论文部分内容阅读
环向钢筋预应力损失是采用内埋式应变计来测量钢筋应力后才发现的。本文采用P-T-e数据模型及热应变转换应力的原理对此损失作了探讨。混凝土在蒸养中初期因升温而逐渐凝固,E和λ均非常量,随凝固逐渐达到稳定值。钢筋因升温而膨胀,在混凝土的凝固过程中,此膨胀受到约束而转换成应力。此应力恰和已施加的预应力方向相反而抵消,故产生损失。弹性损失纯属机械性质,未作探讨。
The pre-stress loss of the hoop steel was only found after the stress of the steel bar was measured by the embedded strain gage. This paper discusses this loss using the P-T-e data model and the principle of thermal strain transfer stress. In the initial stage of steam curing, the concrete gradually solidifies due to the increase in temperature. Both E and λ are extremely large, and gradually reach a stable value with solidification. The steel bar expands due to warming. During the solidification of the concrete, this expansion is constrained and converted into stress. This stress just cancels out in the opposite direction of the applied pre-stress, and therefore it is lost. Elastic loss is purely mechanical and has not been discussed.