is frequently used to describe the temperature and age in the cement hydration process on the adiabatic temperature rise, strength and modulus of elasticity and other thermal and mechanical properties (Jin et al 2021). It refers to the concrete with same mix ratio in different temperature-time courses to achieve the same degree of hydration and the need to curing time at the reference temperature (20°C).…”