2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Cristiano Loss
Dr. Asif Iqbal, University of Northern British Columbia (Presenter)
Mr. Thomas Tannert
Sustainable construction methods are becoming a priority topic in the 21st century to reduce the environmental footprint of the building industry. Hybrid systems, which combine wood with other non-combustible materials, can enable application of engineered wood products beyond low- and mid-rise construction. This paper presents structural and environmental analyses on a novel tall wood-concrete hybrid system, where a concrete frame consisting of slabs at every third story provides fire separation as well as the necessary stiffness and strength to resist gravity and lateral loads. The intermediate stories including their floors are constructed using wood modules to create the usable space. This innovative approach reduces the environmental footprint of the building, reduces the building weight and therefore the seismic demand on connections and foundation, and speeds up the construction process. To study this hybrid concept, a 30-storey case-study building with regular floor plan was designed and compared to a regular all-concrete building. The gravity and lateral loads were analyzed for a building location of Vancouver, BC according to the 2015 National Building Code of Canada using ETABS. The results showed that the lighter hybrid option allows the use of a smaller concrete cores to resist the lateral loads. While inter-storey drift code requirements are met, wind becomes the governing lateral load case over seismic load demands due to the reduction of building mass. In addition to the structural design, a life cycle assessment was performed using the Athena Impact Estimator for Buildings. The hybrid building is significantly superior by reducing the amount of concrete by almost 60% which leads to lower environmental impacts in multiple categories. The research demonstrates the feasibility of the proposed hybrid system for tall buildings in high seismic zones.