Bulletin of Earthquake Engineering, cilt.18, sa.10, ss.4985-5008, 2020 (SCI-Expanded)
This paper describes the full-scale test program of a code-conforming Post and Beam shearwall system conducted in a curtain wall test facility. The two-story test specimen is taken from a slice of index full-scale test structure to represent the first-mode dominant response properties. The design of the full-scale index building was carried out following the code requirements of wood buildings classified equal to or higher than the Grade-2 index buildings regarding the seismic grading scheme. The test program was not only aimed to provide an in-depth understanding of the seismic response characteristics of the shear wall assembly under cyclic deterioration but also contributed to developing reliable numerical models during the preliminary design phase of the 2019 full-scale shake table test program of the Tokyo Metropolitan Earthquake Resiliency Project. Moreover, the effectiveness of the instrumentation scheme to trace the distinct damage states and identification of the failure mechanism was examined using the advantages of full-scale testing. A novel cyclic loading test protocol was systematically applied to the shearwall assembly to capture the progressive damage starting from the initiation of elastic deformations to the near-collapse limit state. Shearwall assembly was tested until reaching the 1/21 rad interstory drift angle to determine the failure criterion of the shear wall assembly. Applied test procedure using a curtain wall test rig is useful and cost-effective for testing two different forms of systems to establish the damage pattern and deterioration characteristics of structural systems rather than only performing conventional tests for a particular structural system. At the end of the test sequence, gypsum wallboards were fallen apart due to the detachment of nails and out-of-plane buckling failure of diagonally brace. A numerical model incorporating negative stiffness branch in the backbone curve and all significant modes of cyclic deterioration of the P&B shearwall assembly is generated based on the energy-based hysteretic model. The generated numerical model and the test results were found compatible as a result of sensitivity analyses.