Determine the stage of cracking moment of pre-stress, Civil Engineering

Determine the stage of Cracking moment of pre-stress

 At the stage of transfer of pre-stress in the pre-stressed beam element, only the pre-stressing force and the self weight of the beam may be assumed to act. At this stage, the beam soffit (bottom side) may be assumed to be under compression as the stresses, due to self weight only, are of low magnitude. As the extenal imposed loads are applied on the beam, the compressive stresses (due to pre- stressing) shall decrease due to the tensile stresses generated by external loads. A time comes when these stresses of opposite nature balance each other. At this stage, the soffit of the beam shall be subjected to zero stresses. If extenal loads are further increased, the soffit of the beam shall come under tension. At a particular value of tensile stress the concrete at the location of the soffit of the beam shall crack and visible cracks appear. This tensile stress, at this stage, may be taken to be equal to the modulus of rupture of concrete. The visible cracks have crack widths of the order of 0.01 - 0.02 mm.


Posted Date: 10/5/2013 2:23:02 AM | Location : United States

Related Discussions:- Determine the stage of cracking moment of pre-stress, Assignment Help, Ask Question on Determine the stage of cracking moment of pre-stress, Get Answer, Expert's Help, Determine the stage of cracking moment of pre-stress Discussions

Write discussion on Determine the stage of cracking moment of pre-stress
Your posts are moderated
Related Questions
Dead weight Dead loads are the weight of permanent components of the structures such as the weight of the elements and spheres, casing weight, weight of the false ceiling a

I am a Civil Engg student. Why CBR Values determined only at 2.5 and 5 mm penetration ?.

Q. What is Shock transmission unit in bridges? Shock transmission unit is fundamentally a device connecting separate structural units. It's characterized by its ability to tran

A rectangular concrete beam is subjected to a factored design shear force of 200 kips.  For the beam shown below, determine the required stirrup size and spacing requirement. H = 3

how many types of drainage galleries and foundation treatment

Q. Evaluate the Length of guide bund? For encouraging axial flow through the bridge, upstream length of guide bund may be kept 1.0 to 1.5 times the bridge length and downstream

Water Transportation: Water transport, in its various forms, is one of the most efficient forms of transport, because of low fuel consumption, low environmental pollution and

difference between delievery and suction pipe?

Design a Cylindrical Open Caisson to be sunk by 30 m of sand to support a load of 50 MN. The allowable bearing pressure is 1700 kN/m 2 . Test the feasibility of sinking the caisson