Structural Timber Design to Eurocode 5

Structural Timber Design to Eurocode 5 is a comprehensive book which provides practising engineers and specialist contractors with detailed information and in-depth guidance on the design of timber structures based on the common rules and rules for buildings in Eurocode 5 - Part 1-1. It will also be of interest to undergraduate and postgraduate students of civil and structural engineering. The book provides a step-by-step approach to the design of all of the most commonly used timber elements and connections using solid timber, glued laminated timber or wood based structural products. It features numerous detailed worked examples, and incorporates the requirements of the UK National Annex. It covers the strength and stiffness properties of timber and its reconstituted and engineered products; the key requirements of Eurocode 0, Eurocode 1 and Eurocode 5 - Part 1-1; the design of beams and columns of solid timber, glued laminated, composite and thin-webbed sections; the lateral stability requirements of timber structures; and the design of mechanical connections subjected to lateral and/or axial forces as well as rigid and semi-rigid connections subjected to a moment. The Authors Jack Porteous is a consulting engineer specialising in timber engineering. He is a Chartered Engineer, Fellow of the Institution of Civil Engineers and Member of the Institution of Structural Engineers. He is a visiting scholar and lecturer in timber engineering at Napier University. Abdy Kermani is the Professor of Timber Engineering and R&D consultant at Napier University. He is a Chartered Engineer, Member of the Institution of Structural Engineers and Fellow of the Institute of Wood Science with over 20 years' experience in civil and structural engineering research, teaching and practice. The authors have led several research and development programmes on the structural use of timber and its reconstituted products. Their research work in timber engineering is internationally recognised and published widely. Also of Interest Timber Designers' Manual Third Edition E.C. Ozelton & J.A. Baird Paperback 978 14051 4671 5 Cover design by Garth Stewart

Table of Contents:
Preface. . 1. Timber as a Structural Material. 1.1 Introduction. 1.2 The structure of timber. 1.3 Types of timber. 1.3.1 Softwoods. 1.3.2 Hardwoods. 1.4 Natural characteristics of timber. 1.5 Strength grading of timber. 1.5.1 Visual grading. 1.5.2 Machine grading. 1.5.3 Strength classes. 1.6 Section sizes. 1.7 Engineered wood products (EWP). 1.7.1 Glued laminated timber (Glulam). 1.7.2 Plywood. 1.7.3 Laminated veneer lumber (LVL). 1.7.4 Laminated Strand Lumber (LSL), TimberStrand®. 1.7.5 Parallel Strand Lumber (PSL), Parallam®. 1.7.6 Oriented Strand Board (OSB). 1.7.7 Particleboards and fibre composites. 1.7.8 Thin webbed joists (I-joists). 1.7.9 Thin webbed beams (Box beams). 1.7.10 Structural Insulated Panels (SIPs). 1.8 Suspended timber flooring. 1.9 Adhesive bonding of timber. 1.10 Preservative treatment for timber. 1.11 Fire safety and resistance. 1.12 References. 2. Introduction to relevant Eurocodes. 2.1. Eurocodes – General Structure. 2.2. Eurocode 0 – Basis of structural design – (EC0). 2.2.1. Terms and definitions (EC0, 1.5). 2.2.2. Basic Requirements (EC0, 2.1). 2.2.3. Reliability Management (EC0, 2.2). 2.2.4. Design Working Life (ECO, 2.3). 2.2.5. Durability (EC0, 2.4). 2.2.6. Quality Management (EC0, 2.5). 2.2.7. Principles of limit state design – General (EC0, 3.1). 2.2.8. Design Situations (EC0, 3.2). 2.2.9. Ultimate limit states (EC0, 3.3). 2.2.10. Serviceability limit states (EC0, 3.4). 2.2.11. Limit state design (EC0, 3.5). 2.2.12. Classification of actions (EC0, 4.1.1). 2.2.13. Characteristic values of actions (EC0, 4.1.2). 2.2.14. Other representative values of variable actions (EC0, 4.1.3). 2.2.15. Material and product properties (EC0, 4.2). 2.2.16. Structural analysis (EC0, 5.1). 2.2.16.1. General. 2.2.16.1.1. Linear Elastic Analysis (based on linear stress/strain and moment/curvature laws). 2.2.16.1.2. Non-linear Analysis. 2.2.16.2. Structural analysis requirements for timber and wood based. structures. 2.2.17. Verification by the partial factor method - General (EC0, 6.1). 2.2.18. Design values of actions (EC0, 6.3.1). 2.2.19. Design values of the effects of actions (EC0, 6.3.2). 2.2.20. Design values of material or product properties (EC0, 6.3.3). 2.2.20.1. Load duration classes. 2.2.20.2. Service classes. 2.2.20.3. 2.2.21. Factors applied to a Design strength at the ULS. 2.2.22. Design values of geometrical data (EC0, 6.3.4). 2.2.23. Design resistance (EC0, 6.3.5). 2.2.24. Ultimate limit states (EC0, 6.4.1 to 6.4.5). 2.2.25. Serviceability limit states – General (EC0, 6.5). 2.2.25.1. Vibration. 2.2.25.2. Deflection. 2.3. Eurocode 5: Design of timber structures – Part 1-1: General – Common rules and rules for buildings (EC5). 2.3.1. General matters. 2.3.2. Serviceability limit states (EC5, 2.2.3). 2.3.3. Load duration and moisture content influences on strength (EC5, 2.3.2.1). 2.3.4. Load-duration and moisture influences on deformations (EC5, 2.3.2.2). 2.3.4.1. SLS Analyses. 2.3.4.2. ULS Analyses. 2.3.5. Stress-Strain relations (EC5, 3.1.2). 2.3.6. Size and stress distribution effects (EC5, 3.2, 3.3, 3.4 and 6.4.3). 2.3.7. System Strength (EC5, 6.6). 2.4. Symbols. 2.5. References. . 3. Using Mathcad® for Design Calculations . 3.1. Introduction. 3.2. What is Mathcad ? [1]. 3.3. What does Mathcad do ? [2]. 3.3.1. A simple calculation [2]. 3.3.2. Definitions and variables [2]. 3.3.3. Entering text [2]. 3.3.4. Working with units [2]. 3.3.5. Commonly used Mathcad functions. 3.3.5.1.Maximum and minimum values. 3.3.5.2.Conditional statement. 3.4. Summary. 3.5. References. 4. Design of members subjected to flexure. 4.1. Introduction. 4.2. Design considerations. 4.3. Design value of the effect of actions. 4.4. Member Span. 4.5. Design for Ultimate Limit States (ULS). 4.5.1. Bending. 4.5.1.1. Bending (where the relative slenderness ratio for bending about the major axis is ≤ 0.75). 4.5.1.2. Bending (where the relative slenderness ratio for bending about the major axis > 0.75). 4.5.1.3. Bending of notched members. 4.5.2. Shear. 4.5.2.1. Shear stress with a stress component parallel to the grain. 4.5.2.2. Shear stress with both stress components perpendicular to the grain (rolling shear). 4.5.3. Bearing (Compression perpendicular to the grain). 4.5.3.1. Bearing stress when the member is resting on supports. 4.5.3.2. Bearing stress when the member is resting on a continuous support. 4.5.4. Torsion. 4.5.5. Combined shear and torsion. 4.6. Design for Serviceability Limit States (SLS). 4.6.1. Deformation. 4.6.1.1. Deformation due to bending and shear. 4.6.1.2. Deformation due to compression over supports. 4.6.2. Vibration. 4.6.2.1. Machine enforced vibrations. 4.6.2.2. Footstep (Footfall) induced vibrations. 4.7. References. 4.8. Examples. 5. Design of members and walls subjected to axial or combined axial and flexural actions. 5.1. Introduction. 5.2. Design considerations. 5.3. Design of members subjected to axial actions. 5.3.1. Members subjected to axial compression. 5.3.2. Members subjected to compression at an angle to the grain. 5.3.3. Members subjected to axial tension. 5.4. Members subjected to combined bending and axial loading. 5.4.1. Where lateral torsional instability due to bending about the major axis will not occur. 5.4.2. Lateral torsional instability under the effect of bending about the. major axis. 5.4.3. Members subjected to combined bending and axial tension. 5.5. Design of Stud Walls. 5.5.1. Design of load-bearing walls. 5.5.1.1. Design of stud walls subjected to axial compression. 5.5.1.1.1. Stud design. 5.5.1.1.2. Plate design. 5.5.1.2. Design of stud walls subjected to combined out of plane bending and axial compression. 5.5.1.2.1. Stud design. 5.5.1.2.2. Plate design. 5.5.2. Lateral deflection of load-bearing stud walls (and columns). 5.6. References. 5.7. Examples. 6. Design of glued laminated members . 6.1. Introduction. 6.2. Design considerations. 6.3. General. 6.3.1. Horizontal and vertical glued laminated timber. 6.3.2. Design methodology. 6.4. Design of glued laminated members with tapered, curved or pitched curved profiles (also applicable to LVL members). 6.4.1. Design of single tapered beams. 6.4.2. Design of double tapered beams, curved and pitched cambered beams. 6.4.2.1. Bending and radial stress in the apex zone – for double tapered and pitched cambered beams. 6.4.2.1.1. Bending stress in the apex zone. 6.4.2.1.2. Radial stress in the apex zone. 6.4.2.2. Bending and radial stress in the apex zone – of a curved beam. 6.4.2.2.1. Bending stress in the apex zone. 6.4.2.2.2. Radial stress in the apex zone. 6.4.2.3. Bending strength in the apex zone – for double tapered beams, curved beams and pitched cambered beams. 6.4.2.4. Radial tensile strength in the apex zone – for double tapered beams, curved beams and pitched cambered beams. 6.4.2.5. Criterion for bending stress – for double tapered beams, curved beams and pitched cambered beams. 6.4.2.6. Criterion for radial tension stress – for double tapered beams, curved beams and pitched cambered beams. 6.4.3. Design of double tapered beams, curved and pitched cambered beams subjected to combined shear and tension perpendicular to the grain. 6.5. Finger joints. 6.6. References. 6.7. Examples. Annex 6.1 Deflection formulae for simply supported tapered and double tapered beams subjected to a point load at mid span or to a uniformly distributed load. Annex 6.2 Graphical representation of factors kℓ and kp used in the derivation of the bending and radial stresses in the apex zone of double tapered curved and pitched cambered beams.. 7. Design of composite timber and wood based sections. 7.1. Introduction. 7.2. Design considerations. 7.3. Design of glued composite sections. 7.3.1. Glued thin webbed beams. 7.3.1.1. Strength Analysis of glued thin webbed beams. 7.3.1.1.1. Stresses in the flanges. 7.3.1.1.2. Bending, shear and buckling stresses in the web. 7.3.1.2. Displacement at the SLS. 7.3.1.3. Strength Analysis of glued thin webbed beams. 7.3.1.3.1. 7.3.2. Glued thin flanged beams (Stressed skin panels). 7.3.2.1. Effective flange width. 7.3.2.2. Plate buckling. 7.3.2.3. Section properties. 7.3.2.4. Stresses in flanges. 7.3.2.5. Stresses in the web. 7.3.2.6. Deflection at the SLS. 7.4. References. 7.5. Examples. . 8. Design of built-up columns. 8.1. Introduction. 8.2. Design considerations. 8.3. General. 8.4. Bending stiffness of built-up columns. 8.4.1. The effective bending stiffness of built-up sections about the strong (y-y) axis. 8.4.2. The effective bending stiffness of built-up sections about the z-z axis. 8.4.3. Design procedure. 8.4.3.1.Design criteria for built-up sections. 8.4.4. Built-up sections - Spaced columns. 8.4.4.1. Design procedure for spaced columns. 8.4.5. Built-up sections - Latticed columns. 8.4.5.1. Design procedure for lattice columns. 8.5. Combined axial loading and moment. 8.6. Effect of creep at the ultimate limit state. 8.7. References. 8.8. Examples. 9. Design of stability bracing, floor and wall diaphragms . 9.1. Introduction. 9.2. Design considerations. 9.3. Lateral Bracing. 9.3.1. General. 9.3.2. Bracing of single members (subjected to direct compression) by local support. 9.3.3. Bracing of single members (subjected to bending) by local support. 9.3.4. Bracing for beam, truss or column systems. 9.4. Floor and roof diaphragms. 9.4.1. Limitations on the applicability of the method. 9.4.2. Simplified design procedure. 9.5. The in-plane racking resistance of timber walls under horizontal and vertical loading. 9.5.1. The in-plane racking resistance of timber walls using Method B in EC5. 9.6. References. 9.7. Examples. 10. Design of metal dowel type connections. 10.1. Introduction. 10.1.1. Metal dowel-type fasteners. 10.1.1.1. Nails. 10.1.1.2. Screws. 10.1.1.3. Dowels and bolts. 10.2. Design considerations. 10.3. Failure theory and strength equations for laterally loaded connections formed using metal dowel fasteners. 10.3.1. Dowel diameter. 10.3.2. Characteristic fastener yield moment (My,Rk). 10.3.3. Characteristic Embedment strength (fh). 10.3.3.1. Characteristic embedment strength when using nails (diameter ≤ 8mm). 10.3.3.2. Characteristic embedment strength when using staples. 10.3.3.3. Characteristic embedment strength when using bolts, nails. (diameter greater than 8mm) and dowels. 10.3.3.4. Characteristic embedment strength when using screws. 10.3.4. Member thickness, t1 and t2. 10.3.4.1. For a nail connection. 10.3.4.2. For a staple connection. 10.3.4.3. For a bolt connection. 10.3.4.4. For a dowel connection. 10.3.4.5. For a screw connection. 10.3.5. Friction effects and axial withdrawal of the fastener. 10.3.5.1. minimum penetration when using nails (EC5, 8.3.1.2 and 8.3.2). 10.3.5.2. minimum penetration when using staples(EC5, 8.4 (3)). 10.3.5.3. minimum penetration of screws (EC5, 8.7.2(3)). 10.3.6. Brittle failure. 10.3.6.1. Brittle failure due to connection forces at an angle to the grain. 10.4. Multiple dowel fasteners loaded laterally. 10.4.1. The effective number of fasteners. 10.4.1.1. Nails. 10.4.1.2. Staples. 10.4.1.3. Bolts and dowels. 10.4.1.4. Screws. 10.4.2. Alternating forces in connections. 10.5. Design Strength of a laterally loaded metal dowel connection. 10.5.1. Loaded parallel to the grain. 10.5.2. Loaded perpendicular to the grain. 10.6. Examples of the design of connections using metal dowel type fasteners. 10.7. Multiple shear plane connections. 10.8. Axial loading of metal dowel connection systems. 10.8.1. Axially loaded nails. 10.8.2. Axially loaded bolts. 10.8.3. Axially loaded dowels. 10.8.4. Axially loaded screws. 10.9. Combined Laterally and Axially loaded metal dowelled connections. 10.10. Lateral Stiffness of metal dowel connections at the SLS and ULS. 10.11. Frame analysis incorporating the effect of lateral movement in metal dowel fastener connections. 10.12. References. 10.13. Examples. . 11. Design of joints with connectors. 11.1. Introduction. 11.2. Design considerations. 11.3. Toothed-plate connectors. 11.3.1. Strength behaviour. 11.4. Ring and shear plate connectors. 11.4.1. Strength behaviour. 11.5. Multiple shear plane connections. 11.6. Brittle failure due to connection forces at an angle to the grain. 11.7. Alternating forces in connections. 11.8. Design strength of a laterally loaded connection. 11.8.1. Loaded laterally to the grain. 11.8.2. Loaded perpendicular to the grain. 11.8.3. Loaded at an angle to the grain. 11.9. Stiffness behaviour of toothed-plate, ring and shear-plate connectors. 11.10. Frame analysis incorporating the effect of lateral movement in connections formed using toothed plate, split ring or shear plate connectors. 11.11. References. 11.12. Examples. 12. Moment capacity of joints formed with metal dowel fasteners or connectors. 12.1. Introduction. 12.2. Design considerations. 12.3. The effective number of fasteners in a row in a moment connection. 12.4. Brittle failure. 12.5. Moment behaviour in timber joints – rigid model behaviour. 12.5.1. Assumptions in the connection design procedure. 12.5.2. Connection design procedure. 12.5.3. Splitting capacity and force component checks on connections subjected to a moment and lateral forces. 12.5.3.1. Splitting capacity. 12.5.3.2. Force component checks in a row of fasteners parallel to the grain. 12.6. The analysis of structures with semi-rigid connections. 12.6.1. The stiffness of semi-rigid moment connections. 12.6.2. The analysis of beams with semi-rigid end connections. 12.7. References. 12.8. Examples. . Appendix A: Weights of building materials. Appendix B: Related British Standards for Timber Engineering in buildings . Appendix C: Outline of Draft Amendment A1 to EN 1995-1-1. IndexThe Example Worksheets Disks Order Form

About the Author :
Jack Porteous is a consulting engineer specialising in timber engineering. He is a Chartered Engineer, Fellow of the Institution of Civil Engineers and Member of the Institution of Structural Engineers. He is a visiting scholar and lecturer in timber engineering at Napier University. Abdy Kermani is the Professor of Timber Engineering and R&D consultant at Napier University. He is a Chartered Engineer, Member of the Institution of Structural Engineers and Fellow of the Institute of Wood Science with over 20 years’ experience in civil and structural engineering research, teaching and practice. The authors have led several research and development programmes on the structural use of timber and its reconstituted products. Their research work in timber engineering is internationally recognised and published widely. Jack Porteous is a consulting engineer specialising in timber engineering. He is a Chartered Engineer, Fellow of the Institution of Civil Engineers and Member of the Institution of Structural Engineers. He is a visiting scholar and lecturer in timber engineering at Napier University. Abdy Kermani is the Professor of Timber Engineering and R&D consultant at Napier University. He is a Chartered Engineer, Member of the Institution of Structural Engineers and Fellow of the Institute of Wood Science with over 20 years’ experience in civil and structural engineering research, teaching and practice. The authors have led several research and development programmes on the structural use of timber and its reconstituted products. Their research work in timber engineering is internationally recognised and published widely.

Review :
"This is a must for all those involved in timber structures, their design and all things timber." (Building Engineer) "This is a must for all those involved in timber structures, their design and all things timber." (Building Engineer) "This is a must for all those involved in timber structures, their design and all things timber." (Building Engineer) "This is a must for all those involved in timber structures, their design and all things timber." (Building Engineer)