摘  要：为了研究荷载与温度耦合作用下混凝土标准试件冻融试验中的预应力损失情况，以0.4fc、0.5fc、0.6fc三种应力水平的C30混凝土为研究对象，分析了加载过程中的预应力损失和快速冻融过程中的预应力变化。试验结果表明：实际预应力损失与理论计算值相差悬殊，加载过程中的预应力损失与试件的应力水平无关，占控制应力的15.4%～28%，平均值约为20%，大部分预应力损失发生在放张过程中。按1.25倍预应力设计值进行超张拉，基本可保证有效预应力与设计值的偏差在5%以内。在一个冻融循环过程中的预应力损失随着循环次数的增加而增加，75个循环后达到控制应力的7%～10%左右。

Abstract: In order to study the pre-stress loss of standard concrete specimens under the coupling of load and temperature in freezing and thawing experiment, C30 concrete specimens with three kinds of stress levels (0.4fc、0.5fc、0.6fc) are designed, and the prestress loss during loading and the change of prestress during the rapid freezing and thawing process are analyzed. The results show that there is a great difference between the actual prestress loss and the theoretical calculation value. The loss of prestress in the loading process is independent of the stress level of the specimen, and it accounts for 15.4%～28% of the controlled stress, with an average of about 20%. Most of the prestress losses occur during the enlargement process. It can guarantee the deviation of the effective prestress and the design value to be less than 5% when the super tension is carried out according to the 1.25 times prestress design value. In a freezing and thawing cycle, the loss of prestress increases with the increase of the number of cycles, and it reaches about 7%～10% of the control stress after 75 cycles.