| Title |
Review of Steel ratio Specifications in Korean Highway Bridge Design Code (Limit States Design) for the Design of RC Flexural Members |
| Authors |
이기열(Lee, Ki-Yeol) ; 김우(Kim, Woo) ; 이준석(Lee, Jun-Seok) |
| DOI |
https://doi.org/10.12652/Ksce.2017.37.2.0277 |
| Keywords |
균형철근비;도로교설계기준(한계상태설계법);최대 중립축 깊이;최대철근비;극한한계상태 Balanced steel ratio;Korean Highway Bridge Design Code (Limit States Design);Maximum neutral axis depth;Maximum steel ratio;Ultimate limit states |
| Abstract |
This paper describes the specifications on balanced steel ratio and maximum reinforcement for the design of RC flexural members by the Korean Highway Bridge Design Code based on limit states design. The Korean Highway Bridge Design Code (Limit States Design) is not provide for the balanced steel ratio specification for the calculation of required steel area of RC flexural members design. The maximum steel area limited the depth of the neutral axis at the ultimate limit states after redistribution of the moment, and also recommended the maximum steel area should not exceed 4 percent of the cross sectional area. However, from the maximum neutral axis depth provisions should increase the cross section is calculated to be less the maximum reinforcement area, and according to the 4% of the cross sectional area of the concrete, the tensile strain of the reinforcement is calculated to be greater than double the yielding strain, so can not guarantee a ductile behavior. This study developed a balanced reinforcement ratio that is basis for the required reinforcement calculation for tension-controlled RC flexural members design in the ultimate limit states verification provisons and material properties and applied the ultimate strain of the concrete compressive strength with a simple formular to be applied to design practice induced. And assumed the minimum allowable tensile strain of reinforcement double the yielding strain, and applying correction coefficient up to the ratio of maximum neutral axis depth, proposed maximum steel ratio that can be applied irrespective of the reinforcement yield strength and concrete compressive strength. |