Designing Steel Structures for Fire Safety

Structural design in fire conditions is conceptually similar to structural design in normal temperature conditions, but often more difficult because of internal forces induced by thermal expansion, strength reduction due to elevated temperatures, much larger deflections, and numerous other factors. Before making any design decisions it is esse

Table of Contents:
CHAPTER 1 - INTRODUCTION 1.1 Fire safety design 1.2 Codes and standards 1.2.1 General 1.2.2 Fire safety codes 1.2.3 North American codes and standards 1.2.4 European codes: the Eurocodes 1.3 Design for fire resistance 1.3.1 Fire resistance requirements 1.3.2 Fire resistance assessment 1.3.3 Eurocodes 1.3.4 Scope of Eurocode 3 - Fire part 1.4 General layout of this book CHAPTER 2 - MECHANICAL LOADING 2.1 Fundamental principles 2.1.1 Eurocodes load provisions 2.1.2 American provisions for fire design 2.2 Examples 2.2.1 Office building 2.2.2 Beam for a shopping centre 2.2.3 Beam in a roof 2.3 Specific considerations 2.3.1 Simultaneous occurrence 2.3.2 Dead weight 2.3.3 Upper floor in an open car park 2.3.4 Industrial cranes 2.3.5 Indirect fire actions 2.3.6 Simplified rule CHAPTER 3 - THERMALACTION 3.1 Fundamental principles 3.1.1 Eurocode temperature-time relationships 3.1.1.1 Nominal fire curves 3.1.1.2 Equivalent time 3.1.1.3 Parametric temperature-time curves 3.1.1.4 Zone models 3.1.1.5 Heat exchange coefficients 3.1.2 Eurocode localised fire, flame not impacting the ceiling 3.1.3 Eurocode localised fire, flame impacting the ceiling 3.1.4 CFD models in the Eurocode 3.4.5 North American time-temperature relationships 3.2 Specific considerations 3.2.1 Heat flux to protected steelwork 3.2.2 Combining different models 3.3 Examples 3.3.1 Localised fire 3.3.2 Parametric fire-ventilation controlled 3.3.3 Parametric fire-fuel controlled CHAPTER 4 - TEMPERATURE IN STEEL SECTIONS 4.1 General 4.2 Unprotected internal steelwork 4.2.1 Principles 4.2.2 Examples 4.2.2.1 Rectangular hollow core section 4.2.2.2 I-section exposed to fire on 4 sides and subjected to a nominal fire 4.2.2.3 I-section exposed to fire on 3sides 4.3 Internal steelwork insulated by fire protection material 4.3.1 Principles 4.3.2 Examples 4.2.2.1 H section heated on four sides 4.2.2.2 H section heated on three sides 4.4 Internal steelwork in avoid protected by heat screens 4.5 External steelwork 4.5.1 General principles 4.5.2 Example CHAPTER 5 - MECHANICAL ANALYSIS 5.1 Level of analysis 5.1.1 Principles 5.1.2 Boundary conditions in a substructure or an element analysis 5.1.3 Determining Efi,d 0 5.2 Different calculation models 5.2.1 General principle 5.2.1.1 Tabulated data 5.2.1.2 Simple calculation models 5.2.1.3 Advanced calculation models 5.2.2 Relations between the calculation model and the part of the structure that is analysed 5.2.3 Calculation methods in North America 5.3 Load, time or temperature domain 5.4 Mechanical properties of carbon steel 5.5 Classification of cross-sections 5.6 How to calculate Rfi,d,t ? 5.6.1 General principles 5.6.2 Tension members 5.6.3 Compression members with Class 1, 2 or 3 cross-sections 5.6.4 Beams with Class1, 2 or 3 cross-section 5.6.4.1 Resistance in shear 5.6.4.2 Resistance in bending 5.6.4.2.1 Uniform temperature distribution 5.6.4.2.2 Non-uniform temperature distribution 5.6.4.3 Resistance to lateral torsional buckling 5.6.5 Members with Class 1, 2 or 3 cross-sections, subject to combined bending and axial compression 5.6.6 Members with Class 4 cross-sections 5.7 Design in the temperature domain 5.8 Design examples 5.8.1 Member in tension 5.8.1.1 Verification in the load domain 5.8.1.2 Verification in the time domain 5.8.1.3 Verification in the temperature domain 5.8.2 Column under axial compression 5.8.2.1 Fire resistance time of the column with unprotected cross-section 5.8.2.2 Column protected with contour encasement of uniform thickness 5.8.3 Fixed-fixed beam supporting a concrete slab 5.8.3.1 Classification of the section, see Table 5.2 5.8.3.2 Verification in the load domain 5.8.3.3 Verification in the time domain 5.8.3.4 Verification in the temperature domain 5.8.3.5 Beam protected with hollow encasement 5.8.4 Class 3 beam in lateral torsional buckling CHAPTER 6 - JOINTS 6.1 General 6.2 Simplified procedure 6.3 Detailed analysis 6.3.1 Temperature of joints in fire 6.3.2 Design resistance of bolts and welds in fire 6.3.2.1 Bolted joints in shear 6.3.2.2 Bolted joints in tension 6.3.2.3 Fillet welds 6.3.2.4 Butt welds CHAPTER 7 - ADVANCED CALCULATION MODELS 7.1 General 7.2 Introduction 7.3 Thermal analysis 7.3.1 General features 7.3.2 Capabilities of the advanced thermal models 7.3.3 Limitations of the advanced thermal models 7.3.4 Discrepancies with the simple calculation models 7.4 Mechanical analysis 7.4.1 General features 7.4.2 Capabilities of the advanced mechanical models 7.4.3 Limitations of the advanced mechanical models 7.4.4 Discrepancies with the simple calculation models CHAPTER 8 - DESIGN EXAMPLES 8.1 General 8.2 Continuous beam 8.3 Multi-Storey moment resisting frame 8.4 Single storey industrial building 8.5 Storage building ANNEX I - HIGH TEMPERATURE PROPERTIES AND TEMPERATURE PROFILES I.1 Thermal properties of carbon steel I.1.1 Eurocode properties I.1.1.1 Thermal conductivity I.1.1.2 Specific heat I.1.2 Thermal properties of steel according to ASCE Thermal conductivity Specific heat I.2 Thermal properties of fire protection materials I.3 Temperatures in unprotected steel sections (Eurocode properties) I.4 Temperatures in protected steel sections (Eurocode properties) ANNEX II - MECHANICAL PROPERTIES OF CARBON STEELS II.1 Eurocode properties II.1.1 Strength and deformation properties II.1.2 Thermal elongation II.2 ASCE properties II.2.1 Stress strain relations for steel (Version 1) II.2.2 Stress strain relations for steel (Version 2 II.2.3 Coefficient of thermal expansion Bibliography Subject index

About the Author :
Venkatesh Kodur, Jean Marc Franssen, Raul Zaharia