Example 3.1A Beginners Guide to the Steel Construction Manuallast modified: 11 Aug 2007Example Problem 3.1by: TBQGivenA tension member made of ASTM A36 Steel with the dimensions shown and is 3/4" thick.Fy =36ksi (SCM Table 2-4, pg 2-40)Fu =58ksi (SCM Table 2-4, pg 2-40)L =5ftb =10inLoads:Dead140kips =82.4%of total loadtpl =0.75inLive30kips =17.6%of total loaddb =0.75inWanted:Determine if this member is a feasible solution for the given loads.Solution:Results Summary:Computations followTable of Result RatiosLimit StateLRFDASDSlenderness0.9240.924Tensile Yielding0.8891.051For ASD need to increase cross sectional areaTensile Rupture0.8030.947Block Shear0.9131.077For ASD either thicken plate or space bolts widerBolt Bearing0.3780.446Member is adequate for LRFD.Member is inadequate for ASD.Table of CapacitiesLimit StatePuPa(k)(k)SlendernessN/AN/ATensile Yielding243162Tensile Rupture269179Block Shear237158Bolt Bearing572381ASCE 7 Load Combinations:PuPsLRFD LC2216kipsASD LC2170kipsSection PropertiesImin =0.352in^4Ag =7.5in^2rmin =0.217inSlenderness (Section D1)L/r =277(L/r)/300 =0.924Limit State StatisfiedTensile Yielding (Section D2)Pn =270kipsLRFDASDft =0.9Wt =1.67ft Pn =243kipsPn / Wt =162kipsPu / ft Pn =0.889Limit State StatisfiedPa / (Pn / Wt )=1.051No GoodTensile Rupture (Section D2)Net Area Determinationfailure path #2sgs2/4gTotal widthtplArea(in)(in)(in)(in)(in2)width segment 10.0002.0000.0002.0000.7501.500width segment 20.0006.0000.0006.0000.7504.500width segment 30.0002.0000.0002.0000.7501.500hole 1-0.8750.750-0.656hole 3-0.8750.750-0.656Net Area6.188failure path #3sgs2/4gTotal widthtplArea(in)(in)(in)(in)(in2)width segment 10.0002.0000.0002.0000.7501.500width segment 23.0003.0000.7503.7500.7502.813width segment 33.0003.0000.7503.7500.7502.813width segment 40.0002.0000.0002.0000.7501.500hole 1-0.8750.750-0.656hole 2-0.8750.750-0.656hole 3-0.8750.750-0.656Net Area6.656Controlling An =6.188in2U =1.000Ae =6.188in2Pn =358.9kipsLRFDASDft =0.75Wt =2ft Pn =269kipsPn / Wt =179kipsPu / ft Pn =0.803Limit State StatisfiedPs / (Pn / Wt )=0.947Limit State StatisfiedBlock Shear (Section J4.3)tpl =0.75indb =0.75inFailure Path #1gross pathnumbernet pathlengthholes/pathlength# pathsArea(in)(in)(in^2)Agv10.5000.00010.5002.00015.750Anv10.5003.5007.4382.00011.156Ant6.0001.0005.1251.0003.844Ubs1.0ShearShearUseFractureYield(k)(k)(k)Rn611.2563.1563.1Failure Path #2gross pathnumbernet pathlengthholes/pathlength# pathsArea(in)(in)(in^2)Agv10.5000.00010.5001.0007.875Anv10.5003.5007.4381.0005.578Ant8.0001.5006.6881.0005.016Ubs0.5ShearShearUseFractureYield(k)(k)(k)Rn339.6315.6315.6Controlling Rn =315.6kLRFDASDft =0.75Wt =2ft Rn =237kipsRn / Wt =158kipsPu / ft Pn =0.913Limit State StatisfiedPa / (Pn / Wt )=1.077No GoodBolt Bearing (J3.10)Deformation at the bolt hole is not a design considerationUse Equation J3-6btpl =0.75inLc =1.0625indb =0.75innum bolts =11bolts/connectionTearBearingUseUseOutDeformation(k/bolt)(k/bolt)(k/bolt)(k)Fu factor1.53.0Rn69.397.969.3762.6LRFDASDft =0.75Wt =2ft Rn =572kipsRn / Wt =381kipsPu / ft Pn =0.378Limit State StatisfiedPa / (Pn / Wt )=0.446Limit State StatisfiedComparison of LRFD Capacity to ASD CapacityControlling fPn =237kControlling Pn / Wt =158kLRFDASD% DLLFPs,eqLFPs,eq(k)(k)0%1.601481.0015825%1.501581.0015850%1.401691.0015875%1.301821.00158100%1.201971.00158

Example 3.1

LRFDASD% of Total Load that is Dead LoadService Level Capacity (k)Service Level Capacity

Example 3.2A Beginners Guide to the Steel Construction Manuallast modified: 11 Aug 2007Example Problem 3.2by: TBQGivenA pair of bolted splice plates is used to connect two WT sections together in tension.See Sheet S3 of the drawing set.Fy =50ksi (SCM Table 2-4, pg 2-40)Fu =70ksi (SCM Table 2-4, pg 2-40)L =2ftb =9inLoads:Dead40.0%of Total Service Loadtpl =0.500inWind60.0%of Total Service Loaddb =0.875inWanted:Determine the maximum force that the pair of splice plates can transfer between the WTs.Solution:Results Summary:Computations followTable of CapacitiesLRFDASDLimit StatefPnPn/WeqivPn/WeqivPn/WPn/W(k/plate)(k/plate)(k/pair)(k/plate)(k/pair)SlendernessN/AN/AN/AN/AN/ATensile Yielding202.5140.6281.3134.7269.5Tensile Rupture167.3116.2232.4111.6223.1