Assembly type composite wallboard bottom horizontal joint connecting method

The invention belongs to the technical field of buildings and discloses an assembly type composite wallboard bottom horizontal joint connecting method. The assembly type composite wallboard bottom horizontal joint connecting method includes the following steps that firstly, bin separating sealing bars are stuck to a structure floor plate, the bottom of a composite wallboard is isolated and dividedinto multiple grouting bin sections, the length of the grouting bin sections is smaller than 1 m, and the part, corresponding to each grouting bin section, of the bottom of the composite wallboard isprovided with an embedded grouting pipe and an exhaust hole; secondly, ash cakes are laid on the structure floor plate below the composite wallboard, and then lifting of the composite wallboard is conducted; thirdly, a wall side horizontal joint on the indoor side of the bottom of the composite wallboard is blocked through a foam bar, a wall side horizontal joint of the outdoor side is blocked through a foam bar or an axi