No abstract

A study of the behavior of fibers in high-strength reinforced concrete beams is presented in this paper. Twelve reinforced concrete beams were tested under a pure torsion load. Different compressive strengths (45.2, 64.7, and 84.8 MPa) and fiber volume fractions (0, 0.25, 0.5, and 0.75) with variable spacing between transverse reinforcements have been used. It was discovered that the maximum torque of a high-strength concrete beam is increased by about 20.3, 25.6, and 27.1% when the fractional volume of fiber is increased from 0 to 0.25, 0.5 and 0.75 respectively (when the compressive strength is 45.2 MPa and the transverse reinforcement spacing is 100 mm). The test results show that the ultimate torsional strength becomes higher when the concrete compressive strength increases, and this percentage increase becomes higher with increasing steel fiber volume fraction. When the spacing between transverse reinforcements decreases from 150 to 100 mm, the ultimate torque increases by 19.9%. When the spacing between transverse reinforcements decreases from 100 to 60 mm, the ultimate torque increases by 17.0%. In these beams, the fibers’ compressive strength and volume fraction were kept constant at 45.2 MPa and 0.75, respectively. Doi: 10.28991/CEJ-2022-08-01-07 Full Text: PDF

The effect of web openings in steel girders were investigated experimentally by testing six girders under two point loads with circular, square and rectangular opening webs. The last girder was a plate girder with a solid web; however, similar dimensions were used for all girders. Results of experimental work revealed that girders’ critical buckling decreased with increases in openings sizes, also depending upon the shape of the opening. Also, theoretical equations were initiated due to elastic local buckling and compared with experimental. Both experimental and analytical work was adopted to carry out the numerical investigations of the structural response of the girders with different shape of holes by using ANSYS (version 12.0). SHELL 181 was utilized to create the steel plate. Finite element model adopted though out the parametric study to investigate the critical buckling of plate girder with different web width ratios and slenderness ratios to determine the effects of changing size and shape for different web width and slenderness ratio.

No abstract

No abstract