Document Type : Research Paper
Authors
1 Civil EngineeringDepartment, University of Technology - Iraq
2 Civil Engineering Department, University of Technology - Iraq
Abstract
The use of recycled concrete aggregates (RCA) to replace part or
all of the natural coarse aggregates (NCA) in the production of concrete
has been on the increase. Such use helps in the protection of the natural
resources and in the reduction in the use o
f landfills.
The experimental
work consists of casting and testing ten rectangular simply supported
reinforced concrete beams of dimensions (1500*150*240) mm with
concentric point load at mid span as well as tests for control specimens to
determine the mechanical prope
rties of the concert. Five beams of these
ten beams were designed to fail in flexure and other five beams were
designed to fail in shear. Two beams were considering as a reference
beams using normal aggregate (NCA) and two beams were considering as
a refer
ence beams using recycled aggregate (RCA. The other six beams
were cast using recycled concrete aggregates (RCA) with steel fiber in
three different volumetric ratio (vf).The present investigation contains
three main variables: Coarse aggregate (normal and
recycled).
Transverse
reinforcement (with stirrups spacing 50 mm for flexure failure mode and
without stirrups for shear failure mode). Steel fiber (vf) = (0.5) %, (1) %
and (1.5) %.
In addition, constant longitudinal reinforcement ratio 0.012
.
Experiment
al results have generally showed that ultimate loads (Pu) of
beams made with RA are approximately close to the results of beams made
with NA but with decrease of values (14% and 21%) for flexural and shear
behavior respectively.
The ultimate load of fibrou
s concrete beams is
greater than beams without steel fiber by
(33%
-
50%) for shear behavior
and
(21%
-
35%) for flexure behavior.
Keywords
- Normal aggregate concrete (NAC)
- Recycled aggregate concrete (RAC)
- Normal coarse aggregate (NCA) Recycledcoarseaggregate (RCA)
- volumetric ratios of steel fiber (vf)
Main Subjects
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)
