Best practice guidelines for structural fire resistance design of concrete and steel buildings

Abstract

This document is intended to provide practicing engineers and building code officials with a technical resource that contains the current "best practice" for fire-resistant design of concrete and steel structures. The report provides a review of existing U.S. and international guidelines and design standards, which use approaches that range from simple prescriptive methods to sophisticated software programs with advanced methods of analysis under a wide range of realistic fire conditions. Basic concepts of risk-informed decision making for mitigating fire risk, and a general framework for assessing fire risk to building construction and for developing structural design requirements for fire conditions are described. Current best knowledge in thermal and mechanical properties and behaviors of normal strength concrete, high strength concrete, structural steel, and several major groups of common fire protection materials at elevated temperatures, which are necessary for performance-based engineering calculation, are presented. Modern fire-resistant design methodologies for concrete and steel structures are discussed, including methods based on standard fire tests as well as performance-based engineering analysis methods that involve heat transfer and structural analysis at elevated temperatures.This report is not intended to provide step-by-step design procedures. Rather, it provides general guidance on the approaches to, and practical aspects of, implementing a fire-resistant design approach for concrete and steel buildings. The guidance includes key concepts and examples for identifying performance objectives, conducting risk analyses, selecting design fire scenarios and fire exposure curves, and implementing heat transfer and structural response analyses for the structural fire-resistant design of concrete and steel structures.The best practice guidelines document is intended to be a technical resource that provides the most complete information for structural fire-resistant design at present. The document is a nonconsensus, non-mandatory document and, as such, it does not represent a minimum standard of care.

Temperature-Dependent Material Modeling for Structural Steels: Formulation and Application

“…Modeling the performance of these steels, for example for performance-based design (Phan et al, 2010), requires that the model parameters reflect the enhanced performance. The Eurocode 3 (ECS, 2005) model provides no guidance on how steels with improved (or different) hightemperature performance might be modeled, though in principle new parameters for the retained strength, proportional limit, and modulus could be chosen.…”

Fire Performance of Reinforced Concrete Slabs: Direct Flame Effects

“…The literature review also identifies a number of factors that can affect the behaviour of concrete in fire. These factors include the type of concrete, the mix proportions, the aggregate type, the reinforcement type and the fireexposure conditions (Khoury, 2005;Cravel et al, 2005;Lucia et al, 2005, Ulrich, 1998Annelies, 2011;Long et al, 2010). Schneider (1988) and Terro (1998) conducted studies on the mechanical properties of concrete and reinforcing steel after cooling off and after the completion of the fire, including flexural strength, compressive strength and stress-strain behaviour.…”

Fire-Exposed Fly-Ash-Based Geopolymer Concrete: Effects of Burning Temperature on Mechanical and Microstructural Properties

“…At present, fire events that are caused by the ignition or explosion of hydrocarbon-based fuels in the built environment are common. These events induce a rapid rise in temperature from the flashover state to more than 1100 °C within a few minutes [ 1 , 2 ]. In light of the occurrence of destructive fire events, fire resistance has become one of the most important properties of construction materials.…”