The question of the use of qualification tests of adhesive systems to determine their residual life is considered. The purpose of the study. Testing the hypothesis about the possibility of applying qualification tests of adhesive systems and regression equations to predict the residual life. Methods. Experimental studies of water resistance of adhesive joints, tensile strength along fibers, heat and frost resistance of adhesive joints, and resistance of adhesive joints to delamination were carried out. Results. Based on the test results, data were obtained on the water resistance of adhesive joints, the tensile strength along fibers, the heat and frost resistance of adhesive joints and the resistance of adhesive joints to delamination. The dependences of the limit on the strength of time are obtained. The residual life was calculated using the obtained equations. Discussion. Based on the studies, it was found that the qualification test data of adhesive systems can be used to determine their durability (residual life). In the future, the results of these studies can be applied for widespread implementation and for inclusion in regulatory documents.

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Test methods for reinforcing steel is not suitable for fiber reinforced polymer (FRP) rebars because it can cause destruction of the edge zones of the samples. The polymer matrix and fibers are not able to resist compression across the fibers. Existing test methods for FRP rebars do not contain information about the equipment and composition of the adhesive composition. The purpose of the study is to clarify the adhesive composition and design of the FRP specimen anchor. Methods. There were experimental studies of fiberglass reinforcement polymer rebars samples carried out. The following factors varied: the proportion of the components of the adhesive composition; the area of the adhesive contact of the FRP specimen anchor. Results and Discussion. The proportion of epoxy glue and quartz sand providing the test of automatic transmission is determined. The influence of the thread on the inner surface of the FRP specimen anchor on the adhesive strength in the contact zone «adhesive composition-steel» is estimated. A universal three-dimensional model of the centering plug for manufacturing using additive technologies has been developed. Conclusions. The results of the investigation can be used to upgrade the FRP rebars test methods.

Introduction: The paper addresses the issue of using regression equations to determine the residual operating life of structures made of wood of various species in high humidity conditions. Purpose of the study: The study is aimed at deriving general equations for calculation of the ultimate life of wooden structures using univariate regression equations for subsequent calculation of the residual operating life (option 1), or equations for immediate calculation of the residual operating life (option 2). Methods: Univariate regression equations are used: linear, logarithmic, seconddegree polynomial, power, exponential, natural exponential, and hyperbolic. Results: The authors derive general equations for calculation of the ultimate life of wooden structures for subsequent calculation of the residual operating life (option 1), and equations for immediate calculation of the residual operating life (option 2), presenting advantages and disadvantages of both options. They propose an algorithm to process the obtained results in case the calculation is carried out using several equations at once. The authors also present an example of calculating the residual operating life using the second option. Discussion: Based on the proposed relationships, it is possible to determine the residual operating life of any wooden structures under any operating conditions.

Оценка остаточного ресурса объектов деревянного домостроения, в том числе исторических, может быть затруднена плохим состоянием рабочей, исполнительной, эксплуатационной документации. Традиционные методы расчета остаточного ресурса зданий и сооружений с учетом этого могут быть трудно реализуемы. В данной работе предлагается алгоритм оценки остаточного ресурса объектов деревянного домостроения с применением технологии информационного моделирования. Алгоритм основан на применении эксплуатационных информационных моделей и результатов обследования конструкций объектов капитального строительства. Приведены способы автоматизации расчета остаточного ресурса объектов деревянного домостроения при применении указанного алгоритма.