The work is devoted to the improvement of methods and models for design ensuring of strength of thin-walled engineering structures under the action ofoperational loadings complex. Justification for rational parameters and design solutions for thin-walled engineering structures is carried out according to thecriteria of mass minimizing, stresses reducing, and service life increasing. Various additional criteria such as cost, manufacturability, economy, energyefficiency, can be taken into account in the formation of the quality function. The dependences approximations of criterion values, which are graduallylocalized, from variable parameters are taken into account. The structure, design and technological solutions of thin-walled engineering structures, structural parameters and operating modes are the generalized parameters. This provides a solution to the problems of a single analysis, multivariate studies, as well as the justification for rational design and technological solutions. The following generalizations are considered: unification, expediency, efficiency, loading identification, forecasting, tune-up in development of known approach. The algorithmization of proposed methods for calculating of the stress-strain state of thin-walled engineering structures has also been carried out based on a combination of the advantages of universal and special systems. A number of applied problems are solved. Parametric finite element models of researched objects are developed based on a set of studies of the stress-strain state of the power elements. The rational design parameters of innovative thin-walled engineering structures are determined. The results of experimental studies of innovative tank cars, platform cars and loading cranes, which are designed and manufactured based on the implementation of recommendations from research, are presented. Comparative experimental and computational studies of the structures stress-strain state were carried out. They are combined with certification tests with stresses evaluation in power elements. During the tests, regularities were established that determine the dependence of the loadings components onthe structure from various factors. Numerical models parameters verification of thin-walled engineering constructions elements was carried out. Designed onthe basis of researches innovative structures have improved technical and economic characteristics compared with similar ones.