Bi-Prestressing System Makes the Girder Depth Lower

Design and construction of Chuo-Koen foot-bridge

Abstract

This paper presents design and construction of the bi-prestressed foot-bridge whose depth-span ratio is 1/38. Bi-Prestressing System requires typical post-compressioning prestressing tendons arranged in the upper part of the girder that offset unfavorable axial compressive stresses due to conventional post-tensioning tendons located normally in the lower part of the girder. This system makes the depth of prestressed girder more reduced and gives the best choice when the space below the bridge is not enough.