last 3 digits= 888

Q1. a. An unsymmetrical I section prestressed concrete beam of top flange (350 X 60 mm) in size, bottom flange of (200 X 60 mm), 60mm thickness of web and overall depth of 500 mm is prestressed with 18 numbers straight steel wires of 9 mm diameter located at a distance of 25 mm from the bottom of the soffit and 7 numbers of straight steel wires of 6 mm diameter located at a distance of 25 mm from the top of the beam. The wires were initially tensioned on the prestressing bed with an initial prestress of 8+(W/600) (Last 3 digits of your id) GPa. The length of the beam is 10 m. Calculate the total percentage loss of stress in the wires at top and bottom. Assume the beam is post tensioned beam and all the wires stressed simultaneously tensioned by using the following data: Relaxation of steel stress=4.5% of initial stress Shrinkage strain in concrete for post tensioning = 200 x 106 Creep Coefficient =1.6 Friction coefficient for wave effect-0.0015+0.001* (Last 3 digits of your id) per metre Slip at anchorage=1.5 mm Modulus of elasticity for steel = 210 GPa Modulus of elasticity for concrete= 35 GPa b. What are the measures that are suggested to be taken to reduce the losses in prestressed concrete members for the above problem?