Comparison of Structural Performance of a Multi-Story Reinforced Concrete Building and Its Equivalent Timber Building

An increased interest in decreasing the environmental impact of the construction sector and in vertical urbanization has renewed attention to timber as a primary structural material in multi-story buildings. This study investigated whether an existing 10-story reinforced concrete (RC) residential building can be redesigned as an equivalent mass-timber structure while satisfying the same structural performance requirements. It addressed the lack of like-for-like building-scale comparisons that redesigned an existing multi-story RC residential building into a functionally equivalent mass-timber scheme. A real RC building in Gävle, Sweden, was modeled, analyzed, and designed using StruSoft FEM-Design software in accordance with the Eurocodes and the Swedish National Annex, after which all main structural elements were systematically replaced with timber. Through iterative adjustments of member sizes, support conditions, and added reinforcing elements, both the RC and timber schemes were verified with respect to load-bearing capacity, serviceability, and global stability under identical load combinations. The RC and timber buildings reached maximum utilization ratios of 99% and 98%, respectively; displacements were higher in the timber building but remained within serviceability limits, and both systems were classified as globally stable. The timber alternative reduced the total structural weight to about 19% of the RC building and roughly halved the maximum vertical reaction forces, at the expense of additional beams, columns, and basement wall segments. Moreover, this article developed an equivalent-design methodology for material substitution, a bottom-up reinforcing elements logic that resolved serviceability and stability constraints in tall timber, and a performance trade-off map based on structural performance, offering guidance for future mass-timber design.