Drainage consolidation method for complex stratum of backfilling construction area above urban subway tunnel

The invention relates to a drainage consolidation method for a complex stratum of a backfilling construction area above an urban subway tunnel. A plurality of high-pressure jet grouting piles arranged in a quincunx shape are formed in a reinforcing stratum above the subway tunnel through rotary jet grouting, then manufactured perforated steel pipe sets are immediately and directly inserted into the centers of the high-pressure jet grouting piles, after the perforated steel pipe sets are inserted, a temporary seal of a common perforated steel pipe at the uppermost end is removed, double grout is injected into the perforated steel pipe sets, and finally a plurality of precipitation wells located on the two sides of the reinforcing stratum are dug in a well digging stratum. According to the drainage consolidation method, the complex stratum of the backfilling construction area can be reinforced. 本发明涉及种用于城市地铁隧道上方回填造地区复杂地层的排水固结法，在地铁隧道上方的加固地层中通过旋喷注浆形成若干个梅花型布置的高压旋喷桩柱，之后立即向高压旋喷桩柱的中心处径直插入制成的钢花管组，插入钢花管组后，去除最上端的普通钢花管的临时