As per recommendation made by IS 1343 for prestressed concrete structures, shear reinforcement need not to be provided when shear force is
Question 2
If 1.6 is creep coefficient, 8.5 N/mm2 is initial prestress in concrete at the level of tendons, 6.0 is modular ratio, 2× 105 is young’s modulus of elasticity of steel and 2 × 10–4 units is the shrinkage strain, then the total loss in concrete due to effect of creep and shrinkage of concrete is
Question 3
A simply supported rectangular concrete beam of span 6 m and c/s 200 mm × 250 mm is to be prestressed with a force of 1200 kN The tendon is of parabolic shape having zero eccentricity at the supports. Beam carries an external UDL of intercity 24 kN/m. The maximum dip of the tendon at the mid span to balance the external load should be
(neglect self weight of the beam)
Question 4
A prestressed beam of 250×400 mm carries a load of 8 KN/m over a span of 10 m including self weight. It has a parabolic cable with eccentricity zero at ends and 100 mm at mid span. If net resultant stress at bottom most fiber at mid span is zero, then force of prestress would be
Question 5
A Prestress concrete beam of span 16 m having cross section as shown in figure is subjected to a total load of 10 kN/m including its self weight.
This beam is prestressed with a prestressing force ‘P’ at 185 mm from Soffit. It eccentricity of thrust line at mid span section is 10 mm above the centre line, value of ‘P’ would be :
Question 6
In simply supported prestressed concrete bema with uniformly distributed loads over its entire span.
Statement1:The size of limitingzone ismaximum at supports and reducestowards themidspan.
Statement 2:The Bendingmoments due touniformlydistributed loadsina simplysupportedbeam are zero atsupports andmaximum at midspan.
Question 7
Which of the following statements are true? 1) Plane section remains plane after bending. 2) Steel and Concrete both are assumed to be linearly elastic. 3) Pressure line is locus of net compressive force on section. 4) Post tensioning is used for railway sleepers.
Question 8
A prestressed concrete beam of span 6 m supports a uniform loading of 4 kN/m over it. The size of the beam is 200 × 400 mm. Assume the density of the concrete 24 kN/m3. Find the magnitude of the concentric prestressing force required to remove any tension in the beam.
Question 9
A rectangular pre-stressed beam 150 mm 300 mm size is used over an effective span of 10m.The cable with zero eccentricity at the supports, and linearly varying to 50mm at the centre, carries an effective prestressing force of 500 kN. Find the magnitude of the concentrated load Q located at the centre of span when the load counteracts the bending effect of prestressing force (neglect self weight)(in kN)
Question 10
A pre-tensioned concrete member if section 200250 mm contains tendons of area 500 mm2 at centre of gravity of the section. The pre-stress in the tendons is 1000N/mm2.Assuming modular ratio as 10.the stress in(N/mm2) concrete is
300 mm size is used over an effective span of 10m.The cable with zero eccentricity at the supports, and linearly varying to 50mm at the centre, carries an effective prestressing force of 500 kN. Find the magnitude of the concentrated load Q located at the centre of span when the load counteracts the bending effect of prestressing force (neglect self weight)(in kN)
250 mm contains tendons of area 500 mm2 at centre of gravity of the section. The pre-stress in the tendons is 1000N/mm2.Assuming modular ratio as 10.the stress in(N/mm2) concrete is 
