الفهرس 
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Abstract
Reinforced concrete structures most frequently contain
lap splices. Splices take place because of the length of
the reinforcing bars, which produced normaly in a standard
dimensions. In general, bars are cut to a shorter lengthes,
and lapped, mostly, at the location of minimum bending
moments.
The forces in the spliced bars are transmitted,
as normal, to the concrete by bond. The classical concept
of bond is that it consists of adhesion between the
reinforcement and the surrounding concrete, and the bond
failure is caused by the failure in this adhesion.
Traditional design methods and code provisions concerning
bond and anchorage of reinforcement are based upon this
concept and result in provisions for allowable bond stress
values or corresponding development length necessary for
developing the full design strength in the bars.
The confining of concrete by using stirrups, improves
the bond resistance by improving the properties of concrete at the regions of splices. Moreover, the stirrups
across the longitudinal splitting cracks decrease this
splitting, and hence restrain the width of crack.
However, most national building codes disregard the effect
of the lateral confinement of concrete on the