Problem H$05-02.$ Reinforced$-$concrete beam design $[$Points: $1/5].$

Design the cantilever rectangular reinforced beam shown in the figure. Provide a maximum of #$8$ size

bars, in two rows if necessary; $f_c^{\text{'}}=3,000lb\frac{f}{i}{n}^2,f_y=50,000lb\frac{f}{i}{n}^2.$ Sketch the design. Include the self$-$

weight of the reinforced concrete beam. Apply Load Combination $2$ only. Comply your design with the

ACI specifications for beams $($see slides $28-32$ of lecture $\text{'}$L$07-$ Concrete Flexion I$\text{'}.$ Explain why the re$-$

inforcement steel has to be laid at the top and not at the bottom. Exploit the instructor spreadsheet calcula$-$

tor posted in D$2$L to speed up the numerical calculations.

$D=2,500l\frac{b}{f}t(excluding$ self weight$)$ Problem H$05-05.$ Double reinforced$-$concrete beam design $[$Points: $1/5].$ Design a double$-$reinforced concrete beam to resist the moment due to a service dead load D$=150,000$ lbf$**$ft $($including self$-$weight$)$ and the moment due to a service live load L$=160,000$lbf$**$ft $.$ Apply Load Combination $2$ only. The beam width is limited to $11$in $,$ and the effective depth d is limited to $20$in $.$ The compression steel cover is $3$ in from the top $($measured to centerline of compressive rebars$).$ Use fdeg $\_($c$)=3,000$lb$($f$)/($i$)$n$^(2),$f$\_($y$)=60,000$lb$($f$)/($i$)$n$^(2).$ Exploit the instructor spreadsheet calculator posted in D$2$L to speed up the numerical calculations. Hint$*$: Review the algorithm of Slides $14-24$ of the $\text{'}$L$9-$ Concrete Flexion III' handout.