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The paper presents a computer modelling technique for modernization of bridgework operations by building-up a mounted reinforced concrete slab. It implements the technique of the evolutionary transformation of a model in one calculation cycle with redistribution of forces between the elements of the built-up section, and consideration of the impact of elastoplastic and rheological properties of the materials. Consideration of the concrete creep implies the application of the generalized kinetic curve of prolonged deformation and phenomenological deformation development equations based on the colloid-chemical concept of the prolonged concrete deformation mechanism. The creep control was implemented through new structural coefficients which determined the structure of matrix interlayers between the sand grains, and mortar between the crushed stone grains. The technique proposed was realized in the program complex “LIRA-SAPR” based on the building information modelling (BIM) and the finite element method (FEM). The multistage modelling technique was shown by an example of calculation of a motorway bridge slab span within the transport structures under modernization along the Lev Landau Avenue in Kharkiv (Ukraine).

Relevance of the study: As the experience of advanced countries shows, the development of the economy in our country, in particular, in the transportation services market, is associated with the development of interaction between all types of transport. Thus, in modern conditions, for the growth of the role of railway transport, multimodal transportation, which is important for the interaction of Ukraine with the countries of Europe and the East, is becoming important and will also help minimize costs and preserve the environment. Therefore, the issues of evaluating the introduction of multimodal transportation with logistic principles are discussed in the article. It is shown how to determine the marginal substitution rate in the conveyance type while using various modes of transport, based on the utility function and transportation costs. Purpose of the study: The purpose of the article is to develop measures to improve the functioning of parts in multimodal freight delivery routes by minimizing transportation costs, taking into account quality indicators. For this purpose, the following tasks have been set and are being solved: to develop a model for evaluating the efficiency of using different modes of transport with optimal costs; to choose a method for estimating the optimal delivery route and freight volumes; to evaluate the efficiency of transportation technology based on a qualimetric indicator. Approaches: An approach to a comprehensive evaluation of the effect from the activities of transport enterprises in multimodal transportation based on cost optimization, with the qualimetric indicator, and aimed at maximizing the satisfaction of shippers' requirements is offered when determining the route of such transportation parameters as the cost and the quality of freight delivery. Results: The results of the theoretical generalization and analysis of approaches to the formalization of the functioning process in multimodal transportation systems for the delivery of goods by rail and road modes of transport are presented in the article. The significance of the results. The materials in the article are of practical value for employees of transport and logistics companies and enterprises, scientists, and pedagogical workers to improve their professional level. [ABSTRACT FROM AUTHOR]