【摘要】 外掺MgO混凝土由于自生体积变形具有良好的延迟性微膨胀而被成功应用于多个水利水电工程。结合工程实践,根据筑坝实际温度场的特点,研究了20℃、30℃、40℃及50℃4种恒定养护温度下,外掺3.5%、4.5%和5.5%MgO混凝土的自生体积变形试验,获得了不同养护温度及不同MgO掺量的自生体积膨胀变形曲线。研究结果表明,外掺MgO混凝土具有明显的温度效应,各温度下的自生体积变形曲线变化规律基本一致,均随养护温度的提高而增大;同时外掺MgO混凝土具有良好的延迟微膨胀性能,其自生体积变形随龄期增长而增加并趋于稳定,也随MgO掺量增加而增加。这些研究成果为后续的工程仿真计算分析提供了科学的试验参数。更多还原

【Abstract】 Based on engineering practice,an experimental research is done on autogenous deformation of concrete mixed with MgO at four curing temperatures of 20℃,30℃,40℃,50℃ and three MgO mixing amount of 3.5%,4.5%and 5.5%.The study obtains the autogenous volume deformation curves at different curing temperatures and mixing amount of MgO.The results indicate that the concrete mixed with MgO has obvious temperature effect and good delayed expansive properties.There are consistent change laws of autogenous deformation curves at different curing temperatures.The autogenous deformation of concrete is proportional to curing temperature,experimental age and mixing amount.The research results provided scientific experimental parameters for simulating calculation and analyses of subsequent projects.更多还原