A 2D experiment is carried out in the wave flume to research the relationship between the three major physical parameters and their main affecting factors when the regular wave impulses the perforated caissons with the upper structure. In this paper, the three major physical parameters are the total horizontal wave forces, the total vertical wave forces and the phase shift between the horizontal and vertical force acting on the perforated caissons with the upper structure, respectively. According to the experimental data, the method of correlation analysis is used to study the relationship between three major factors and their main influencing parameters such as the relative height of the upper structure, the relative water depth, the relative width of chamber and wave steepness, respectively. Then the correlation equations to calculate the three major physical parameters are obtained from the Least Square Method. It is compared that the total horizontal moment on perforated caissons between calculated values and measured data, here the calculated moment values are obtained from the proposed equation for the calculation of wave force on the perforated caissons, the method mentioned in Ref.  to calculate the wave forces on the perforated caissons without top cover and the method adopted in "The Design Code of Marine Hydrology" to compute wave forces on the solid caissons.
Breakwater or quay is often used to load and unload cargoes, to take boat or debark and so on. Therefore, the constructions such as perforated caissons are built in the upper structures. When the height of the upper structures from the still water level is low, the wave movement characteristic in the chamber of perforated caissons is affected by the upper structures. It is necessary to discuss the wave forces acting on the porous caissons with the upper structures.