The concept of combining folded thin steel plates and glued laminated timber in the beam element to gain increased structural and fire performances was developed at the Institute of Structural Design and Timber Engineering (ITI) in Vienna University of Technology...
The objective of this work is to generate fire performance data for NLT assemblies to address gaps in technical knowledge. This project aims to study how the size of gaps between NLT boards might affect charring of an assembly and its overall fire performance. This research will support designers and builders in the use of mass timber assemblies in larger and taller buildings, by ensuring fire safe designs.
Cross-laminated timber (CLT) is well known as an interesting technical and economical product for modern wood structures. The use of CLT for modern construction industry has become increasingly popular in particular for residential timber buildings. Analyzing the CLT behavior in high thermal environment has attracted scholars’ attention. Thermal environment greatly influences the CLT properties and load bearing capacity of CLT, and the investigation can form the basis for predicting the structural response of such CLT-based structures. In the present work, the finite element method (FEM) is employed to analyze the thermal influence on the deformation of CLT. Furthermore, several factors were taken into consideration, including board layer number, hole conformation, and hole position, respectively. In order to determine the influence, several numerical models for different calculation were established. The calculation process was validated by comparing with published data. The performance is quantified by demonstrating the temperature distribution and structural deformation.
The advanced calculation methods for wood structural elements in fire situations proposed by EN1995-1-2 provide reduction factors of wood strength according to the temperature. The values of these reduction factors given for compression and tension strength are relatively well documented. However, the reduction factors of wood shear strength with temperature were not studied. This study concerns experimental investigations conducted to characterize the evolution with temperature of the shear strength of wood. The tests are realized using a specific original specimen specially developed for this study. The experimental results allow evaluating the values given in EN1995-1-2.
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, four large-scale fire experiments were conducted to evaluate the fire performance of two forms of encapsulated combustible structural wood systems, a lightweight wood-frame (LWF) system (2 experiments [3, 4]) and a crosslaminated timber (CLT) system (1 experiment). The fourth experiment  involved a test structure constructed using a steel frame system described below. Each experiment involved construction of a test set-up of an unsprinklered full-size apartment unit, intended to represent a portion of a mid-rise (e.g. six-storey) building.
The structural elements used in the LWF system (wood stud walls and wood I-joist floors) and CLT system (3-ply wall panels and 5-ply floor panels) were all chosen on the basis of the types of construction that were currently being used in 5- and 6-storey mid-rise residential construction being built in the province of British Columbia, where the building code had changed earlier, in 2009, to permit such mid-rise combustible construction. This report provides the results of the experiment with an encapsulated CLT setup representing an apartment in a mid-rise (e.g. six-storey) building.
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. A key parameter in the use of encapsulation materials to protect wood structural elements is the ignition temperature of wood. In this report, a brief overview of wood ignition is provided. In addition, the results of limited cone calorimeter testing to determine the ignition characteristics of OSB and torrefied wood are discussed. The ignition temperature of plywood used as a substrate for cone calorimeter tests with encapsulation materials is also provided.