Pilot study of a high capacity ductile seismic holdown for cross laminated timber

Abstract

New manufactured wood products referred to as mass timber have allowed for greater seismic load capacities than ever before for designing wood structures. The increased capacities could allow for taller wood structures; however, traditional wood connections do not meet the seismic performance needs for new manufactured wood products such as cross laminated timber (CLT). New connection methods must be investigated to allow for the growth of the CLT industry in mid- and high-rise structures. The objective of this research is to develop a wood connection to resist larger uplift forces experienced in CLT structures and provide energy dissipation in seismic events. The connection development was performed through fastener testing using self-drilling dowel fasteners for concealed connections with steel knife plates installed in a wood member. Finite element modeling and testing of reduced section steel plate to provide a ductile response to cyclic loading was performed to determine the feasibility of this connections style. The results of the investigation indicate that reduced section steel plates that limit the connection failure to a desired location in the steel plate could greatly increase the seismic performance of CLT seismic force resisting systems.