The research includes an analytical study using the finite element method for the reinforced concrete beams containing holes in the body. These tested trophies have a rectangular cross-section and without additional armament in the area of the hole,
and two patterns (patterned and simple support) were studied. As for the holes, they are rectangular in shape with variable dimensions, where prizes with one hole and prizes with two holes were chosen.
This research presents an empirical study about the behavior of High Strength Concrete
beams under the static cyclic loading. It determines the influence of cyclic loading on the
moment capacity and deflection of HSC beams. A comparison of the mome
nt capacity and
deflection in both kinds of loading (monotonic and cyclic loading) were achieved.
High Strength Concrete mixture was designed, based on the specifications of the American
code ACI 211.4R-93. Thirty six concrete beams were prepared, nine of them were tested
under monotonic loading and the rest of beams were tested under cyclic loading. The
cyclic loading was performed for (5,10,15) cycles, at a range from zero to 65%, 75%, 85%
of the minimum expected monotonic load.
The results showed that the cyclic loading have positive effect on the flexural behavior of
HSC members, whereas the moment capacity increased and the deflection decreased,
especially at a range from zero to 75% of the minimum expected monotonic load, when
the number of cycles was 5,10,15.
This work theoretically investigates the nonlinear behaviour of
reinforced concrete dee aimed topcantilever beams with concentrated loads
at their free ends The study is aimed to in investigate the behaviour
and respnse of such deep cantilever bea
ms, and to help structural
engineers to design and adopt appropriate reinforcement detailing of
such elements. A complete review of literature on this subject is
made.
Many techniques have been used in repair and strengthening of
reinforced beam, among which are external steel beams, external
pre- stressing, epoxy injection, additional concrete overlay, external
steel plates, additional longitudinal and transver
se - steel bars.
Fifteen R.C. beams were tested until failure and the deflection,
surface strains, internal steel strains, external steel strains and crack
patterns were measured, the results were analyzed and conclusions
were summarized. Finally, the recommendations were stated with
the needed future work.
This research deals with the minimum cost design of reinforced concrete T-beams
according to the Syrian code. The aim is to minimize the total cost of the beam while
respecting all the design requirements. Traditional method depend on a set of supp
ositions,
in the opposite this methodology aim to reach the optimal solution among a set of
constraints with respect the objective function. So that, using this methodology leading to
the minimum cost reinforced section design.
This research is shown that the problem can be formulated in a nonlinear
mathematical programming format.
Several cases are used to explain the applicability of the formulation in accordance
with the current Syrian code. Traditional method of Syrian code has been used to design
sections in this paper, utilizing the nonlinear programming method provided by Lingo14.0
software from LINDO Systems Inc. The comparison of the results shows that important
saving can be obtained at the total cost of a reinforced concrete T-beams design.
This research includes an experimental study and a nonlinear
analysis using the finite element method of reinforced concrete
beams with large opening in body that exist in shear zone . The
tested beams are simply supported with rectangular section
and
without additional reinforcement in opening region. The opening is
square in shape with variable dimensions and constant distance
from the support . Studying the effect of changing length of the
opening on the behavior of the reinforced concrete beams was
already completed. The modes of cracks , (load-deflection )
relationship, ultimate load and the mode of failure for all beams
were determinate . The study showed that existence an opening in
shear region of beams reduce the strength of beams and affect on
the mode of shear failure , and any addition in the depth of the
opening lead to early cracks , more deflections and less ultimate
failure load .
This research aims to study the efficiency of flexural strengthening of RC beams with different lengths of CFRP strips by using (NSM) technique. The study is carried out experimentally on (14) concrete beams; the variables considered are (the length
and number of CFRP strips). This is established by dividing the work into two groups: the first one includes (6) beams strengthened by variable carbon fiber strip lengths and one strip, The second group includes (6) beams strengthened by variable carbon fiber strip lengths and two strips, as well as two control beams. The results indicate that carbon fibers have a noticeable effect on increasing the bearing capacity of (NSM) strengthened beams. The results also show that strengthening the beams by CFRP and not along the length of the beam and in one layer does not contribute to increasing beam strength, but when the number of layers increases, an increase in beam strength is noticed at a rate range (40%-72%).
The horizontal Join beams with the slabs of reinforced concrete play the, the role of horizontal shear walls on the building height, Thus, the horizontal beams, columns and shear walls work together to form, the vertical resistance and horizontal loa
ds resulting from wind pressure or the intensity of earthquakes As a result to the great importance of the work of the join beams between wings of shear wall in the carrier wholesale of armed concrete، we have conducted experiments on shear wall and the result experiments compare with theory scientists and researchers in high- buildings. Been compared join beams with moment of stiffness constant in the level of its confluence with wings shear walls (Hold the forces of resistance horizontal dynamic plasticity in stage). And join beams in the form of crowns with moment of stiffness variable in the level of its confluence with wings shear walls.
We suggest a new theory with relationship for the change in the moment of stiffness join beams with crowns between wings of shear wall from reinforced concrete. Extract the experimental results and
compare them with the proposals of the new theory, and computational methods for global theories on the subject of search
And the impact of the work of the join beams with crowns between wings shear walls on the horizontal loads external pressure intensity of earthquakes or wind.
