Based on the microstructure of cement paste, several kinds of creep mechanisms of concrete were studied. It was put forward that the creep was aroused by the motion of the internal water in the concrete and the moisture exchange with the external environment under sustained load. By use of the foreign scholar s' experimental data, a creep model for concrete based on the equivalent time was established. The influences of different curing temperatures (20℃, 40℃,65℃ ) on the concrete creep were investigated. The results show that the rise in ambient temperature accelerates the hydration rate of cement and the evaporation rate of water, consequently, the development of early-age strength of eoncrete increases and its shrinkage decreases, so concrete creep decreases. The temperature rise reduces the viscosity of water and thus raises the concrete creep. The creep of concrete in high temperature ( ＜ 70℃ ) increases with the increase of temperature.%基于水泥浆的微观结构,研究了混凝土徐变发生的几种机理,指出徐变是由于荷载作用下混凝土内部水的运动以及与外界发生水交换而引起的.采用国外学者的试验数据,提出了基于等效时间的混凝土徐变模型,研究了不同养护温度(20℃,40℃,65℃)对混凝土徐变的影响.研究结果表明,环境温度升高加快了水泥的水化反应速率和水分的蒸发速率,混凝土的早期强度发展加快,收缩减小,因而徐变减少;温度升高降低了水泥浆中水的黏滞性,增加了混凝土的徐变;高温环境中(<70℃)混凝土的徐变将随温度的升高而增大.
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