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[10] 1. A 25 ft. reinforced concrete beam is being designed to support a uniformly distributed load. This load has an average value of 1.4 kip/ft with a standard deviation

of 0.3 kip/ft. The average flexural resistance of the beam is 230 ft-kip with a standard deviation of 15 ft-kip, and the average shear resistance of the beam is 45 kip with a standard deviation of 7 kip. 1) [1] Find the global safety factor in both flexure and shear (note: safety factor resistance/load effect) 2) [2] Find the safety index in both flexure and shear 3) [3] If the average flexural resistance is increased to 270 ft-kip with the same standard deviation of 15 ft-kip, find the new safety index in flexure 4) [3] If the standard deviation of the shear resistance is decreased to 5 kip with the same shear resistance, find the new safety index in shear 5) [1] Comment on your results

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