Effect of Base Temperature on Early Stress Strength Ratio for Concrete Pavement

In order to explore the effect of base temperature on early cracking of concrete pavement slabs, the concrete surface was paved on six kinds of bases whose temperature was 10, 15, 20, 25, 30, and 35°C, and the stress strength ratio of concrete slabs within 72 h after paving were calculated and the risks of cracking were also compared. The results show that: The higher the base temperature, the earlier the structural stress occurs. In order to reduce the risk of slab cracking, the concrete surface should be paved when the base temperature is low; within 48 h after concrete pouring, the maximum principal stress growth rate caused by the high base temperature is much greater than the tensile strength. During this period, the concrete strength is still low, the stress develops rapidly, and the pavement structure is exposed to the risk of cracking at any time. It is necessary to pay attention to the external health curing during this period to reduce the high cracking risk faced by the slab; at the final setting time, the base temperature is the main reason for the difference of the stress strength ratio. After that, the ambient temperature gradually replaces the base temperature and becomes the dominant factor. Therefore, for the crack caused by the base temperature, the control measures should be applied before the final setting time, and the countermeasures for the cracking of the slab after the final set should be mainly designed for the superposition effect of the ambient temperature and the hydration heat.