الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 195 |  |  |
| | | from | 195 | | |
Abstract
One of the challenges of the current era is reaching a compatibility between the required resistance and lightweight for structural elements. The utilization of the lightweight materials may negatively affect the mechanical properties. Therefore, the fiber was used based on its optimal solutions to enhance the materials and contributes to improve the mechanical properties. Although the fibers Industrial such as carbon and glass is the most common, as it gives a high tensile resistance, the production of these fibers is energy-consuming, costly and causes negative effects on the environment.
Therefore, researchers tend in recent years to search for other types of fibers that are environmentally friendly and low cost. Therefore, the trend has been towards plant fibers, as banana fibers, because it can be obtained easily, low-cost, environmentally friendly and give distinctive mechanical properties.
The use of banana fibers in composites and concrete is a new technology that is economical, low-cost, environmental and recyclable. Having banana fibers with a high percentage of cellulose made it more suitable for the industrial structural purpose in building and construction materials.
The general objectives of this study are to investigate the effect of banana fibers on the flexure behavior of RC beams. Flexural strength results from the tested beams showed an increase in flexural strength depending on the fiber ratio.
The present thesis studied the behavior of reinforced concrete beams reinforced with banana fiber reinforced polymer bars (BFRP). This was achieved by conducting an experimental program and numerical study.
In the first part of the thesis, a full description of the experimental program is given where forty simply supported beams were tested under monotonic static concentrated loading. All specimens had identical central span length of 1000 mm, concrete depth 250 mm, concrete width 200mm. The test specimens were varied according to: (1) banana fiber bars ratio, (2 )
concrete strength, and (3) hybrid composite ( glass + banana ) fiber bars compared with glass fiber bars.
In the second part of the thesis, test results are compared to the predicated finite element analysis using ANSYS 14 program where a well agreement achieved between the experimental and numerical results.
9.2 Conclusions
Based on the experimental program and the numerical study that were conducted in this study on the reinforced concrete beams reinforced with banana fiber bars, the following conclusions may be drawn:
1. It is important to convert the waste materials that came from banana fiber to a new source that can be used in small construction building, temporary building, and caravans.
2. Banana fibers are waste product of banana cultivation, therefore there is no any additional cost and it has economic effect when it was used in construction purpose by reducing the cost compared to the traditional steel bars.
3. Banana fibers as a reinforcement for concrete beams give more flexural strength compared to plain concrete by about 25%.
4. The ratio of the ultimate strength of the beams reinforced with banana fiber bars and that reinforced with mild steel and high tensile steel is 57% and 18%.
5. The banana fiber in the hybrid composite section plays a beneficial contribution to the performance of the beams and bonding between the hybrid bars and concrete is reliable. The banana contributed enhancement in load carrying capacity of beams and contributed with 75% of the load carrying by glass fiber bars with doubled elongation and also contribute in reducing the cost.
6. The concrete strength has small impact on the ultimate load at failure of the concrete beams reinforced using banana fibers bars because the failure is due to rapture of the Banana fiber bar.
7. The cost of using BFRP bars as main reinforcement in a beam is lower than that reinforced with steel bars with 88.3%,70.5% and 26% when providing the same area, strength and stiffness of bars
8. The predicted numerical results from ANSYS program for loading and deflection at ultimate and first cracking levels, show a good agreement with the experimental results.
9. The simulated cracking patterns and failure modes are nearly similar to the testing results for all beams.
10. The average ratio between measured load and predicted load is 1.2% at ultimate level.
11. The average ratio between numerical and experimental ultimate deflection values is
11% This is due to the assumption of full bond between reinforcing steel and concrete and also the numerical analysis hasn’t descending branch.
9.3 Recommendations for Structural Engineers
1- It is recommended to use banana fiber bars in structure elements due to its low cost and eco- friendly compared to the use of other type of synthetic fiber;
2- Banana fiber bars can be used in the economical and temporary building because urgent need to develop suitable and affordable housing.
3- Banana fiber bars can be used instead using of steel bars to reduce corrosion.
4- It is suggested that hybrid epoxy composites can be used as an alternate material for synthetic fiber reinforced composite materials
9.4 Suggestions for Future Studies
For best understanding of the behavior of reinforced concrete beams reinforced with banana fiber bars in flexure, the present experimental and theoretical research works can be extended to the following points to cover the points that did not studied in this work:
1. Study the behavior of banana fiber with tensile strength more than 360 MPa and study its flexure behavior;
3. Study the performance of banana fiber in the shear strength;
4. Study the behavior and the performance of hybrid fiber using banana fiber bars;
5. Study the behavior and the performance of banana fiber bars in the slabs; and
6. Study the effect of fatigue loading on concrete beams reinforced with banana fiber bars.