Issue34

I. Ivanova et alii, Frattura ed Integrità Strutturale, 34 (2015) 90-98; DOI: 10.3221/IGF-ESIS.34.09 93 Then the second strip of fabric is applied and a third coat of epoxy is rolled into the second strip of fabric. The epoxy is allowed to cure well before testing. a) b) Figure 2 : Details of bonding system of: a) Sandblasting of corbels and b) Application of carbon fiber on concrete surface by wrapping. Testing procedure With "Wishay measure" of 24 ways, all data of local strain of electric gauges are saved at different points of structure. All corbels are tested under three points blending load. So, at each test, strain of concrete, carbon fiber fabrics, steel bar and cracking system are noted. The measures of deformation are done at embedding section where strains are high. All tests are performed with a loading speed average of 0.2 kN/s. The data acquisition is recorded every 0.1 second. The maximum load capacity of bending test is 1000 kN. Firstly, the reference specimen without strengthening is submitted to a vertical load under static loading to collapse. This test enabled to determine the three specific areas: elastic area, crack propagation area and open diagonal crack area showed in Fig. 3. Knowing the load-strain curve, an average value of load is defined. This value is corresponded to average load in between 20 % to 40 % of maximum tensile strength. The magnitude and number of fatigue of the repeated loads are fixed to one million cycles. Figure 3 : Mechanical behavior of reinforced concrete corbel C0, strain of tensile steel bar.