Truss question!!
Truss question!!
(OP)
For a pin jointed truss that is statically determinate both externally as well as internally (i.e. no. of members=(2xno. Of joints-3), suppose if the axial force in one of the members is zero, what is the contribution of such member?If I remove that member the truss will become unstable(i.e. no. of members<(2xno. Of joints-3)) at the same time that member is not in a state of stress. Is it that the member contributes just for stability?Can anyone clearify?What should be the minimum cross sectional area of that member?
Help please
Help please






RE: Truss question!!
Usually these are being used to reduce the length of the compression members.
The cross section of this type of member it's not so important - the moment of inertia (both directions) counts.
The general rule is that the member used to brace compression member should be able to develop approx. 10% of the force in the member being braced.
RE: Truss question!!
Unbalanced loads are sometimes required by code (wind loads on pitched roofs, snow loads) while some are developed at the discretion of the engineer (unbalanced live loads).
For a floor truss, there will always be times when live loads will not be uniformly placed over your tributary area. Therefore, your zero-member may be required.
RE: Truss question!!
Removing the web may not make the truss unstable, but will force you into an indeterminate analysis.
RE: Truss question!!
For any truss in pratice, you have always nonzero axial force members, 'cause truss is a much more complex structure.
CV
carlosvalinhas@netcabo.pt