Assessment,strengthening and validation of prestressed damaged beams
The paper describes the evaluation of the actual conditions,the repairing design criteria and procedures,and the final validation tests carried out on a severely damaged prestressed bridge in southern Italy.In the first phases several release tests have been performed on damaged and,for comparison,on sound beams,with the aim of evaluating the residual prestressing stress acting both on concrete and on tendons.In particular,the tests on concrete have been carried out by extracting cores which have been previously instrumented with strain-gages;in a similar way,the strands were tested by gluing a micro strain-gage on a singular wire of a strand and the cutting the wire itself.The test results were used for optimising the design of an adjunctive prestressing system,consisting in 6 external unbounded cables and in a continuous FRC reinforcing of the bottom wing.The tensioning procedure of the external cables of each beam was then monitored by means of 12 strain-gages installed on concrete at mid span and at the two support sections,and by measuring the vertical deflection using laser optical levels.The validation of the repairing works was finally performed by a static load acceptance test,performed using the same apparatus previously adopted for the tensioning monitoring.
Ezternal prestressing FRC in situ release tests static and dynamic acceptance tests
Lucio Delia Sala Rosario Cerone Alberto Gennari Santori MauroTommasini
Università della Basilicata,Potenza Studio di Ingegneria-Melfi (PZ) CND Controlli Non Distruttivi s.r.l.Roma CND Controlli Non Distruttivi s.r.l.-Roma
国际会议
The 8th International Conference on Damage Assessment of Structures(DAMAS 2009)(第八届结构损伤评价国际学术会议)
北京
英文
359-366
2009-08-03（万方平台首次上网日期，不代表论文的发表时间）