Since past masonry structures were built by time-honored method of trial and error. Structural weakness or overloading, dynamic vibrations, settlement, as well in-plane and out-of-plane deformations can cause failure of masonry structures. To prevent the accidental situation in heritage buildings, safety criteria specified by determining deformation limit between interacting parts of masonry arch shell. At the same time cracked masonry shell part interaction also must be specified by friction because safe exploitation of building after crack forming is possible. The foundation settlement effect is the reason of shell part disintegration and hinge forming in the heritage’s vaulted structure. After support deformations and crack forming in shell, structures thrust line change position in cross section and internal forces relocates significantly. Simulation of hinge mechanism between rotating masonry parts is performed in the present investigation. Reverse engineering principles used in manufacturing processes adopted for structural analyze. The deformed state model of Riga Dome Cathedral’s vaulted shell has been created using laser scanner surface scanning. Dissertation consists of sequently joined methodes for deformed heritage masonry vaulted structure analysis. The proposed methods are: a) three-dimensional scanning of heritage structure by means of 3D laser scanners to measure vaulted structure surface and further convertation into surface mesh model; b) digitalized surface model preparing and transfer to structural computational programs; c) selection of masonry material investigation methods to describe the heritage masonry structure material physical and mechanical properties; d) test result processing and material property definition for structural analyze; e) heritage structure deformed stage analyze and result validation with crack monitoring data; f) safe criteria development according to structure support unequal settlement. The presented set of methods provides vaulted structure analysis in deformed stage to define safe exploitation limits and plan the reinforcement or reconstruction of the analyzed structure. Presented methodologies includes the less time-consuming vault geometry measuring method, model preparation method adopted by „reverse engineering” for mechanical engineering and deformed stage computational analyze using popular structural analyze program. Crack monitoring system of Riga Dome Cathedral’s vaulted shell is managed for three years to establish correlation between support settlement, temperature loading and crack movement. Deformed state model and long term crack monitoring is used for analysis of influence the support deformations. Deformation criteria are developed for safety exploitation of heritage masonry structures. The paper includes 70 pictures, 6 tables, and provides references to 153 literature sources.