(Solved): Please someone help? em 1: Transformed Moment of Inertia and Elastic Deflection Given: The cent ...

Please someone help?

em 1: Transformed Moment of Inertia and Elastic Deflection Given: The center of the top and bottom rebars are placed 2.5 " from the top and bottom faces. Top Reinforcement: 2 no. 4 Rebar Bottom Reinforcement: 4 no. 9 Rebar Use textbook table A-1 for rebar properties $\begin{array}{l}{E}_s=29,000\mathrm{ksi}\\ E_c=3,600\mathrm{ksi}\end{array}$ Unit weight of plain concrete $=145\mathrm{lb}/f{\mathrm{t}}^3$ a. Find the transformed moment of inertia of the composite section. b. Calculate the reinforcement ratio $?$ where $?$ is $A_{sb}/bd.A_{sb}$ is the area of the bottom steel, $d$ is the depth from the top face of the beam to the bottom steel, and $b$ is width of the beam. c. A 30' simply supported beam has this cross-section. Ignoring the effects of cracking, how much would the beam deflect under its own self-weight and a live load of $0.64\mathrm{kip}/\mathrm{ft}$ ? d. Often the unit weight for reinforced concrete is assumed to be $150\mathrm{lb}/{\mathrm{ft}}^3$. Repeat part c. using this assumption. e. Repeat part c. using the gross moment of inertia. Note: the gross moment of inertia is the moment of inertia assuming the beam is entirely concrete. f. Briefly discuss the difference between the deflections calculated in parts c-e. When could the simplifying assumptions made in parts $d$ and e be useful? Are they safe assumptions to make?