SUMMARYA series of dynamic experiments was performed on two-story glue-laminated timber frames. The tests included sinusoidal sweeps in one direction, arbitrary signals simulating earthquake loads in two directions, and harmonic free vibration at the fundamental frequency. Two experimental frames were manufactured and tested: (1) a control with horizontal laminations and no reinforcement at joint areas, and (2) a new frame design with densiÿed material in the joint area that was further reinforced by glassÿber composite material. Preliminary tests of scaled and full-size beam-to-column connections were performed to obtain connection characteristics needed for subsequent analytical modeling.

This paper describes the analytical models of timber connections that were used to simulate the full time‐history response of moment‐resisting frames subjected to dynamic loads. Special attention was paid to connection modeling to capture the hysteretic damping that significantly affected the performance of the system subjected to dynamic forces. To model the hysteretic properties of the dowel‐type connections a combination of bilinear springs and gaps was used. This approach allows the modeling of various hysteretic shapes including pinching, asymmetric behavior, contact phenomena, and an initial slip of the fasteners. Load–deformation curves obtained from the cyclic experiments of small‐ and full‐scale joints were used to extract the model parameters. The hysteretic models were verified by comparing the simulation with the experimental data obtained from cyclic tests. The comparison reveals that the presented approach can be successfully used to simulate the load‐history‐dependent behavior of timber joints, provided that strength degradation is negligible and a brittle failure does not occur. The predictive ability of a 3D frame model will be demonstrated in Part II by comparing the simulation with the results of shake table experiments.

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Laminated timber frames behave well under dynamic earthquake loads, but the beam-tocolumn connections may be susceptible to a brittle-type failure, due to tensile stresses across wood fibres. Fibre-based materials such as nonwoven glass-fibre fabric are effective in mitigating the tensile failures and increasing the ductility of the connections. While global performance of such connections and frames shows satisfactory results, some fundamental questions associated with the performance of the composite-wood system and interface in aggressive environments, under elevated temperatures and long-term loading, must be answered before the composite systems can be safely used in engineering practice.

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