After pre-stressing process is completed, a loss of stress is due to A. Shrinkage of concrete B. Elastic shortening of concrete C. Creep of concrete D. All the above

Shrinkage of concrete
Elastic shortening of concrete
Creep of concrete
All the above

The correct answer is: D. All of the above

After pre-stressing process is completed, a loss of stress is due to shrinkage of concrete, elastic shortening of concrete, and creep of concrete.

  • Shrinkage of concrete is a decrease in the volume of concrete due to the loss of water. It is a time-dependent process that occurs after concrete has been placed and finished. Shrinkage can cause cracking in concrete if it is not properly controlled.
  • Elastic shortening of concrete is a decrease in the length of concrete due to the application of stress. It is a reversible process that occurs when the stress is removed. Elastic shortening is usually small compared to the other losses of stress that occur after pre-stressing.
  • Creep of concrete is a time-dependent increase in the strain of concrete under constant stress. It is a permanent deformation that occurs when concrete is subjected to sustained loads. Creep can cause a loss of prestress in prestressed concrete members.

The magnitude of the losses of stress due to shrinkage, elastic shortening, and creep depends on a number of factors, including the type of concrete, the curing conditions, the age of the concrete, and the magnitude of the applied stress.