Prestressed Concrete Design, 1/e

Chapter 4

Losses in Prestress

4.1 Introduction

It is found that the prestressing force in prestressed concrete members decreases with time. Hence the actual prestressing force will not be equal to the initial prestressing force (P_i). This decrease in prestressing force is known as losses in prestress.

In the analysis of prestressed concrete members (Chapter 5), it is necessary to check the stresses in concrete at different loading stages like transfer loading stage and at service condition. Hence it is necessary to determine the losses in prestressing force at these stages.

The losses in prestressing force can be classified based on the time at which they occur. The losses that occur during the prestressing process are known as immediate losses ...