Civil Engineering Reference
In-Depth Information
Chapter 9
Conclusions
This thesis presents a comprehensive experimental program for analyzing the
behavior of FRC beams with different dimensions, production processes and
transverse reinforcement.
The analysis of the results conrms that steel bers improve the shear behavior
of beams and that their contribution may be highly bene
cial in many cases and
practically indispensable in others.
The main conclusions can be summarized as follows (subscript indicates the
chapter referred to):
A self-compacting
ber-reinforced concrete (SCFRC) of consistent quality can
be cast in a continuous process, as shown by the slump
fl
ow test, compressive
strength and
fl
exural behavior under normal site conditions (Chap.
4
).
Adding steel
bers to beams with stirrups improves ductility as steel
bers
With steel
bers more cracks are created but they are smaller than in plain
Beam
anges clearly improve shear behavior, as they prevent failure by com-
pression in the top beam layer. This effect should be included in the Codes in the
form of a
fl
fl
ange coef
cient (k
f
) for all types of concrete. An improvement in
shear behavior with
ange width was also observed, although there were two
exceptional cases with no improvements: small
fl
fl
ange widths (in relation to web
width) and large
ange widths (depending on the other dimensions of the cross
section) in which shear improvement remains constant over a certain
fl
fl
ange
width (Chap.
4
).
The RILEM approach does not model the positive effect of
bers on the dowel
action, as
bers do not affect
the longitudinal reinforcement
term, so that
RILEM considers
bers and longitudinal reinforcement to be completely
independent. On the other hand, MC2010 considers the positive effect of
bers
on the dowel action, so that the
bers
contribution increases with high longi-
'
Search WWH ::
Custom Search