This report begins with a discussion of the mechanisms of flame spread over combustible materials while describing the NBCC prescriptive solutions that establish the acceptable fire performance of interior finish materials. It is noted that while flame spread ratings do give an indication of the fire performance of products in building fires, the data generated are not useful as input to fire models that predict fire growth in buildings.
The cone calorimeter test is then described in some detail. Basic data generated in the cone calorimeter on the time to ignition and heat release rates are shown to be fundamental properties of wood products which can be useful as input to fire models for predicting fire growth in buildings.
The report concludes with the recommendation that it would be useful to run an extensive set of cone calorimeter tests on SCL, glue-laminated timber and CLT products. The fundamental data could be most useful for validating models for predicting flame spread ratings of massive timber products and useful as input to comprehensive computer fire models that predict the course of fire in buildings. It is also argued that the cone calorimeter would be a useful tool in assessing fire performance during product development and for quality control purposes.
Timber buildings made with Cross-laminated Timber (CLT) panels are becoming wide spread in Europe. The fire resistance of CLT panels depends upon several parameters, including the number of layers and their thickness. At the present, EN 1995-1-2:2004 does not provide specific information on the fire design of CLT panels. Several fire resistance tests of CLT panels were performed in different scales by furnace testing using the standard fire curve according to ISO 834-1:1999, however the large number of possible combination of CLT products makes testing too complicated and expensive as a tool for the verification of the fire resistance of several combinations. In this report are presented nine small-scale tests carried-out at SP Wood Technology (Technical Research Institute of Sweden). The tests consisted in specimens of CLT and massive timber exposed at a two steps of constant heat flux in a cone calorimeter (50 and 75 kW/m2). Some specimens were exposed with two different types of fire protection (gypsum plasterboard type F and plywood) and some were tested unprotected. Later, thermal simulations with the same set-up of tests were implemented on the finite element software package in Safir 2007, with the time-temperature curve given by ISO 834 as input; also the analytical calculation of the charring depth following the Eurocode 5 part 1-2 was done. The target of this thesis is to compare performed CLT furnace tests with the smallscale cone calorimeter tests carried out, the numerical results of the thermal model and the analytical results obtained.
Project contact is Christian Dagenais at Université Laval
The use of materials in a building is traditionally determined from its combustibility (via ULC S114 or ULC S135) and by its flame propagation index (via ULC S102). The ULC S102 Flame Spread Test, developed in 1943, has historically reduced risk through its method of classifying materials. However, this test does not provide quantitative information on the combustion properties of materials, such as heat flow. The latter is one of the most important variables in the development of a fire. Thus, a new approach would be preferable in order to review the classification of materials according to ULC S102 and ULC S135 (cone calorimeter). The objective of this project is to develop a new approach to classifying materials based on cone calorimeter test results. These results can subsequently be used in numerical modeling as part of a fire safety engineering design. A significant amount of cone calorimeter (ULC S135) testing of materials currently evaluated according to ULC S102 will be required.
A research project, Wood and Wood-Hybrid Midrise Buildings, was undertaken to develop information to be used as the basis for alternative/acceptable solutions for mid-rise construction using wood structural elements. As part of this project, three materials were selected for investigation as encapsulation materials for combustible structural elements: Type X gypsum board (12.7 mm thick and 15.9 mm thick), cement board (12.7 mm thick), and gypsum-concrete (25 mm thick and 39 mm thick). This report documents the results of cone calorimeter tests conducted to investigate the performance of the three encapsulation materials.
One of the tasks in the project, Wood and Wood-Hybrid Midrise Buildings, was to develop further information and data for use in developing generic exterior wall systems for use in mid-A1-100035-01.3 3 rise buildings using either lightweight wood frame or cross-laminated timber as the structural elements. As a result, full-scale standard exterior wall assembly tests were conducted to CAN/ULC-S134.
The foam insulations examined for use in the full-scale test assemblies were typical of those used in present-day construction. In addition, a non-standard test (Test EXTW-5) was conducted using a reduced scale rain screen wall system.
In addition to the full-scale tests, cone calorimeter tests were conducted to select and characterize the foam insulation, water resistant barrier and FRT plywood materials, as well as the regular gypsum sheathing, used in the full-scale tests. Tests were also conducted with the foam insulations protected using the sheathing materials used in the full-scale tests. The results of the cone calorimeter tests are provided in this report.