Question

Problem No. 2 (100 points) For the Baltimore bridge truss shown below answer the following questions: 1) Calculate Reaction Forces (FBD is already drawn assuming a pin support at A and a roller support at I) (10) 2) What is status of the Truss (determinate or indeterminate)? (10) 3) Obtain ALL the Zero force member (30) 4) Using method of Joints, find force in member PF and PG specify if these forces are in Tension or Compression? (25) 5) Using method of Section find Forces in members EP and LM, specify if these forces are in tension or compression. (25) Hint: draw one section to find force EP and draw another section to find force LM. M 2 m 2 m в с D E F ( 5 KN 3 KN 16 m.8@2 m

Answer 1

Answer - 5KN 5KN 3KN 8 fm = 16m E&x=0 sty=0 Ay + ly = 8kN EMI-0 5X8+ 386 - Ayx 16 104 = 3.625 kad IY - 4.375 kW Answer Static indeterminacy = m+r-eJ m = no of member = 29 T= Reaction force = 3 J = no- of points - 16 Ds. = 29+31642 = 0 i e determinate truss rodilo 12) and there is no external third members when there are three members are meet toado, where two members are colinear and will cary zero force. like- NB, wc, mc, LO, OD, LE, HI, JG.

(4) consider the point f. a for FEE Fat 3KNS Efyzo For = 3kal ( Tension) Answer Consider Joint p- - fpfcosys AM QM Apesinys Efy co Fpa + Fop costs = 0 fpu = -3 * =-0.12 KN Fog - Q.12 kall comp.)] Ansoor (5) cut the members em, Of, De and take Right section Lt 5km 3 km

EME=0 Fem X4 of ly X8 = 3x2 Fem = -7.2561 FLM = 7.25 kn (comp.) Answer Rut the membera Lx, TP, er and take lest section. — 6k FEP fePC S45 Ax n A B C D 5kN Trepsinys {fy=0 Ay + FEP sinus = 5 fep sinys -5 -3.625 I fep1.94485 kW (Tension) Answer