Construction method for filling concrete in steel tube arch bridge tube

The invention relates to a concrete filling construction method for a main chord pipe of a steel pipe arch rib of a concrete-filled steel pipe arch bridge when the span is large, the height is large and the pipe diameter is large. The method comprises the steps of cleaning a steel pipe, designing a mix proportion, symmetrically arranging a grouting hole, a temporary slurry discharging hole and an exhaust hole, symmetrically arranging a feeding pipe, a slurry discharging pipe, an exhaust pipe and a stop valve, symmetrically arranging a conveying pipe and a check valve, planning a pumping sequence, pumping concrete and the like. The concrete in the steel tube arch bridge tube shows plug flow movement rule, the concrete at the surrounding part has small disturbance, the setting time is earlier than that of the concrete in the central part, the friction resistance between the concrete in the central part and the concrete in the surrounding part is gradually increased along with the pumping and jacking of the conc