Full Session with Abstracts
High-rise mass timber construction is restricted by current building codes. The International Building Code (IBC) classifies timber construction as Types III, IV, and V. These three types require an increased level of fire protection and both Type III and IV have a height limitation of 85 feet. In order for timber construction to exceed the code limitations, extensive structural testing is required. This testing process is time consuming, expensive, and adds additional risk to a project. The authors tested four timber-concrete composite floors in a gas-fire furnace at the National Research Council (NRC) in Canada. Specimens were tested under service loading conditions and the standard fire curve (ASTM E119). The objective of this research is to collect data on the fundamental behavior of timber-concrete composite floors in fire. The results will provide practicing engineers with testing data that can be used to demonstrate adequate fire performance of timber-concrete composite floors, and researchers with experimental data to benchmark numerical modeling techniques. This research is part of a larger study that consists of fire testing of four different timber-concrete floors. The authors focus on two specimens for this presentation. The specimens were: (1) 5-ply cross-laminated timber (CLT) with 2½” normal weight concrete, and (2) 2x8 nail-laminated timber (NLT) with 3½” normal weight concrete. The panels spanned 16 feet and were 4 feet wide. The concrete is reinforced with W2x2 wire mesh on a 6x6 grid. Shear connector VG CYL type screws will be utilized to achieve composite action between the timber panels and the concrete slab. The panels will be loaded to simulate a distributed live load equal to 80 psf. The data collected will consist of temperature distribution along the length of the floors and through the thickness of the timber panels. Displacement measurements will be obtained throughout the test through the use of string potentiometers. This work is in collaboration with many different industry partners that are actively working on mass timber buildings. These include: KPFF, Skidmore Owings & Merrill, Katerra, Arup, Forest Products Laboratory, and WoodWorks. Structural fire testing capabilities are being developed at Oregon State University. The data collected from this research will be used to benchmark the testing capabilities.