Large-scale-distance extensometer and accurate measurement system for cable force coefficient of suspension cable of suspension bridge

The utility model discloses a large-scale-distance extensometer and a system for accurately measuring the cable force coefficient of a suspension bridge sling, and belongs to the field of sling force measurement. The large-scale-distance extensometer comprises an extensometer body and an extensometer fixing device, the extensometer fixing device comprises a first hoop unit and a second hoop unit which are connected with the two ends of the extensometer body respectively, each hoop unit comprises a hoop anchor plate, hoop angle steel, a hoop straight anchor plate and a hoop arc-shaped anchor plate, one side edge of the hoop angle steel is welded to the hoop straight anchor plate, and the other side edge of the hoop angle steel is welded to the hoop arc-shaped anchor plate. The end portion of the extensometer body is fixed between the hoop anchor plate and the hoop angle steel through at least two bolts, and the sling is fixed between the hoop arc anchor plate and the hoop straight anchor plate through at least