A pre-stressed concrete beam 100 mm wide and 300 mm deep is pre-stressed by straight wires carrying an initial force of 150 KN at an eccentricity of 50 mm. Determine the loss of pre-stress due to elastic deformation of concrete if the area of steel wires is 188 mm2. Take EB and Ec as 210 KN/mm2 and 35 KN/mm2
1
40 N/mm2
2
60 N/mm2
3
20 N/mm2
4
80 N/mm2