الفهرس 
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Abstract
Self-compacting concrete (SCC) is a new generation of special concrete,
where no inner or outer vibration is necessary needed for compaction. The use
of SCC is recommended for all applications of civil engineering sector, where
the mentioned advantages are necessary to assure a good concrete quality,
especially in highly reinforced concrete members like tunnel segments.
This thesis presents the results of an experimental investigation for using
SCC in thin sections, like hollow sections. Also, thesis introduce a new
construction technique for using these hollow sections as tunnel segments
which are alternative construction to passing bridges to decrease problems
which happened in highway roads because of the difficulty of using passing
bridges especially for children and old people. The main objective of this thesis
is to study the flexural behavior of reinforced hollow beams casting with SCC.
The main variations were: shape of sections (square and circle), thickness of
cross , reinforcement type (ordinary steel bars -welded
mesh-expanded mesh), concrete cover thickness (1.5 cm and 2 cm) and
number of reinforcement mesh layers (one layer and two layers). In this
method, steel meshes are used as a viable alternative to ordinary steel bars
commonly used in reinforcing concrete beams. Fourteen reinforced concrete
hollow beams were casted and cured for 28 days before testing. The
dimensions of hollow beams with square cross section were 40*40cm for outer
dimensions and inside dimensions 28*28 cm, thickness 6cm and length 150 cm.
the dimensions for circular diameter and
28 cm for inside diameter , thickness 6cm and length 150 cm . We decreasing thickness to 4 cm when using steel meshes .Theoretical analysis conducted by
developing a computer program (Ansis 15) as a package of finite element
analysis to verify the behavior of the tested specimens. The results of both
experimental and analytical investigation are to examine the effectiveness of
this method and present the results showing samples reactions including the
cracking patterns, deformations and strength characteristics of tested hollow
beams. The analytical and experimental results of hollow beams reinforced
with steel meshes emphasized that, ductility index and energy absorption
properties of tested beams were improved compared with the ordinary
reinforcement which give high quality in dynamic properties and better in
earthquake resistance. An application could be achieved by using the thin
hollow beams as precast units for construction tunnel sections that is
considering an alternative solution instead of passing bridges in highway roads.
This application is better in saving time instead of casting in the site and save
much money which need to establish alternative road. Because we can use the
same road without any stop period and avoiding traffic jam.