Seismic Performance of Timber–Steel Hybrid Structures. II: Calibration of Performance Objectives and Design Method

This paper presents the calibration of performance objectives and the development of a performance-based design method for timber-steel hybrid structures that consist of a steel moment-resisting frame and prefabricated infill light frame wood shear walls. Interstory drift was adopted as the indicator of structural or nonstructural damage. One hundred twenty single-story, single-bay timber-steel hybrid lateral load-resisting subassemblies with different configurations were modeled. The interstory drift limit for the immediate occupancy (IO) performance level was determined based on the numerical results from monotonic loading simulations, and the interstory drift limit for the collapse prevention (CP) performance level was obtained through incremental dynamic analysis (IDA). To consider the energy dissipation capability during earthquakes, semistatic cyclic analysis was conducted to study the hysteretic performance and damping effect of the timber-steel hybrid structures, and an expression is proposed to determine the equivalent viscous damping of such a structural system. A direct displacement-based design procedure was developed and a design example of a timber-steel hybrid structure was used to demonstrate the design procedure. This paper bridges the gap between a series of experimental and theoretical investigations and the engineering application of the innovative timber hybrid structural system.