ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

(a)(b)

(c) (d)

ENG. SAID ALHADDAD

(e) (f)

ENG. SAID ALHADDAD

Case1: If only two non-collinearmembers form a truss joint and noexternal load or support reaction isapplied to the joint, the members mustbe zero-force member.

Case2: if three members form a trussjoint for which two of the members arecollinear, the third member is a zero-force member provided no externalforce or support reaction is applied tothe joint.

ENG. SAID ALHADDAD

Indicate all the members of the trusses shown that have zero force.

(a) (b)

ENG. SAID ALHADDAD

For the shown truss, determine the force in members EC & EBusing joint method. State if the members are tension orcompression.

ENG. SAID ALHADDAD

For the shown truss, determine the force in members JH, BJ, BI. Stateif the members are tension or compression. The internal anglebetween any two members is 60. The truss is pin supported at A androller supported at F.

ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

Determine the forces in all themembers of the complex truss.State if the members are in tensionor compression.Hint: Substitute member AD withone placed between E and C.

Member Si’ si x*si SiAB 848.53 -1 -1421.86 -573.33BC 848.53 -1 -1421.86 -573.33CD 0 -1.115 -1585.38 -1585.38DE 0 -0.816 -1160.24 -1160.24EF 1005.27 -1.04 -1478.74 -473.47FA 1373.21 -1.44 -2047.48 -674.27EB -1200 1.41 2004.83 804.83FC -1231.19 1.27 1805.77 574.58EC 747.9 -0.526 -747.90 0.00

ENG. SAID ALHADDAD

747.9-x(0.526)=0X=1421.863 F(AD)=1427 Ib

ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

ENG. SAID ALHADDAD

Determine the reactions at the supports

Cz =360 lbAz =200 lbBz = 40 lbBx = 0 lbAy = 0 lbCy = 0 lb

ENG. SAID ALHADDAD

Case1: If all but one of the membersconnected to a joint lie in the sameplane, and provided no external loadacts on the joint, then the member notlying in the plane of the othermembers must be subjected to zeroforce

Case2: If it has been determined thatall but two of several membersconnected at a joint support zeroforce, then the two remainingmembers must also support zeroforce, provided they do not lie alongthe same line.

ENG. SAID ALHADDAD

Determine the force in each member ofthe space truss and state if themembers are in tension orcompression.

Eng. Said Alhaddad