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ABSTRACT
Textile reinforced mortar that has developed in recent years is composed
of the continuous textile fabric incorporated into the cementitious matrix.
The excellent characteristics of the textile reinforcement such as high tensile
strength, high modulus of elasticity and bond nature with the mortar
promotes the use of this type of reinforcement instead of the steel
reinforcement or with the steel reinforcement in reinforcing the mortar.
In this thesis the experimental and analytical investigation is carried out
to study the flexural behavior of the textile reinforced and the composite
(steel and textile) reinforced one-way slab mortar. Twelve one-way slabs
with dimensions of (1500 500 50) mm were casted, cured and tested in
flexure. Eight of the tested slabs were reinforced with the textile carbon
fabric, one with steel reinforcement, one with chopped carbon fibers and two
slabs were reinforced with steel in combination with one and two textile
reinforcement layers.
The experimental results exhibited that the first crack load for the
composite (steel with one and two layers of carbon textile reinforcement)
slabs increased by (74.2% and 190%) respectively as compared with the slab
II
reinforced by only the steel reinforcement. As the load of steel reinforcement
yielding increased by (115% and 91.5%) and the ultimate load increased by
(66% and 103%) respectively as compared with the steel reinforced mortar
one-way slab. Furthermore, the crack width is reduced by (67% and 29.4%)
respectively at the cracking and at the final stage of loading. Furthermore,
the mode of failure is changed from the brittle to the ductile with the
combined textile reinforcement. However, increase the area of the textile
reinforcement by increasing the number of layers increases the ultimate load
by (32% 60.6%) and increase the mid span deflection at this point by
(18.7% 37.9%) while the bond factor is reduced by (9.6% 24.84%) with
the increase in number of layers. Moreover, the results showed that the
(66.67%) removing of weft yarns represents the optimal percentage of
removing since the cracking load and ultimate load were increased by
(15.85% and 40.72%) respectively, while the mid span deflection at the
ultimate load is reduced by about 6.09% as compared with the reference
textile reinforced mortar one-way slab. Furthermore, the cracks number and
the crack width have remained the same. The addition of the short carbon
fibers by (0.25% and 0.5%) leads to increase the ultimate load by
(24.19% 31.56%), bond factor by (24.69% 32.22%) while, the ultimate
deflection reduced by (11.96% 16.31%) as compared with the control
Textile reinforced mortar slab. The results exhibit the superior flexural
behavior of the slab that reinforced by textile carbon layers as compared with
the slabs reinforced steel reinforcement or short carbon fibers.
On the other hand, the results showed the mutual cooperative
contribution between the steel and textile reinforcement in bearing the
applied stresses. |
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