ROUND TYPE CHANGING SECTION STEEL GIRDER, STEEL GIRDER BRIDGE WITH ROUND TYPE CHANGING SECTION AND MANUFACURING METHOD FOR THE STEEL GIRDER HAVING ROUND TYPE CHANGING SECTION

摘要

The present invention relates to a bridge having a circular-arc-shaped tapered steel girder, and a method for manufacturing a circular-arc-shaped tapered steel girder. The bridge having a circular-arc-shaped tapered steel girder includes an upper plate of the bridge; and a steel girder installed at a lower part of the upper plate to support the upper plate, wherein the steel girder is integrally connected to both width-directional ends of the bridge, has a circular-arc-shaped cross section calculated by the following equation (W = 2rsin/2, h = r - rcos/2 = r(1-cos/2), where W is a bridge width, h is a girder depth at any point, is a virtual angle of a circular arc connecting both ends of the bridge, and r is a virtual radius of the circular arc), has a girder depth continuously changing along the longitudinal direction of the bridge, has a trapezoidal shape having a distance between each point of the fixed point as a length and a girder depth at each point as a width to bend the steel plate into a circular arc shape so as to be integrally formed without joints in the width direction of the bridge, and has a tapered girder having a cross section in which a girder depth is continuously changed.