Question

A1 60° A14 A15 600 17 16 12 600,60% 604 60% 601 60 10

The 2-D section of a truss carrying the TV screen consists of 24 members. Each horizontal and inclined member is 3 ft long, each of the 9 vertical short members is 1 ft long. The Q1 lb TV weight is equally distributed to 5 members. The weight of the truss is Q2 distributed equally to 9 forces. Calculate:

1) Select the zero force members

2) The reactions at A1 & A2

Answer 1

A1 60° 17 12 600 60% 601 60 60.60 A. A24 A22 A A20 A A 180 lb 393 lb Zero Force members: A,,A24,A1jA2n,4642 and AA1S a) Due to symmetry AA2 2 180+393 2 = 286.5 lb