As we are about to begin the summer term at York University, we have a number of news items and scholarship announcements to share.
The past few days we have been sorting through the structures lab after the end of the last academic year. Among the materials which we were indexing and storing were the heritage timbers that we tested for the CSCE paper (posted below). The timbers were installed in a heritage building built approximately in 1890 or so. In a retrofit of a building they were removed. We tested the timber beam first in structural loading. The beam was tested for our second year undergrads to see. Then we extracted two planks from the timber as it only had moderate damage for flame spread testing (to be compared to modern engineered lumber of the same moisture content). Since then the planks have sat. Looking at the timbers myself and Mina Li, opted to count the tree rings this week to estimate the timbers age yesterday. Relating to Canada’s 150 we were in for a bit of a shock.
Our research team traveled to Naples Italy to attend the IfireSS conference. Ben Nicoletta presented his paper to a keen audience. The paper, Performance of Gfrp stay-in- place Form work for Bridge Dec ks after Real and Simulated Fire Damage (download here) was an interesting work with collaboration from University of Waterloo and Queen’s University. It is a preliminary study which we are currently developing into a larger project. Ben’s hard work paid off and he won best paper at the conference. Currently Ben is interning in a joint research collaboration with the global consultancy firm Entuitive (via graduate Matt Smith). Ben was supported at the conference by research team students Hailey Todd and Chloe Jeanneret. Chloe is performing an internship with Dr. Guillermo Rein’s Haze Lab at Imperial College and the trip was not too far for her. Hailey is working on stadium design.
Very exciting to announce that effective this year I am joining John Wiley’s journal, Fire and Materials as an Associate Editor. In this role I will be considering mainly the structural materials papers. Fire and Materials is one of the more older peer reviewed journals for our research community beginning in 1976. The journal is led by Steven Grayson. More information is to come on this initiative. For now be sure to check out my own Fire and Materials paper on the Creep of Prestressing steel which can be downloaded here .
Research team member, Matthew Smith, and Engineer at global consulting firm, Entuitive, successfully defended his masters thesis: Towards a Performance-Based Fire Design Framework for Composite Steel Deck Construction in Canada . His thesis and defense were of the highest quality that there were no corrections necessary. Matt was subsequently nominated for the university’s senate medal (he has also just been awarded the SFPE National Capital Region Chapter Scholarship in Fire Safety Engineering in Canada for his work. A big thank you to his examiners whom I would say have a combined experience of over 60 years practicing steel construction. Also a big thank you to project sponsors: CISC and Entuitive, as well as to reps from FM Global and the National Research Council, NIST for their previous feedback and contributions.
The MGM Grand Fire occurred on November 21st 1980. It represents a significant case study in the study of Human Behavior in fire as well as for smoke dynamics. About 87 people were killed in this fire. Recently I had a chance to visit and talk to certain staff members at the current building over 35 years later. There are many rumors associated to the fire today but I thought a visual representation is quite telling when you compare the building to other hotels on the strip in Las Vegas. Most people are completely unaware that the building is still standing today.
Ive included some more recent photos herein. To many who visit the current building there is not much remembrance to the fire that is obvious to the casual pedestrian walking by. If you search really hard there really isn’t a plaque talking about the fire that is visible. However there are many reminders present if you look carefully as the included imagery resonates. The patrons are oblivious to what happened for the most part., although some online do contend the buildings haunting and unusual activities – though i dont advise talking about these stories within the building or near by as many are sensitive to these types of stories. Images posted for reflection to those keen on our disciplines history.
Ill talk more on this at a later date.
Our team is very excited to be travelling to the Interflam conference this year. There we will be presenting 4 papers in posters and oral presentations. Papers have primarily been led by students on the team and involve a great and diverse set of collaborators. The conference is this July 4th through 6th in the UK. In no order a brief description of each is below:
Design For Elderly Egress In Fire Situations. By Folk, L., Gales, J., Gwynne, S., Kinsey, M.
The paper represents a follow up to our Human Behavior in Fire Symposium paper last fall. The work deals with aging populations and evacuation modelling. It is a lead on to a new grant from NSERC Canada in collaboration with Arup.
Behaviour of Char Layer in Fire-Damaged Box Section Timber Beams. By Quiquero, H., Gales, J., and Hadjisophocleous, G
The work is the product of a NSERC student scholar’s research by Quiquero and is a follow on to her Canadian Society of Civil Engineers study on mechanics of Timber beams after exposure from severe temperature exposure., That will be presented this month.
Improving Fire Safety Of Glass Fibre Reinforced Polymers For Bridge Infrastructures. By Gales, J., Nagy, N., Weckman., B., Gaudreault, C., and Smith, H.
The work is based on a novel materials in fire collaboration between the University of Waterloo and Carleton University. Thoughts and insights into improving fire performance of composite polymers are discussed.
Post-fire Guidance for the Critical Temperature of Prestressing Steel. By Roberston, L., and Gales, J.
This work follows my steel in fire forum presentation that illustrated that post fire guidance given about the strength of prestressing steel after fire, may be in need of revision. Results of over 100 tests are used to support these preliminary conclusions.
The conference should be an exciting time this July to present these papers, see other’s studies and catch up with old colleagues from across the ‘pond’. Other conference updates will be posted soon.
Our new paper, Creep of Prestressing Steels in fire, is now in press in the journal Fire and Materials (you can access it here; an open access version is to come). It is a great piece about prestressing steels used in Post-tensioned structures. We show how high- temperature creep is effected by the chemical composition of the steel. While it may seem obvious to some, the effect this can have for prestressing steel in high temperatures seen in real fires is astounding.
Consider several different prestressing steels, all behaving the same in ambient service temperatures, but when stressed and heated (700 MPa and 427C) as if they were in a fire, one fails after 5 hours, were the others fail below 1.5 hours. All likely due to the chemical composition from the production process of the steel (see the above figure). These tests are described in the paper (that and about 80 others). The same trends shows the same effect in simple strength tests at high temperature.
The paper also describes the use of digital image correlation to measure the strain at high high temperature. An innovated technique, but leading to important insights about true areas and strains as the steel fails in high temperature. A compiled video of a creep test is provided below which illustrates how quickly tertiary (third stage) creep takes effect before failure.
The above video shows the prestressing steel coated in a black and white speckle texture pattern. Image correlation is a powerful technique for measuring high temperature strains. Its a very simple process described below
There is no question when you travel through Toronto you look to the sky and imagine the possibilities for iconic structures and you do see first hand the structural revolution occurring there. And more so, if your aware, you ask what this means for Canadian fire engineering design. Buildings are becoming very complex.
In Toronto alone, there are now over 25 buildings that are 50 stories or higher. Nearly 15 are under construction and nearly 30 are approved and/or proposed. Even in Ottawa there are about five or so proposed.
So how do you convey and prepare university students what innovative and complex designs may be like? How might you inspire them beyond designing a ‘box’? There is the cheap route – take them down to Toronto and show them first hand the newly designed buildings there; or maybe the more elaborate route and show them designs abroad (not necessary tall per say, but significant nevertheless). In Canada we have begun to push the envelope in fire engineering design, but in the United Kingdom for example, there has been a lot of attention given to fire engineering – specifically to complex buildings.
Recently two research students and myself traveled to London UK (a third went to Cambridge, UK the week after for the Human Behaviour in Fire symposium – Ill talk on that later). This was in an effort to illustrate to how iconic and fire engineered structures are designed abroad and allow a bit of comparative thought to what we do in Canada. The students presented their current research to some of the world’s largest engineering firms and had the opportunity to speak one on one with designers (many whom inspired my own career) about the challenges being faced abroad; particularly in respect to structural fire engineering.
Beyond this ‘city’ class room, the students attended the Steel in Fire Forum, where one of them presented her research to a captive audience (you can see her presentation slides here). The Steel in Fire forum is merging with the Concrete in fire forum, and this was the ‘last’ session. I find it fitting that a student gave the last presentation as I believe fire safety engineering’s biggest challenges are in education, particularly in Canada (but that is discussion for another day). Above all it was fantastic that so many people took so much time to accommodate the students and myself to teach about what structural design is like in the United Kingdom, one of the world’s best examples for iconic structure construction. The trip will certainly provoke the students into thought on what they see today and possibly will see tommorrow in design.