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Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

U-shaped thin-walled RC beams are widely applied in urban railway transit in China. But research reference related to the calculation of ultimate bearing capacity of U-shaped beams under torsion and coupled effect of bending and torsion is extremely rare. A calculation model for evaluating the bearing capacity of U-shaped thin-walled RC beams was proposed on the basis of experimental results of six beams tested under pure torsion and bending-torsion. The principle of stiffness distribution and Vlasov' s theory for open thin-walled members were applied in the method. Six U-shaped RC beams were calculated by the method. And comparisons between calculated and test values of six tested beams validate the calculation model. [ABSTRACT FROM AUTHOR]

In calculation of the bearing capacity of the eccentrically loaded reinforced concrete columns, in order to consider the second order effect of bending moment in the section, the effect of bending moment enlargement coefficient is used, which includes two factors, i. e. the curvature influence coefficient of eccentricity ζ1 and the curvature influence coefficient of slenderness ratio ζ2. Some differences exist in the calculation methods of these two curvature influence coefficients among the current China design codes such as the GB 50010-2010 ' Code for design of concrete structure ' and JTG D62-2004 ' Code for design of highway reinforced concrete and prestressed concrete bridges and culverts'. Through the bearing capacity tests of 14 reinforced concrete columns, the column bearing capacities obtained from test results were compared with those calculated by code methods. The results show that the calculated bearing capacity of the specimens by the GB 50010-2010 are lower than the test ones due to the ζ2 is deleted in the code, while the calculation method of ζ1 in JTG D62-2004 is not rational since the calculated bearing capacities are larger than the test ones and tend to be unsafe for structures especially when the eccentricity is small. Based on the experimental research, parametric analyses by the finite element method were carried out, and the calculation formulas for ζ1 and ζ2 were proposed. The accuracy of the proposed calculation method was verified by the collected test results of the references. [ABSTRACT FROM AUTHOR]

Eccentric loading experiments of 13 steel tube-reinforced concrete columns (STRC), whose slenderness ratio was 4.67, were completed. Through testing the distribution of strain and stress of every part ( including core steel pipes, concrete inside and outside of pipes, longitudinal reinforcements) in the whole loading process, the bearing mechanism and failure feature of STRC were studied. Furthermore, using numerical nonlinear analysis, the influences of position coefficient, eccentricity and longitudinal reinforcement ratio upon bearing capacity were obtained. The study shows following conclusions. STRC columns subjected to eccentric compression are similar to reinforced concrete columns (RC), and the failure types are divided into large eccentric failure, small eccentric failure and limitation failure where the demarcation criterion is that the edge strain of concrete compression reaches the ultimate compressive strain as soon as the tensile steel yields. And its N-M curve is parabolic. STRC adheres to plane cross section assumption and its compressive reinforcements can always yield before the columns' failure without reference to its eccentricity. The bearing capacity of STRC is enhanced with the increase of position coefficient, but not by much, so the steel pipe can be selected only by considering its cross-sectional area and for the convenience of joints construction. Based on the test results, limit equilibrium theory can be used to deduce the normal section capacity formula of STRC columns by referring to that for RC columns. [ABSTRACT FROM AUTHOR]

This paper adopts near surface mounted prestressing helical rib steel wire system, using the process of slotting, reinforcing and tensioning helical rib steel wire, filling glue. An experimental study was conducted on 10 RC beams with near surface mounted prestressing helical rib steel wire. The experimental results indicate that this method can improve the overall performance of reinforced concrete beams. The first-crack load, flexural load, ultimate load are increased effectively. With various numbers of helical rib steel wire and prestressing levels, the first-crack load, flexural load and ultimate load can be increased by 72.6%-321.26%, 6. 19%-99.09% and 46.04%-135.27% respectively. This strengthening method can effectively improve the ductility, safety performance and stiffness of reinforced concrete beam. The emergence and development of cracks can be restrained, and the high strength of helical rib steel wire can be fully used. [ABSTRACT FROM AUTHOR]

Based on rational constitutive models of steel and concrete, load-deformation relationship curves of concrete-filled steel tube (CFST) reinforced concrete columns subjected to axial compression were calculated by the fiber model method and finite element method to investigate the behavior of composite column subjected to axial compression. The results of theoretical analysis are in good agreement with the experimental ones. Based on the research conclusion mentioned above, behavior analysis of concrete-filled steel tube reinforced concrete columns subjected to axial compression including failure mode, axial load distribution, and the interaction between outer concrete, steel tube and core concrete were carried out. Practical simplified formulae of bearing capacity were proposed, and results calculated using the formulae agreed well with test results. At last, it is suggested that in order to ensure the collaborating between outer concrete and inner concrete filled steel tube, the ratio of stirrup constraint index in outer concrete to constraint effect coefficient in inner concrete filled steel tube should not be less than 0. 188. [ABSTRACT FROM AUTHOR]

Tests of reinforced concrete (RC) members under the combined loading indicated that various kinds of bearing capacity would interact each other. However, the overall interaction of various force state is not considered thoughtfully in component design, leading to potential danger of structures. Using flexure-torsion interaction to connect shear-torsion and flexure-compression interaction, a unified formula was proposed in this paper considering the overall interactions of compression, shear, flexure and torsion. Every kind of interaction bearing capacity formulae can be deduced from the unified formula and easily used to determine the security of the member under various loading states. Experimental data were compared with the calculations of the proposed formula and good agreement was obtained. Finally, reinforcement obtained by the unified formula is more reasonable and more consistent with the experimental results compared with GB 50010-2002. [ABSTRACT FROM AUTHOR]

With quasi-static tests, the seismic performance of five kinds of shale ceramsite concrete shear walls were studied. The effects of height-width ratios and reinforcement ratios of shear walls were considered. The failure pattern, hysteretic loops, bearing capacities, ductility, energy dissipation, stiffness of shale ceramsite concrete shear walls were analyzed. Analytical result indicates that the shale ceramsite concrete shear walls have good ductility and mechanical properties. The height-width ratio is the major factor affecting the failure mode of shale ceramsite concrete shear walls. The failure mode of shale ceramsite concrete shear walls is similar to common concrete shear wall and other light weight aggregate concrete shear wall. The failed regions of shale ceramsite concrete shear walls mainly concentrate within the width of the shear walls on the bottom above. To increase the vertical reinforcement ratio will help improving the deformation properties and the bearing capacity of shale ceramsite concrete shear walls. To increase the transverse reinforcement ratio can not proportionally improve the bearing capacity of shear walls. Based on the analogous truss model calculation theory and the dowel actions of vertical reinforcement for shear wall, the calculation formula of the bearing capacity for shale ceramsite concrete shear walls was established and the calculate results were compared with test results. [ABSTRACT FROM AUTHOR]

Experimental research on 10 angle reinforced concrete (ARC) stub columns with a height to width ratio of 3.0 subjected to axial compressive load was carried out. The failure process of the specimen was observed and the load-axial displacement curves of the specimens were obtained. According to the experimental results, the influences of section size of specimens, battens spacing and concrete strength on the bearing capacity of the ARC stub columns were analyzed. The experimental process was simulated by finite element software ANSYS. The results show that the convex bulging deformation occurs in angle and batten of specimens near the middle position of columns when the specimens fail. With the increase of the distance between the battens, the bearing capacity of specimens becomes smaller and the load-displacement curve decreases more obviously. So battens spacing is the important factor influencing the bearing capacity of the ARC stub columns under the same condition. Based on the experimental data and simulation analysis, a simple calculation formula for the bearing capacity of the ARC stub columns under axial compression is proposed. [ABSTRACT FROM AUTHOR]

The full-scale fire tests of three RC columns under axial load were carried out with standard heating curves. The immediate reactions and collapse states of tested columns were analyzed and the temperature distribution of sections and axial deformations were measured. The degradation of bearing capacity of RC columns was found mainly on the following respects : the degradation of concrete strength, the increase of axial deformations and the destructions of working performances. Computer simulation compiled by author was done using the finite element method. The numerical results agree well with test data. A simplified calculation formula is put forward for RC column bearing capacity under fire, which is proved to be reliable according to the comparisons between test record and calculation results. [ABSTRACT FROM AUTHOR]

Based on the continuous reinforced concrete slab in shear-wall structure, tests of twelve one-way slab specimens restrained by shear-walls were carried Out to investigate the slabs' bearing performance under lateral restraint condition. Testing results show that, influenced by compressive membrane action, average ultimate load capacity of specimens is 138. 3% of the calculation results using upper-bound method when the ratio between the lateral restraint stiffness and specimens' own stiffness is 0. 022 : 1. The influence of stiffness ratio between support and central slab, vertical load on ending wall, span-height ratio of central slab, steel ratio and lateral restraint force on specimens' bearing performance is also investigated. The relationship between central deflection and the critical point of compressive membrane action and tensile membrane action is given by the test. [ABSTRACT FROM AUTHOR]