Q.1
The loss of prestress due to elastic deformation of concrete depends on ____________
  • a) Modular ratio and average stress
  • b) Modular elasticity and shear
  • c) Prestress in concrete
  • d) Modulus of elasticity of steel
Q.2
The term Ec in losses developed by elastic deformation is expressed as ____________
  • a) Pe/A
  • b) Pc/Ea
  • c) P/AcEc
  • d) Ea/El
Q.3
The term Es in losses developed by elastic deformation is defined as ____________
  • a) Shear in steel
  • b) Torsion in steel
  • c) Strain loss in steel
  • d) Loading in steel
Q.4
The loss of stress in steel due to elastic shortening or deformation is ____________
  • a) αefc
  • b) αcfc
  • c) αc/fc
  • d) αe/fc
Q.5
A pretensioned concrete beam, 100mm wide and 300mm deep in prestressed by straight wires and modulus of elasticity of steel and concrete areand 35n/mmFind modular ratio?
  • a) 14
  • b) 7
  • c) 6
  • d) 10
Q.6
A pretensioned concrete beam 200mm wide and 300mm deep, is prestressed by straight wires carrying an initial force of 150kn at eccentricity of 50mm, area of steel wires is 188mmFind initial stress in steel?
  • a) 1400
  • b) 800
  • c) 200
  • d) 100
Q.7
A pre tensioned concrete beam 100mm wide and 300mm deep, initial force of 150kn at an eccentricity of 50mm, moment of inertia is 225×106mminitial stress in steel is 400n/mmmodular ratio isEstimate the percentage loss?
  • a) 10%
  • b) 5%
  • c) 14%
  • d) 20%
Q.8
A rectangular concrete beam 360mm deep and 200mm wide, is prestressed by means of fifteen 5mm diameter wires located 65mm from the bottom of the beam and three 5mm wires, located 275mm from top of the beam, initial tension stress is 840n/mmCalculate prestressing force?
  • a) 504×102kn
  • b) 500×102kn
  • c) 620×102kn
  • d) 400×102kn
Q.9
A post tensioned concrete beam, 100mm wide and 400mm deep is prestressed by three cables, each with a cross sectional area of 50mminitial stress of 1200n/mmCalculate the stress in concrete at level of steel?
  • a) 2.4n/mm2
  • b) 2.0n/mm2
  • c) 2.7n/mm2
  • d) 1.5n/mm2
Q.10
The loss of stress due to successive tensioning of curved cables in elastic deformation of concrete is estimated by considering ___________
  • a) Initial stress
  • b) Average stress
  • c) Bondage stress
  • d) Anchorage stress
0 h : 0 m : 1 s