Jack unloading supporting device for supporting beam and pulling column

The jack unloading supporting device comprises a bottom plate, a first stand column, a second stand column, a supporting table, a joist, a first guide column, a supporting plate, a jack, a second guide column and a plurality of unloading gaskets. The lower ends of the first upright and the second upright are fixed on the upper end surface of the bottom plate; the lower end of the supporting table is fixed to the upper end face of the bottom plate. The lower end of the first guide column is fixed to the upper end face of the first stand column. The lower end of the second guide column is fixed to the upper end face of the second stand column. Through holes are formed in the two ends of the joist respectively. The lower end of the jack abuts against the supporting table, and the upper end of the jack abuts against the lower end face of the joist. After the jack lifts the joist, the unloading gaskets are inserted between the first stand column and the second stand column of the joist. The upper end of the jack i