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The article is a review of the monographic study “Law in the context of global climate change”, prepared by the author’s team under the scientific editorship of Professor V. V. Blazheev and Professor M. A. Egorova. In which the problems of legal regulation of environmental safety and environmental protection, the development of law and economics, constitutional and legal regulation of the protection of human and civil rights and freedoms, international legal regulation of climate change, risks and threats to public safety, the introduction of digital technologies and global climate policy and energy are considered.

The design of a multiple-unit microscopy system for automated analysis of biomaterials is considered. The system is equipped with tools for automatic adaptation at all stages: optimization of hardware configuration to achieve the maximum speed of scanning for a given group of analysis techniques; selection of the fastest scanning mode taking into account the properties of each slide; adding data to the training sample of analyzed images from an expert database filled by the users in the process of development/upgrading of automatic analyzers of the multiple-unit system.

A method for measuring a gas flow rate is proposed based on ultrasonic sounding of the turbulent flow in a pipe with subsequent cross-correlation processing of signals passed through the flow in two pipe sections. It has been shown that information on the velocity of vortices is obtained from the pipe center due to focusing of ultrasound by a pipe wall. The velocities of vortices were measured using an ultrasonic flow meter and simultaneously by two mutually spaced heat–loss anemometers. Based on the correlation measurements of the time delay it has been shown that the velocity of vortices is less than the maximum flow velocity in the center measured using the Pitot–Prandtl tube. The possibility of measuring the volumetric gas flow rate using the data on the speed of vortices has been demonstrated.

The influence of the operating conditions of ring-shaped bundle force elements made of TiNi alloy on the temperature range of shape-memory effects is considered. By adjusting the mechanical load, the functional mechanisms may be operated in specific temperature intervals.

Experience gained from the operation of nuclear power plants shows that emergencies or incorrect actions of the personnel may give rise to water hammer phenomena, which exert additional impacts on the pipelines and equipment. Condensation-induced water hammer (CIWH) is one of the most destructive kinds of water hammer. Experimental studies of CIWH were carried out in a number of scientific organizations around the world. The main features of the experimental facilities used in the world are considered. For studying the CIWH phenomena occurring in a horizontal channel, a special experimental test facility was set up in 2018 at the Elektrogorsk Research and Engineering Center for Nuclear Power Plants’ Safety (EREC). The facility’s test section and the parameters of experimental regimes are described. Fifty-two experiments were carried out on the facility under different initial and boundary conditions for three values of the water flowrate supplied to the facility (1, 3, and 5 t/h), two values of water temperature (30 and 60°С), and two values of vapor pressure in the test section (0.6 and 1.0 MPa). In all experiments, CIWH phenomena were recorded. As an example, one experimental regime was considered in detail, and the CIWH occurrence mechanism is described proceeding from the readings of pressure and level gages and temperature sensors. The described experimental regime was modeled using the RELAP5 and WAHA thermal-hydraulic codes. The effect that the size of nodalization diagram cells and the integration time step have on the computation results is analyzed. The significant amount of experimental points obtained from the study can be used for setting up a database for validating computer codes.

А method of geometric calculation of a new type of planetary rotary hydraulic machines (PRGM) with satellite stands is developed. The method includes the steps of: 1) calculation of the initial round-link mechanism; 2) calculation of non-round links of the PRGM with outstretches; 3) construction and integration of three-dimensional design system COMPAS-3D fragments of crenellated crowns corresponding to the phases of abutments and lifting-lowering satellites; 4) correction of the toothed contours to eliminate the phenomenon of mismatch of satellite centers with the points of intersection of the trajectories of these centers in their movement relative to the rotor and stator. PRGM with satellite stands are designed to operate as vacuum pumps, compressors and pneumatic motors.

Compression of a fiber array with a deuterated target mounted on its axis is studied at the Angara-5-1 facility (3.5 MA, 100 ns). Cylindrical arrays with an initial diameter of 12 mm made from polypropylene fibers with a diameter of 13.4 µm are used. The number of fibers varied from 30 to 120. The target with the density of 0.08–0.2 g/cm3 and the diameter of 1 mm was made on the basis of deuterated polyethylene. A 10‑frame ultra-high-speed X-ray camera, optical slit scans, an integral X-ray pinhole camera, vacuum X-ray diodes, a crystal spectrograph, and neutron detectors are used to measure the plasma parameters in the Z‑pinch. It is found that the dynamics of plasma compression and evolution of local plasma formations, which are sources of neutrons and soft X-ray emission in the energy range of E > 150 eV, depend on the load configuration: the number of fibers, diameter, and density of the deuterated target. Efficient compression of the liner plasma, high concentration and temperature of the compressed target state, as well as the highest neutron yield (8 × 109 neutron/pulse) are observed in experiments with arrays with the fiber number of 60, inside which the target with the diameter of 1 mm and density of 0.2 g/cm3 was placed. The electron density and temperature of the hot plasma in local formations are estimated as ne ≈ 1021 cm–3, Te ≈ 1 keV, respectively. The average neutron energy was 2.6 ± 0.2 MeV. The intensity of the plasma formation $$\dot {m}$$ [in µg/(cm2 ns)] of polypropylene fibers under the action of the discharge current of the facility is determined in experiments with fiber arrays.

A structural feature of planetary-rotor hydraulic machines (PRHM) is the presence of floating satellites. The satellite forms kinematic pairs with the rotor and stator, which, depending on the applied forces, can change their class. In PRHM with “standouts” of satellites intended for gas media, the kinematic satellite-stator pair operates at critically high values of the pressure angle. Under the influence of the pressure force of the working medium, the satellite, taking up the radial clearance in the gearing, is shifted towards the rotor and pressed against it on both sides of the tooth, and the satellite-stator pair becomes a single-moving pair of class 4. The resulting satellite offset further worsens the conditions for transmitting motion in the satellite-stator pair. As a result, there is a probability of jamming of the mechanism, accompanied by unacceptable deformations, and the satellite's exit from engagement with the stator. From the point of view of the theory of mechanisms and machines, this means that the system loses its structural stability and goes into an undesirable structural state. The article studies the conditions under which inertial forces, overcoming the pressure forces of the working medium, press the satellite against the stator. This eliminates the situation when a kinematic pair characterized by a critically high pressure angle is single-moving. As a result of the performed dynamic analysis, calculated dependencies are obtained that allow determining the rotor rotation speed that provides more reliable operation of the PRHM.

The generation of accelerated electron beams in a high-current Z-pinch formed by the implosion of wire cylindrical tungsten arrays on an Angara-5-1 facility is studied. The most intense characteristic and bremsstrahlung X-ray radiation of fast electrons is recorded from the central region of the pinch at the pin-ching stage. The transverse size of the radiation source in the characteristic tungsten radiation Lα is ~1.5‒1.8 mm, which is close to the transverse size of the radiation source in the soft X-ray emission (1‒1.5 mm). The current of accelerated electrons generated during the implosion of the wire array and the formation of a pinch is on the order of the Alfven current (IA). This result is consistent with the estimate of the current of accelerated electrons made from the measured characteristic radiation intensity Lα of tungsten under the assumption that the mean free path of fast electrons in a pinch is on the order of its length.

The article proposes a method for geometric calculation of gear links of planetary mechanisms in which the central wheels of external and internal gearing have the same number of teeth. The key to solving the problem is the existing possibility of a large positive displacement of the tool when machining the crown with internal involute teeth. The calculation used the formulas GOST 16532–70 and GOST 19274–73, arranged in a certain sequence. The planetary mechanisms under consideration underlie the new volumetric rotary hydraulic machines.

We have studied the fracture problem of layered media under combined dynamic loading. The effect of background harmonic vibrations on the amplitude of the main force pulse is analyzed. The features of fracture from such a combined action are demonstrated using a simple 2D model (a circular membrane on an elastic base). As the condition of adhesive layer rupture, the incubation time criterion is used. It is shown that the threshold amplitude of breaking action can be substantially reduced by correctly choosing the excitation frequency even for low intensities of the background field.

This article describes the experimental and theoretical studies of the mechanisms of failure of ABS polymer in the range of strain rates of 10–4–103 s–1 at different temperatures of testing (from an ambient temperature of 23 to 100°C). The alteration of the type of failure as a function of the strain rate and temperature is analyzed. Based on the structure–time approach, a model of the temperature–rate superposition is proposed.

The paper presents modelling of acoustic cavitation inception. The model is based on the structural-temporal approach, which has shown a predictive effectiveness in considering various transient processes. The presented calculations were performed for four different liquids at a high-frequency vibration and across a wide temperature range. The predictions of the presented theoretical model were validated by comparison with the experimental data, and good agreement was demonstrated.

The implosion of combined loads consisting of an outer wire (fiber) array and inner cylindrical target was studied experimentally at the Angara-5-1 facility (3.5 MA, 100 ns) at currents of up to 3.5 MA. The experiments were carried out with 12- and 20-mm-diameter outer arrays made of 15-μm-diameter aluminum wires, composite arrays made of aluminum wires and 25-μm-diameter kapron fibers, and arrays made of kapron fibers with a 1-μm-thick aluminum coating. The number of wires varied from 10 to 40. The targets were made of agar-agar or low-density deuterated polyethylene. The parameters of the Z-pinch plasma were determined using the Angara-5-1 diagnostic complex, which included optical streak cameras, X-ray frame cameras, X-ray detectors, X-ray pinhole cameras, neutron detectors, and a mica-crystal X-ray spectrograph. It is established that the plasma compression dynamics and the formation of local plasma structures generating neutrons depend on the load configuration: the array diameter, the number of wires (fibers), and the diameter and density of the target. The most efficient compression and the highest plasma parameters (the compression ratio and plasma temperature), as well as the highest neutron yield, were achieved in experiments with 12-mm-diameter aluminum wire arrays inside which a 1-mm-diameter deuterated target with a mass density of 0.3 g/cm3 was installed As a result of collision of the bulk of the array mass with the inner target, a compact pinch with a diameter of ≈0.5 mm forms. The pinch formation is accompanied by the generation of a soft X-ray pulse. The development of MHD instabilities in the pinch plasma results in the formation of multiple hot spots (HSs) on the pinch axis with a typical size of 200–300 μm and an electron temperature of 0.4–0.7 keV. The HS formation is accompanied by emission of neutrons with a mean energy of 2.7 ± 0.2 MeV. The maximum neutron yield achieved in these experiments was 2.6 × 1010 neutrons/shot.

The basics and average jumpers of the rotor and the body are studied, which perform the following functions: provide autonomous work of two sections; carry out autonomous operation of circulation of high and low pressure alkaline; is a frame in which other parts are held to support all functions of the high pressure feeder; support the difference in pressure between the sections. Thus, indicative drawings of the wear of the working surfaces of the rotor and the shell between the windows are formed by the action of alkali in the gap, and its value (at a constant gap) depends on the length of the gap. hus, indicative drawings of the wear of the working surfaces of the rotor and the shell between the windows are formed by the action of alkali in the gap, and its value (at a constant gap) depends on the length of the gap. With a minimum clearance gap between the rotor sections and the feeder housing, the flow rate and the flow rate of the alkali are maximal, and at the maximum length of the gap the flow rate and the flow rate of the alkali are minimal and, consequently, the wear is small. Due to the sinusoidal gap change law, the uneven wear of the working surfaces of the rotor and the body along the length of the circle can be explained.It has been established that on the two working surfaces of the rotor and the body there is a hydro-abrasive wear due to leakage of alkali in the mobile gap and shock hydraulic abrasive wear as a result of the formation of hydraulic shocks in the rotor pocket. The values of these types of wear depend on the time of compensation gap. Compensation for wear on these polling stations is higher than at other polling stations.The nature of the wear and tear of the bases and middle jumpers of the rotor and the body is revealed. The value of this wear is linear in time and its size is comparable to wear on other sections with compulsory micro-impulse gap compensation and not comparable (much less) when compensating for the critical gap. Wear on the bases and mid-joints of the rotor and the body occurs under the influence of hydraulic wear with the forced transfer of solid particles to the friction zone. With an uneven height of 8-10 microns and a minimum clearance of 50-100 microns, abrasive particles are constantly and coercive at these gaps due to cyclic hydraulic shocks. The presence of abrasive particles in the friction zone results in the destruction of both the particles itself and intercontact friction pairs of the surfaces of the bases and middle jumpers of the rotor and the case. As a result, there is a new kind of abrasive wear – hydro-abrasive deterioration in a narrow slit with the forced passage of solid particles into the friction zone., Исследованы основания и средние перемычки ротора и корпуса, которые выполняют следующие функции: обеспечивают автономную работу двух секций; осуществляют автономную работу циркуляции щелочи высокого и низкого давлений; являются каркасом, на котором удерживаются остальные детали, обеспечивающие выполнение всех функций питателя высокого давления; поддерживают разность давлений между секциями. Таким образом, индикаторные рисунки износа рабочих поверхностей ротора и корпуса между окнами формируются под действием протечки щелочи в зазоре, а его величина (при постоянном зазоре) зависит от длины зазора. При минимальной длине зазора между участками ротора и корпуса питателя расход и скорость протечки щелочи максимальный, а при максимальной длине зазора расход и скорость протечки щелочи минимальные и, следовательно, износ небольшой. За счет синусоидального закона изменения зазора можно объяснить неравномерный износ рабочих поверхностей ротора и корпуса по длине окружности.Установлено, что на двух рабочих поверхностях ротора и корпуса имеет место гидроабразивный износ за счет протечек щелочи в подвижном зазоре и ударный гидроабразивный износ в результате образования гидроударов в кармане ротора. Величины этих видов износа зависят от времени компенсации зазора. Компенсация износа на этих участках выше, чем на других участках.Установлена природа изнашивания оснований и средних перемычек ротора и корпуса. Величина этого износа имеет линейный характер во времени и его величина соизмерима с износом на остальных участках при ПМКТКЗ и не соизмерима (намного меньше) при ККЗ. Износ на основаниях и средних перемычках ротора и корпуса происходит под действием гидравлического износа с принудительным поступлением твердых частиц в зону трения. Имея высоту неровностей 8-10мкм и минимальный зазор в пределах 50…100 мкм, в эти зазоры за счет циклических гидравлических ударов постоянно и принудительно поступают абразивные частицы. Наличие абразивных частиц в зоне трения приводит к разрушению как самих частиц, так и межконтактных фрикционных пар поверхностей оснований и средних перемычек ротора и корпуса. В результате имеет место новая разновидность абразивного износа – гидроабразивный износ в узкой щели при принудительном поступлении твердых частиц в зону трения., Досліджено основи і середні перемички ротора і корпусу, які виконують наступні функції: забезпечують автономну роботу двох секцій; здійснюють автономну роботу циркуляції лугу високого і низького тисків; є каркасом, на якому утримуються інші деталі, що забезпечують виконання усіх функцій живильника високого тиску; підтримують різницю тисків між секціями. Таким чином, індикаторні рисунки зносу робочих поверхонь ротора і корпусу між вікнами формуються під дією протікання лугу в зазорі, а його величина (при постійному зазорі) залежить від довжини зазору. При мінімальній довжині зазору між ділянками ротора і корпусу живильника витрата і швидкість протікання лугу максимальні, а при максимальній довжині зазору витрата і швидкість протікання лугу мінімальні і, отже, знос невеликий. За рахунок синусоїдального закону зміни зазору можна пояснити нерівномірний знос робочих поверхонь ротора і корпусу по довжині кола.Встановлено, що на двох робочих поверхнях ротора і корпусу має місце гідроабразивне зношування за рахунок протікань лугу в рухливому зазорі та ударне гідроабразивне зношування у результаті утворення гідроударів у кишені ротора. Величини цих видів зношування залежать від часу компенсації зазору. Компенсація зношування на цих дільницях вища, ніж на інших дільницях.З’ясовано природу зношування основ і середніх перемичок ротора та корпусу. Величина цього зношування має лінійний характер у часі і його величині порівнянна зі зношуванням на інших ділянках при примусовій мікропоштовховій компенсації зазору і не порівнянна (набагато менше) при компенсації критичного зазору. Зношування на основах і середніх перемичках ротора та корпусу відбувається під дією гідравлічного зношування з примусовим надходженням твердих часток у зону тертя. Маючи висоту нерівностей 8-10 мкм і мінімальний зазор у межах 50-100 мкм, у ці зазори за рахунок циклічних гідравлічних ударів постійно та примусово надходять абразивні частки. Наявність абразивних часток у зоні тертя призводить до руйнування як самих часток, так і міжконтактних фрикційних пар поверхонь основ і середніх перемичок ротора та корпусу. У результаті має місце новий різновид абразивного зношування – гідроабразивне зношування у вузькій щілині при примусовому надходженні твердих часток у зону тертя.

Experimental and theoretical data for the strength performance of 1230 aluminum alloy under tension in the quasi-static and dynamic ranges of loading parameters are presented. Using the structural temporal approach and the sign-perturbed sums algorithm, the feasibility of raising the strain rate of a specimen by decreasing its geometrical size has been estimated.

Test results are presented for an additive material prepared of acrylonitrile-butadiene-styrene on a 3D printer. Dynamic tension experiments have been carried out using a tower-type drop hammer with an accelerator. Data obtained from different specimens demonstrate that high-strain-rate tensile experiments are feasible if the working part of the specimen is decreased. A theoretical analysis of test data using the incubation time criterion has been performed, and it has been found that analytical results are in good agreement with experimental data.

The influence of background ultrasonic field on the ultimate dynamic strength of adhesive joints is studied using fracture mechanics analysis. Winkler foundation-type models are applied to describe the cohesion zone, and the incubation time fracture criterion is used. The challenging task is to study whether relatively weak ultrasound is able to decrease the threshold values of the external impact load depending on a joint model, such as an “elastic membrane” or “beam” approximation, and various boundary conditions at the ends. The specific task was to investigate the case of short pulse loading through application of time-dependent fracture criterion instead of the conventional principle of critical stress. Three different load cases, namely, step constant force, dynamic pulse, and their combination with ultrasonic vibrations, were also studied. The analytical solution to the problem demonstrates that background vibrations at certain frequencies can significantly decrease threshold values of fracture impact load. Specific calculations indicate that even a weak background sonic field is enough to cause a significant reduction in the threshold amplitude of a dynamic short pulse load. Additionally, non-monotonic dependency of threshold amplitude on pulse duration for weak background field was observed, which demonstrates the existence of optimal regimes of impact energy input. Moreover, this phenomenon does not depend on the way in which the beam edges mount, whether they are clamped or hinged, and it could be applied for micro-electro-mechanical switch design processes as an additional tool to control operational regimes.

Results of mechanical tests, especially in dynamics, obtained under similar input conditions always have a statistical scatter. Currently, there is no generally accepted engineering approach to the correct assessment of critical stresses for a material under dynamic loads. For example, there is no clear understanding of how many specimens need to be tested to estimate a specific ultimate stress for a specific impact rate. The present study enhances the applicability of the randomized algorithm of Sign-Perturbed Sums to solve the mentioned problem of the dynamic strength evaluation under typical restrictions on experimental results such as few numbers of data points with unknown random noises. The combination of the incubation time criteria and this new probabilistic approach permits to estimate accurately material strength parameters: the critical failure stress and the incubation time with a given level of confidence. Comparative analysis of developing approach and different modifications of the scaling law obtained by Kimberly and Ramesh showed that both models are well agreed with empirically observed data. Experimental data of dynamic test on split Hopkinson pressure bars and a drop tower setup for different quasi-brittle materials are taken to demonstrate advantages of the new method. It is shown that incubation time of failure and critical stress values of certain materials can be estimated with a high level of confidence. These results can be used to optimize experimental studies and develop new standards for dynamic testing of materials.

The possibility of control over the deformation and strength properties of annular structures by choosing temperature intervals of their operation is demonstrated. Identical mechanical actions on “metal muscles” at different temperatures results in considerable changes in their strength potentialities. A wire of diameter 2 mm made of Ti–Ni 50.6 at % alloy is tested.

The mechanical properties of the additive material prepared from acrylonitrile–butadiene–styrene plastic are studied experimentally on a 3D printer in the quasi-static and dynamic regimes. The strength curve describing the nonlinear dependence of the critical stress on the strain rate is constructed using the incubation time. The characteristic incubation time τ is determined by comparing the theoretical curve with the experimental data.

—A technique of ultrasonic action on ring-shaped titanium nickelide samples, which stimulates the shape memory effect, is described. The possibility of ultrasound-induced operation of ring-shaped force elements is shown.

Experiments at the KGU test facility, devoted to condensation induced water hammers (CIWH) were analysed with the WAHA code. Test section of the KGU test facility is slightly inclined horizontal pipe of 3 m length and of 64 mm inner diameter. Subcooled water was supplied to the pipe inlet, pipe outlet was connected to separator vessel. Upper part of separator vessel was connected to steam source. Experiments were performed for different system pressure, different water subcooling and different mass flow rate of water supply. The performed experimental study of CIWH showed that in the investigated range of parameters, the development of CIWH occurs in different ways. At the stage of water propagation along the filled with steam horizontal pipe, water hammer was not observed. At the stage of free drainage of water from the outlet end of the pipe, water hammer was realized only when the water was sufficiently subcooled. At the stage of the water level rise in the horizontal pipe, water hammer occurred in all tests. At the last stage of filling the upper part in the separation vessel, there were small water hammers due to the collapses of the remaining steam bubbles. Numerical modelling of these experiments with the WAHA code revealed the shortcomings of the interphase heat transfer model developed for this code, which have a noticeable effect on the numerical solution.

At the present time, the methods for the measurement and prediction of the dynamic strength of materials are complicated and unstandardized. An experimental data processing method based on the incubation time criterion is considered. Only a finite number of measurements containing random errors and limited statistical information are usually available in practice, since dynamic tests are laborious, and every individual test requires a lot of time. This strongly restricts the number of applicable data processing methods unless we are satisfied with approximate and heuristic solutions. The method of sign-perturbed sums (SPS) is used for the estimation of finite-sample confidence regions with a specified confidence probability under the assumption of noise symmetries. It is shown that several experimental points are sufficient to determine the strength parameter with an accuracy acceptable for engineering calculations. The applicability of the proposed method is demonstrated in the processing of a number of experiments on the dynamic fracture of rocks.

A new approach is proposed to the geometric synthesis of noncircular gears for a rotary hydraulic machine. The corresponding procedure employs universally available mathematical software and standard graphics programs.

Dynamics and spectral transmission of Al plasma produced by extreme ultraviolet (EUV) irradiation of 0.75-μm thick Al foil is investigated. The EUV radiation with the peak power density in the range of 0.19–0.54 TW/cm2 is provided by Z-pinch formed by W multiwire array implosion in the Angara-5-1 facility. Geometry of the experiment ensures that there are no plasma fluxes from the pinch toward the Al foil and plasma. The same EUV source is used as a back illuminator for obtaining the absorption spectrum of Al plasma in the wavelength range of 5–24 nm. It comprises absorption lines of ions Al4+, Al5+, Al6+, Al7+. Analysis of relative intensities of the lines shows that those ions are formed in dense Al plasma with a temperature of ∼20 eV. Dynamics of Al plasma has been investigated with transverse laser probing. We have also performed radiation-gas-dynamics simulations of plasma dynamics affected by external radiation, which includes self-consistent radiation transport in a plasma shell. The simulations show good agreement with an experimental absorption spectrum and with experimental data concerning plasma dynamics, as well as with the analysis of line absorption spectrum. This confirms the correctness of the physical model underlying these simulations.

A method for diagnostics of systolic function of the right ventricle of the heart in patients with cardiovascular disease is proposed. Its application expands possibilities for detecting disorders of the discharge RVfunction using a conventional pulsed wave Doppler ultrasonography.

Dynamic spalling tests have been run on two batches of 30KhN4M steel samples. Experimental data have been processed with the classical technique based on solution of the elastic wave equation. Three samples have been revealed that demonstrated the failure-delay effect under testing. The incubation-time criterion has been used to show the conditions of emergence of failure delay with the example of triangular loading pulses. A rate strength curve has been constructed for the other samples. It has been shown that the limiting strengths under dynamic loads considerably differ for samples from different batches despite the same chemical composition and static strength.

This paper outlines the results of experimental study of the dynamic rock failure based on the comparison of dry and saturated limestone samples obtained during the dynamic compression and split tests. The tests were performed using the Kolsky method and its modifications for dynamic splitting. The mechanical data (e.g. strength, time and energy characteristics) of this material at high strain rates are obtained. It is shown that these characteristics are sensitive to the strain rate. A unified interpretation of these rate effects, based on the structural–temporal approach, is hereby presented. It is demonstrated that the temporal dependence of the dynamic compressive and split tensile strengths of dry and saturated limestone samples can be predicted by the incubation time criterion. Previously discovered possibilities to optimize (minimize) the energy input for the failure process is discussed in connection with industrial rock failure processes. It is shown that the optimal energy input value associated with critical load, which is required to initialize failure in the rock media, strongly depends on the incubation time and the impact duration. The optimal load shapes, which minimize the momentum for a single failure impact, are demonstrated. Through this investigation, a possible approach to reduce the specific energy required for rock cutting by means of high-frequency vibrations is also discussed.

A method for processing the results of dynamic spall fracture tests, based on the exact solution of the wave equation, and its commonly used simplified version based on the assumed unique relation between the free surface velocity drop and the ultimate medium fracture stress, are analyzed. Using the considered exact solutions of the wave technique, tensile stress pulses during spalling are determined. The obtained stress levels at the fracture point are compared with the spall strength calculated by the velocity drop technique. The cases of agreement and disagreement of the results obtained using both techniques are shown. By the example of differently shaped loading pulses, possible scenarios of sample fracture are presented, in particular, the probability of the fracture delay effect is shown, which can be lost in the simplified processing method.

The strength of the adhesion joint under the combined vibrational-pulsed loading is considered. Beam and membrane models on elastic foundation is applied to simulate behavior of adhesion zone. The incubation time criterion is used to determine the threshold parameters of a load required to adhesive zone fracture. The solution of the differential equation describing the behavior of the adhesive zone is obtained by the Fourier method. Different types of combination of pulsed loading with high-frequency external fields are considered. It demonstrates that background vibration fields of even low intensity at certain frequencies can significantly reduce these critical values. The dependence of the threshold value of the external pulse on the model parameters is shown. The possible way to control to adhesive joint strength by background vibrational fields is suggested.