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GIVEN: An AASHTO Type II precast prestressed pretensioned girder will be used to carry a 6 inch cast-in-place slab to form a composite beam that will span 65 feet between simple supports. The girder will be made using normal weight concrete with f'c = 6000psi. The slab concrete will be constructed, unshored, of normal weight concrete with f'c = 4500psi. The tendons are to be Grade 270 stress relieved " diameter with a constant eccentricity of e = 11.59" below the cge of the AASHTO girder. Assume the time dependent losses of prestress are 15%. Superimposed dead load in addition to the slab and girder, applied at the time of placement into service, is 185plf (barrier rail, future wearing surface, piping, etc.) and live load is 1150 plf. REQUIRED: Using ACI allowable stress and other requirements and knowing that the girder is an interior (intermediate) girder with a girder spacing of 7.25 feet: a) calculate the composite section properties b) calculate the number of tendons, checking that there are no over-stresses at transfer check stresses after slab is poured (3 months after transfer, all prestress loss occured) d) check stresses at service load NOTE: don't redesign the tendons for part c and d, comment if there are overstresses and suggest methods of remedy, if necessary. Also, don't worry about exact placement of tendons, assume that the number of tendons that you calculate in part b will fit in the girder with required cover and spacing at the eccentricity given. GIVEN: An AASHTO Type II precast prestressed pretensioned girder will be used to carry a 6 inch cast-in-place slab to form a composite beam that will span 65 feet between simple supports. The girder will be made using normal weight concrete with f'c = 6000psi. The slab concrete will be constructed, unshored, of normal weight concrete with f'c = 4500psi. The tendons are to be Grade 270 stress relieved " diameter with a constant eccentricity of e = 11.59" below the cge of the AASHTO girder. Assume the time dependent losses of prestress are 15%. Superimposed dead load in addition to the slab and girder, applied at the time of placement into service, is 185plf (barrier rail, future wearing surface, piping, etc.) and live load is 1150 plf. REQUIRED: Using ACI allowable stress and other requirements and knowing that the girder is an interior (intermediate) girder with a girder spacing of 7.25 feet: a) calculate the composite section properties b) calculate the number of tendons, checking that there are no over-stresses at transfer check stresses after slab is poured (3 months after transfer, all prestress loss occured) d) check stresses at service load NOTE: don't redesign the tendons for part c and d, comment if there are overstresses and suggest methods of remedy, if necessary. Also, don't worry about exact placement of tendons, assume that the number of tendons that you calculate in part b will fit in the girder with required cover and spacing at the eccentricity given

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