Problem $1(26$ points$)$

A design engineer has selected a single angle, L$8$x$6$x$1,$ A$572$ steel $($yield stress $=50,000$ psi$)$ as a tension member in a truss. The load it will be subjected to is $255$ kips in tension $($load $=255,000lb)($see image below$),$ which is exerted on the cross$-$sectional area $($represented by hashed line at the forefront of diagram$).$

Two bolt$-$holes are punched $(\frac{1}{2^{\text{'}\text{'}}}$ diameter$)$ as shown in the diagram below for a connection. The factor of safety selected in the connection area is $2\mathrm{.}5($the punching machines are old so the design engineer is especially worried about over$-$stressing the angle$).$

Key data for angle, from steel shape catalog: Area $A=13\mathrm{.}00$ i${}^{}$n2, Thickness of each leg, $t$:$1^{?},A572$ steel, $F_y=50,000$ psi

What is the tensile strength of this assembly at the critical location$($s$)$ on the angle, in $l\frac{b}{i}{n}^2($ psi $)?$

ANSWER

isi $(20$ points$)$

Is the angle sufficiently large to satisfy the required factor of safety for tensile load? $($Select A or B and write down the two values you are comparing and the inequality $($i$.$e pts with the values compared are included; just the correct answer with no work is only worth $1$ pt $)$Problem $1(26$ points$)$

A design engineer has selected a single angle, L$8$x$6$x$1,$ A$572$ steel $($yield stress $=50,000$ psi$)$ as a tension member in a truss. The load it will be subjected to is $255$ kips in tension $($load $=255,000lb)($see image below$),$ which is exerted on the cross$-$sectional area $($represented by hashed line at the forefront of diagram$).$

Two bolt$-$holes are punched $(\frac{1}{2^{\text{'}\text{'}}}$ diameter$)$ as shown in the diagram below for a connection. The factor of safety selected in the connection area is $2\mathrm{.}5($the punching machines are old so the design engineer is especially worried about over$-$stressing the angle$).$

Key data for angle, from steel shape catalog: Area $A=13\mathrm{.}00$ i${}^{}$n2, Thickness of each leg, $t$:$1^{?},A572$ steel, $F_y=50,000$ psi

What is the tensile strength of this assembly at the critical location$($s$)$ on the angle, in $l\frac{b}{i}{n}^2($ psi $)?$

ANSWER

isi $(20$ points$)$

Is the angle sufficiently large to satisfy the required factor of safety for tensile load? $($Select A or B and write down the two values you are comparing and the inequality $($i$.$e pts with the values compared are included; just the correct answer with no work is only worth $1$ pt $)$