Reinforced concrete structural elements with box section are commonly used in the horizontal and vertical structure of bridges. The reinforced concrete structure in bridge often failed under the combined forces of ben...Reinforced concrete structural elements with box section are commonly used in the horizontal and vertical structure of bridges. The reinforced concrete structure in bridge often failed under the combined forces of bending, axial load, shear and torsion caused by wind and earthquake. It is very important to study the mechanism of RC box section structures subjected to a combi-nation of forces. A theoretical study and deduction of the unified expression for failure of reinforced concrete members with box section under combined bending, shear, axial force and torsion were carried out with stress equilibrium assumption. Comparison of theoretical analysis results with experimental results showed that the unified expression for failure of reinforced concrete members with box section can be used for static calculation of such structure members.展开更多
In order to investigate the compression creep of two kinds of high-performance concrete mixtures used for prestressed members in a bridge,an experimental test under laboratory conditions was carried out.Based on the e...In order to investigate the compression creep of two kinds of high-performance concrete mixtures used for prestressed members in a bridge,an experimental test under laboratory conditions was carried out.Based on the experimental results,a power exponent function was used to model the creep degree of these high-performance concretes(HPCs) for structural numerical analysis,and two series parameters of this function for the HPCs were given with the optimum method of evolution program.The experimental data were compared with CEB-FIP 90 and ACI 92 models.Results show that the two code models both overestimate the creep degree of two HPCs,so it is recommended that the power exponent function should be used for the creep analysis of bridge structure.展开更多
基金Project supported by the National Basic Research Program (973) of China (No. 2002CB412709), and the National Natural Science Foundation of China (No. 50378054)
文摘Reinforced concrete structural elements with box section are commonly used in the horizontal and vertical structure of bridges. The reinforced concrete structure in bridge often failed under the combined forces of bending, axial load, shear and torsion caused by wind and earthquake. It is very important to study the mechanism of RC box section structures subjected to a combi-nation of forces. A theoretical study and deduction of the unified expression for failure of reinforced concrete members with box section under combined bending, shear, axial force and torsion were carried out with stress equilibrium assumption. Comparison of theoretical analysis results with experimental results showed that the unified expression for failure of reinforced concrete members with box section can be used for static calculation of such structure members.
文摘In order to investigate the compression creep of two kinds of high-performance concrete mixtures used for prestressed members in a bridge,an experimental test under laboratory conditions was carried out.Based on the experimental results,a power exponent function was used to model the creep degree of these high-performance concretes(HPCs) for structural numerical analysis,and two series parameters of this function for the HPCs were given with the optimum method of evolution program.The experimental data were compared with CEB-FIP 90 and ACI 92 models.Results show that the two code models both overestimate the creep degree of two HPCs,so it is recommended that the power exponent function should be used for the creep analysis of bridge structure.