Contenido Design and Analysis of Connections in Steel Structures: Fundamentals and Examples

The book introduces all the aspects needed for the safe and economic design and analysis of connections using bolted joints in steel structures. This is not treated according to any specific standard but making comparison among the different norms and methodologies used in the engineering practice, e.g. Eurocode, AISC, DIN, BS.
Several examples are solved and illustrated in detail, giving the reader all the tools necessary to tackle also complex connection design problems.

The book is introductory but also very helpful to advanced and specialist audiences because it covers a large variety of practice demands for connection design. Parts that are not taken to an advanced level are seismic design, welds, interaction with other materials (concrete, wood), and cold formed connections./p

TABLE CONTENTS


Acknowledgments xxi

List of Abbreviations xxiii

1 Fundamental Concepts of Joints in Design of Steel Structures

1.1 Pin Connections and Moment Resisting Connections
   1.1.1 Safety, Performance, and Costs
   1.1.2 Lateral Load Resisting System
   1.1.3 Pins and Fully Restrained Joints in the Analysis Model
1.2 Plastic Hinge
   1.2.1 Base Plates
   1.2.2 Trusses
References

2 Fundamental Concepts of the Behavior of Steel Connections

2.1 Joint Classifications
2.2 Forces in the Calculation Model and for the Connection
2.3 Actions Proportional to Stiffness
2.4 Ductility
2.5 Load Path
2.6 Ignorance of the Load Path
2.7 Additional Restraints
2.8 Methods to Define Ultimate Limit States in Joints
2.9 Bolt Resistance
2.10 Yield Line
2.11 Eccentric Joints
2.12 Economy, Repetitiveness, and Simplicity
2.14 Diffusion Angles
2.15 Bolt Pretensioning and Effects on Resistance
   2.15.1 Is Resistance Affected by Pretensioning?
   2.15.2 Is Pretensioning Necessary?
   2.15.3 Which PretensioningMethod Should Be Used?
2.16 Transfer Forces
2.17 Behavior of a Bolted Shear Connection
2.18 Behavior of Bolted Joints Under Tension
References

3 Limit States for Connection Components

3.1 Deformation Capacity (Rotation) and Stiffness
   3.1.1 Rotational Stiffness
3.2 Inelastic Deformation due to Bolt Hole Clearance
3.3 Bolt Shear Failure
   3.3.1 Threads Inside the Shear Plane
   3.3.2 Number of Shear Planes
   3.3.3 Packing Plates
   3.3.4 Long Joints
   3.3.5 Anchor Bolts
   3.3.6 Stiffness Coefficient
3.4 Bolt Tension Failure
   3.4.1 Countersunk Bolts
   3.4.2 Stiffness Coefficient
3.5 Bolt Failure in Combined Shear and Tension
3.6 Slip-Resistant Bolted Connections
   3.6.1 Combined Shear and Tension
3.7 Bolt Bearing and Bolt Tearing
    3.7.1 Countersunk Bolts
    3.7.2 Stiffness Coefficients
3.8 Block Shear (or Block Tearing)
3.9 Failure ofWelds
   3.9.1 Weld Calculation Procedures
      3.9.1.1 DirectionalMethod
      3.9.1.2 Simplified Method
3.9.2 TackWelding (Intermittent FilletWelds)
3.9.3 Eccentricity
3.9.4 FilletWeld Groups
3.9.5 Welding Methods
3.9.6 Inspections
   3.9.6.1 Visual Testing
   3.9.6.2 Penetrant Testing
   3.9.6.3 Magnetic Particle Testing
   3.9.6.4 Radiographic Testing
   3.9.6.5 Ultrasonic Testing
3.10 T-stub, Prying Action
   3.10.1 T-stub with Prying Action
   3.10.2 Possible Simplified Approach According to AISC
   3.10.3 Backing Plates
   3.10.4 Length Limit for Prying Forces and T-stub without Prying
   3.10.5 T-stub Design Procedure for Various “Components” According to Eurocode
      3.10.5.1 Column Flange
      3.10.5.2 End Plate
      3.10.5.3 Angle Flange Cleat 71
      3.10.6.1 ????eff for Equivalent T-stubs for Bolt Row Acting Alone
      3.10.6.2 ????eff to Consider for a Bolt Row Acting Alone
      3.10.6.3 ????eff to Consider for Bolt Rows Acting in Group
      3.10.6.4 Examples of ????eff for Bolts in a Group
   3.10.7 T-stub for Bolts Outside the Beam Flanges
   3.10.8 Stiffness Coefficient
3.11 Punching
3.12 Equivalent Systems
3.13 Web Panel Shear
   3.13.1 Stiffness Coefficient
3.14 Web in Transverse Compression
   3.14.1 Transformation Parameter ????
   3.14.2 Formulas for Other Local Buckling Limit States
   3.14.3 Stiffness Coefficient
   3.14.4 T-stub in Compression
3.15 Web in Transverse Tension
   3.15.1 Stiffness Coefficient
3.16 Flange andWeb in Compression
3.17 BeamWeb in Tension
3.18 Plate Resistance
   3.18.1 Material Properties
   3.18.2 Tension
     3.18.2.1 Staggered Bolts
   3.18.3 Compression
   3.18.5 Bending
   3.18.6 Design for Combined Forces
   3.18.7 Whitmore Section
3.19 Reduced Section of Connected Profiles
   3.19.1 Shear Lag
3.20 Local Capacity
3.21 Buckling of Connecting Plates 1
   3.21.1 Gusset Plate Buckling
   3.21.2 Fin Plate (Shear Tab) Buckling
3.22 Structural Integrity (and Tie Force)
3.23 Ductility
3.24 Plate Lamellar Tering
3.25 Other Limit States in Connections with Sheets and Cold-formed Steel Sections
3.26 Fatigue
3.27 Limit States of Other Materials in the Connection
References

4 Connection Types: Analysis and Calculation Examples

4.1 Common Symbols
   4.1.1 Materials
   4.1.2 Design Forces
   4.1.3 Bolts
4.2 Eccentrically Loaded Bolt Group: Eccentricity in the Plane of the Faying Surface
   4.2.1 Elastic Method
   4.2.1.1 Example of Eccentricity Calculated with Elastic Method
   4.2.2 Instantaneous Center-of-Rotation Method
   4.2.2.1 Example of Eccentricity Calculated with the Instantaneous Center-of-Rotation Method
4.3 Eccentrically Loaded Bolt Group: Eccentricity Normal to the Plane of the Faying Surface
   4.3.1 Neutral Axis at Center of Gravity
     4.3.1.1 Example of Eccentricity Normal to Plane Calculated with Neutral Axis at Center-of-Gravity Method
   4.3.2 Neutral Axis Not at Center of Gravity 123
     4.3.2.1 Example of Eccentricity Normal to Plane Calculated with Neutral Axis not at Center-of-Gravity Method 124
4.4 Base Plate with Cast Anchor Bolts
   4.4.1 Plate Thickness
     4.4.1.1 AISC Method
     4.4.1.2 Eurocode Method
   4.4.2 Contact Pressure
     4.4.2.1 AISC Method
     4.4.2.2 Eurocode Method
   4.4.3 Anchor Bolts in Tension
     4.4.3.1 AISC Method 139
     4.4.3.2 Eurocode Method
     4.4.3.3 Other Notes
   4.4.4 Welding
   4.4.5 Shear Resistance
     4.4.5.1 Friction
     4.4.5.2 Anchor Bolts in Shear
     4.4.5.3 Shear Lugs
4.4.6 Rotational Stiffness
4.4.7 Measures to Improve Ductility
4.4.8 Practical Details and Other Notes
4.4.9 Fully Restrained Schematization of Column Base Detail
4.4.10 Example of Base Plate Design According to Eurocode
  4.4.10.1 Uplift and Moment
  4.4.10.2 Shear
  4.4.10.3 Welding
  4.4.10.4 Joint Stiffness
  4.4.10.5 Comparison with AISC Method for SLU1
4.5 Chemical or Mechanical Anchor Bolts
4.6 Fin Plate/Shear Tab
   4.6.1 Choices and Possible Variants 1
     4.6.1.1 Pin Position
     4.6.1.2 Location of PlateWelded to Primary Member
     4.6.1.3 Notches (Copes) in Secondary Member
     4.6.1.4 Reinforcing BeamWeb
   4.6.2 Limit States to Be Considered
   4.6.3 Rotation Capacity
   4.6.4 Measures to Improve Ductility
   4.6.5 Measures to Improve Structural Integrity
   4.6.6 Design Example According to DIN
   4.6.6.1 Bolt Shear
   4.6.6.2 Bearing
   4.6.6.3 Block Shear
   4.6.6.4 Plate Resistance
   4.6.6.5 Beam Resistance
   4.6.6.6 Plate Buckling
   4.6.6.7 Local Check for Primary-BeamWeb
   4.6.6.8 Welding  
   4.6.6.9 Rotation Capacity
   4.6.6.10 Ductility
   4.6.6.11 Structural Integrity
4.7 Double-Bolted Simple Plate
   4.7.1 Rotation Capacity
   4.7.2 Ductility
   4.7.3 Structural Integrity
   4.7.4 Beam-to-Beam Example Designed According to Eurocode
      4.7.4.1 Bolt Shear
      4.7.4.2 Bearing
      4.7.4.3 Block Shear
      4.7.4.4 Plate Resistance
      4.7.4.5 Beam Resistance
      4.7.4.6 Plate Buckling
      4.7.4.7 Primary-BeamWeb Local Check
      4.7.4.8 Welding, Ductility, and Structural Integrity
4.8 Shear (“Flexible”) End Plate
    4.8.1 Variants and Rotation Capacity
    4.8.2 Limit States to be Considered
    4.8.3 Rotational Stiffness
    4.8.4 Ductility
    4.8.5 Structural Integrity
    4.8.6 Column-to-Beam Example Designed According to IS 800
      4.8.6.1 Bolt Resistance
      4.8.6.2 Rotation Capacity and Structural Integrity
      4.8.6.3 Bearing
      4.8.6.4 Block Shear
      4.8.6.5 Plate Check
      4.8.6.6 Beam Shear Check
      4.8.6.7 Column Resistance
      4.8.6.8 Welds
      4.8.6.9 Conclusion
4.9 Double-Angle Connection
   4.9.1 Variants
   4.9.2 Limit States to Be Considered
   4.9.3 Structural Integrity, Ductility, and Rotation Capacity
   4.9.4 Practical Advice
   4.9.5 Beam-to-Beam Example Designed According to AISC
4.10 Connections in Trusses
   4.10.1 Intermediate Connections for Compression Members
4.11 Horizontal End Plate Leaning on a Column
   4.11.1 Limit States to be Considered
4.12 Rigid End Plate
   4.12.1 ColumnWeb Panel Shear
   4.12.2 Lever Arm
   4.12.3 Stiffeners
   4.12.4 SupplementaryWeb Plate Check
   4.12.5 Check for Column Stiffeners in Compression Zone
   4.12.6 Check for Column Stiffeners in Tension Zone
   4.12.7 Check of Column Diagonal Stiffener for Panel Shear
   4.12.8 Shear Due to Vertical Forces
   4.12.9 Design with Haunches
   4.12.10 Beam-to-Beam Connections
    4.12.11 BS Provisions
    4.12.12 AISC Approach
    4.12.13 Limit States to Be Considered
    4.12.14 Rotational Stiffness
    4.12.15 Simplifying the Design
    4.12.16 Practical Advice
    4.12.17 Structural Integrity, Ductility, and Rotation Capacity
    4.12.18 Beam-to-Column End-Plate Design Example According to Eurocode
       4.12.18.1 Column FlangeThickness Check for Bolt Row 1
       4.12.18.2 ColumnWeb Tension Check for Bolt Row 1
       4.12.18.3 Beam End-Plate Thickness Check for Bolt Row 1
       4.12.18.4 BeamWeb Tension Check for Bolt Row 1
       4.12.18.5 Final Resistant Value for Bolt Row 1
       4.12.18.6 Column FlangeThickness Check for Bolt Row 2 Individually
       4.12.18.7 ColumnWeb Tension Check for Bolt Row 2 Individually
       4.12.18.8 Beam End-Plate Thickness Check for Bolt Row 2 Individually
       4.12.18.9 BeamWeb Tension Check for Bolt Row 2 Individually
       4.12.18.10 Column Flange Thickness Check for Bolt Row 2 in Group with Bolt Row 1
       4.12.18.11 ColumnWeb Tension Check for Bolt Row 2 in Group with Bolt Row 1
       4.12.18.12 Beam End-PlateThickness Check for Bolt Row 2 in Group with Bolt Row 1
       4.12.18.13 BeamWeb Tension Check for Bolt Row 2 in Group with Bolt Row 1
       4.12.18.14 Final Resistant Value for Bolt Row 2
       4.12.18.15 Vertical Shear
       4.12.18.16 Web Panel Shear
       4.12.18.17 ColumnWeb Resistance to Transverse Compression
       4.12.18.18 Stiffener Design
       4.12.18.19 Welds
       4.12.18.20 Rotational Stiffness
4.13 Splice
   4.13.1 Calculation Model and Limit States
   4.13.2 Structural Integrity, Ductility, and Rotation Capacity
   4.13.3 Column Splice Design Example According to AS 4100
      4.13.3.1 Flanges
      4.13.3.2 Web
      4.13.3.3 Conclusions and Final Considerations
      4.13.3.4 Possible Alternative
4.14 Brace Connections
   4.14.1 AISC Methods: UFM and KISS
     4.14.1.1 KISS Method
     4.14.1.2 Uniform Force Method
     4.14.1.3 UFM Variant 1
     4.14.1.4 UFM Variant 2
     4.14.1.5 UFM Variant 3
     4.14.1.6 UFM Adapted to Existing Connections
   4.14.2 Practical Recommendations
   4.14.3 Complex Brace Connection Example According to CSA S16
     4.14.3.1 Friction Connection for Brace
     4.14.3.2 Brace and Gusset Bearing
     4.14.3.3 Block Shear
     4.14.3.4 Channel Shear Lag
     4.14.3.5 Whitmore Section for Tension Resistance and Buckling of Gusset Plate
     4.14.3.6 UFM Forces
     4.14.3.7 Gusset-to-Column Shear Tab
     4.14.3.8 Gusset-to-BeamWeld
     4.14.3.9 Beam-to-Column Shear Tab
     4.14.3.10 Ductility and Structural Integrity
4.15 Seated Connection
4.16 Connections for Girts and Purlins
4.17 Welded Hollow-Section Joints
4.18 Connections in Composite (Steel–Concrete) Structures
4.19 Joints with Bolts andWeldsWorking in Parallel
4.20 Expansion Joints
4.21 Perfect Hinges
4.22 Rollers
4.23 Rivets
4.24 Seismic Connections
   4.24.1 Rigid End Plate
   4.24.2 Braces
   4.24.3 Eccentric Braces and “Links”
   4.24.4 Base Plate
References

5 Choosing the Type of Connection

5.1 Priority to Fabricator and Erector
5.2 Considerations of Pros and Cons of Some Types of Connections
5.3 Shop Organization
   5.3.1 Plates or Sheets
   5.3.2 Concept of “Handling” One Piece
5.4 Culture
References

6 Practical Notes on Fabrication

6.1 Design Standardizations
   6.1.1 Materials
   6.1.2 Thicknesses
   6.1.3 Bolt Diameters
6.2 Dimension of Bolt Holes
   6.2.1 Bolt Hole Clearance in Base Plates
6.3 Erection 256
   6.3.1 Structure Lability
   6.3.2 Erection Sequence and Clearances
   6.3.3 Bolt Spacing and Interferences
   6.3.4 Positioning and Supports
   6.3.5 Holes orWelded Plates for Handling and Lifting
6.4 Clearance Needed to Operate TighteningWrenches
   6.4.1 Double Angles in Connections
6.5 Bolt Spacing and Edge Distances
6.6 Root Radius Encroachment
6.7 Notches
6.8 Bolt Tightening and Pretensioning    
   6.8.1 CalibratedWrench
   6.8.2 Turn of the Nut
   6.8.3 Direct Tension Indicators
   6.8.4 Twist-Off Type Bolts
   6.8.5 HydraulicWrenches
   6.9.1 Tapered (Beveled)Washers
   6.9.2 Vibrations
6.10 Dimensions of Screws, Nuts, andWashers
   6.10.1 Depth of Bolt Heads and Nuts
   6.10.2 WasherWidth and Thickness
6.11 Reuse of Bolts
6.12 Bolt Classes
6.13 Shims
6.14 Galvanization
   6.14.1 Tubes
   6.14.2 PlateWelded over Profiles as Reinforcement
   6.14.3 Base Plates
6.15 Other Finishes After Fabrication
6.16 Camber
6.17 Grout in Base Plates
6.18 Graphical Representation of Bolts and Connections
6.19 FieldWelds
6.20 Skewed Joints
References

7 Connection Examples

Index