持荷混凝土构件耐久性试验加载装置应用技术

Applied Technology of Loading Equipment for Durability Testing of Holding Charge Concrete Component

针对混凝土构件耐久性试验环境的腐蚀性和多变性、试验设备容量的限制、混凝土的徐变及加载杆件的松弛等影响,对持荷试件加载装置进行了设计与研究。通过自平衡加载装置对紧固件施加扭矩来控制持荷试件的应力水平,并实时监测不同材质及环境下的扭矩系数、混凝土徐变和紧固件的应力松弛,以此获得扭矩的衰减规律,为试件应力补偿提供理论依据。采用两套加载装置对8根(套)试件进行了测试,试验结果表明,自平衡加载装置适用性强、加载及其补偿简便且能够满足试验要求,持荷试件应力损失在六周后趋于稳定。该装置及其应用技术可用于荷载与环境共同作用下混凝土构件的耐久性试验。

Loading device for holding charge specimen was designed and studied, aiming at the effect of corrosiveness and variability of experimental environment for concrete component durability test, of laboratory equipment capacity restriction, of concrete creep and relaxation of loaded rods. In order to obtain torque attenuation pattern and provide theoretical basis for specimen stress compensation, the stress level of holding charge specimen was controlled through applying torque to the fastener by self- balanced loading device, and the torque coefficient, the concrete creep and the fastener stress relaxation of different materials and in different environments were monitored in real-time. Testing was carried out hy using two sets of loading apparatus and eight specimens. Experimental results show that the self-balanced loading device is applicable, loading and compensation are easy and meet experimental requirements, stress loss of holding charge specimen is stabilized after six weeks, which proves that this device and its applied technology can perfectly satisfy the requirements of concrete component durability test, especially under the action of both loading and environment.