<title>Optimal NiTi hybrid tendon system for structural vibration control</title>

Abstract

Recent developments in the new field of auto-adaptive materials offer promising opportunities for developing radically new fastening mechanisms. One of the classes of materials in this category is Shape Memory Alloys (SMAs). SMAs are very attractive for structural application because of their major constitutive behaviors such as pseudoelastic characteristic. Pseudoelastic behavior of NiTi SMAs is a unique hysteretic energy dissipation behavior that combined with a very long fatigue life makes SMAs a viable candidate for developing new fasteners. Pseudoelastic behavior of Shape Memory Alloys, particularly NiTI, can be used for developing passive fastening-mechanisms and tendon-systems. In case of coastal structures, where hurricane destruction inflicted upon residential structures results in million of dollar in financial damages and loss of lives each year, development of more effective fastening-mechanisms and tendon-systems for the connections between the walls and the roofs will aid in damage reduction. A study carried out by the authors has shown that the extent of damping effect of a hybrid tendon-system, made of rigid NiTi sections directly depends on the length-ratio of the rigid NiTi section, tendon diameter and the amount of pre-strain on the tendon. Moreover, because of tendon-system passive design the nature of excitation has a profound effect on its activation and damping capability. In this paper effectiveness of a hybrid NiTi tendon-system for damage mitigation of coastal structures and optimal hybrid tendon length-ratio are studied.