Research Initiation: Effects of Sustained Load on the Performance of Reinforced Concrete Columns During Earthquakes

该项目的目标是：(2)确定柱纵向钢筋在持续轴向荷载作用下是否屈服，(3)确定柱的横向强度、刚度和变形能力的变化，(4)确定轴向荷载、持续轴向荷载的影响，(3)确定柱的横向强度、刚度和变形能力的变化，(4)定义轴向荷载、持续荷载周期和材料性能对柱侧向荷载响应的影响。在横向荷载试验之前，包含对梁-柱组件的实验室试样将经受持续的轴向荷载。一个计算机化的非线性模型将被开发来模拟柱的行为，包括材料特性的现实表现，横向加固的影响，和蠕变效应。这是一项研究启动奖，以开发一种计算方法来评估持续载荷对混凝土柱完整性的影响。使用该模型将允许用户定义旧混凝土柱的强度、刚度和变形极限。

The objectives of this project are: to quantify the stress-transfer process in concrete columns due to creep deformations, (2) to determine if column longitudinal reinforcement can yield under the action of sustained axial loads, (3) to identify changes in column lateral strength, stiffness, and deformability, and (4) to define the influence of axial load, sustained axial loads, (3) to identify changes in column lateral strength, stiffness, and deformability, and (4) to define the influence of axial load, sustained load period, and material properties on column response to lateral loads. Laboratory specimens, comprising pairs of beam-column subassemblages will be subjected to a sustained axial load prior to the lateral load tests. A computerized nonlinear model will be developed to simulate the behavior of the columns including realistic representation of material properties, effect of transverse reinforcement, and creep effects. This is a research initiation award to develop a computational method for assessing the effect of sustained loads on the integrity of concrete columns. Use of the model will allow the user to define the strength, stiffness, and deformation limits of old concrete columns.