الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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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.