Expansion bolt

The utility model discloses an expansion bolt which comprises a screw rod, a conical nut, a threaded conical nut, a first expansion pipe, a second expansion pipe, a gasket and a nut. Threads, namely an upper thread and a lower thread, are arranged at two ends of the screw rod; the conical nut is fixed on the screw rod and is positioned between the upper thread and the lower thread; the expansion pipe I is sleeved outside the screw rod and is positioned above the conical nut; the expansion pipe II is sleeved outside the screw rod and is positioned below the conical nut; the conical nut with threads is arranged at the top of the screw rod; the nut is arranged at the bottom of the screw; a gasket is arranged between the nut and the second expansion pipe; longitudinal strip-shaped notches areformed in the upper portion of the first expansion pipe and the upper portion of the second expansion pipe respectively, and the conical nut with the threads can be embedded into the first expansion pipe and the second expans