Debonding : A Study in Chance - Dr Richard Emberley

Abstract: In order for timber to be used as a structural material, the flaming combustion of timber has to cease after burnout of the fuel within the compartment. The phenomena of self-extinction, whereby timber cannot sustain a flame without an external energy source, is a fundamental concept which underpins the entire fire safety design of timber. One of the main hindrances preventing self-extinction in engineered timber is debonding of the lamella of the timber cross section through the interaction of thermal and mechanical stresses coupled with strength and material degradation of the adhesive. These factors precipitate char and solid timber fall-off of timber members which can cause increased charring rates, increased burning durations, potential secondary flashover events, and decreases in structural integrity beyond just loss of cross section due to charring rate. The seminar will discuss previous, current, and potential plans for future research into debonding and the mechanics of debonding. Highlighted topics to include areas of concern regarding the current apparent unpredictability of debonding; difficulties in measurement of timber and adhesive properties; a lack of agreement on mechanics, potential solutions, and adhesives; and as well a path ahead for systematic study into debonding and adhesive behavior.

Bio: Richard Emberley is currently an assistant professor in the Mechanical Engineering Department and Fire Protection Engineering Program at California Polytechnic State University (Cal Poly). Richard recently completely his PhD under the supervision of Professor Jose L. Torero at the University of Queensland in Brisbane, Australia. Richard holds two MS degrees in Civil and Fire Protection Engineering from Worcester Polytechnic Institute as well as a BS in Civil Engineering with a focus on Structural Engineering. His research focuses in the areas of fire safety engineering, structural mechanics, combustion, and heat transfer. His PhD research focused on structural debonding of cross laminated timber under fire conditions as well as self-extinction of timber and the fundamentals for designing tall timber buildings for fire exposure. Richard is currently visiting The University of Edinburgh for two weeks as part of the IMSFE Guest Scholar Program.