Bracing System Development for a CLT-Residential Building Under Seismic Loading. Comparison of Results From a Climate Performance and Life Cycle Point of View

Abstract

Research on the performance of a structure built from cross-laminated timber (further referred to as CLT or X-LAM) panels under seismic loading with different types of stiffening systems was conducted in this thesis. To begin with, the research considered the behaviour of an existing structure constructed from CLT panels under seismic loading. Based on the quantitative results of the analysis, conclusions about the strength and geometrical imperfection of the original structure were outlined. As the load bearing capacity of the frame had been proved to be insufficient, three different stiffening options for it were considered next. Consequently, the essential part of the thesis was devoted to the study of the behaviour of the structure, with different stiffening systems that rely on using concrete, steel and thicker CLT-wall elements. Another important aspect of the research was to compare the above-mentioned results from the point of climate performance and life cycle. To this end, each stiffening option was evaluated in terms of carbon dioxide emissions, and the results were compared. Hence, the work also contributed to the field of identifying the most efficient types of stiffening system from the point of view of carbon-dioxide footprint. The structural calculation was performed according to EN 1998-1: Eurocode 8 (EC8) and EN 1991-1: Eurocode 1 (EC1). To carry out a life cycle analysis (LCA), the One Click LCA sustainability platform was used. The results of the research indicated that adopting massive cross-laminated (X-LAM) timber panels is a feasible solution for high-performing building constructions in earthquake-prone zones. In such cases, selecting the appropriate stiffening system requires careful consideration of its dependencies on the architectural concept and life cycle assessment factors. Furthermore, additional studies are necessary, particularly regarding the structural design of connections and the development of damper technologies.