缓粘结预应力钢筋摩擦系数试验

为了探明张拉时缓粘结剂固化程度对预应力钢筋摩擦损失的影响规律,制作6根预应力梁,每根梁直线布置3根缓粘结预应力钢筋,进行张拉试验.按照缓粘结剂的固化程度,对预应力钢筋分批进行张拉,并测得钢筋应力的摩擦损失.结果表明,在缓粘结剂固化程度相同的条件下,随着张拉力的增加,缓粘结剂的粘结作用失效,钢筋应力的摩擦损失逐渐变小;预应力钢筋达到控制应力时,随着缓粘结剂硬度的增加,粘结作用增强,摩擦损失增大;当缓粘结剂邵氏硬度达到80以上时,摩擦系数k达到了0.538 m~(-1).

Experiment on friction coefficient of retard bonded pre stressed tendon

In order to clarify the influence of the curing degree of retard bonded adhesive on the friction loss of pre stressed tendon in the tensile process, six pre stressed concrete beams, each of which was arranged with three straight pre stressed retard bonded tendons, were prepared to perform the tensile experiments. According to the curing degree of retard bonded adhesive, the pre stressed tendons were tensioned in batches, and the friction loss of tendon stress was measured. The results show that when the curing degree of retard bonded adhesive is the same, the adhesive effect of the adhesive fails and the friction loss of tendon stress gradually decreases with increasing the tensile force. When the stress applied on the tendons reaches the control stress, the adhesive effect gets enhanced and the friction loss increases with increasing the hardness of retard bonded adhesive. When the Shore hardness of adhesive is more than 80, the friction coefficient k reaches 0.538m^-1