Buildings constructed from engineered timber are becoming more prevalent globally as building designers, owners and architects realize the sustainability opportunities with timber construction and the overall aesthetic of a completed timber building. As timber buildings are planned to be taller than many model codes permit, the National Fire Protection Association (NFPA) Fire Protection Foundation commissioned research entitled "Fire Safety Challenges of Tall Wood Buildings", with the aim of understanding where the current gaps in knowledge are and how the research agenda should be prioritized. With new engineered timber products such as cross-laminated timber becoming more prevalent, this study evaluated the current knowledge of tall timber construction to identify gaps in knowledge, and where if fulfilled, will provide a better understanding of the potential fire safety performance of tall timber buildings. The study identified a number of knowledge gaps, of which most were related directly to the new technology of engineered timber products that have resulted from the use of CLT. These included system-level fire testing, use of composite assemblies, CLT char fall-off and construction fire safety. The study concluded that the priority for future research should target three areas of research, being the contribution of exposed timber to room fires; connections between timber components and timber composite assemblies; and penetrations for building services.

An analysis of the dynamic response of bridge piers to measured ice loads is presented. The dynamic structural properties of piers and piles are described and the idealization of these structures for purposes of analysis is discussed. The characteristics of ice force histories recorded at a bridge pier in a large river in central Alberta are illustrated and the dynamic response of bridge piers to typical ice force events is determined. The results of this analysis are presented in the form of response spectra, which enable a rapid appraisal of the magnification, or reduction, in response that can result from dynamic effects. The analysis confirms that bridge piers, including massive ones, will fully respond to peak ice forces. Furthermore it shows that, depending on the natural frequency and damping of the pier and foundation, the dynamic response can exceed the static response to the peak ice force.

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