Question

•The truss structure has a span of 30m and height of 3m.There are altogether 7 trusses included in the following diagram.
•Design Loads include dead load to self-weight of decking,truss structure,decorations and so on, G=48kN (design value, no loading factor required here) plus live load due to moving vehicle P=420kN (design value, no loading factor required here). Calculate truss member forces due to the combination of dead load and live load at one joint.

311V10=104 PUUDU gf of DW 91 91 91 UN 9 Mg 3 do

*Just calculate it using the diagram with method of joints or method of section.

Answer 1

. 3m JA 10:45 IB Ve Vo VE VE VG зVA 48кы чакы чвку еко вы еке ке ве чѣку vk. VP-420KN --- 3x10 P=420 kw - - - - - - > - Forces in touss member when live load is at point F. Que to symmetry A = k = 18x7 + 20 = 426 kN. - 2 ARBY FAB By Method of joint. 3 point A For Sin45 = 426KN FAL = 42652 kN (c) - FAB = FALCOs 45 = 42652 6545 5 kg = 426 kN (T) IVA=426kN

FBL . Point B FAB FBC * 48kN . FL= 48KN (T) FBc = FAB = 426 KN (T) Point L FLM 426.55 kW 26151 Aus FLC HBKN Fee Sin45=4265260845 - 48 Fee = 37852.tact) 138852 ffcm 2 Fim = 42652 sin45 + 37852 60545 - Flm = 804 KN (C) poind a From = 38852 sin 45 +48 ) Fcm = 436 KN (IT) FcD =(-38852 cos45) +426D FCD = 38 KN (T) Point m 1206 Fed m Brot 804KW M Fmn 450€ Emp= 436 = 43652 AN(C) 43ent Kfmo Sin45 FmN= 804 - 43652 6545 - FMN = 368kN (C). In

43652 LFON L D t 38KN For 148 368AN N fro 4841NY BENE = Poind D FON = 4365260545 +48 FON = 4 B4 kN () FDE = 43652 sin 45 - 38 FDE = 398 KN (C) point N Fue = yang = 484 52 kg () Sin 45 FNo = 484 52 66545 -368 fNo = 116kN (T) Point E N Fro = 484526545+48 E FEO = 532 KN (T) fgf = 48472 sin45 +398 7 FEf = 882 KN (C) Note Point & For = 532 = 53252KN (C) Sinus Fpo = 5325260545 +116. FPO = 648 KN . 48452 your blood to 398KN E FEE 398KN I LUBAN чBky ve) 116 KN B E < N45" SI532 Fo

Due to Symmetrical touss all the forces in Roght Sidled members from point F are Same as left side. i Fkg = FAB = 426 KN (T) Fkg = FAL = 426 JŽ KN (C) FJT = FBL = 48 kw (1) FJI = FBC = 426 KN (T) Ft I = Fee = 378J2XN (1)

U Fts = Fim = BoykN Ce) ESI = Fmc = 436 KN (7) FSH = fmp = 43652 KN (C) FSR = FMN = 368 KN (C) FAG = FDE = 398 KN (C) For = Fon = 484 kN (T). FNE = 48452 kN (C) Fro = 116KNCT) FGF = FEF = 882 KNCC) Face = FEO = 532INCT) For = For = 53 252 KN CC) Fop = Føp = 648 KN CT) FRG