A wood beam in a historic theater is reinforced with two angle sections at the outside lower corners (see figure). If the allowable stress in the wood is 12 MPa and that in the steel is 140 MPa, what is the ratio of the maximum permissible moments for the beam before and after reinforcement with the angle sections? See Appendix F Table F-5(b) for angle section properties. Assume that E_w =12 GPa and E_s = 210 GPa.

(a) Find the maximum permissible positive bending moment for a 1- m wide strip of the slab.

(b) What is the required area of steel reinforcement, As, if a balanced condition must be achieved? What is the allowable positive bending moment?

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