The article presents the results of analysis of the stress-strain state of a five-span composite structure of a road bridge, made on a beam unbroken circuit. The calculation is performed in the LIRA program complex under the elastic work of materials on the action of shearing and tearing forces. The main purpose of the work was to determine the coefficient of stress concentration coefficient (SCC) in the zone of rigid anchors for concrete slabs of the roadway. For this purpose, a section of a plate with a metal beam and unifying elements was modeled, broken down into small volumetric and lamellar bodies. This allowed us to analyze in detail the nature of the distribution of normal stresses along the height and length of the span structure. The obtained coefficient can be used when calculating the existing designs for endurance and strength, and also when determining the residual life of bridge structures to predict their service life. © Published under licence by IOP Publishing Ltd.