CONSOLIDATION OF STEEL PLATE GIRDERS APPLICATION OF EUROCODES

Transcription

1 BULETNUL NSTTUTULU POLTEHNC DN AŞ Publat de Unvertatea Tehnă Gheorghe Aah dn aş Tomul LV (LX), Fa., 01 Seţa CONSTRUCŢ. ARHTECTURĂ CONSOLDATON OF STEEL PLATE GRDERS APPLCATON OF EUROCODES BY ŞTEFAN. GUŢU *, CĂTĂLN OGA and RALUCA BOLDOR Tehnal Unverty of Cluj-Napoa Faulty of Cvl Engneerng Reeved: January 30, 01 Aepted for publaton: arh 30, 01 Abtrat. n th paper we fou on the degn ba onernng the teel plate grder onoldaton. Th onoldaton aheved by addng a upplementary plate to one flange or plate to both flange, whh reult n an nreae of the retane haratert and of the bendng retane. The degn methodology adapted to the European ode EN 1993: Degn of Steel Struture. Part 1-1: General Rule and Rule for Buldng and Part 1-5: Plated Strutural Element.A degn example whh wll exemplfy the theoretal methodology and ome onludng remark are alo preented n th paper. Key word: teel plate grder; trengthenng; euro ode; effeny analy. 1. ntroduton Phyal and dynam wear and alo the modfaton n the explotaton ondton of a brdge an lead to the neety of onoldaton and rehabltaton work, epeally wth the purpoe of enhanng the bearng apaty of the truture. By addng a upplementary element to one flange or element to both flange, an nreae of the eond moment of nerta and, onequently, a reduton of the tree and deformaton under the lve loadng are obtaned. * Correpondng author: e-mal: tefan.gutu@fdp.utluj.ro

2 116 Ştefan. Guţu, Cătăln oga and Ralua Boldor n Fg. 1 ome poblte of nreang the ro-eton haratert are preented. Fg. 1 Steel plate grder onoldaton. The effeny of the onoldaton dretly dependent on the level of the grder unloadng when trengthenng operaton are performed; the mot ommon ae that when the grder loaded only wth the permanent load.. Degn Ba n Fg. we llutrate the tate of bendng tree of a teel plate grder n the ae of the trengthenng wth a T element added to the bottom flange. Fg. State of bendng tree on trengthened grder. Phae : Grder unonoldated, loaded by permanent aton: g Eg, (1 a) y, eff

3 Bul. nt. Polt. aş, t. LV (LX), f., g Eg. (1 b) y, eff Phae : Grder onoldated, loaded by lve aton: Bede the tree of phae, the followng tree are added: P ', ( a) EP y',eff, P EP ', ( b) y', eff, where y',eff, the moment of nerta of the onoldated ro-eton. The tate of the tree n the ro-eton and n the added element,, f = +, (3 a) Eg EP ' y z z y,eff y',eff, γ 0 f = +, (3 b) Eg EP ' y z z y,eff y',eff, γ 0 f =. (3 ) EP y z y',eff, γ 0 Beaue of the hange n the ro-eton of the flange, the gravty entre wll modfy o that a re-evaluaton of the ro-eton la neeary..1. Elat Grder Deformaton By the modfaton of the grder rgdty, favourable effet are alo obtaned n onneton wth the elat grder defleton. The defleton for a grder wth varable ro-eton an be alulated wth the relaton δ = 5 max 5.5 max 48 L L E m 48 E, (4) y where m = l the average moment of nerta of the grder. L

4 118 Ştefan. Guţu, Cătăln oga and Ralua Boldor t reult the followng defleton value: a) unonoldated grder b) onoldated grder ( g + ϕ3p) L 5.5 δ =, (5 a) 48 E 5.5 g ϕ3 P δ = + 48 L, (5 b) E y y where y the moment of nerta of the onoldated ro-eton. 3. Worked Example Next the tate of the bendng tree of a onoldated teel plate grder of a brdge upertruture analyed. The followng degn data are known: A. Charatert of the grder: a) Elevaton (Fg. 3). y Fg. 3 Grder elevaton. b) ateral, loadng, ro-eton (Fg. 4). STEEL: S355 L CROSS-SECTON: at mddle pan: flange: b f t f = mm web: h w t w =,600 1 mm at upport: flange: b f t f = mm web: h w t w = 1,600 1 mm Fg. 4 ateral, loadng, ro-eton.

5 Bul. nt. Polt. aş, t. LV (LX), f., ) Bendng moment: Ed = 1,500 kn m, dvded n: Eg = 4,400 kn.m; EP = 17,100 kn.m. B. Conoldated ro-eton (Fg. 5). Fg. 5 Conoldated ro-eton. 3. Conoldaton Soluton Analy a) Unonoldated grder A. Cro-eton la Compreon flange Cla 3 Web t (650 1) / = = 10.6 < 14 ε = = t 30 f Cla 4 Cro-eton Cla = 4. w,600 = = 16.7 > 14ε = =

6 10 Ştefan. Guţu, Cătăln oga and Ralua Boldor B. Effetve ro eton of web The web an nternal partal ompreed plate (Fg. 6). Fg. 6 nternal partal ompreed plate. For ψ ρb = p 0, beff ρb ; be beff ; be 0.6beff < = = 1 1 ψ = =. n th ae ψ = 1; k = 3.9. t reult: bp / t λp (3 + ψ) λp = = 1.93 > ; ρ = = 0.49 < 1 8.4ε λ k and onequently b eff = m; b e1 =6 m; b e =38 m. n Fg. 7 the effetve ro-eton and the tre dtrbuton are preented. p Fg. 7 The effetve ro-eton.

7 Bul. nt. Polt. aş, t. LV (LX), f., The followng tree are obtaned: 4 n Ed 1, = 6 14 = 3,805 dan/m > f y = 3,550 dan/m y,eff 8,03 10 ; 4 n Ed 1, = 6 14 = 3,33 dan/m < f y = 3,550 dan/m y,eff 8, b) Conoldated grder The effetve ro-eton of the web re-evaluated, aordng to the tre dtrbuton preented n Fg. 8. The followng value are obtaned ψ = 0.60, k k = ψ ψ = 15.1, bp / t λp (3 + ψ) λ p = =.4 > 0.673, ρ = = 0.39 < ε λ p The web effetve ro-eton b eff = = 633 mm; b e1 = = 53 mm; b e =380 mm. Fg. 8 Stre dtrbuton. n Fg. 9 the effetve ro-eton preented.

8 1 Ştefan. Guţu, Cătăln oga and Ralua Boldor Fg. 9 The effetve ro-eton... State of Stree P h a e : Unonoldated grder, loaded by permanent aton (Fg. 10). The followng value are obtaned: Eg g z g Eg = = 779 dan/m, = 680 dan/m. y,eff y,eff Fg. 10 Unonoldated grder.

9 Bul. nt. Polt. aş, t. LV (LX), f., P h a e : Conoldated grder, loaded by lve aton: To the tree of phae, the followng tree are added (Fg. 11): P EP ' = 730 dan/m, y',eff, P EP ' = 1,37 dan/m. y',eff, Fg. 11 Conoldated Grder. The fnal tate of the tree n the ro-eton and n the added element,, a follow (ee Fg. 1): Fg. 1 Fnal tate of the tree.

10 14 Ştefan. Guţu, Cătăln oga and Ralua Boldor f 779,730 3,509 dan/m 3,550 dan/m, Eg EP ' y + z = + = = y,eff y',eff, γ 0 = + = + =, Eg EP ' z z 680 1,37,007 dan/m y,eff y',eff, 4 EP 17, f y = = 1,977 dan/m y',eff, 1,11 10 γ 0 4. Conluon By addng a upplementary element to the bottom flange, the followng reduton of the bendng tree are obtaned: a) top flange n 3,805 3,509 Δ = 100 = 100 = 7.8 % ; n 3,805 b) bottom flange n 3,33,007 Δ = 100 = 100 = 40 %. n 3,33 Obvouly, the approprate onoldaton oluton for eah partular ae of teel plate grder ha to be analyed. Addng a longtudnal tffener bede the element added to one or to both flange an alo be favourable. REFERENCES oga P., Guţu Şt., Podur metale. Întreţnere ş reabltare. Ed. UT.PRESS * * * Degn of Steel Struture. EUROCODE 3. Part 1, EN 1993: 003 * * * Proetarea truturlor de oţel. Partea 1-1: Regul generale ş regul pentru lădr. Eurood 3, SR EN /006. * * * Proetarea truturlor de oţel. Partea 1-5: Elemente dn plă plane oltate în planul lor. Eurood 3, SR EN /006.. APLCAREA EURONORELOR LA CALCULUL CONSOLDĂR GRNZLOR ETALCE CU NĂ PLNĂ (Rezumat) Se prezntă baza de alul prvnd onoldarea grnzlor metale u nmă plnă prn adăugarea unor elemente udate la una au la ambele tălp ale grnz, prn are e majorează aratertle de reztenţă ş mplt e poate măr apatatea portantă la înovoere a grnz. etodologa de alul ete adaptată la norma europeană

11 Bul. nt. Polt. aş, t. LV (LX), f., prvnd alulul elementelor dn oţel, normatvul EUROCODE 3. Part 1. Degn of Steel Struture. EN 1993: 003, repetv tandardele române orepunzătoare: SR EN /006. Eurood 3: Proetarea truturlor de oţel. Partea 1-1: Regul generale ş regul pentru lădr ş SR EN /006. Eurood 3: Proetarea truturlor de oţel. Partea 1-5: Elemente dn plă plane oltate în planul lor. etodologa de alul ete exemplfată în adrul unu exemplu numer, are faltează înţelegerea baze teorete de alul.