Seismic mechanism analysis of a traditional Chinese timber structure based on quasi-static tests

In this paper, a single-layer 1:2-scaled specimen of a timber building was fabricated according to the construction method of the Chinese Song Dynasty, and six quasi-static tests were conducted under three levels of vertical loads to investigate the associated seismic mechanism. The results in this study indicate that the vertical uplift of the timber structure caused by rocking under lateral loading is nonnegligible. During the quasi-static tests, a portion of the energy input to the timber structure, namely, the hysteretic energy, is dissipated through plastic and friction energy dissipation. The remaining energy is converted into gravitational potential energy (GPE) and elastic strain energy (ESE) through the uplift of the timber structure and the elastic deformation of wood components and stored in the timber structure. The hysteretic energy and ESE account for the majority of the input energy when the cyclic amplitude is small. The majority of the input energy is converted into GPE at large cyclic amplitudes. The storage and release of energy is the main mechanism that allows this type of traditional timber structure to resist earthquake actions. Moreover, the influences of the vertical load and loading time were studied.