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.
Slabs are considered one of the most exposed elements to disasters and deformities
that can be clear to the viewer. These deformities are reflected as sign of defects that
appear clearly on big slabs. So, here comes the importance of applying and d
esigning
accurate slabs.
The purpose of this research is stating the need for persistent efforts to get a better
form of the slabs in order to increase their ability to be able to carry any outside extra
weights without the appearance of any deformities that might take place during the period
of investing the building. When deformities happen, they have bad effect on the beauty
and main function (purpose) of the building.
This research includes an experimental study for the real applicable slabs under our
supervision, in addition to a theoretical study about the deflection appearing on the slabs
by taking into consideration the plastic specifications of the concrete and the formation of
cracks.
This research aims at constructing reflexive deflections in the slabs during the
construction period and measuring the actual deformities and watching them through a
period of time, then comparing them with the theoretical expected deformities.
The findings that we could get at the end of our research are supposed to play a main
role in choosing the best design for the mandate slabs and at the same time getting the best
value for the reflexive deflection that can be used in the slab to make it better functionally
and to increase its ability to resist the outside applied weights. We hope this is just a start
for more research in this field.
يعالج البحث إمكانية حساب السهوم في العناصر الخطية المنفذة من البيتون المسلح بتأثير
الأحمال طويلة الأمد ( بقيم ثابتة أو متزايدة ) وفقاً لطريقة المستقيمين المقترحة في بحث
سابق من أجل الأحمال اللحظية.
