METHOD FOR CONSTRUCTING MAIN TOWER OF DIAGONAL TENSIONING BRIDGE

摘要

PROBLEM TO BE SOLVED: To provide a method for constructing a main tower of a diagonal tensioning bridge, which reduces the weight of a steel shell portion of the main tower, prevents stress to concentrate on a lower bed portion of the steel shell portion in a concrete portion, and improves the workability when the main tower is constructed. ;SOLUTION: According to the method, a plurality of steel shell units 24 are stacked on a main tower construction portion of the diagonal tensioning bridge to set the steel shell portion 20, and then concrete is lined along the steel shell portion 20 such that a bridge-axially central portion thereof is left like a belt, to thereby form a pre-cast concrete portion 22A. Thereafter, a diagonal member 14 is anchored to each anchoring structure 18 of the steel shell portion 20 via an anchor 16, and tension T is introduced to each diagonal member 14. Lastly, concrete is placed on the bridge-axially central portion of the steel shell portion 20. In this manner, the pre-cast concrete portion 22A is not formed at the bridge-axially central portion of the steel shell portion 20, and therefore a horizontal component (tensile force) of a diagonal tensile force T is borne only by the steel shell portion 20, while a vertical component (compressive force) of the diagonal tensile force T is borne by a composite cross section between the steel shell portion 20 and the pre-cast concrete portion 22A. As a result, the burden on the steel shell portion 20 is reduced.;COPYRIGHT: (C)2003,JPO