الفهرس | Only 14 pages are availabe for public view |
Abstract This paper presents a proposed method for strengthening and repairing of reinforced concrete beams using ferrocement laminates as a viable alternative to steel plates and carbon fibers sheets which are directly glued to the cracked tension face of the beam by epoxy resins without shear connectors. The results of the experimental investigation to examine the effectiveness of this method are reported and discussed including strength, deflection, compressive and tensile strains, ductility ratio, Energy absorption properties and cracking characteristics of the strengthening and repairing of the reinforced concrete beams. Fifteen reinforced concrete beams were tested under four-point loadings until failure over simply supported 900mm span and having the dimensions of 50x100mm in cross section. The experimental program comprises three designations series. Series I include B1 control and B9 controls which conventional reinforced with steel bars and stirrups without and with polypropylene fibers, respectively. Series II consists of B2 -B8 which were repaired after failure with various types of metallic and nonmetallic reinforcing materials. Series III comprises B10-B15 which were strengthening with various layers of steel meshes while beam was strengthening with one layer of tenser mesh. The experimental results of the repaired beams emphasized that irrespective of the type of used meshes, expanded or welded steel mesh or the repair scheme, better cracking behavior for all test specimens could be achieved compared to their original behavior. Under short- term loading conditions, all repaired specimens restored more than their original ultimate strengths. The ductility ratio and energy absorption properties also improved by this proposed method of strengthening and repairing of beams by ferrocement. |