Bottom-to-shell joint is one of the most critical areas in vertical cylindrical storage tanks, both in terms of the number of detected flaws and the causes of failures. The primary factors contributing to the present state include the structural peculiarities of the shell-to-bottom joint, leading to incomplete fusion in the middle between the double filletgroove welds (double fillet welds) and, consequently, low inspectability. This results in a complex stress-strain state with maximum stress levels in the area of the shell-to-bottom joint. Thus, improving the existing design of the bottom-to-shell joint is relevant.This article presents the results of comparative resource evaluation tests conducted on the typical design of the shell-to-bottom joint and two prospective designs: one with complete penetration weld and another with a T-section. The tests were conducted using prototypes that replicate the necessary structural properties of the shell-to-bottom joint and the stress distribution diagram, allowing testing on standard servo-hydraulic machines. The results obtained indicate that all considered designs of shell-to-bottom joints, when free from flaws, exhibit high reliability, ensuring safe operation even under double the operational stresses for a minimum of 50 years. Considering the improved inspectability and feasibility of manufacturing these prospective shell-to-bottom joint designs, along with their comparable production costs, they can be recommended for practical applications.