DUGi

Analysis and experimental measurement of losses in prestressed concrete : definition of a procedure

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@259648

Prestressed concrete has become a crucial part in the current architectural and civilengineering world. It is used to produce beams, bridges, floors … Due to the prestressingforce these concrete elements can withstand high loads. The ability to cover larger spansthan any other regular reinforced concrete parts has been a milestone in today’s engineeringpossibilities. To maintain this ability it is very important that the compressive stresses insidethe element are controlled.When applying a prestressing force to a concrete element it is necessary to take intoaccount that losses will occur, which will decrease the prestressing force. The measurementof these losses in on-site conditions usually is performed in a very elementary way. In thisthesis a more accurate and efficient way to measure the compressive stresses and prestresslosses inside the element is defined.The objective is to create an autonomous, automatic and remote data acquisition system. Tosupervise the stresses strain gauges will be attached to the prestressing cables. With thestrain gauges the strain in the strand(s) can be measured. The strain is sent to a remoteserver through the acquisition system, where it can be used to analyse the stresses.First the state of the art is analyzed. The general idea where the problem will be defined anda solution is proposed will then be discussed, followed by the design of a special ductelement created to protect the strain gauges. In the next chapter the design of the steelelements is discussed, which are needed to execute the tests. Finally the study, executionand analysis of the tests are described in the case study. To end a general conclusion is madeand further research is proposed