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Prestressed concrete continuous rigid frame bridge is a structural integrity, reasonable force, driving comfort, moderate cost, simple and beautiful shape bridge. Both large-span continuous beam and T-type rigid frame bridge deck expansion joints, no bearing, convenient construction, better seismic capacity. Because girders and piers consolidation, the pier at the top of the main beam has a larger negative moment, small positive moment at the cross beam, continuous rigid frame bridge than continuous beam bridge greater leap. But in the long-term design practice, continuous rigid frame bridge design parameters many space force characteristics, structural analysis is complex, so often by virtue of experience, design optimization, the lack of systematic and scientific optimization method. Orthogonal experiment as a scientific experimental design, the concept is clear, easy to operate; applied to continuous rigid frame bridge beam design parameter optimization, less the number of tests, test results, and is easy to come to a better design parameters. A continuous rigid frame bridge under construction highway, around the main beam design parameters optimization study, the main work is as follows: (1) at home and abroad prestressed continuous rigid frame bridge the development and research of the status quo continuous rigid frame bridge design parameters of a comprehensive analysis of side span ratio the BEAMS high-span ratio, the central beam high cross-ratio of four design parameters of the power of the beam bottom curve, suitable for positive deposit of the 4 levels of the test parameters. (2) Select the appropriate orthogonal design table, the use of space beam element 16 bridges finite element test model, on the basis of the analysis of the structure, strength, deflection, the amount of concrete and impact factor as an indicator of the main beam The four key parameters of a number of optimization to obtain the optimal combination of parameters and parameter applies to each index value. (3) follow the static test model, the continuous rigid frame bridge E1 earthquake, 3 Victoria vibration response spectrum analysis of the main beam design parameters for the end of the bridge pier, pier top section of the main beam, main beam cross- in cross-section, the control of three key nodes moment orthogonal test, the obtained bending moment value tends to reduce the optimal combination of parameters, as well as the values ??of various parameters. (4) optimization of static and dynamic optimization of the earthquake on the basis of the main beam, the same optimized design parameters difficult to bridge both static demand and power demand. Continuous rigid frame bridge the main beam design, the overall arrangement, or be focused response to continuous rigid frame bridge static and dynamic demand.
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