Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determin...Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determine these interactions, which can have a great number of combinations, the use of a computational model is of vital importance, in this case, the program FERROVIA 1.0 (RAILROAD 1.0) was used. A critical study developed the program FERROVIA 1.0, and its variables were characterized based on values observed in the literature. After initial characterization was carried out, a comparative study was performed on the sensitivity between these variables and the indications of significant behavior for a railway deformed by the known load of a wheel. A statistical program was used to correlate the elements. The intention was to launch the program FERROVIA 1.0 and later use it for 2,187 combinations. The data used in these correlations corresponded to the normal values for the elements used in railroad engineering practice. Our main goal is to understand the behavior of the track vertical deflection according to the variation of the scaling of the various elements of the railway,展开更多
We constructed a single C-Bezier curve with a shape parameter for G^2 joining two circular arcs. It was shown that an S-shaped transition curve, which is able to manage a broader scope about two circle radii than the ...We constructed a single C-Bezier curve with a shape parameter for G^2 joining two circular arcs. It was shown that an S-shaped transition curve, which is able to manage a broader scope about two circle radii than the Bezier curves, has no curvature extrema, while a C-shaped transition curve has a single curvature extremum. Regarding the two kinds of curves, specific algorithms were presented in detail, strict mathematical proofs were given, and the effectiveness of the method was shown by examples This method has the following three advantages: (1) the pattern is unified; (2) the parameter able to adjust the shape of the transition curve is available; (3) the transition curve is only a single segment, and the algorithm can be formulated as a low order equation to be solved for its positive root. These advantages make the method simple and easy to implement.展开更多
文摘Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determine these interactions, which can have a great number of combinations, the use of a computational model is of vital importance, in this case, the program FERROVIA 1.0 (RAILROAD 1.0) was used. A critical study developed the program FERROVIA 1.0, and its variables were characterized based on values observed in the literature. After initial characterization was carried out, a comparative study was performed on the sensitivity between these variables and the indications of significant behavior for a railway deformed by the known load of a wheel. A statistical program was used to correlate the elements. The intention was to launch the program FERROVIA 1.0 and later use it for 2,187 combinations. The data used in these correlations corresponded to the normal values for the elements used in railroad engineering practice. Our main goal is to understand the behavior of the track vertical deflection according to the variation of the scaling of the various elements of the railway,
基金supported by the National Natural Science Foundation ofChina (No. 60673031)the National Basic Research Program(973) of China (No. 2004CB719400)
文摘We constructed a single C-Bezier curve with a shape parameter for G^2 joining two circular arcs. It was shown that an S-shaped transition curve, which is able to manage a broader scope about two circle radii than the Bezier curves, has no curvature extrema, while a C-shaped transition curve has a single curvature extremum. Regarding the two kinds of curves, specific algorithms were presented in detail, strict mathematical proofs were given, and the effectiveness of the method was shown by examples This method has the following three advantages: (1) the pattern is unified; (2) the parameter able to adjust the shape of the transition curve is available; (3) the transition curve is only a single segment, and the algorithm can be formulated as a low order equation to be solved for its positive root. These advantages make the method simple and easy to implement.