Effective length of longitudinal beam in bridge pipe rack

[allimuthug]

HI
I have a Bridge pipe rack of 12meter long x 3meter wide and 7 meter tall.
The longitudinal beam is connected by plan and vertical braces as shown in the picture.

1. The effective length of longitudinal beam Lx and Ly is 2m since it is braced in vertical and longitudinal direction. Also, the function of lx and ly is the slenderness ratio. when axial load is applied to the longitudinal beam the braces prevent it from buckling in transverse and longitudinal direction.

2. The Unsupported length of longitudinal beam is 2meter since the longitudinal beam is braced in minor axis as shown in the figure.

3. For deflection check the length of longitudinal beam is 12m.

4. Please suggest me a better truss arrangement for bridge pipe rack with merits and demerits.

Friends please correct me and help me.