Institute of Machines Science

The study results of the additive construction production technology (3D concrete construction printing) economic efficiency in comparison with traditional construction methods in low-rise individual housing construction (IHC) segment are presented. The research relevance is due to the need for an objective assessment of the innovative technology competitiveness amid systemic challenges in the industry – staff shortages and stagnation in labor productivity. Based on the questionnaire method and open source data, a unique sample of implemented pilot 3D printing projects from key participants in the Russian market was formed and analyzed. A comparative analysis with an extensive database of standard projects built according to the traditional technologies was performed. The article identifies and substantiates the current objective price range for additive construction facilities, identifies key factors affecting their cost, and ranks the technology relative to traditional analogues. It is established that in terms of unit cost, 3D printing in construction is already competing with the top quartile of projects implemented according to traditional technologies. The results obtained form an empirical basis for assessing investment attractiveness and scaling potential of additive technologies in the construction industry.

The electroplastic effect in aluminum and its alloys is reviewed. The electroplastic effect is a phenomenon of a decrease in the strain resistance of a metal and an increase in its ductility under the action of a high-density electric current. The main methods of electroplastic processing are described, including the use of pulsed currents and external heating. The factors governing the kinetics of electroplastic strain and various physical effects influencing this process are discussed. The results of the molecular dynamics modeling and fractographic analysis are considered, which confirm the important role of the stress-induced grain growth in plastic straining of nanocrystalline metals and alloys.

Challenges in the robotization of monitoring and cleaning hard-to-reach areas in the annular space of pipe-in-pipe (PIP) heat exchangers, between a submersible borehole pump and the casing and between the containment shell and the installed stay cable in the course of the construction of cable-stayed bridges are considered. A new concept for a universal adaptive robot with a parallel structure capable of operating over a wide range of annular space gaps is presented. The advantages of this robot compared to the existing systems are demonstrated.

Monitoring the accuracy and performance of laser rangefinders without the use of extended testing grounds or reflective targets is an urgent metrology challenge. We examine the methods and devices for testing laser rangefinders not involving testing grounds, which include optical range simulators, fiber-optic delay lines, and electronic simulators. Their advantages, limitations, and applications are discussed. A matrix of possible technical solutions is constructed and analyzed. The research conducted allowed us to evaluate state-of-the-art methods and devices for testing laser rangefinders which eliminated the need for extended testing grounds with reflective targets.

The purpose of this study is to develop and describe software for the organization of labor protection during the construction of the Amur Gas Processing Plant (AGPP). The described methodology is based on risk assessment and selection of measures for managing the organization of construction and installation works. The professional risk management system was developed and put into practice in the 4th quarter of 2020. In 2022, based on the established database of identified hazards and their management measures, work was carried out to automate the process of hazard identification, as well as the formation of risk management maps and the familiarization of employees with the contents of these maps. The development and implementation of the proposed methodology has led to a significant reduction in the rates of health disorders of AGPZ employees both in terms of work-related diseases and injuries. The software developed as a result of the conducted research for professional risk assessment and management is recommended for practical use in the construction of new petrochemical and gas chemical plants.

This paper considers compressive thermomechanical loading and its effect on high-temperature strength characteristics of single-crystal SLZhS5-VI high-temperature nickel alloy. This treatment has been shown to considerably improve ductility (relative elongation and relative contraction) of the alloy at room and elevated temperatures and increase its time to rupture and creep resistance at a temperature of 900°C owing to the decrease in the density of casting defects (micropores and microcracks) as a result of the lower strain rate.

One of the peculiarities of bending tests of polymer fibrous composites is the need to use cylindrical supports of significant radius to avoid indentation and “nipping” of a sample with low transverse strength. In the refined formulation, a number of effects of the use of cylindrical supports are considered, the influence of which is strictly estimated by expansions in small parameters. The limits of deflection, sample sizes, and support radii are established, when, with a given accuracy, the specified effects can be neglected when determining Young’s modulus and the ultimate strength for normal and shear stresses. It is shown that when finding the interlayer shear modulus, the error that occurs when sample rolls off the supports can be significant; therefore, for the described method, the radius of the supports must be taken into account.

Experimental studies of oscillations of the 18-m three-section concrete placing boom of an SB-126 truck-mounted concrete pump are performed. The test program included determination and analysis of boom oscillations in the vertical and horizontal planes, as well as its compression and torsion. The frequencies and forms of oscillations of the placing boom, dynamic loads in the boom metal structures, concrete pipeline and boom mounting bracket, and pressure in the hydraulic system of the central piston group and concrete mix in the concrete pipeline are determined.

At present, one of the pressing issues in mechanical engineering is the automation of production processes. Automation helps partially address the problem of personnel shortages and increase labor productivity. High-speed cyclic and positional manipulators developed at the Blagonravov Institute of Mechanical Engineering of the Russian Academy of Sciences (IMASH RAN), based on the use of high-coercivity permanent magnets, are presented. These developments can serve as a basis for creating manipulators with low and ultra-low lifting capacities for use in various industries.