Assignment $1$

$[30$ MARKS$]$

QUESTION $1$

The truss shown in Figure $q1$ below is made of timber $($SA Pine$).$ It is supported by a pin at D and

a roller at A$.$ Determine the member forces on the structure using the FORCE METHOD. Applied on the truss is a UDL of $2k\frac{N}{m}$ along member DC$,$ and a force of $18\mathrm{.}03kN$ at joint C$,$ which makes an angle of $33\mathrm{.}7$ with the horizontal respectfully. The truss is reported to be made using $2$ types of timber profiles, and these are clearly marked as $1$ or $2($indicated with a boxed number, $1$ and $2).$ It is reported that for profile $1,$ the area, $A_1=625c{m}^2,$ and for the second profile, $A_2=750c{m}^2.$ Take $E=55$ GPA.

$2$

SAN$37012024$

Assignment $1$

$[60$ MARKS$]$

QUESTION $2[60$ MARKS$]$

For the frame shown in figure Q$2$ below, A and C are known to be fixed supports. Joint B is known to be welded $($thus also fixed$).$ Determine the reactions and member end forces for the frame using the STIFFNESS MATRIX method. Also plot the Axial and Bending moment diagrams. Take:

$A=150c{m}^2$

I $-35c{m}^4$

$*$

PLEASE NOTE:

Write eligibly, in a step$-$by$-$step manner, or you can type in word $($DO NOT SUBMIT EXCEL PRINTOUT $-$ Zero marks will be awarded$).$

Round off answers to $3$ decimals. Do not provide final answers in fractions.

Wrong units will make you lose marks. On this level you should not be struggling with units.

Use the correct method. Yes, other methods can obtain the answer, however, only attempts of flexibility method and matrix stiffness method will be considered.

TOTAL $=90$ MARKS

OUNISA $2024$