Multi-layer reinforced concrete frame bridge for co-construction of mountain urban traffic and square and construction method of multi-layer reinforced concrete frame bridge

The invention discloses a multi-layer reinforced concrete frame bridge for mountain urban traffic and square co-construction and a construction method of the multi-layer reinforced concrete frame bridge. The frame bridge comprises a plurality of supporting pile systems (1), a plurality of supporting structures (2) capable of adapting to space deformation, a plurality of top-layer assembly type steel-concrete composite beams (3), a plurality of middle-layer assembly type steel-concrete composite beams (4), a plurality of steel pipe frame columns (5), a plurality of beam-column joint areas (6), a plurality of reinforced concrete cast-in-place piles (7) and a plurality of anti-falling beams (8). The construction method comprises the steps that the top-layer longitudinal distribution steel beams (34) and the middle-layer top-layer longitudinal distribution steel beams (44) are hoisted, positioned and installed on site in a layered mode, and the top-layer cast-in-place reinforced concrete panels (33) and the middl