Vacuum preloading film pressing groove extension construction method

The invention provides a vacuum preloading film pressing groove extension construction method which includes the steps of film pressing groove extension and sealing film laying. In the film pressing groove extension step, an original film pressing groove which can not be dug to an airtight layer is horizontally moved to the outer side of a region, and digging is performed after the position of the film pressing groove is determined again so as to guarantee that a sealing film can be pressed in a film pressing groove airtight soil layer after film pressing groove extension. In the sealing film laying step, after film pressing groove extension, the size of the sealing film is adjusted according to actual extension size, the sealing film is laid, and a vacuum preloading construction stage starts after sealing film laying. The vacuum preloading film pressing groove extension construction method is convenient to use, it can be ensured that digging can be performed to the airtight layer, the sealing effect is guaranteed, and the preloading effect of a whole vacuum preloading area is guaranteed.