How would i resolve the forces so they are acting on the bottom joints.


We consider each member that has mid-span loads as a simply supported beam and resolve the loads on the beam to vertical reactions and those reactions will be loads at those joints.

Then solve the truss with the midspan loads removed and reactions added as joint loads.

After we find all the member axial forces and supports' reaction we Solve that member as a simply supported beam with appropriate axial compression or tension and find the moments and shears on that member.

For example, the first bottom member on the right, say we call the support B and the joint to its right A:

$ \Sigma M_B=0 \ 312*5.05/6.7= 235kN =P_A \rightarrow \ and \ 312-235= 77=P _B $

So we add these two loads to joints A and B and remove them from mid-span of this member.

Then we solve the truss and find the axial load for AB which should be tension and solve it.

We need to pay extra attention to those members with compression, checking for buckling with both the secant method and Euler's critical buckling load.


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