The four-ground screw tower footplate is widely used in overhead transmission line angle towers

and it is important to accurately assess its safety level. In view of this

a tensile reliability analysis method based on the sample moment method is constructed in this paper. By establishing a refined numerical model of the four ground snail

the weak components and damage modes are analyzed; the limit state equation for the tensile damage of the four ground snail tower footplate is given based on the yield line theory

and finally the tensile reliability index of the four ground snail tower footplate is calculated by considering the randomness of materials and loads in a typical project with the sample moment method. The analysis results show that: the tensile reliability index of the four ground snail tower footplate is 4.220 9

which can well meet the requirements of the primary target reliability index; meanwhile

the thickness of the base plate has a significant influence on the tensile reliability index of the four ground snail tower footplate

and the reliability index can be increased by 10.11% after increasing the thickness by 8mm.