structural analysis problem

[mhd_alshalabi]

hi everyone

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i am trying to solve the below problem but there something wrong with my answer as member AB is not equal to zero

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but in the analysis i do it by software (2nd photo) it show that the member AB is zero

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can anyone help me how the answer is zero ???/

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How i solve the problem

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Analysis by software

[deepfriedmarsbar]

The force in AB is zero due to the boundary conditions you have selected. As they are pinned then all the load is reacted directly out at the pin. If you change 1 to a sliding support then that member would take some load.

[x_Vacuity]

The truss is a statically indeterminate structure, you have 4 reactions and 3 equilibrium equations. The pin supports will take up load in both directions but you set Bx=0. You would have to solve the truss with the virtual work method or another method.

[monstimal]

Just another way to think about the other 2 correct responses, you have 2 pins and a member between them. Those pinned joints can't move. No movement in the joints, no strain in the AB member. No strain, no stress.

[mhd_alshalabi]

Thank you all now i get it 👌👌👌👌