Combined jacking iron of rectangular jacking pipe

The invention discloses a combined jacking iron of a rectangular jacking pipe, which comprises four trapezoidal basic jacking iron blocks, every two adjacent basic jacking iron blocks are detachably connected through a corner connecting block, a quick release device is arranged in a cavity in the middle of each basic jacking iron block, and each quick release device is connected with the corresponding corner connecting block. A plurality of connecting rods are symmetrically arranged at the two ends of the quick release device, the connecting rods are slidably arranged in the cavity of the foundation iron jacking block, one end of each connecting rod is connected with the quick release device, and the other end of each connecting rod extends out of the end slope of the foundation iron jacking block; and a plurality of connecting grooves for inserting the connecting rods are formed in the corner connecting blocks. The combined jacking iron for pipe jacking is controllable in overall quality, convenient to assem