Numerical and Experimental Analysis of Composite Sandwich Links for the LCF System

• Main Author: Stephens, Max Taylor
• Format: Others
• Published: PDXScholar 2011
• Subjects: Linked column frame system; Sandwich plate; Shear link; Shear (Mechanics); Buckling (Mechanics); Plates (Engineering); Structural stability > Mathematical models
• Online Access: https://pdxscholar.library.pdx.edu/open_access_etds/579; https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1578&context=open_access_etds

Shear links are used as fuse elements in lateral load resisting systems to provide ductility and dissipate seismic energy. These links have traditionally been employed in eccentrically braced frames, but have more recently been suggested for use in the innovative linked column frame system (LCF). Current design specifications for shear links require intermediate web stiffeners to provide out-of-plane web stability so ductility requirements can be achieved. This research focused on moving from discrete transverse web stiffening to continuously stiffened webs in built up shear links. Built up links were designed to yield in shear when subjected to severe cyclic loading, however the webs of the links were designed using two metal sheets joined by an elastic core. These composite "sandwich" webs allowed for an increase in web thickness (and inherent flexural rigidity) without increasing the shear strength of the links. Numerical and experimental investigations were conducted to assess the performance of composite sandwich links subjected to severe loading. Numerical results showed improved web behavior in sandwich links in which the core material was assigned an elastic modulus greater than 5000psi. Due to fabrication limitations, experimental specimens were fabricated with a core material elastic modulus of 1000psi. These specimens did not perform as well as unstiffened base case links in terms global hysteretic behavior or ductility.