The thickness of stilling basin bottom plate can be calculated according to the requirements of anti scour and anti floating, and the large value of two calculation results can be taken. However, the initial end of the stilling basin of the sluice is provided with a reverse filter, so it is not necessary to carry out the anti floating checking calculation, so only the thickness of the stilling basin bottom plate needs to be calculated according to the anti scour requirements.According to the anti scour requirements, the thickness of the beginning end of the stilling basin bottom plate is calculated according to the following formula