Joining method for rigid suspension cable stiffening chord in incremental launching method construction

The invention discloses a joining method for a rigid suspension cable stiffening chord in incremental launching method construction. After a steel truss girder bridge is put in place through incremental launching, a gantry crane and deck truck cranes cooperate to hoist an auxiliary support, an upper-half chord member of the stiffening chord, a stand column and a lower-half chord member of the stiffening chord in sequence, and a joint is reserved in the middle of the stiffening chord; the jacking position and the jacking height and jacking force of each point are determined according to a finite element model calculation result in combination with an actual joint measured value; multipoint jacking of the whole bridge is carried out, staged loading is carried out according to the actual engineering condition, real-time monitoring is carried out, and preliminary butt joining of an upper joint body and a lower joint body is achieved; precise butt joining of the upper joint body and the lower joint body is completed through a screw joining device and a jack assembly correcting device. Precise joining of the rigid suspension cable stiffening chord in incremental launching method construction of a large-span steel truss girder is achieved through the staged loading and multipoint jacking method, the stability of the geometric dimension of a brigade structure is ensured, operability is high, construction is convenient, safety and stability are achieved, and the joining method is economical and reasonable and has promotional value in construction of the large-span steel truss girder bridge with the stiffening chord.