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<br /> 11.2 Withdrawal Design Values
<br /> 11.2.1 Lag Screws 11.2.1.2 When lag screws are loaded in withdrawal
<br /> from end grain, nominal withdrawal design values, W,
<br /> 11.2.1.1 The withdrawal design values, in lbs./in. of shall be multiplied by the end grain factor, Ces = 0.75.
<br /> penetration, for a single lag screw inserted in side grain, 11.2.1.3 When lag screws are loaded in withdrawal,
<br /> with the lag screw axis perpendicular to the wood fibers, the allowable tensile strength of the lag screw at the net
<br /> shall be determined from Table 11.2A or Equation 11,2-1, (root) section shall not be exceeded(see 10.2.3).
<br /> within the range of specific gravities and screw diameters
<br /> given in Table 11.2A.Tabulated nominal design values,W,
<br /> shall be multiplied by all applicable adjustment factors(see
<br /> Table 10.3.1)to obtain allowable design values,W'.
<br /> W=1800G312D3/4 (11.2-1)
<br /> Table 11.2A Lag Screw Withdrawal Design Values (W)1
<br /> Tabulated withdrawal design values(W)are in pounds per inch of thread penetration into side grain of main member.
<br /> Length of thread penetration in main member shall not include the length of the tapered tip(see Appendix L).
<br /> Specific
<br /> Gravity Lag Screw Unthreaded Shank Diameter,D
<br /> G 1/4" 5/16" 3/8" j 7/16" 1/2" 5/8" 3/4" 7/8" 1 1" 1-1/8" 't 1-1/4"
<br /> 0.73 397 469 538 604 668 789 905 1016 1123 1226 1327
<br /> :b 7t. 381 45Q' t'516 579 640 7., 757 • :868 974'. 101.7 1'116 -1273 •:..
<br /> 0.68 357 422 484 543 600 709 813 913 1009 1103 1193
<br /> 0.6.7." , ;:� 349 .. : 4 3 .-'473::.,::: 531 :`. _ 587 ; 654 :': 796 ` ' 893' ::987 1078 •'.:1167 `.,
<br /> 0.58 281 332 381 428 473 559 641 719 795 869 940
<br /> 0.55 260;: ;3[l7 _ ..352 ,: 395 437 51.6 :592 664'_- 734 :$02 S68
<br /> 0.51 232 274 314 353 390 461 528 593 656 716 775
<br /> 0�6fl . , 25.`, -05011.. `'3 $ i- 3.412 378. 447,, ;513 . 576,' :636 ::695 _. 752
<br /> 1 0.49 218 258 296 r 332 367 434 498 559 617 674 730
<br /> 947:. :, `205 ' 24r.. } . Z78 . ' 31,2 3.45. 49.8. 467 > : 525 ,
<br /> s$o 634 6sf :r;
<br /> `' 0.46 199 235 269 302 I 334 395 453 508 562 613 664
<br /> 1 . <: 0 4 ' 186 ;:. 0" ' :f:252 v'283- t 312. :369 ,::423 475:' `525 574.. " 621..
<br /> 0.43 179 212 243 273 302 357 409 459 508 554 600
<br /> 6 . "' : 1'73 > s; 5 x 23S -.264 -29.1: :344 ;395 443'' 49.0.. :{-535 . 579,. ,
<br /> 0.41 167 198 226 254 281 332 381 428 473 516 559
<br /> .&.4,4: 61_, 1$0 2 8 . :,. 2'71-' , 32Q , . :367 412 455 497. 538` ;_
<br /> 039 155 183 210 236 261 308 353 397 438 479 518
<br /> ' 038- ,` 149 :,I76 .202 ,' `22:r. 251 . 296 340 38I . 422 ;.461 ' ,`''49„$: -.
<br /> 0.37 143 169 194 218 241 285 326 367 405 443 479
<br /> 036`;!-A 137, ;h' 163zcg.
<br /> . `�{1;86°. ;r2f39 ": ,r23;1 273.,; , 4313 352 3 91J ,'4.25 460
<br /> 0.35 132 156 179 200 222 262 300 337 373 407 441
<br /> 1y .0 3,1:;.-.�L {i1t10::.:` d440 s .`r�.149 16;r: :, `,.185`' 21:8.'_,:`�`250 _ .281;. . ;'3,11 :{:.339,_- ..z3;67;`
<br /> 1.Tabulated withdrawal design values(W)for lag screw connections shall be multiplied by all applicable adjustment factors(see Table 10.3.1).
<br /> I
<br /> AMERICAN WOOD COUNCIL
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