Creep and Shrinkage Loss

Q. For a pre-tensioned beam, Young's Modulus of steel and concrete are 200 GPa and 35.35 GPa, respectively, If the ultimate shrinkage strain and Ultimate Creep Coefficient are 200 microns and 1.6, respectively, what is the level of sustained stress in concrete at the level of 'steel' if the loss due to creep is three times the loss due to shrinkage?

1. 9 MPa
2. 13 MPa
3. 11 MPa
4. 15 MPa

Q. An ordinary mild steel bar has been prestressed to a working stress of 200 MPa. Young's modulus of steel is 200 GPa. Permanent negative strain due to shrinkage and creep is 0.0008. How much is the effective stress left in steel?

1. 184 MPa
2. 160 MPa
3. 40 MPa
4. 16 MPa