ART $2122-$ STRUCTURES I

Assignment #$6$

For the following problems, indicate the given values of $P,A,$ or $f$ and solve for the missing value

Sketch diagram

Show all workWhat axial load may be placed on a short timber post whose actual cross$-$sectional

dimensions are ${9\mathrm{.}5}^{\text{'}\text{'}}{9\mathrm{.}5}^{\text{'}\text{'}}$ if the allowable unit compressive stress in the wood is $1100$ psi?

$(4$ pts$.)$

A short concrete pier, $18"18",$ supports an axial load of $150$ kips. Based on allowable

stress, $F_c=900$ psi, is the construction safe?

$(6$ pts$.)$

What force must be applied to a steel bar that is $1in.$ square and $2ft$ long to produce an

elongation of $0\mathrm{.}016$ in$.?(4$ pts$)$

How much will a nominal $8"8"$ Douglas fir post shorten under an axial compression load

of $45$kips if the post is $12ft$ high? Use $E=1500$ksij. $(7$ pts$.$