$3\mathrm{.}4$ A girder $12m$ span is fixed horizontally at the ends. A downward vertical load of $80kN$ acts on

the girder at a distance of $4m$ from the left hand end and an upward vertical force of $40kN$ acts

at a distance of $6m$ from the right hand end. Determine end reactions, fixing couples. Draw BM

and SF diagrams for the girder.

Exercise $124-1.$ A fixed beam of length $8m$ carries a uniformly distributed load of

$wk\frac{N}{m}$ run. Determine $w$ if

$($i$)$ maximum bending moment is not to exceed $36kNm$

$($ii$)$ maximum defiection is not to exceed $\frac{1}{2000}$ of the length.

$E.I=7200kN{m}^2[Ans.(i)6\mathrm{.}75k\frac{N}{m}$run, $(ii)2\mathrm{.}7k\frac{N}{m}$ run$]$