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The aim of this research work is to study the most important parameters that affect the loading capacity and behavior of elliptical ring reinforced concrete beams with (L) section. Twenty specimens were modelled using ETABS Software to study the effect of changing the length of the major axis (while keeping the ratio of the major to minor axis equal to 0.64), width, height, thickness, and loading type. The maximum values of negative bending and torsional moments in addition to midspan deflection increase by 1.24-8.24%, 1.33-11.43%, and 32.5-131%, respectively when the major axis of beam increases by 20-60%. Whereas, major axis increase leads to decrease the maximum positive bending moments and load capacity by 5.91-4.45% and 26.5-52.9%, respectively. That happens due to the extending of span length that happened because of major axis increase. When the beam height increases by 25-75%, the maximum positive and negative bending moments (M+ve) and (M-ve), torsional moments and load capacity increase by 33.92-102.4%, 33.92-100%, 29.84-89.74% and 38.8-116.6%, respectively. While this increase in height leads to maximum deflection decrease by 5-8.4%. That happens because the beam sectional area increases due to increasing beam height. M+ve and M-ve, load capacity and midspan deflection decrease by 0.33-7.9%, 1.61-1.1%, 4-20%, and 11-30%, respectively when beam width increases by 46.6-140%. While this increase in width leads to torsional moment to increase by 2.15-0.87%. The sectional area of beam increases because of width increase, i.e., additional strength capacity. When thickness of beam increases by 100-500%, M+ve, M-ve, load capacity and maximum deflection decrease by 4.25-18.8%, 2.3-16.2%, 7.4-37% and 19.8-67%, respectively, whereas the torsional moments increase by 1.42-0.12%. Finally, torsional moments increase by 0.68-1.49 %, respectively due to testing through partial or full uniform load by 20-100% length of span. [ABSTRACT FROM AUTHOR]

The current work presents a study on strength and behavior of reinforced concrete T-section elliptical ring deep beams through the finite element technique. The parameters that were taken into consideration are diagonal axis (major axis) with the same major axis to minor axis ratio, height, flange thickness, web thickness, and compressive strength of concrete. It is found that the maximum values of positive bending moment (Mmax+ve), maximum negative bending moments (Mmax-ve), maximum torsional moments (Mmaxtor) and deflection increase by about 0.12-0.77%, 1.86-4.9%, 1.9-3.77% and 22.7-77.9%, respectively when the beam diagonal axis increases by 16-50%. Mmax+ve, Mmax-ve, Mmaxtor and load capacity increase by about 68.43-135.3%, 71.13-142%, 61.89-123.8%and 71-142%, respectively when the beam height increases by 50-100%. While the increase in height leads to decrease in the maximum deflection by about 4.62-5.33%. Mmax+ve, Mmax-ve, load capacity and max deflection decrease by about 0.38-4.04%, 1.135-6.25%, 1.51-6.06%, 13.5-30.9%, respectively when the flange thickness increases by 100-200%. While the increase in flange thickness leads to increase in the Mmaxtor by about 0.57-0.42%. Mmax+ve, Mmax-ve, Mmaxtor, load capacity and max deflection increase by about 210.4-446.8%, 156.63-374.9%, 216.5-494%, 215.4-469.2% and 82.4-129.8%, respectively, when concrete web thickness increases by 50-100%. Mmax+ve, Mmax-ve, Mmaxtor, load capacity and max deflection increase by about 15.69-42.49%, 15.78-41.62%,15.81-41.7%, 16.92-44.61% and -0.37-0.37%, respectively, when concrete compressive strength increases by 33.33-100%. [ABSTRACT FROM AUTHOR]

This paper displays the horizontal curvature (circular curvature) effect on deep beams using finite element analysis. Thirty-five reinforced concretes horizontally arched deep beams were analyzed. The parameters that were taken into consideration in the current work are the curvature angle (α) and beam height (H) while keeping one constant value for the beam length (L), i.e., different length to depth ratios (L/H). It is found that for L/H=2; the load capacity decreases by about 38-73% and 16-67%, respectively, when changing α from ∞ (straight beam) to 180 degrees, while torsional moments increase by about 74-174%. Negative bending moments decrease by about 13-56% when changing α from 30 to 180 degrees. The deflection decreases by about 0.1-1.8% when changing α from ∞ to 90 degrees. For L/H=2.5; The load capacity decreases by about 36-73% and 15-67%, respectively, when changing α from ∞ to 180 degrees, while torsional moments increase by about 73-168%. Negative bending moments decrease by about 14-57% when increasing α from 30 to 180 degrees. Decreasing deflection by about 4.1-5.9% when increasing α from 60 to 90 degrees. For L/H=3; load capacity decreases by about 34-73% and 14-68%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 71-161%. Negative bending moments decrease by about 15-58% when increasing α from 30 to 180 degrees. The deflection decreases by about 6-9.7% when increasing curvature angle from 60 to 90 degrees. For L/H=3.5; the load capacity decreases by about 34-73% and 14-69%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 70-156%. Negative bending moments decrease by about 15-59% when changing α from 30 to 180 degrees. Midspan deflection decreases by about 4.6-14.7% when changing α from 60 to 120 degrees. Finally, it is found that for L/H=4; The load capacity decreases by about 33-74% and 14-69%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 69-150%. Negative bending moments decrease by about 16-60% when changing α from 30 to 180 degrees. Changing α from 60 to 120 degrees leads to decrease deflection by about 9.1-19.4%. [ABSTRACT FROM AUTHOR]

The current work presents a parametric study for twenty-five reinforced concrete overhang curved deep beams using finite element analysis. The parameters that were taken into consideration are radius, height, width, compressive strength of concrete and number of supports. It is found that the max positive moments increase by about 2.8-4.4% when decreasing the radius of beam by about 16-33%. The max negative bending moment, max torsional moments and max deflection decrease by about 1.9-12.4%, 0.4-8.9% and 30-87%, respectively, when beam radius decreases by 16-66%, whereas load capacity increases by about 23-195%. The max positive bending moment, max negative bending moment, torsional moment and load capacity increase by about 32-128%, 30-124%, 31-125% and 31-127% respectively, when the beam height increases by 12.5-100%, while deflection decrease by about 9-18%. The max positive bending moment, max negative bending moment, torsional moment, load capacity and max deflection increase by about 32-147%, 29-134%, 30-138%, 32-146% and 1.2-4.9%, respectively when beam width increases by 12.5-50%. The max positive bending moment, max negative bending moment, torsional moment, load capacity and max deflection increase by about 17-70%, 15-61%, 15-63%, 17-69% and 0.1-0.4%, respectively, when concrete compressive strength increase by 33-166%. Finally, it is found that the max positive bending moment increases by about 32% when increasing number of supports by 33%. Max negative bending moment and capacity of load increase by about 17-60% and 106-763%, respectively, when number of supports increases by 33-133%. Torsional moment and max deflection decrease by about 0.8-16% and 29-78%, respectively when number of supports increases by 33-133%. [ABSTRACT FROM AUTHOR]