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The article is devoted to the research of application of reinforcing steel of a new spiral profile for reinforcement of reinforced concrete constructions. The article presents the results of experimental studies of prism specimens with screw four-row reinforcement with diameters of 20 and 32 mm of class Av600P and concrete of classes B30 and B60 under static compression loading. The purpose of the research was to justify the introduction into practice of the construction of an innovative screw reinforcement profile, which will develop the ideas and principles that have become the basis for the widely used six-row A500SP profile, whose design solution (the absence of longitudinal ribs with the arrangement of transverse protrusions in four rows with the possible formation of a two-start screw thread by them) makes it possible to significantly increase the rejection minimum value of the Röhm criterion (fR ≥ 0.075), which characterizes and determines the strength and deformability of the adhesion of reinforcement to concrete, which determine the strength and crack resistance of reinforced concrete structures, and, consequently, their operational safety and reliability. The coupling joints of screw reinforcement can significantly speed up the process of reinforcing work at the construction site as a result of replacing labor-intensive and expensive welded joints. The results of the research showed the effectiveness of application of new screw reinforcement of the Av600P class for reinforcing compressed reinforced concrete elements made of concrete of classes B30÷B60 with coupling threaded contact, partially contact and non-contact butt joints of the reinforcement.

The authors present the results of RD on the topic of coupling slip of threadbar of class Av500P. The aim of the work was to obtain experimental data to study the effect of the threadbar coupling on the slip (deformability) of the joint and taking into account the characteristics of the joint in the design of structures. The strength and deformability of coupling samples of threadbar with a diameter of 16, 25 and 40 mm with an innovative four-sided (four-row) thread profile of class Av500P have been studied in accordance with the methodology of international and Russian standards. The samples were made with different tightening torques of the lock nuts and anchor-adhesive compositions inside the coupling. Along with the results of the study, it can be concluded that these couplings of innovative four-row threadbar of class Av500P meet the requirements of international and Russian standards when applying a certain tightening torque to the tightened lock nuts, depending on the diameter of the fittings to be joined and the use of anchor-adhesive compositions on large and medium diameters of the threadbar to be joined. The diagrams of thread joints obtained during the experiment can be used in design practice when design reinforced concrete structures according to the deformation model. Together, this makes it possible to introduce thread joints into the Russian construction regulatory code.

The main activities conducted at the department for technical diagnostics and repair technologies of the All-Russia Thermal Engineering Institute (JSC "VTI") are described. It is shown that the diagnostics of the main and auxiliary power equipment can be efficiently performed using specialized monitoring tools. Effective methods and tools for assembling rotor couplings of turbine units are presented. Technologies for repairing the blade apparatus of steam turbines arereviewed. [ABSTRACT FROM AUTHOR]

Mithilfe einer mehrmonatigen zerstörungsfreien Monitoringmaßnahme an zwei Rampenbauwerken der Köhlbrandbrücke, Hamburg, wurde die Ermüdungsbruchgefahr des Spannstahls an den Spannstahlkopplungen infolge Verkehr‐ und Temperaturbelastung bauwerksbezogen beurteilt und bewertet. Hierzu wurden im Zeitraum August 2013 bis August 2014 dynamische Rissbreitenmessungen am Überbauquerschnitt im Bereich der Koppelfugen sowie Temperaturmessungen zur Bestimmung der Temperaturverteilung über den Querschnitt durchgeführt. Ziel des Monitorings war es, den tatsächlichen Bauwerkszustand orts‐ und objektspezifisch zu erfassen. Im theoretischen Nachweiskonzept konservativ anzunehmende Parameter (z. B. örtliche Spannkraftverluste, Temperaturgradient) können so durch realistische Ansätze präzisiert werden. Im Rahmen dieses Beitrags werden das entwickelte Monitoringkonzept, die Messergebnisse und deren Implementierung in den rechnerischen Nachweis vorgestellt. Monitoring based proof of fatigue resistance of prestressing steel at coupling joints of the Köhlbrandbrücke With the help of a non‐destructive monitoring of two structures of the eastern ramp of the Köhlbrandbrücke, Hamburg, the danger of fatigue fracture of prestressing steel of coupling joints due to traffic and temperature loading has been assessed and evaluated. To this aim, dynamic measurements of the crack movements and of the temperature distribution over the cross section were carried out in the period August 2013 to August 2014. The aim of the monitoring was to detect the actual state of the structure and to specify in the theoretical verification concept conservatively assumed parameters (e.g. local stress losses, temperature gradient) by site and object specific approaches. Within the framework of this paper the developed monitoring concept, the measurement results and their implementation in the theoretic verification are introduced and discussed. [ABSTRACT FROM AUTHOR]

It is proposed that the flange joints for turbine rotors and for the horizontal feedthrough of the cylinder housings be assembled using a technology that avoids traditional impact tools, as well as heating of the studs. This technology involves the use of specialized equipment and a modified fastener design. The insertion (extraction) of the fastener is monitored both with a dial indicator and based on the jack force measured by the pressure from the hydraulic pump, which reduces the errors owing to human factors. [ABSTRACT FROM AUTHOR]