Seismic performance of energy-dissipating post-tensioned CLT shear wall structures II: Dynamic analysis and dissipater comparison

Abstract

The work described herein was conducted within the performance-based seismic assessment framework on both post-tensioned (PT) CLT shear wall structures with UFP dissipaters (PT-Strs-U) or with friction dissipaters (PT-Strs-F). In this paper (Part II of the work), a more extensive study was conducted for the PT-Strs-U and PT-Strs-F, dealing with structural design method, structural modeling, seismic performance assessment, and post-earthquake loss assessment. In the previous study (Part I of the work), both the design capacities of the PT CLT shear walls and the corresponding parameters of the incorporated dissipaters were provided. Using these data, a direct displacement-based design (DDD) procedure was applied for designing both one 8-storey PT-Str-U and one 8-storey PT-Str-F. A simplified structural model was also developed in OpenSees for both structures. Pushover and time-history dynamic analysis were conducted to calibrate the calculated structural performance objectives within the design targets of the DDD procedure. Finally, based on the calibrated structural models, seismic performance of the PT-Str-U and of the PT-Str-F was assessed using the fragility curves. The post-earthquake loss assessment was also conducted afterwards in terms of the inter-storey drift, absolute floor acceleration, and shear deformation of the dissipaters. Overall, the maximum inter-storey drift of the PT-Str-U is similar to that of the PT-Str-F under the earthquakes. In most cases, the friction dissipaters perform better than the UFP dissipaters for mitigating the absolute response accelerations of the structures. When taking the total post-earthquake loss of the structures into account, the friction dissipaters are recommended, which can result in a less post-earthquake loss for the energy-dissipating PT CLT shear wall structure, compared to the UFP dissipaters.