Cu SMA Reinforced ECC Plastic Hinge - Reassembled Column Test (CE-R)

Column model quarter scale precast plastic hinge using conventional reinforced concrete in the footing and top column body, and tensile-resilient ECC (Engineered Cementitious Composite) and unbonded CuAlMn superelastic SMA (Shape Memory Alloy) in the plastic hinge base element. Column dimensions and reinforcement followed the 2011 AASHTO Guide Specifications for LRFD Seismic Bridge design when possible. The base element's longitudinal and transverse steel were proportioned to be around typical values used for reinforced concrete bridge columns. The confinement and reinforcement in the upper column body were proportioned to avoid damage in this element. The 228 component of the Rinaldi Receiving Station (RRS) record of the Northridge Earthquake was used for shake table tests. The design ground motion was determined based on the 5%-damped spectral ordinate for a period equal to the effective period. Time scale has been compressed by a factor of 0.5 to account for the geometric scale of the column model. Column geometry: 63.5 inch height, 12 inch column diameter at base, 4.5 aspect ratio, 60 kip axial load, axial load index 12.3%, 1.46% longitudinal SMA reinforcement ratio, 2.69% transverse steel ratio. Mass rig frame & blocks together equal 60 kip inertia mass.

本柱体模型为1/4缩尺预制塑性铰试件，基础与柱身上段采用常规钢筋混凝土制作，塑性铰基座单元则采用抗拉韧性工程水泥基复合材料（Engineered Cementitious Composite）与无粘结铜铝锰超弹性形状记忆合金（Shape Memory Alloy）。柱体尺寸与配筋设计尽可能遵循2011年美国公路与运输官员协会（AASHTO）发布的《荷载抗力系数法桥梁抗震设计指南》。基座单元的纵向与横向配筋比例参照钢筋混凝土桥梁柱的常规配筋参数确定。柱身上段的约束构造与配筋设计旨在避免该区域发生损伤。试验采用北岭地震中里纳利接收站（Rinaldi Receiving Station）记录的第228号地震动分量作为振动台试验输入。设计地震动根据与模型有效周期对应的5%阻尼比谱加速度幅值确定。考虑柱体模型的几何缩尺效应，试验时将地震动时间轴压缩为原长的0.5倍。柱体几何参数如下：总高度63.5英寸，基座处柱径12英寸，长细比4.5，轴向荷载60千磅力（kip），轴压比12.3%，纵向超弹性形状记忆合金配筋率1.46%，横向配筋率2.69%。配重架与配重块总惯性质量为60千磅力。