预应力预制混凝土剪力墙截面设计方法

Design method of prestressed precast concrete shear walls

预应力预制混凝土剪力墙通过后张拉高强无黏结预应力筋将分段预制墙板拼装成整体,剪力墙与基础连接处布置若干普通钢筋以增强墙体的耗能能力。预制剪力墙在侧向荷载作用接缝处张开,依靠重力荷载和无黏结预应力筋提供恢复力。参照现行规范和已有的试验结果,给出了预应力预制剪力墙的性能目标,提出了预应力预制剪力墙截面设计方法,包括剪力墙截面尺寸、预应力筋、耗能钢筋以及墙脚约束混凝土设计。以4层预应力预制框架剪力墙结构为算例,采用有限元分析软件Open SEES建立数值分析模型,结果表明本设计方法可满足预期目标,进而验证了设计方法的合理性。

Prestressd precast concrete walls are constructed by utilizing high-strength unbonded prestressed tendons,with mild steel reinforcements across the base-to-foundation joint designed to yield in tension to increase energy dissipation ability. Lateral displacements result in a gap opening at the wall-foundation connection,and gravity loading and prestressed tendons provide the restoring force. The paper introduces performance levels for prestressed precast shear walls that conform to current codes and test results. Section design procedure of precast shear walls is provided,including geometry of shear wall section,post tensioned tendons,mild reinforcement and confined concrete design. A4-story design example demonstrating a step-by-step application of the design procedure is also presented. The design approach is critically evaluated based on nonlinear static analysis by using Open SEES software. It is shown that the designed structure satisfies the design prerequisites set forth.