# Need help with truss problem

1. Apr 11, 2006

### usfz28

I need to find all the zero force members, and solve for the other members. I am at school right now but I can definantly tell AB and AC are zero force members. When I get home I will see what else I can come up with. Also I cannot remember how to get the angled trusses :grumpy: Also All 3 downward forces are 20 kips

http://img.photobucket.com/albums/v625/BrockBlackZ/prob1.gif [Broken]

Last edited by a moderator: May 2, 2017
2. Apr 11, 2006

### usfz28

By=22.11 and Iy=57.89... Since Bx=0 then I guess BD and DG are zero force members, How about GJ? Also sicne AC is zero is CE, EH, HK also zero? I also think FI is zero too. I know there are alot of zero force members in here just need some help finding them

3. Apr 11, 2006

### civil_dude

Assuming pinned connections, the only obvious zero force members are ED, HK & KJ.

4. Apr 11, 2006

### civil_dude

Since the lower right reaction is a roller, then FI will also be a zero force member. I would find your reactions and start at I.

5. Apr 11, 2006

### usfz28

Why would ab and ac not be zero focer membes?

6. Apr 11, 2006

### Cyrus

Go back and read when the assumption for zero force members is valid. If that does not help then report back.