Construction method for main arch ring of vertical rotation stepping half-through tied arch bridge

The invention relates to a construction method for a main arch ring of a vertical rotation stepping half-through tied arch bridge, which comprises the following steps of: dividing the arch ring into two half spans, horizontally splicing the two half spans on approach bridges on two banks, dragging the arch ring to vertically rotate by adopting a vertical rotation buckling system, simultaneously pushing the arch ring to move towards the midspan by adopting a pushing system, repeatedly pushing and vertically rotating, and gradually moving the two half-span arch rings to the midspan to close. The pushing method and the vertical rotating method are organically combined, on one hand, the problem that an existing pushing method can only conduct whole-span pushing and is limited by the span is solved, on the other hand, the problem that an existing vertical rotating method cannot be used when an obstacle exists in the skewback position is solved, and pushing installation of the large-span main arch ring is successfu