Application of an iron-based shape memory alloy for post-tensioning glass elements

Abstract Previous research has evidenced that by adding a ductile reinforcement on the tension side of glass beam, for instance adhesive bonding, its post-cracking behaviour and redundancy were improved, while an additional pre-stressing this further helped to increase initial cracking resistance. Past investigations used steel tendons or stainless strips, which required rather complex setups procedures mechanical pre-stressing. This study aims introduce easier-to-apply procedure with strips made iron-based shape memory alloy (Fe-SMA), property remembering after phase transformation from austenite martensite. The Fe-SMA can be anchored parent structure as pre-strained in case substrate bonding. After activation through heating cooling process, tensile stress is generated strip, applies compressive field into structure. work discusses results first feasibility dealing choice identifying suitable adhesively bonded elements. effective bond length, needs considered when defining anchorage was determined two structural adhesives. While high-strength, brittle 2c-epoxy SikaPower®-1277, shorter lengths little more than 120 mm sufficient, 2c-methacrylate Araldite® 2047-1, longer necessary same load level (more 240 mm). Furthermore, electrical resistive applied, (i) allowed sufficient activation, (ii) avoided too high instant temperature changes (iii) did not affect length.