Development and experimental validation of anchorage systems for shape memory alloy cables

Abstract

In this paper, two types of mechanical anchorage systems for shape memory alloy (SMA) cables are developed and their performance and feasibility are experimentally evaluated under various loading conditions. First, the detailed descriptions of two anchorage systems and the installation of SMA cables into the anchorage systems are described. Then, the proposed anchorage systems are designed and fabricated for an SMA cable with a diameter of 8 mm and 7 × 7 configuration. SMA cable specimens are prepared with two different anchorage systems for experimental characterization. The specimens are subjected to tensile loading-unloading cycles at various strain amplitudes and frequencies. A low-cycle fatigue test is also conducted. Then, the specimens are loaded in increasing strain amplitudes up to failure. Various mechanical properties such as maximum stress, residual strain, hysteretic energy, and equivalent viscous damping ratio are computed and analyzed for SMA cable specimens with different anchorage systems. Failure mechanisms of the specimens are also evaluated through scanning electron microscopy images. Results suggest that a mechanical anchorage system with an end stop can successfully anchor SMA cables in seismic applications.