Temperature Development Law and Crack Prevention and Control of Mass Concrete of Raft Foundation
Based on the mass concrete construction of a raft foundation in Xi'an,the temperature development law of mass concrete of raft foundation is obtained through on-site monitoring.The influence of fly ash content,layered pouring thickness and molding temperature on the temperature development law of mass concrete is analyzed by numerical simulation.Finally,the crack prevention and control measures caused by the temperature rise of mass concrete are summarized.The results show that the concrete temperature of the temperature of concrete in the center of raft foundation reaches the peak at about 50h,and the surface concrete temperature reaches the peak at about 70h.When the concrete strength and the total content of cementitious materials are constant,the peak temperature of raft foundation decreases with the increase of fly ash content,the decrease of raft layered pouring thickness and molding temperature.The structural cracking caused by the temperature rise of mass concrete can be reduced by selecting silicate cement with low hydration heat,increasing the content of fly ash,adding an appropriate amount of expansion agent,reducing the molding temperature,watering curing,temperature monitoring and other methods.The construction can be adjusted according to the construction conditions.
万方数据
维普
