Answer Happy

3. Consider a three-hinged arch which spans 200 feet and has a midspan rise of 20 feet. The arch is constructed so that its form counteracts the bending moment due to a uniform loading. a.) Assume the arch is uniformly loaded vertically with 2 kips/foot. At the quarterpoint, compute the horizontal and vertical forces and the resulting axial force in the arch. b.) This arch is now instead loaded by two concentrated 10 kip loads, one at each quarterpoint. Just to the left of the left quarter-point, calculate the internal horizontal and vertical forces and the bending moment in the arch due only to the concentrated loads. c.) Draw the final moment diagram resulting only from the two concentrated loads. How can the arch be designed to resist this moment?