DESIGN OF FLUST-EXTENDED END PLATE CONNECTIONPROJECT : KING SAUD UNIVERSITY

DATE: 7/23/2010 Prep. By: S.S. Check. : MB Cert. : MB

BUILDING: B#24- GRAND FOYERMembers Joint CASE NO CASE OF LOADING DESCRIPTION

1001 500 8 D + L

DESIGN NOTES AND ASSUMPTIONS :-All Dimensions in mm ,Forces in ton and stresses t/cm2.-This procedure is deigned for bearing type connections only.-The primary assumption in this approach is that the end plate must substantially yield to produce prying forces in the bolts.Conversely,if the plate is strong enough,no prying action occurs and the bolts are loaded in direct tensionThis simplified assumption allows the designer to directly optimize either the bolt diameter or end-plate thicknessas desired.-The threshold when prying action begins to take place in the bolts at 90% of the full strength of the plate or 0.9MplIf the applied load is less than this value, the end plate behaves as a thick plate and prying action can be neglected in the bolts.Once the applied moment crosses the threshold of 0.9Mpl,the plate can be approximated as a thin plateand maximum prying is incorporated in the bolt analysis.-Intermediate plate behaviour is a transition from Thick to Thin behaviour and considered as a thin behaviour during the analysis.-The factored axial load will be converted into an equivalent moment that will be added to the factored connection moment for axial tension.-The width of end plate ,Which is effective in resisting the applied beam moment shall not be taken greater thanthan the beam flange width plus 1 inch in the calculations.-The beam flange to end plate weld can be designed for the required moment strength but not less than 60% of the specified minimum yield strength of the connected beam flange.-When the full design strength is not required, the beam web to end plate welds should be designed to develop60% of the minimum specified yield strength of the beam web.-Stitch bolts are sometimes used between the tension and compression flange end plate bolts especially in deep connections. The purpose of these bolts is to reduce plate separation caused by welding distortions.Because stitch bolts are located near center of gravity of the member,Contribution to connection strength is small and is neglected-The purpose is to design connections Type(FR) or Type"1" which is fully restrained moment connections-Type(1) or "FR" connections are traditionally required to carry and end moment greater than or equal to 90%of the full fixity end moment of the beam and not rotate more than 10% of the simple span rotation.-This procedure is based on Yield line technique to determine end plate thickness and to predict the tension forcesConsidering the prying actions.-Yield line are the continous formation of the plastic hinges along a straight or curved lines.-Thick plate behaviour is taken place when plastic hinges is not formed in the split-tee flange and the prying force value is equal to "zero".-Thin plate behaviour is taken place when plastic hinges is formed in the split-tee flange and the prying forcevalue is not equal to "zero".-All loads and internal forces comply with LRFD method (internal forces in ASD Could be muliplied by 1.5).-Flush End plate connections are typically used for light loads or near moment inflection point.-All Shear Forces assumed to be resisted by compression bolts-Bolts in tension may be tightened to 70% of the bolt tensile strength or could be snug tightened (for Bolts A325 Only)-This spreadsheet is designed to check the connection strength for the following limit states :

-Connection Strength Based on End plate Yielding.-Connection Strength Based on bolt rupture without prying action.-Connection Strength Based on bolt fracture w/prying action.

-Effect of axial forces will be neglected incase the axial force is compression.

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NOTATIONS

rotation at ultimate moment to the outer bolt centerline in extended end plate connection to 10% of simple span rotation

to the farthest inner load-carrying bolt line.

to the second farthest inner load-carrying bolt line.

to the third farthest inner load-carrying bolt line.

bolt centerline to the innermost flange to the near face of the beam tension flangeyield line

of the beam tension flange

centerline to the inner face of the the face of the stiffener in four-bolt flush connection with stiffener in four-bolt flush connection stiffener between bolt rowswith stiffener inside bolt rows

the beam tension flangeexterior bolt centerline =pext-pf,o

capacity ,proof load = Ab x Ft bolt fracture with no prying action

plate configurations = [tp2*Fpy*(0.85bp/2+0.8w') + πdb3 Ft/8]/(4Pf,i)

centerline of "n" boltfor interior bolts

exterior boltsstate of bolt fracture with prying action.

Table J3.1,AISC(2000) or if if snugg tight,recommended the edge of the hole and the edge of the percentage of Table J3.1 based on bolt diameteradjacent hole.

major axis of the beamA)DESIGN INPUT

Type of Connection Extended.End.Plate Type of Bolt A325NBolts Arrangement E.4 Type OF Tightening Snug TighteningStiff. Arrangement Unstiffened tf = 10.00 MM

Tension flange weld Fillet Weld bf = 200.00 MM4.09 t/cm2 tw = 13.00 MM

10 MM 19.05 MM203 MM g = 76.20 MM

h = 600 MM 673.00 MM3.52 t/cm2 565.00 MM

5 t/cm244.45 MM 600.00 MM63.5 MM 500.00 MM65 MM 34.93 MM

31.75 MM 20.00 MM127 MM Mu = 2018 ton.cm

No.Of bolt rows in Compn = 2 Tu = 0 tonNo.Of bolt cols in Compn = 2 18 MM

Lp = 60 MM 4 MM

ɣr-Load Factor to limit connection h0-distance from the compression side of the beam

h1-distance from the compression side of the beamdb-nominal bolt diametertp-End Plate Thickness h2-distance from the compression side of the beambp-End Plate Widthh-Total Beam depth h3-distance from the compression side of the beamg-Bolt GageY-Yield line mechanism parameter h-Total depth of the beamFyp-End plate material yield stress Mpl-Connection strength for limit state of end plate yieldings(1/2√bp*g)-Distance from the innermost Pf,i-distance from the bolt centerline adjacent to beam tension

Pf,O-distance from the outer bolt centerline to the outer face Pb-distance from bolt CL to bolt CLPs,i-distance from the first interior bolt Ps,o-distance from the outer bolt centerline to the outer

Pext-End-plate extension beyond the exterior face of de-End-plate extension beyond the

Ft-Tensile strength of boltstf-Beam Flange Thickness Ab-Nominal Bolt areaPt-Bolt material Ultimate tensile load Mnp-Connection strength for the limit state of

W'-bp/2-(db+1/16) ai-Distance from the interior bolt centerline to theFi'-Flange force per bolt at the thin plate prying force = 3.682 (tp / db)^3 - 0.085limit when calculating Qmax,I for end ao-Distance from the exterior bolt centerline to the

prying force = Min of (3.682 (tp / db)^3 - 0.085 , Pext-Pf,o )

d(0,1,2)-Distance from the Compression flange centerline to theQmax,i-Maximum Possible Prying force

Qmax,o-Maximum Possible Prying force forMq-Connection strength for the limit

Tb-Specified pretension load in high strength boltsLc-Clear distance in direction of force between

Lp-Spacing between bolt rows centerlines in compn zonebf-Width of the flange beam tw-Thickness OF the beam webIwxx-Welds moment of inertia about the Mnw-Connection Strength Based on Welding to the end plate

FExx =

tp = db =bp =

h0 =Fyp = h1 =Fup =

Pf or Pf,i = h2 =Pf,o = h3 =Pb = Ps,o =Ps,i = Ps =

Pext =

Sf =Sw =

B)DESIGN PARAMATERS1 668.00 MM 6.33 t/cm2

s = 62.19 MM 560.00 MM 2.85 CM244.45 MM 0.00 MM Y = 481.9 CM63.5 MM 0.00 MM w' = 8.05 CM1.14 CM 18.04 ton 6.05 ton1.14 CM 3.95 ton 6.14 ton2.76 ton Tb = 6.31 ton Mu = 2018.00 ton.cm

Iwxx = 124501 cm4 Lc = 38.95 MM Fnv = 3.38 t/cm2Connection Behaviour Thin Plate Behaviour(W/Prying action)

C)LIMITS OF APPLICABILITY1) 25 64 OK2) 64 130 OK3) 70 ≥ g ≥ 178 OK4) 400 ≥ h ≥ 610 OK5) 152 260 OK6) 9.5 26 OK

D)Calculation of Connection Strength

0.91696.18 t.cm

1527 t.cm

ɸ = 0.75

4431.10 t.cm2.61

3323 t.cm

a)Case of Extended End Plate Connection b)Case of Flush End Plate Connectionɸ = 0.75 ɸ = 0.75Mq = Mq =

[ 2(pt-Qmax)(d1+d2) ][ 2Tb(d1+d2) ]

Max

Max

ɸMq = 2200 t.cm Thin Plate Behaviour(W/Prying action)

iv) Limit state based on shear strength of boltsɸ = 0.75ɸRn = ɸ * Fnv * Ab = 29 ton(AISC 360-05 J3-1)iiv) Limit state based on Bearing strength at bolt holesɸ = 0.75ɸRn = (AISC 360-05 J3-6a)ɸ*1.2*Lc*t*Fu*n = 70.11 tonɸ*2.4*d*t*Fup*n = 68.58 ton

ɸRn = 69 toniv) Limit state based on welding to end plateɸ = 0.75ɸFw = ɸ * 0.6 * FExx = 1.84 t/cm2

7416 t.cm

Connection StrengthMu(t.cm) Qu(ton) Mnw(t.cm)

ɣr = d0 = Ft =d1 = Ab =

pf,i = d2 =de = d3 =ai = Pt = Qmax,i =

ao = Fi' = Qmax,o =

Fo' =

≥ Pf ≥ ≥ Pb ≥

≥ bp ≥ ≥ tf ≥

i)Limit state of End-Plate Yielding(Mpl)ɸb =Mpl = Fpy * tp2 * Y =

ɸbMpl/ɣr =ii) Limit state of Bolt Rupture(Mnp) without prying action.

Mnp = [ 2 Pt (Σdn) ] = Mnp/ Mpl =

ɸMnp =iii) Limit state of Bolt Rupture(Mq) w/prying action

[2*(Pt-Qmax,o)d0 + 2(Pt-Qmax,i) (d1 + d3) + 2Tb*d2 ] [2*(Pt-Qmax,o)d0 + 2Tb (d1+d2+d3) ] [2*(Pt-Qmax,o)*(d1+d3) + 2Tb (d0+d2) ] [2Tb (d0+d1+d2+d3) ]

ɸ*1.2*Lc*t*Fup*n ≤ ɸ*2.4*d*t*Fup*n

ɸMnw = ɸFw * Iwxx / yw

ɸMnw =

1527 29 7416