Jack symmetric precompaction construction method for hanging basket girders for bridge hanging basket suspension casting construction

The invention relates to a jack symmetric precompaction construction method for hanging basket girders for bridge hanging basket suspension casting construction. The method comprises the following ten steps: 1, selecting a precompaction field; 2, assembling the hanging basket girders; 3, symmetrically putting the two hanging basket girders on four wood pads; 4, prefixing rear anchor points; 5, assembling a middle fulcrum point block; 6, mounting a hanging basket loading system; 7, measuring the relative position size of the two hanging basket girders before loading; 8, loading and measuring the relative position size of the two hanging basket girders; 9, unloading and measuring the relative position size of the two hanging basket girders; and 10, calculating and analyzing according to measurement data. The method has the advantages that the precompaction on bridge can be substituted, thus heavy workload for suspending sandbags can be avoided; the precompaction work efficiency is effectively quickened so as to save massive precompaction construction time; load can be applied by the jack, and precompaction data can be accurately controlled; and the precompaction process and observation process of the hanging basket are performed in the field with high safety and strong controllability.