<p>Acknowledgments xxi</p> <p>List of Abbreviations xxiii</p> <p><b>1 Fundamental Concepts of Joints in Design of Steel Structures 1</b></p> <p>1.1 Pin Connections and Moment Resisting Connections 1</p> <p>1.1.1 Safety, Performance, and Costs 1</p> <p>1.1.2 Lateral Load Resisting System 2</p> <p>1.1.3 Pins and Fully Restrained Joints in the Analysis Model 7</p> <p>1.2 Plastic Hinge 8</p> <p>1.2.1 Base Plates 9</p> <p>1.2.2 Trusses 11</p> <p>References 12</p> <p><b>2 Fundamental Concepts of the Behavior of Steel Connections 13</b></p> <p>2.1 Joint Classifications 13</p> <p>2.2 Forces in the Calculation Model and for the Connection 14</p> <p>2.3 Actions Proportional to Stiffness 17</p> <p>2.4 Ductility 18</p> <p>2.5 Load Path 19</p> <p>2.6 Ignorance of the Load Path 20</p> <p>2.7 Additional Restraints 21</p> <p>2.8 Methods to Define Ultimate Limit States in Joints 21</p> <p>2.9 Bolt Resistance 22</p> <p>2.10 Yield Line 22</p> <p>2.11 Eccentric Joints 22</p> <p>2.12 Economy, Repetitiveness, and Simplicity 22</p> <p>2.13 Man-hours and MaterialWeight 23</p> <p>2.14 Diffusion Angles 23</p> <p>2.15 Bolt Pretensioning and Effects on Resistance 24</p> <p>2.15.1 Is Resistance Affected by Pretensioning? 24</p> <p>2.15.2 Is Pretensioning Necessary? 24</p> <p>2.15.3 Which PretensioningMethod Should Be Used? 25</p> <p>2.16 Transfer Forces 25</p> <p>2.17 Behavior of a Bolted Shear Connection 25</p> <p>2.18 Behavior of Bolted Joints Under Tension 27</p> <p>References 29</p> <p><b>3 Limit States for Connection Components 31</b></p> <p>3.1 Deformation Capacity (Rotation) and Stiffness 31</p> <p>3.1.1 Rotational Stiffness 32</p> <p>3.2 Inelastic Deformation due to Bolt Hole Clearance 33</p> <p>3.3 Bolt Shear Failure 34</p> <p>3.3.1 Threads Inside the Shear Plane 35</p> <p>3.3.2 Number of Shear Planes 37</p> <p>3.3.3 Packing Plates 37</p> <p>3.3.4 Long Joints 38</p> <p>3.3.5 Anchor Bolts 39</p> <p>3.3.6 Stiffness Coefficient 39</p> <p>3.4 Bolt Tension Failure 40</p> <p>3.4.1 Countersunk Bolts 41</p> <p>3.4.2 Stiffness Coefficient 41</p> <p>3.5 Bolt Failure in Combined Shear and Tension 42</p> <p>3.6 Slip-Resistant Bolted Connections 42</p> <p>3.6.1 Combined Shear and Tension 44</p> <p>3.7 Bolt Bearing and Bolt Tearing 44</p> <p>3.7.1 Countersunk Bolts 49</p> <p>3.7.2 Stiffness Coefficients 49</p> <p>3.8 Block Shear (or Block Tearing) 49</p> <p>3.9 Failure ofWelds 52</p> <p>3.9.1 Weld Calculation Procedures 54</p> <p>3.9.1.1 DirectionalMethod 54</p> <p>3.9.1.2 Simplified Method 57</p> <p>3.9.2 TackWelding (Intermittent FilletWelds) 58</p> <p>3.9.3 Eccentricity 58</p> <p>3.9.4 FilletWeld Groups 58</p> <p>3.9.5 Welding Methods 60</p> <p>3.9.6 Inspections 60</p> <p>3.9.6.1 Visual Testing 60</p> <p>3.9.6.2 Penetrant Testing 60</p> <p>3.9.6.3 Magnetic Particle Testing 60</p> <p>3.9.6.4 Radiographic Testing 60</p> <p>3.9.6.5 Ultrasonic Testing 61</p> <p>3.10 T-stub, Prying Action 61</p> <p>3.10.1 T-stub with Prying Action 62</p> <p>3.10.2 Possible Simplified Approach According to AISC 64</p> <p>3.10.3 Backing Plates 65</p> <p>3.10.4 Length Limit for Prying Forces and T-stub without Prying 66</p> <p>3.10.5 T-stub Design Procedure for Various “Components” According to Eurocode 67</p> <p>3.10.5.1 Column Flange 67</p> <p>3.10.5.2 End Plate 71</p> <p>3.10.5.3 Angle Flange Cleat 71</p> <p>3.10.6 T-stub Design Procedure for Various “Components” According to the “Green Book” 71</p> <p>3.10.6.1 𝓁eff for Equivalent T-stubs for Bolt Row Acting Alone 74</p> <p>3.10.6.2 𝓁eff to Consider for a Bolt Row Acting Alone 77</p> <p>3.10.6.3 𝓁eff to Consider for Bolt Rows Acting in Group 79</p> <p>3.10.6.4 Examples of 𝓁eff for Bolts in a Group 80</p> <p>3.10.7 T-stub for Bolts Outside the Beam Flanges 81</p> <p>3.10.8 Stiffness Coefficient 81</p> <p>3.11 Punching 82</p> <p>3.12 Equivalent Systems 82</p> <p>3.13 Web Panel Shear 82</p> <p>3.13.1 Stiffness Coefficient 84</p> <p>3.14 Web in Transverse Compression 84</p> <p>3.14.1 Transformation Parameter 𝛽 86</p> <p>3.14.2 Formulas for Other Local Buckling Limit States 87</p> <p>3.14.3 Stiffness Coefficient 88</p> <p>3.14.4 T-stub in Compression 88</p> <p>3.15 Web in Transverse Tension 88</p> <p>3.15.1 Stiffness Coefficient 89</p> <p>3.16 Flange andWeb in Compression 89</p> <p>3.17 BeamWeb in Tension 89</p> <p>3.18 Plate Resistance 90</p> <p>3.18.1 Material Properties 90</p> <p>3.18.2 Tension 90</p> <p>3.18.2.1 Staggered Bolts 92</p> <p>3.18.3 Compression 92</p> <p>3.18.4 Shear 92</p> <p>3.18.5 Bending 93</p> <p>3.18.6 Design for Combined Forces 93</p> <p>3.18.7 Whitmore Section 93</p> <p>3.19 Reduced Section of Connected Profiles 93</p> <p>3.19.1 Shear Lag 95</p> <p>3.20 Local Capacity 99</p> <p>3.21 Buckling of Connecting Plates 100</p> <p>3.21.1 Gusset Plate Buckling 100</p> <p>3.21.2 Fin Plate (Shear Tab) Buckling 101</p> <p>3.22 Structural Integrity (and Tie Force) 103</p> <p>3.23 Ductility 105</p> <p>3.24 Plate Lamellar Tearing 106</p> <p>3.25 Other Limit States in Connections with Sheets and Cold-formed Steel Sections 108</p> <p>3.26 Fatigue 108</p> <p>3.27 Limit States of Other Materials in the Connection 109</p> <p>References 109</p> <p><b>4 Connection Types: Analysis and Calculation Examples 113</b></p> <p>4.1 Common Symbols 113</p> <p>4.1.1 Materials 113</p> <p>4.1.2 Design Forces 113</p> <p>4.1.3 Bolts 113</p> <p>4.1.4 Geometric Characteristics of Plates and Profiles 114</p> <p>4.2 Eccentrically Loaded Bolt Group: Eccentricity in the Plane of the Faying Surface 115</p> <p>4.2.1 Elastic Method 115</p> <p>4.2.1.1 Example of Eccentricity Calculated with Elastic Method 116</p> <p>4.2.2 Instantaneous Center-of-Rotation Method 118</p> <p>4.2.2.1 Example of Eccentricity Calculated with the Instantaneous Center-of-Rotation Method 119</p> <p>4.3 Eccentrically Loaded Bolt Group: Eccentricity Normal to the Plane of the Faying Surface 120</p> <p>4.3.1 Neutral Axis at Center of Gravity 121</p> <p>4.3.1.1 Example of Eccentricity Normal to Plane Calculated with Neutral Axis at Center-of-Gravity Method 122</p> <p>4.3.2 Neutral Axis Not at Center of Gravity 123</p> <p>4.3.2.1 Example of Eccentricity Normal to Plane Calculated with Neutral Axis not at Center-of-Gravity Method 124</p> <p>4.4 Base Plate with Cast Anchor Bolts 125</p> <p>4.4.1 Plate Thickness 125</p> <p>4.4.1.1 AISC Method 125</p> <p>4.4.1.2 Eurocode Method 130</p> <p>4.4.2 Contact Pressure 135</p> <p>4.4.2.1 AISC Method 135</p> <p>4.4.2.2 Eurocode Method 136</p> <p>4.4.3 Anchor Bolts in Tension 139</p> <p>4.4.3.1 AISC Method 139</p> <p>4.4.3.2 Eurocode Method 140</p> <p>4.4.3.3 Other Notes 141</p> <p>4.4.4 Welding 142</p> <p>4.4.5 Shear Resistance 142</p> <p>4.4.5.1 Friction 142</p> <p>4.4.5.2 Anchor Bolts in Shear 143</p> <p>4.4.5.3 Shear Lugs 144</p> <p>4.4.6 Rotational Stiffness 144</p> <p>4.4.7 Measures to Improve Ductility 145</p> <p>4.4.8 Practical Details and Other Notes 145</p> <p>4.4.9 Fully Restrained Schematization of Column Base Detail 148</p> <p>4.4.10 Example of Base Plate Design According to Eurocode 149</p> <p>4.4.10.1 Uplift and Moment 149</p> <p>4.4.10.2 Shear 152</p> <p>4.4.10.3 Welding 153</p> <p>4.4.10.4 Joint Stiffness 153</p> <p>4.4.10.5 Comparison with AISC Method for SLU1 153</p> <p>4.5 Chemical or Mechanical Anchor Bolts 153</p> <p>4.6 Fin Plate/Shear Tab 154</p> <p>4.6.1 Choices and Possible Variants 155</p> <p>4.6.1.1 Pin Position 155</p> <p>4.6.1.2 Location of PlateWelded to Primary Member 156</p> <p>4.6.1.3 Notches (Copes) in Secondary Member 157</p> <p>4.6.1.4 Reinforcing BeamWeb 158</p> <p>4.6.2 Limit States to Be Considered 161</p> <p>4.6.3 Rotation Capacity 161</p> <p>4.6.4 Measures to Improve Ductility 162</p> <p>4.6.5 Measures to Improve Structural Integrity 162</p> <p>4.6.6 Design Example According to DIN 162</p> <p>4.6.6.1 Bolt Shear 163</p> <p>4.6.6.2 Bearing 165</p> <p>4.6.6.3 Block Shear 166</p> <p>4.6.6.4 Plate Resistance 167</p> <p>4.6.6.5 Beam Resistance 167</p> <p>4.6.6.6 Plate Buckling 168</p> <p>4.6.6.7 Local Check for Primary-BeamWeb 168</p> <p>4.6.6.8 Welding 168</p> <p>4.6.6.9 Rotation Capacity 169</p> <p>4.6.6.10 Ductility 169</p> <p>4.6.6.11 Structural Integrity 169</p> <p>4.7 Double-Bolted Simple Plate 169</p> <p>4.7.1 Rotation Capacity 170</p> <p>4.7.2 Ductility 170</p> <p>4.7.3 Structural Integrity 171</p> <p>4.7.4 Beam-to-Beam Example Designed According to Eurocode 171</p> <p>4.7.4.1 Bolt Shear 172</p> <p>4.7.4.2 Bearing 173</p> <p>4.7.4.3 Block Shear 174</p> <p>4.7.4.4 Plate Resistance 174</p> <p>4.7.4.5 Beam Resistance 174</p> <p>4.7.4.6 Plate Buckling 174</p> <p>4.7.4.7 Primary-BeamWeb Local Check 174</p> <p>4.7.4.8 Welding, Ductility, and Structural Integrity 174</p> <p>4.8 Shear (“Flexible”) End Plate 175</p> <p>4.8.1 Variants and Rotation Capacity 175</p> <p>4.8.2 Limit States to be Considered 177</p> <p>4.8.3 Rotational Stiffness 177</p> <p>4.8.4 Ductility 178</p> <p>4.8.5 Structural Integrity 178</p> <p>4.8.6 Column-to-Beam Example Designed According to IS 800 178</p> <p>4.8.6.1 Bolt Resistance 179</p> <p>4.8.6.2 Rotation Capacity and Structural Integrity 179</p> <p>4.8.6.3 Bearing 180</p> <p>4.8.6.4 Block Shear 180</p> <p>4.8.6.5 Plate Check 180</p> <p>4.8.6.6 Beam Shear Check 180</p> <p>4.8.6.7 Column Resistance 180</p> <p>4.8.6.8 Welds 181</p> <p>4.8.6.9 Conclusion 181</p> <p>4.9 Double-Angle Connection 181</p> <p>4.9.1 Variants 183</p> <p>4.9.2 Limit States to Be Considered 183</p> <p>4.9.3 Structural Integrity, Ductility, and Rotation Capacity 183</p> <p>4.9.4 Practical Advice 183</p> <p>4.9.5 Beam-to-Beam Example Designed According to AISC 184</p> <p>4.10 Connections in Trusses 186</p> <p>4.10.1 Intermediate Connections for Compression Members 186</p> <p>4.11 Horizontal End Plate Leaning on a Column 188</p> <p>4.11.1 Limit States to be Considered 189</p> <p>4.12 Rigid End Plate 189</p> <p>4.12.1 ColumnWeb Panel Shear 191</p> <p>4.12.2 Lever Arm 191</p> <p>4.12.3 Stiffeners 192</p> <p>4.12.4 SupplementaryWeb Plate Check 193</p> <p>4.12.5 Check for Column Stiffeners in Compression Zone 193</p> <p>4.12.6 Check for Column Stiffeners in Tension Zone 195</p> <p>4.12.7 Check of Column Diagonal Stiffener for Panel Shear 196</p> <p>4.12.8 Shear Due to Vertical Forces 196</p> <p>4.12.9 Design with Haunches 196</p> <p>4.12.10 Beam-to-Beam Connections 196</p> <p>4.12.11 BS Provisions 197</p> <p>4.12.12 AISC Approach 197</p> <p>4.12.13 Limit States to Be Considered 199</p> <p>4.12.14 Rotational Stiffness 200</p> <p>4.12.15 Simplifying the Design 201</p> <p>4.12.16 Practical Advice 201</p> <p>4.12.17 Structural Integrity, Ductility, and Rotation Capacity 201</p> <p>4.12.18 Beam-to-Column End-Plate Design Example According to Eurocode 202</p> <p>4.12.18.1 Column FlangeThickness Check for Bolt Row 1 204</p> <p>4.12.18.2 ColumnWeb Tension Check for Bolt Row 1 204</p> <p>4.12.18.3 Beam End-Plate Thickness Check for Bolt Row 1 205</p> <p>4.12.18.4 BeamWeb Tension Check for Bolt Row 1 205</p> <p>4.12.18.5 Final Resistant Value for Bolt Row 1 205</p> <p>4.12.18.6 Column FlangeThickness Check for Bolt Row 2 Individually 205</p> <p>4.12.18.7 ColumnWeb Tension Check for Bolt Row 2 Individually 206</p> <p>4.12.18.8 Beam End-Plate Thickness Check for Bolt Row 2 Individually 206</p> <p>4.12.18.9 BeamWeb Tension Check for Bolt Row 2 Individually 206</p> <p>4.12.18.10 Column Flange Thickness Check for Bolt Row 2 in Group with Bolt Row 1 207</p> <p>4.12.18.11 ColumnWeb Tension Check for Bolt Row 2 in Group with Bolt Row 1 207</p> <p>4.12.18.12 Beam End-PlateThickness Check for Bolt Row 2 in Group with Bolt Row 1 207</p> <p>4.12.18.13 BeamWeb Tension Check for Bolt Row 2 in Group with Bolt Row 1 207</p> <p>4.12.18.14 Final Resistant Value for Bolt Row 2 208</p> <p>4.12.18.15 Vertical Shear 208</p> <p>4.12.18.16 Web Panel Shear 209</p> <p>4.12.18.17 ColumnWeb Resistance to Transverse Compression 209</p> <p>4.12.18.18 Stiffener Design 210</p> <p>4.12.18.19 Welds 210</p> <p>4.12.18.20 Rotational Stiffness 210</p> <p>4.13 Splice 212</p> <p>4.13.1 Calculation Model and Limit States 213</p> <p>4.13.2 Structural Integrity, Ductility, and Rotation Capacity 215</p> <p>4.13.3 Column Splice Design Example According to AS 4100 215</p> <p>4.13.3.1 Flanges 216</p> <p>4.13.3.2 Web 217</p> <p>4.13.3.3 Conclusions and Final Considerations 217</p> <p>4.13.3.4 Possible Alternative 217</p> <p>4.14 Brace Connections 217</p> <p>4.14.1 AISC Methods: UFM and KISS 220</p> <p>4.14.1.1 KISS Method 222</p> <p>4.14.1.2 Uniform Force Method 222</p> <p>4.14.1.3 UFM Variant 1 223</p> <p>4.14.1.4 UFM Variant 2 224</p> <p>4.14.1.5 UFM Variant 3 225</p> <p>4.14.1.6 UFM Adapted to Existing Connections 226</p> <p>4.14.2 Practical Recommendations 227</p> <p>4.14.3 Complex Brace Connection Example According to CSA S16 227</p> <p>4.14.3.1 Friction Connection for Brace 227</p> <p>4.14.3.2 Brace and Gusset Bearing 228</p> <p>4.14.3.3 Block Shear 228</p> <p>4.14.3.4 Channel Shear Lag 229</p> <p>4.14.3.5 Whitmore Section for Tension Resistance and Buckling of Gusset Plate 229</p> <p>4.14.3.6 UFM Forces 229</p> <p>4.14.3.7 Gusset-to-Column Shear Tab 229</p> <p>4.14.3.8 Gusset-to-BeamWeld 229</p> <p>4.14.3.9 Beam-to-Column Shear Tab 229</p> <p>4.14.3.10 Ductility and Structural Integrity 230</p> <p>4.15 Seated Connection 230</p> <p>4.16 Connections for Girts and Purlins 233</p> <p>4.17 Welded Hollow-Section Joints 236</p> <p>4.18 Connections in Composite (Steel–Concrete) Structures 236</p> <p>4.19 Joints with Bolts andWeldsWorking in Parallel 236</p> <p>4.20 Expansion Joints 237</p> <p>4.21 Perfect Hinges 238</p> <p>4.22 Rollers 239</p> <p>4.23 Rivets 240</p> <p>4.24 Seismic Connections 241</p> <p>4.24.1 Rigid End Plate 242</p> <p>4.24.2 Braces 243</p> <p>4.24.3 Eccentric Braces and “Links” 244</p> <p>4.24.4 Base Plate 244</p> <p>References 246</p> <p><b>5 Choosing the Type of Connection 249</b></p> <p>5.1 Priority to Fabricator and Erector 249</p> <p>5.2 Considerations of Pros and Cons of Some Types of Connections 249</p> <p>5.3 Shop Organization 250</p> <p>5.3.1 Plates or Sheets 250</p> <p>5.3.2 Concept of “Handling” One Piece 250</p> <p>5.4 Culture 252</p> <p>References 252</p> <p><b>6 Practical Notes on Fabrication 253</b></p> <p>6.1 Design Standardizations 253</p> <p>6.1.1 Materials 253</p> <p>6.1.2 Thicknesses 253</p> <p>6.1.3 Bolt Diameters 253</p> <p>6.2 Dimension of Bolt Holes 254</p> <p>6.2.1 Bolt Hole Clearance in Base Plates 255</p> <p>6.3 Erection 256</p> <p>6.3.1 Structure Lability 256</p> <p>6.3.2 Erection Sequence and Clearances 256</p> <p>6.3.3 Bolt Spacing and Interferences 257</p> <p>6.3.4 Positioning and Supports 257</p> <p>6.3.5 Holes orWelded Plates for Handling and Lifting 258</p> <p>6.4 Clearance Needed to Operate TighteningWrenches 258</p> <p>6.4.1 Double Angles in Connections 259</p> <p>6.5 Bolt Spacing and Edge Distances 260</p> <p>6.6 Root Radius Encroachment 260</p> <p>6.7 Notches 264</p> <p>6.8 Bolt Tightening and Pretensioning 265</p> <p>6.8.1 CalibratedWrench 266</p> <p>6.8.2 Turn of the Nut 266</p> <p>6.8.3 Direct Tension Indicators 270</p> <p>6.8.4 Twist-Off Type Bolts 271</p> <p>6.8.5 HydraulicWrenches 273</p> <p>6.9.1 Tapered (Beveled)Washers 275</p> <p>6.9.2 Vibrations 277</p> <p>6.10 Dimensions of Screws, Nuts, andWashers 277</p> <p>6.10.1 Depth of Bolt Heads and Nuts 277</p> <p>6.10.2 WasherWidth and Thickness 277</p> <p>6.11 Reuse of Bolts 278</p> <p>6.12 Bolt Classes 279</p> <p>6.13 Shims 280</p> <p>6.14 Galvanization 281</p> <p>6.14.1 Tubes 281</p> <p>6.14.2 PlateWelded over Profiles as Reinforcement 281</p> <p>6.14.3 Base Plates 282</p> <p>6.15 Other Finishes After Fabrication 282</p> <p>6.16 Camber 283</p> <p>6.17 Grout in Base Plates 284</p> <p>6.18 Graphical Representation of Bolts and Connections 286</p> <p>6.19 FieldWelds 287</p> <p>6.20 Skewed Joints 287</p> <p>References 291</p> <p><b>7 Connection Examples 293</b></p> <p>Index 355</p>