1 INTRODUCTION Current seismic design philosophies for multi- storey buildings emphasize the importance of de- signing ductile structural systems which undergo cy- cles of inelastic displacement during earthquakes, resulting in some residual damage but no significant reduction in strength. Ductile design recognizes the economic disadvantages of using elastic design of buildings to withstand earthquakes with no structural damage. This particularly applies to multi-storey buildings in moderate or high seismic regions. In or- der to reduce residual damage in ductile buildings, revolutionary solutions have been developed under the U.S. PRESSS (PREcast Structural Seismic Sys- tems) programme coordinated by the University of California, San Diego (Priestley et al. 1999) for the seismic design of multi-storey precast concrete buildings. Such solutions, also applied to steel con- struction (Christopolous et al. 2001), are based on “dry” joints between pre-fabricated elements and unbonded post-tensioning techniques. As a result, extremely efficient structural systems are obtained, which can undergo large inelastic displacements similar to their traditional counterparts (monolithic connections), while limiting the damage to the struc- tural system and assuring full re-centring capability after the seismic event. A particularly efficient solu- tion is provided by the “hybrid” system (Fig. 1a) where an appropriate combination of self-centring capacity (unbonded tendons plus axial load) and en- ergy dissipation (mild steel dissipation devices) leads to a sort of “controlled rocking motion”, char- acterized by a peculiar “flag-shaped” hysteresis loop (Fig. 1b). This paper investigates the use of these in- novative solutions for multi-storey timber buildings with seismic moment-resisting frames and jointed ductile connections. If the self-centring ductile sys- tem is to be adopted for timber buildings, Laminated Veneer Lumber (LVL) has important advantages compared to glue laminated and sawn timber, espe- cially the randomization of wood defects and quality control during manufacture which lead to a nearly homogenous material with low variability of me- chanical properties. This paper presents preliminary experimental results for hybrid exterior beam-to- column and column-to-foundation subassemblies under cyclic quasi-static unidirectional loading. Two Quasi-static cyclic tests on seismic-resistant beam-to-column and column-to-foundation subassemblies using Laminated Veneer Lumber (LVL) A. Palermo Department of Structural Engineering, Politecnico di Milano, Italy S. Pampanin, M. Fragiacomo, A. Buchanan, B. Deam, L. Pasticier Department of Civil Engineering, University of Canterbury, New Zealand ABSTRACT: This paper describes part of an extensive experimental programme in progress at the University of Canterbury to develop Laminated Veneer Lumber (LVL) structural systems and connections for multi- storey timber buildings in earthquake-prone areas. The higher mechanical properties of LVL, when compared to sawn timber, in addition to its low mass, flexibility of design and rapidity of construction, create the poten- tial for increased use of LVL in multi-storey buildings. The development of these innovative ductile connec- tions in LVL, proposed here for frame systems, have been based on the successful implementation of jointed ductile connections for precast concrete systems, started in the early 1990s with the PRESSS Program at the University of California, San Diego, further developed in Italy and currently under further refinement at the University of Canterbury. This paper investigates the seismic behaviour of the so-called “hybrid” connection, characterised by the combination of unbonded post-tensioned tendons and either external or internal energy dissipaters passing through the critical contact surface between the structural elements. Experimental results on hybrid exterior beam-to-column and column-to-foundation subassemblies under cyclic quasi-static unidi- rectional loading are presented. The proposed innovative solutions exhibit a very satisfactory seismic per- formance characterised by an appreciable energy dissipation capacity (provided by the dissipaters) combined with self-centring properties (provided by the unbonded tendons) and negligible damage of the LVL structural elements.