Problem $2$:

Select one of the $2$ optional structures presented below and answer the following questions:

Is this a determinate or an indeterminate structure?

Consider how the forces are transferred to the supports. What internal forces develop along the different members comprising the structure considered?

Using what we have learnt in D$28$DS calculate the internal actions $($bending moments, shear forces and axial forces$)$ developing along the members of the structure due to the application of the external loads.

Model the structure using LINPRO and confirm that solutions obtained are in agreement with those calculated in question $(3)$ and the solutions provided in the brief.

Consider how you would design each member of the structure. What would you need to consider?

Design the key $($critical$)$ members employing the permissible stress approach. Choose the appropriate materials and element cross$-$sections. Consider only the stresses acting normal to the cross$-$sections you are designing $($ignore shear stresses for now$).$ Achieve an overall safety factor of $2$ for your stresses $($factor of safety $=f\frac{y}{{}_{\text{m}\text{a}\text{x}}}$ where $f_y$ is the yield stress of the material in compression and tension and $o_{\text{m}\text{a}\text{x}}$ is the maximum value of stress developing normal to the cross section considered$).$ Using Linpro make sure that no member of the structure deflects more than $20mm$ in any direction. Assume that the structure when loaded exhibits linear elastic behaviour

Option $1$