CONSTRUCTION INNOVATION, Sept. 2009

[ Table of contents | Subscribe ]

Providing a better understanding of thermal expansion in reinforced concrete structures under fire exposure is the focus of a new four-year study by NRC-IRC's Fire Research program. Thermal expansion is defined as the tendency of structural elements to change in volume (size) as the result of change in temperature. In fire, high temperatures cause building elements such as floors, beams and columns to expand significantly which, in turn, may cause stress and potential failure of supporting columns. 

An NRC-IRC full-scale column furnace test facility will be used to research the effect of thermal expansion on reinforced concrete building columns.

Thermal expansion has been reported as an initial cause of structural failure in several mid- to high-rise buildings. It is believed that thermal expansion has an important effect on concrete structures, depending on the size of the elements and their restraint conditions.

This research project will develop assessment and design tools for improving fire protection and safety in reinforced concrete buildings including residential, hotel, hospital and care facilities as well as offices. The project aims to answer questions such as:

• How significant are the effects of thermal expansion on building performance and safety?
• How does one simulate performance of structures in fire, considering thermal expansion?
• What types of building damage or failure are caused by thermal expansion?
• How does one improve safety and design in reinforced concrete buildings with regard to the effects of thermal expansion?

A new testing technique will be used to focus on the effects of floor thermal expansion and how it relates to the performance of reinforced concrete columns - elements that play a major role in the stability of an entire structural system. The results will be applied to concrete columns using the NRC-IRC full-scale column furnace test facility.  Analysis will be conducted in collaboration with the University of Toronto.

Although this research is being conducted for building columns, the findings could be applied to other structures such as bridge columns.

Seeking Collaborators

NRC-IRC is seeking industry and regulatory collaborators for the study. Participants will have the opportunity to comment on the project's scope, designs and documents as well as to assist with technology transfer to regulatory bodies and the construction industry. They will receive both preliminary results and a final report containing the technical basis of the study, experimental methods, and an evaluation of results. A results database including the characteristic and performance profiles and temperature will be accessible, forming the basis of a modelling tool that may be used to generate both appropriate designs and guidelines.

If you are interested in joining this project or have any questions, contact Dr. Hossein Mostafaei at 613-993-9729 or email Hossein.Mostafaei@nrc-cnrc.gc.ca.