Job No. Sheet 1 of 8 Rev B. Made by IR Date Aug Checked by FH/NB Date Oct Revised by MEB Date April 2006

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1 Job o. Sheet 1 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 DESG EXPLE 5 WELDED JOT The joint configurtion nd its loding re shon in the figure belo. oting tht there re to identicl plne fillet eld joints of constnt throt size shring the pplied loding, the required throt size for the elds shll be determined. Right ngle (equl leg) elds ill be used throughout. illet elds : throt size throughout C 175 z xis 300 x e z = 300 k y = 30 k e = Elevtion y xis C n C n 1 x xis 175 C : centre of grvity of eld joint 300 z Pln x = - 0 k y xis for joint n y = 30 k y xis for joint n 1 teril properties Use mteril grde ,% proof stress = 0 /mm nd the tensile strength is = 530 /mm Tble 3.1 Tke f y s the 0,% proof stress = 0 /mm nd f u = 530 /mm Section 3..4 E = /mm nd G = /mm Section 3..4 t is ssumed tht the yield nd ultimte tensile strength of the eld eeed those of the Section.4.1 prent metl. Prtil sfety fctor Prtil sfety fctor on eld resistnce : γ = 1,5 Tble.1 β = 1,0 Section.4. The need to include reduction fctor on the eld resistnce to ccount for its length ill be exmined. nlysis n elstic nlysis pproch is used here for designing the right-ngle equl-leg fillet eld for the lod cse indicted bove. n elstic nlysis of the elded joint leds to conservtive estimte of the joint resistnce. The co-ordintes of point (x c, y c, z c ) on the elded joint re tken ith reference to right hnd xis system ith n origin t the centre of grvity of the elded joint. (n the present cse the joint is tken to be in the y-z plne so tht x c = 0 throughout.) The min purpose of the elstic nlysis is to determine the induced design forces in the eld t the most severely loded point or points of the elded joint, often referred to s the criticl points. or the elded joint being exmined the criticl point cn be tken s being the point the frthest removed from the centre of grvity of the joint. E , cluse.5 135

2 Job o. Sheet of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 The vectors of the pplied force, its eccentricity nd the resulting moments cting on elded joint of generl form nd centre of grvity C cn be expressed s follos : pplied force = [, ], Ed x,ed y,ed, Eccentricity of the pplied force [ e, e e ], z,ed e = hich re the co-ordintes of the point of ppliction of the force vector, Ed pplied moments, Ed = e, Ed = e = e, Ed z,ed x,ed y,ed e e e y,ed z,ed x,ed liner elstic nlysis of the joint for generl lod cse leds to the folloing induced force components per unit length of eld t point ith co-ordintes (x c, y c,, z c ), here the throt size is denoted by : x,ed = x,ed,ed,ed y,ed x y,ed = c,ed,ed z,ed = z,ed,ed,ed n the bove expressions, the resisting sectionl throt re nd the inertis bout the principl xes of the elded joint re: = dl = i li for eld of stright segments of length l i nd throt size i, c c = ( y z ) dl c c = ( x z ) dl c c = ( x y ) dl s the throt size,, is constnt throughout the plne joint, one cn rite : = dl = li, Since x c = 0, 13

3 Job o. Sheet 3 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 ( y = c ) dl, = ( z c ) dl, = ( ) dl = Design pproches Section.4. Determine the required eld throt size t the criticl point. To different procedures re lloed for designing fillet elds: The first procedure is bsed on the simplified, nd more conservtive, design sher strength for fillet eld. The design sher force per unit length of eld t ny point of the joint is defined s the vector sum of the induced forces per unit length due to ll forces nd moments trnsmitted by the elded joint. This design sher force per unit length should not eeed the design resistnce per unit length hich is tken s the design sher strength multiplied by the throt size. This pproch ignores the throt plne orienttion to the direction of resultnt eld force per unit length. The second procedure is bsed on compring the bsic design strength of the eker prt joined to the pplied design eld stress in the eld throt determined by Von ises type of formul. This pproch is the most precise s it llos for the throt plne orienttion to the direction of resultnt eld force per unit length. 1. Simplified design sher strength of the eld The design resistnce check of the fillet eld is s follos: f,ed = u / 3 E , = = x,ed y,ed z,ed,rd f v,d cluse β γ Where: f v,d is the design sher strength of the eld,rd is the design (sher) resistnce per unit length of eld of throt size. or stinless steel β my be tke s 1.0 Section.4. When the design procedure requires tht suitble throt size be obtined, the design expression becomes :,Ed f v,d. Bsic design strength of the eld n this pproch one must check the Von ises type stress in the eld throt ginst the bsic design strength of the fillet eld mteril. n generl this requires tht the stresses in the eld throt, σ, τ nd τ be obtined, thus tking ccount of the orienttion of the plne of the throt re to the direction of the resultnt induced eld force per unit length. The design formul is s follos: f u Eq..1 σ 3( τ τ ) β γ t is lso required to check the norml stress seprtely: 0.9 f u σ γ 137 Eq.1b

4 Job o. Sheet 4 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 or the present cse of plne fillet eld joint ith right ngle (equl leg) elds this ltter check is not criticl. Hoever it my be so for prtil penetrtion elds in bevelled joints. nsted of hving to clculte the stresses (σ, τ nd τ ) in the eld throt the folloing design check expression my be used for y-z plne joints ith right ngle (equl leg) elds:, x,y,z, y, z, y f Sinθ Cosθ u βγ Cos θ, z Sin θ ote : The subscripts hve been shortened:,x for x,ed etc.,x,y Sinθ,x,z Cosθ n the bove expression the ngle θ is tht beteen the y xis nd the xis of the eld s shon in the folloing figure. ttched element,x Section 1-1 support ttched element 1 1,z z,y θ y ttched element illet eld xis θ,z z,y y,x ttched element support Section - The force components t the criticl point of the eld re determined in the ppendix to this design exmple. 1. Design using the simplified design sher strength pproch The design sher strength for the simplified design pproch is: f u 530 f v,d = = 45/mm E , γ ,5 3 Eq. 4.4 β The vlue of the resultnt induced force per unit length in eld throt of 1mm is : x, Ed y, Ed z, Ed =,Ed = = /mm The required throt size is therefore:,ed 145 = 5, 0 mm f 45 v,d 138

5 Job o. Sheet 5 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00. Design of the eld using the bsic design eld strength pproch The bsic design strength of the eld mteril is tken s follos: 0.9 f γ u = = 381, /mm Eq..1b 1,5 Where f u is the ultimte tensile strength of the eker prt joined t the point (), here the ngle θ is 0, the design check expression becomes: x, Ed 3 y, Ed z, Ed The required throt size is therefore: x,ed z,ed f γ u ( 43 ) 3 (747 ) (9 ) ( 43 ) (9 ) = 4,7 381, dopt 5 mm throt size nd ssume tht the eld is full size over its entire length. mm ote : reduction fctor is required for splice joints hen the effective length of fillet eld is greter thn 150. The reduction fctor ould seem to be less relevnt for the present type of joint. evertheless by considering, sfely, the full length of the elded joint nd throt size of 5 mm one obtins: β LW.1 = 1, 0,L j /(150) = 1, 0,(00) /(150 5) = 1, 04 Tke β LW.1 = 1,0 t is concluded tht the use of reduction fctor on the design strength of the eld is not required. E , Eq

6 Job o. Sheet of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 ppendix Clcultion of the force components t the criticl point of the eld Geometric properties of the elded joint There re to similr joints, one on ech side of the column, resisting the pplied lods. Only one of the joints needs to be exmined. t is plced in the y-z plne. Throt re nd positions of the centre of grvity nd the criticl point Throt re (resisting section) of ech of the joints mde up of stright segments of length L i nd constnt throt size is, for ech 1mm of throt size: ds =, i L, i = = = Li = ( ) = 00 mm /m Distnce of the centre of grvity from the verticl side (prllel to the z xis) of the joint of constnt throt size : yi (, i / ) yili (87,5 175) (0 50) y = = = 51mm / L 00, i i 51 y c = = 14 e Lod point 15 r c, e z c = -15 C y-y 15 d 175 z-z The co-ordintes of the position of the criticl point of the joint, the point (), reltive to the principl xes through centre of grvity (C) re : y c = ( ) = 14 mm z c = 15 mm ote: the point (d) might lso be chosen s potentil criticl point, for hich : y cd = ( ) = 14 mm z cd = 15 mm Hoever, for the lod cse considered it is evident tht the point () is the most criticl. nertis of the joint resisting section or ech of the joints, for ech 1mm of throt size : = z ds 3 c = /1 =,77 10 mm4 /mm 140

7 Job o. Sheet 7 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 = 3 c = /1 175 (87,5 51) y ds = 10 mm4 /mm or the torsion moment the relevnt inerti, per joint, is : = r ds c = y ds c ds = So tht = (,77,01) 10 = 8,78 10 mm 4 /mm pplied forces nd moments t is ssumed tht pplied lods nd moments re shred eqully by the to joints. The pplied xil nd sher force components per joint re: x, Ed = 0 30 = 10 k, y, Ed = = 15 k, z, Ed = 300 = 150 k pplied moments re clculted using the pplied force components nd their eccentricities. The eccentricities, i.e. the co-ordintes of the effective lod point, re : e = 0 s the effective lod point is tken to be in the y-z plne of the joint, e = ( ) = 34 mm, e = 140 mm The pplied moments, per joint, re then;,ed = e z,ed e y,ed = ( 34) ( 150) ( 140) ( 15) = 50, 7 km,ed = e x,ed e z,ed = ( 140) ( 10) (0) ( 150) = 1, 4 km,ed = e e = (0) ( 15) ( 34) ( 10) = 3, 4 km y,ed x,ed orce components t the criticl point of the eld or the y-z plne joint, the force components per unit length of eld t the point () re: x,ed = y,ed = z,ed = z y x,ed c,ed c,ed / / / / / y,ed,ed /,Ed,Ed / 141

8 Job o. Sheet 8 of 8 Rev B 10, Route de Limours St Rémy Lès Chevreuse Cedex rnce Tel : 33 (0) x : 33 (0) CLCULTO SHEET Stinless Steel Vloristion Project Design Exmple 5 Welded joint de by R Dte ug 00 Checked by H/B Dte Oct 00 Revised by EB Dte pril 00 The contributions to the eld force components (t ll points of the elded joint) from the pplied force components re : x,ed 10, x = = = 0, 017 k/mm / 00 y y,ed 15,y = = = 0, 05 k/mm / 00 z,ed 150, z = = = 0, 5 k/mm / 00 The vrious contributions to the eld force components per unit length of eld t the point () from the pplied moment components re :, y =, Ed, ( 15) = 50,7 10 ( / ) 8,78 10 = 7 /mm, z =, Ed, ( 14) = 50,7 10 ( / ) 8,78 10 = 71 /mm, ( 15),x =, Ed = 1,41 10 ( / ),77 10 = /mm, x =, Ed, ( 14) = 3,4 10 ( / ),01 10 = 00 /mm Combining the contributions t the point () from the forces nd the moments one obtins : x,ed = y,ed = z,ed =, x,x, x y, y, y, z, z = = 43 /mm = 5 7 = 747 /mm = = 9 /mm These resultnt induced force components per unit length re for elded joint ith eld throt size of 1mm throughout its entire effective length. 14

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