Abstract: A method for inversion of a path mileage and offset by using a known coordinate point, comprising: based on coordinates of a known point P and curve elements of a start location and an end location of a curve element, first segmenting or not segmenting the curve element according to a corner of the curve element to obtain a plurality of curve sub-elements (AiBi), and calculating curve elements of the curve sub-elements (AiBi); taking any curve sub-element (AiBi) to calculate a half chord length S and a straight corner ?, and performing precision determination and convergence correction according to S and ?, the point P being always effective with respect to the curve sub-element (AiBi) in the correction process; and performing cyclic convergence calculation to finally obtain a distance from the point P to any point on a chord line or an arc line as an offset of the curve sub-element (AiBi) corresponding to the point P and to obtain a mileage of the curve sub-element (AiBi) corresponding to the point P.

Abstract: A construction method for the upright lifting of a large-tonnage box girder to a bridge, and an erection method for the large-tonnage box girder. The construction method comprises: constructing a lifting station (2) at reserved bridge piers (1); disposing a girder lifting base (3), lifter traveling rails (4), and a mounting lifter (6) in the lifting station (2); directly erecting a box girder (7) by the lifter (6) in a way that the lifter (6) travels to a position above the base (3) and erects the box girder (7).