Detachable double-layer nonlinear vibration reduction fastener and assembling method thereof

The invention relates to the field of track line vibration reduction, in particular to a detachable double-layer nonlinear vibration reduction fastener which comprises an upper iron base plate, a lower iron base plate and a rubber base plate, and the upper iron base plate, the lower iron base plate and the rubber base plate are each of an overall symmetrical structure. Connecting bosses are symmetrically arranged on the two sides of the lower iron cushion plate, a first connecting through hole and a second connecting through hole are formed in the two sides of the upper iron cushion plate and the two sides of the rubber cushion plate in a matched mode, and the connecting bosses are arranged in the first connecting through hole and the second connecting through hole in a penetrating mode. A connecting sleeve arranged on the connecting boss in a sleeving mode is arranged on the upper iron base plate, a locking assembly is arranged on the inner wall of the connecting sleeve and the outer wall of the connecting b