Evaluation of strengthened reinforced concrete beams: Cyclic load test and acoustic emission methods

Two different nondestructive evaluation procedures, the cyclic load test method and acoustic emission method, were compared for strengthened reinforced concrete beam specimens. The cyclic load test method is a proposed alternative to the existing 24-hour load test procedure. It makes use of a prescribed loading pattern and evaluation criteria of permanency, repeatability, and deviation from linearity. Evaluation by acoustic emission is a developing method that likewise makes use of prescribed loading procedures. An evaluation criterion or the acoustic emission method was developed and is described. The results obtained by both methods are discussed. A total of six beams were included in the investigation-two unstrengthened beams, two beams strengthened with precured strips, and two beams strengthened with unidirectional fabric.