Flexible sling hoisting device and method for bridge construction

The invention relates to the technical field of bridge construction, in particular to a flexible sling hoisting device for bridge construction, the device comprises two groups of hoisting seat assemblies, two groups of clamping assemblies, two groups of telescopic assemblies, two groups of position adjusting assemblies and two groups of collecting assemblies, each group of clamping assemblies is in one-to-one correspondence with each group of hoisting seat assemblies, and each group of telescopic assemblies is in one-to-one correspondence with each group of clamping assemblies. The lower ends of the two lifting seat assemblies are connected with outwards-extending flanges at the two ends of a box girder respectively, the upper surfaces of the lifting seat assemblies are fixedly connected with the lower portions of the clamping assemblies, and the middles of the lifting belts penetrate through the upper portions of the lifting seat assemblies and the middles of the clamping assemblies respectively and then are