BRIDGE DESIGN METHOD

摘要

PROBLEM TO BE SOLVED: To provide a bridge design method that can ensure wind resistance stability of a bridge while accomplishing cost reduction.;SOLUTION: The present invention is a design method for a multispan bridge with a superstructure in which a length ratio B/D of cross-sectional sides of an envelope quadrangle varies along the bridge axial direction where B and D are, respectively, width and height of an envelope quadrangle that envelopes a cross-sectional outer profile of the superstructure, which is approximately orthogonal to the bridge axis direction of the bridge. In the design method for a multispan bridge, values of an equation (1) shall always be 0 or more: where C_L is a lift force factor of the superstructure, α is an angle which an average direction of the wind blowing on the superstructure forms with the horizontal direction (positive in the blow-up direction), dC_L/dα is a gradient of the lift force factor, and further L_n is the n-th span length in the superstructure counted from the end of the superstructure, S_n is the n-th gradient of the lift force factor, and A_n is the degree of the maximum deflection vibration mode in the span.;COPYRIGHT: (C)2012,JPO&INPIT