الفهرس 
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Abstract
The scope of this research work was to present analytically a throughout study of reinforced concrete deep beams with different geometrical and loading configurations using finite element (FE) analysis software to present an equation that can be used as a guideline in designing the deep beams which have effective length to thickness (1.25 L/t 4 ).
For this purpose, a reinforced concrete deep beam model was calibrated using the FE software to experimental data provided in literature. Analysis results from validated model were compared to that obtained by experimental program to ensure that the elements, material properties, real constants and convergence criteria used in finite element modelling have captured the same behavior of experimental results from the literature. The use of ANSYS 16 to create the FE model is also discussed in detail.
For this purpose, a parametric study of forty-eight reinforced concrete deep beams were studied, the main parameter investigated in this study was (a/t) ratio, (L/t), longitudinal reinforcement, and web reinforcement. ANSYS 16 was used for the analytical study of all beams with same parameters and materials which used in the calibration model.
7.2 Conclusion
The results obtained from the parametric study using FE program (ANSYS 16) allows the following conclusions to be driven:
1. The validation model has proven the capability of the model to capture and monitor load capacity, the shape, and propagation of cracks till failure.
2. The deep beams’ failure was mostly because of the diagonal cracks which joining the point loading with the support which defined as a compression strut.
3. It was observed that the smaller span to depth ratio (L/t), the higher shear strength value.
4. Based on ANSYS 16.0 software, the failure load of deep beams increase with the increase of compressive strength of concrete.
5. The effect of changing compressive strength of concrete from moderate strength (40 MPa) to high compressive strength (100 MPa) for beams which have shear span to depth ratio (a/t) less than or equal to 1 caused an increase in failure load by about 250% for reinforcement ratio(As%) greater than or equal 1%. On the other hand for beams which have shear span to depth ratio (a/t) less than or equal to 2 an increase in failure load by about 10% to 25% was observed.
6. The web reinforcement have a low effect on the failure load for beams with a/t 1 as the failure load decreased by about 10% 15% and at a/t=1.5 with As%=1.5% with very high compressive strength Fcu =100 MPa the failure load decreases by about 20%. The web reinforcement is helpful to prevent the propagation of the inclined cracks.
7. The shear span to depth ratio (a/t) has a large effect on the beams’ capacity as decreasing (a/t) from 2 to 1 causes a duplicate in failure load at a moderate strength of concrete, three times and half at a very high compressive strength of concrete. Decreasing (a/t) from 2 to 0.67 at moderate compressive strength of concrete causes an increase in capacity by about 6 times and at very high compressive strength causes an increase in the capacity by about 7 times and half.
8. The higher of reinforcement ratio, the higher shear strength value is.
9. Based on the results of the parametric study from ANSYS 16.0 software, a relationship was driven using statistical method from the abovementioned parameters which were affected on the capacity of the beams to be used as guideline of the design of deep beams with the same limit of this research
7.3 Recommendations for future studies
The following are some suggested topics for further research in the study of the deep beams;
1. Studying the Beams under uniformly distributed load as most of the previous researches and in this research were tested under symmetrical two-point loads or one-point loads.
2. Comparing analytical values of deep beams subjected to concentrated load with that subjected to uniform distributed load and explain what is useful.
3. Changing the load location on the beams to be in the middle or in the bottom of the beams.
4. Studying the deep beams behavior of more than one span as most of the researches and codes were collected their data from the simple beams.