الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
(1) Both the change in main steel position and increasing the flange width have no significant effect on mode of failure However, increasing the percentage of additional reinforcement changed the mode of failure from tension failure to compression failure.
(2) Presence of steel reinforcement outside the beam web (in the adjacent slab) will result in decrease the number of horizontal cracks in the top surface of the flange in comparison with beams having all steel reinforcement in the web (no external reinforcement). Also increasing percentage of additional reinforcement decreases the number of horizontal cracks in the top surface of flange.
(3) The values of cracking load generally improved by increasing the flange width either increasing the percentage of additional reinforcement to main steel. While, increasing the percentage external steel to main steel reduced the values of cracking load.
(4) Increasing the percentage of external steel to main steel may lead to decrease the ultimate load with small values. However, increasing the flange width has no significant on ultimate load. Increasing the percentage of additional reinforcement has beneficial effect on increasing the ultimate load.
(5) Increasing the percentage of external reinforcement causes an increase in the central deflection values while, both increasing the flange width either increasing the percentage of additional reinforcement increased the stiffness of beams; central deflection decreased.
(6) The ratio between cracking and ultimate loads (Pc/Pu) resulted from testing beams ranges from 26 % to 40 % compared with the known ratio of beams failed under flexural stress (30-40 %).
(7) Increasing the percentage of external reinforcement may lead to increase the strain in internal steel and decrease the strain in external steel. While, Increasing the flange width has no significant effect on strain in internal and eternal steel. However, increasing the percentage of additional reinforcement reduces the strain in main steel.
(8) Up to 50 % of main steel were furnished in the web , the strain over the web was higher than the strain over the flange, more than this percentage, the strain distribution over the web was lower than the strain over the sides of the flange
(9) Change in main steel position from the web to the flange has beneficial affects in decreasing the crack widths. At all stages of loading, maximum crack widths measured for beam with no external steel were more than those measured for all other beams with external steel. Also, increasing the percentage of additional steel to main steel has beneficial affects in decreasing the crack widths.