Acoustic Wave Propagation Velocity Research Articles

Development of methods for monitoring and predicting the strength of concrete at an early age by acoustic emission method

Introduction. The description of the main results of the research work carried out in JSC Research Center of Construction on the topic “Development of methods for monitoring and predicting the strength of concrete at an early age by acoustic emission method” is given.Aim. The aim of the work is to obtain experimental data for the development of methods for monitoring and predicting the strength of concrete at an early age by acoustic emission.Materials and methods. The research was carried out on concrete mixtures made of heavy and fine-grained concrete with mineral and chemical additives. In the process of concrete hardening the acoustic emission method was used. Acoustic emission monitoring was carried out continuously for several days.Results. According to the results of the study, the most informative parameters of acoustic emission data that correlate with the strength of concrete have been identified. Automated algorithms for concrete strength monitoring have been developed. Based on the results of measuring the propagation velocity of acoustic waves and the decrease in the attenuation coefficient of acoustic signals, as well as the output of these values to the plateau, the periods of completion of setting of concrete mixtures are determined. During the experiments optimal frequency characteristics of acoustic emission sensors were determined.Conclusions. The results of the research allow us to introduce into the practice of construction a new approach for monitoring the strength properties of concrete during its hardening using the acoustic emission method. Proposed approach can be carried out remotely, without the presence of an operator. The advantages of this approach also include its use in hard-to-reach places where the use of other testing methods is difficult.

Mathematical modeling of a new method for processing a seismic signal on the example of a section of the Saratov right bank. Part 2

This paper presents a new method of seismic exploration with two buried receivers on the same vertical, which helps in comparing the experimental seismogram cleared of non-vertical signals with the calculated theoretical seismogram, which depends on the parameters of the layered structure, such as the thickness of the layers, their density, velocity of propagation of longitudinal acoustic waves in rock, and seismic quality factors of media. The method of least squares aided in the search for the global minimum of the discrepancy function of the calculated and experimental seismic pulse waveforms. The implementation of the algorithm for solving the inverse seismic problem was carried out in the MatLab software package. The construction of a theoretical seismogram includes the calculation of the spectrum of the input impulse, calculation of the frequency dependences of the reflection coefficients and the passage of waves at the interfaces of rocks with different physical parameters, the calculation of the shape of the seismic impulses received by the receivers. A comparison of the calculated and real parameters of the geological structure obtained in the COMSOL Multiphysics software package shows that the developed algorithm results in obtaining a seismogram that practically coincides with the experimental seismogram corresponding to the real rock section, with appropriate geological parameters of media, such as thickness, density and propagation velocity of acoustic waves, as well as quality factors.

ASSESSMENT OF METHODS FOR DETERMINING THE NATURAL GAS HEAT OF COMBUSTION

The shortage of fuel and energy resources, the increase in natural gas prices and the continuous increase in gas consumption indicate the relevance of the issues of measuring the natural gas amount and assessing its quality indicators. Ukraine is implementing the European methodology for calculating gas consumption based on its quality and efficiency. The problem of determining the gas quality in Ukraine requires a thorough assessment and research.
 The main physical and chemical indicator of the natural gas quality, which characterizes its energy value, is the specific volumetric gas heat of combustion. The value of this parameter differs for different gas fields. The gas heat of combustion determines the efficiency of its use both in everyday life and in industry.
 The aim of the work is to analyze the main methods for determining the calorific value of natural gas.
 The gas heat of combustion is determined by calorimetric, chromatographic and correlation methods.
 The calorimetric method is characterized by the complexity of the measurement process, complete combustion of the test gas, and long term process. This ensures the objectivity of the results, which is based on taking into account the moisture content of the gas and the presence of non-combustible components in it.
 The basis of the chromatographic method is the separation of the components of a gas sample in a chromatographic column. The result is a chromatogram that shows the percentage composition of hydrocarbons in the gas. The characteristic properties of the method are the identification of a wide range of components and the repeatability of the results.
 When using correlation methods for determining the heating value of natural gas, various physicochemical parameters of samples are measured (such as total hydrocarbon concentration, heat capacity, acoustic wave propagation velocity, carbon dioxide concentration, thermal conductivity, dielectric constant, dynamic viscosity, and others).
 Correlation dependence is based on the choice and association of such parameters. This dependence is studied on different test gas mixtures and allows us to determine the empirical dependence. The mixtures correspond to gases with different calorific values. The obtained empirical dependence is used to register the heat of combustion of real natural gas. The paper evaluates the features of these methods application and instruments based on them.

Vibrational, thermodynamic and acoustic properties of AgAlS2 crystal

First-principles calculations of vibrational properties of AgAlS2 crystal have been performed for the first time. The phonon dispersion and phonon density of states were calculated. Phonon dispersion curves disclose dynamical stability of the system. The group-theoretical classification of vibrational modes has been done and classification according to selection rules of modes active in infrared and Raman spectra has been performed. Raman and infrared spectra of AgAlS2 were calculated within the DFPT method. The LO-TO splitting of the infrared modes are reported. The effective Born charges for constituent atoms of the crystal were calculated and analyzed. Thermodynamic functions such as enthalpy, entropy, free energy and heat capacity at constant volume are obtained. The propagation velocities of longitudinal and transverse acoustic waves in the crystal were calculated for the (100) and (001) directions. The anisotropy coefficients are calculated and anisotropy of the propagation speed of acoustic waves in AgAlS2 crystal is analyzed.

Diagnosis of fire damage depth in mortar using nonlinear harmonic method and scanning airborne ultrasound technique

Abstract This paper reports the effectiveness of a new fire depth diagnosis of mortars using airborne ultrasonic source scanning method and non-linear harmonic method(NHM). We propose a model of fire damage mortar in which Young's modulus gradually decreases from the surface layer at high temperature during fire. In addition, based on the model, we also propose to diagnose the depth of fire damage from changes in the propagation velocity of surface acoustic waves. In addition, in order to verify the theory of the proposed method, the propagation speed of surface acoustic waves propagating in the fire damage mortar is simulated by FEM analysis, and the possibility of diagnosing the depth of fire damage is obtained. Finally, we measure the propagation velocity of surface acoustic waves using an experimental sample simulating the fire damage mortar model described above, and obtain results with almost the same tendency as that of FEM analysis.

Novel fractal acoustic metamaterials (FAMs) for multiple narrow-band near-perfect absorption

In this work, we introduce fractal acoustic metamaterials (FAMs), in thicknesses ranging from 5 (λ/69) to 25 mm (λ/18), which are observed to provide multiple narrow-band low-frequency absorptions of acoustic signals. The fractal structures used in this work are carefully designed and fabricated using a side branch Helmholtz resonator design, making these structures easily tunable to multiple frequencies. Using different sizes of the side branches distributed in a fractally oriented configuration onto a plane rigid baseplate, the propagation velocity of acoustic waves is slowed down considerably. There is also a shifting resonating response of the structures toward lower frequencies (<1600 Hz). These FAM structures exhibit no dependence on the acoustic traverse length, as is otherwise commonly seen in coiled meta-structures and others. In order to achieve a near-perfect sound absorption behavior, the geometry of the structure is theoretically ascertained and validated numerically and experimentally. Significant emphasis has been placed on the associated physical mechanism modulating the loss of intensity of the incident acoustic signals. Moreover, with regression analysis performed on a response surface-based optimization scheme (using Design Expert 11 software), the geometric parameters are determined in a way that the absorption demonstrates a narrow-band characteristic at a frequency of 1 K Hz. We have shown in this work the tunability aspect of the various absorption frequency bands through appropriate designs of the FAM. It opens up wide application possibilities of multiple frequency sound absorptions (acoustic cloaking).

CHARACTERIZATION OF TRANSVERSE CYLINDRICAL CAVITIES IN WOODEN BLOCKS OF THE SPECIES Cedrela odorata USING NON-DESTRUCTIVE ULTRASOUND TESTS

The main objective of the present work was to characterize the transverse cylindrical cavities of Cedrela odorata wood blocks using the non-destructive ultrasound techniques (NDT). The dispersions of acoustic wave propagation velocity (AWV) were measured and, considering the anisotropic structure of the wood, the Hankinson model was used for modeling with 2D graphics. The results showed strong dispersion in the frontal direction depending on the diameter of the cavities, in addition to good linear relationships between them for the cavity axis. Therefore, the results support the use of NDT ultrasound techniques to assess deteriorated structural elements such as historical monuments.

Reflection of waves from a mobile elastic layer in a multimode waveguide

Waveguide structures are used to transmit energy and information signals in a wide range of wavelengths and, in terms of wave-guiding physical properties, usually have mutual (identical) properties in forward and backward directions. The asymmetry of the structure and external influences can often cause non-reciprocity of structures for waves, propagating in mutually opposite directions (this property, although limited, is already used in the so-called nonreciprocal devices of microwave, EHF and optical ranges such as ferrite valves, circulators, phase shifters). At the same time, the nonreciprocal properties of wave-guiding structures, independent of their physical nature, were not considered. It is found, that the motion of the medium filling the acoustic waveguide leads to nonreciprocity of its parameters in the forward and backward directions. The degree of nonreciprocity is proportional to the velocity of the medium. The velocity of the medium also affects the propagation velocity of acoustic waves and leads to a change in the critical frequencies or critical wavelengths of the waveguide modes. As the velocity of the medium increases, the number of modes for which the propagation condition is satisfied increases as well.

Acoustic Wave Propagation in Standing Trees - Part II. Effects of Tree Diamter and Juvenile Wood

The objective of this study was to investigate the effects of tree diameter and juvenile wood on acoustic wave propagation in standing trees. Two-layer tree models with various diameters and proportions of juvenile wood were constructed to examine the effects of these two factors on propagation patterns and velocity of acoustic waves. The simulation results and analysis indicated that acoustic wave propagation in trees is dependent on both tree diameter and propagation distance. In the context of time-of-flight (TOF) acoustic measurement on standing trees with a test span of 1.2 m, when tree diameter is 10 cm or less, or slenderness is twelve or greater, wave propagates as quasi-plane waves in tree trunk, and the tree velocity determined using the TOF method is then comparable to the log velocity measured using the acoustic resonance method. When tree diameter is 40 cm or larger, or slenderness is three or less, wave propagates as dilatational waves in the tree trunk; thus, the three-dimensional wave equation should be considered for wood property prediction. When tree diameter falls between 10 and 40 cm or slenderness falls between 3 and 12, wave propagation is in a transitional phase. Mathematical models were developed to convert the tree velocity in the transition mode to the resonance velocity. It was found that juvenile wood content resulted in a 113-m/s reduction in acoustic velocity. In addition, our analysis indicated that wave propagation in standing trees is controlled by the wood properties of entire cross section, not just the outerwood. Therefore, the wave velocity measured on standing trees reflects the global properties of the wood between the two measuring points.

Measurement of the Second-Order Material Constants of Lanthanum-Gallium Tantalate (LGT) Through Ultrasound.

Lanthanum-gallium tantalate (LGT) is a member of the LGX crystal family (langasite, langanite, and langatate) known for high-quality factor and stability at higher temperatures. These characteristics enable filters and sensors for use in harsh environments. Accurate values for the second-order material constants are required for electromechanical modeling of such devices. A sufficient set of bulk acoustic wave (BAW) propagation velocities have been measured in cube-shaped samples to obtain the full set of second-order elastic and piezoelectric material constants along with the experimental uncertainties. The cross correlation method was used to accurately measure the time-of-flight (TOF) values between the first two back-wall echoes under a constant room-temperature environment. The calculated BAW velocities and extracted material constants show good agreement with earlier work.

Features of amplitude frequency characteristics of ABS plastic 3D printed metamaterial sample

In this study, we investigated the acoustical properties of custom-designed phononic crystal-like acoustic metamaterials 3D printed from ABS plastic. The elastic properties of these metamaterials were studied experimentally and numerically. The metamaterial consisted of a set of plane parallel lattices the number of which could vary in different samples. Each lattice in the sample consisted of 16 parallel square rods. The amplitude-frequency characteristics (AFC) of the fabricated metamaterial sample were measured in the frequency range (35-100) kHz using longitudinal acoustic waves both in air and water. The propagation velocities of longitudinal and shear acoustic waves of ABS plastic itself were measured prior to the experiment. The band gaps (stop bands) were detected and investigated while measuring AFC of the metamaterials. We have found that the increase in the number of lattice layers in the sample led to the band gap acoustic wave attenuation coefficient increase along with the band gap narrowing, while the central frequency of the band gap remained the same. The numerical simulation of the sample frequency response was carried out in COMSOL. The results of experimental studies and numerical simulations were in satisfactory agreement. We have also investigated the ultrasound scattering diffraction pattern of the sample. The obtained results can be used in solid-state physics and material science, to create materials with controlled frequency-dependent acoustic properties.

On the determination of acoustic emission wave propagation velocity in composite sandwich structures

This work focuses on the rapid determination of Acoustic Emission (AE) wave propagation velocity in composite laminate and sandwich structures using a closed-form formula. Firstly, a classical closed-form model proposed in the literature is extended to determine the acoustic wave velocity in any direction in a composite laminate or sandwich structure; then a corrective factor has been defined to improve the calculation accuracy; finally, a parameter, called correlation ratio has been introduced to describe the relation between acoustic wave velocity in the composite skin and that in the sandwich panel. This strategy has been validated by two types of composite sandwich panels: one is honeycomb sandwich structures with CFRP composite laminate skins; the other is balsa sandwich with GFRP skins. It is demonstrated that acoustic wave velocity in the sandwich is dominated by the skin property, namely the elastic modulus of the skin, the density of the constituents, the core and skin thickness. Moreover, only by measuring the velocity in one direction, the velocity in any direction of composite structures can be predicted accurately and quickly. This work lays the first foundations for the establishment of numerical and experimental models necessary to improve the damage localization of composite structures.

GEOMETRIC PARAMETERS OF BORED PILES DETERMINED BY DUAL CHANNEL ACOUSTIC MEASUREMENTS

Surface acoustic measurements in examining pile foundations is increasingly used in practice, as it is an effective tool for the measuring the length and defects of piles. However, this method for diagnostics of monolithic pile structures, for example, bored piles, can lead to significant measurement errors. This is because the propagation velocity of acoustic waves in a bored pile is usually calculated theoretically, and many factors affecting the propagation velocity of acoustic waves are not taken into account. According to earlier research, dual channel acoustic measurements used to determine the length of bored piles, makes it possible to accurately calculate the propagation velocity of acoustic waves and, accordingly, the pile length. It is shown that dual channel acoustic measurements applied to bored piles allow detecting with sufficient accuracy such defects as cross-sectional deviations of the pile shaft along its length.

Pre-Earthquake and Coseismic Ionosphere Disturbances of the Mw 6.6 Lushan Earthquake on 20 April 2013 Monitored by CMONOC

In order to study the coupling relationship between large earthquakes and the ionosphere, the techniques of ionosphere data acquisition were refined by the Crustal Movement Observation Network of China (CMONOC) to detect the pre-earthquake ionospheric abnormal and coseismic ionospheric disturbances (CID) of the Mw 6.6 Lushan earthquake on 20 April 2013. Based on the regional ionosphere maps (RIMs) derived from the Global Positioning System (GPS) observations of CMONOC, the ionospheric local effects near the epicenter of the Lushan earthquake one month prior to the shock were analyzed. The results show that the total electron content (TEC) anomalies appeared 12–14 (6–8 April), 19 (1 April), and 25–27 (24–26 March) days prior to the Lushan earthquake, which are defined as periods 1, 2, and 3, respectively. Multi-indices including the ring current index (Dst), geomagnetic planetary (Kp) index, wind plasma speed (Vsw) index, F10.7, and solar flares were utilized to represent the solar–terrestrial environment in different scales and eliminate the effects of solar and geomagnetic activities on the ionosphere. After the interference of solar–terrestrial activity and the diurnal variation in the lower thermosphere were excluded, the TEC variations with obvious equatorial ionospheric anomaly (EIA) in period-1 were considered to be related to the Lushan earthquake. We further retrieved precise slant TECs (STECs) near the epicenter to study the coseismic ionospheric disturbance (CID). The results show that there was clear STEC disturbance occurring within half an hour after the Lushan earthquake, and the CID propagation distance was less than the impact radius of the Lushan earthquake (689 km). The shell models with different altitudes were adopted to analyze the propagation speed of the CID. It is found that at the F2-layer with the altitude of 277 km, which had a CID horizontal propagation velocity of 0.84 ± 0.03 km/s, was in accordance with the acoustic wave propagation velocity. The calculated velocity acoustic wave from the epicenter to the ionospheric pierce points of this shell model was about 0.53 ± 0.03km/s, which was also consistent with its actual velocity within the altitude of 0–277 km. Affected by the geomagnetic field, the CID mainly propagated along the southeast direction at the azimuth of 190°, which was almost parallel to the local magnetic line.

Flat acoustics with soft gradient-index metasurfaces

There is an important demand for the manufacture of materials allowing a precise control of the propagation of acoustic waves. This depends, among other things, on the speed of propagation of the waves in the material, which is expressed by the so-called acoustic index: n = C L,ref / C L,mat where C L,ref and C L,mat are the propagation velocities of acoustic waves in a reference medium (water for us) and in the material, respectively. We have recently shown that silicone-based porous polymer materials possess exceptionally high and scalable propagation indices, which can be tuned by a precise control of the polymer's mechanical properties and porosity [1]. Our materials are obtained using an emulsion templating method coupled with a drying process that will be described in my presentation. Using this experimental approach, we were able to produce materials with an acoustic index gradient allowing, among other things, the development of a flat acoustic lens [2]. I will present the synthesis and the characterization of these materials as well as their acoustic properties. [1] A. Kovalenko, M. Fauquignon, T. Brunet, and O. Mondain-Monval, “Tuning the sound speed in macroporous polymers with hard or soft matrix,” Soft Matter 13, 4526–4532 (2017). [2] Y. Jin, R. Kumar, O. Poncelet, O. Mondain-Monval, and T. Brunet, “Flat acoustics with soft gradient-index metasurfaces”, Nat. Commun. (to be published).

In-Phase and Quadrature Analysis for Amplitude and Frequency Modulations Due to Vibrations on a Surface-Acoustic-Wave Resonator.

Surface-acoustic-wave resonators (SAWRs) have found widespread usage in various modern consumer radio frequency (RF) communications electronics, such as cellular phones, wireless devices, GPS devices, frequency control, and sensing applications. External mechanical vibrations modify an SAWR relative dimensions and the substrate's elastic properties, which alter the device's acoustic wave propagation velocity and ultimately cause the SAWR RF response to change. Detecting vibrations are desirable for dynamic strain or vibration sensing applications, whereas external mechanical excitations can result in spurious signals which compromise SAW-based filters and oscillators used in RF communication, frequency control, and sensors targeting measurands such as temperature and pressure. Therefore, understanding and characterizing the SAWR's response to external vibration is relevant for establishing device operation, and assisting in device design and packaging to either mitigate the impact of vibrations for RF communications and frequency control or enhance the SAWR response for sensor applications. This paper presents an in-phase and quadrature demodulation technique (I-Q technique) to detect, quantify, and analyze the effect of externally induced mechanical vibrations on an SAWR. The I-Q technique disclosed reveals that the mechanical vibrations cause both frequency and amplitude modulations of the SAWR RF response, which can be separated by this technique. Furthermore, the procedure also allows the direct measurement of vibration frequencies and vibration magnitude. The technique, measured results, and analysis established here provide a better understanding of the impact of external mechanical vibrations on an SAWR response, which is important in contemporary communications, frequency control, and sensing applications.

Investigations of the Structural and Strain-Stress State of the Rails of Current Production by the Acoustic Elasticity Method

Представлены результаты экспериментальных измерений остаточных напряжений в элементах рельса, измеренных электромагнитно-акустическим структуроскопом СЭМА с использованием метода акустоупругости. Оценка внутренних напряжений произведена также в отдельных элементах рельса. Настройка чувствительности структуроскопа СЭМА и определение коэффициента акустоупругой связи выполнены в лабораторных условиях путем создания в отрезке рельса напряженного состояния одноосного сжатия в направлении продольной оси на испытательной машине Instron 300DX. Отмечена высокая чувствительность и достоверность измерений с погрешностью определения механических напряжений до 2 МПа и соответствие зарегистрированных структуроскопом механических напряжений нагрузке рельса, реализуемой на стенде. Остаточные напряжения, определяемые акустоупругим методом по измеряемой разнице времени пробега двух ортогонально поляризованных сдвиговых волн на участке от головки до подошвы и обратно, являются усредненными по сечению рельса и несут информацию о величине продольных напряжений в рельсе. Диапазон разброса измеренных в лаборатории остаточных напряжений в отрезках рельсов составил 49…67 МПа. С ростом сжимающей нагрузки происходит уменьшение скорости головной волны на всех измеряемых участках рельса. Для относительной оценки остаточных напряжений в отдельных элементах рельса выполнены измерения скорости распространения акустических волн по головке, шейке и подошве, показавшие, что остаточные напряжения в продольном направлении рельса, как правило, носят сжимающий характер для головки и растягивающий - для шейки.

Propagation of Ship-Generated Noise in Shallow Sea

Abstract Contamination of sea environment by noise and any energy radiated to water constitutes today a problem to which more and more attention is paid, in view, a.o., of consequences of an impact of these factors onto marine fauna. European Union has introduced a directive by which EU countries are made responsible to undertake efforts aimed at reaching a good envirenmental status of European seas by 2020. A main source of underwater noise is sea transport of any kind. Propagation of underwater acoustic disturbances in the Baltic Sea highly differs from the course of the phenomenon in a deep sea. Model of spherical propagation cannot be applied to this case in view of water environment limitation by seabed and free water surface, i.e. a reduction of the problem to wave propagation in a water layer of the depth comparable with acoustic wave length. This paper is aimed at demonstration of possible assessment of range of acoustic disturbances generated by a ship sailing in shallow sea, by using a method described in the work [13]. The research was made on the basis of results of own measurements of underwater noise produced by ships in the Gdansk Bay area. An important factor which decIdes on a range of underwater disturbances is a kind of seabed sediments. In this paper there are presented results of numerical investigations based on real data dealing with noise produced by a selected floating unit (ship) for selected characteristic spectral components. The simulations were conducted for the shallow sea model of definite physical parameters such as acoustic wave propagation velocity, geometrical dimensions (water depth) and seabed acoustic parameters as well.

Acoustic Transducers as Passive Cooperative Targets for Wireless Sensing of the Sub-Surface World: Challenges of Probing with Ground Penetrating RADAR.

Passive wireless transducers are used as sensors, probed by a RADAR system. A simple way to separate the returning signal from the clutter is to delay the response, so that the clutter decays before the echoes are received. This can be achieved by introducing a fixed delay in the sensor design. Acoustic wave transducers are ideally suited as cooperative targets for passive, wireless sensing. The incoming electromagnetic pulse is converted into an acoustic wave, propagated on the sensor substrate surface, and reflected as an electromagnetic echo. According to a known law, the acoustic wave propagation velocity depends on the physical quantity under investigation, which is then measured as an echo delay. Both conversions between electromagnetic and acoustic waves are based on the piezoelectric property of the substrate of which the sensor is made. Investigating underground sensing, we address the problems of using GPR (Ground-Penetrating RADAR) for probing cooperative targets. The GPR is a good candidate for this application because it provides an electromagnetic source and receiver, as well as echo recording tools. Instead of designing dedicated electronics, we choose a commercially available, reliable and rugged instrument. The measurement range depends on parameters like antenna radiation pattern, radio spectrum matching between GPR and the target, antenna-sensor impedance matching and the transfer function of the target. We demonstrate measurements at depths ranging from centimeters to circa 1 m in a sandbox. In our application, clutter rejection requires delays between the emitted pulse and echoes to be longer than in the regular use of the GPR for geophysical measurements. This delay, and the accuracy needed for sensing, challenge the GPR internal time base. In the GPR units we used, the drift turns out to be incompatible with the targeted application. The available documentation of other models and brands suggests that this is a rather general limitation. We solved the problem by replacing the analog ramp generator defining the time base with a fully digital solution, whose time accuracy and stability relies on a quartz oscillator. The resulting stability is acceptable for sub-surface cooperative sensor measurement.

The effect of the level of total sodium deposited in the myocardium on its stiffness

To determine a relationship between the level of total sodium in the myocardium to its stiffness. The investigation enrolled 18 hypertensive patients who had suddenly died; their mean age was 40±10 years; mean waist circumference, 102±12.5 cm; height, 170±7.7 cm; myocardial mass, 319±53 g. The variation in the myocardial level of total sodium averaged 211.7±37.5 (min, 71.5; max, 226.17) mmol/l. The sodium level was ascertained to be affected to the greatest extent by myocardial mass (SS=3615.56; p=0.00029) and age at death (SS=1965.568; p=0.0029), whereas gender and smoking had a considerably lower impact (SS=778.584; p=0.03). A univariate regression analysis showed that there was a relationship between myocardial sodium levels and the thickness of the anterior wall of the left ventricle (β=0.94; p=0.000001; r2=0.88), that of the anterior wall of the right ventricle (β=0.82; p=0.000021; r2=0.66), and that of the interventricular septum (β=0.94; p=0.000001; r2=0.89). The wall thickness of the myocardium was established to depend on its sodium level (SS=21813.89; p=0.000001; r2=0.88): the higher sodium amount in the myocardium, the thicker its walls. The average velocity of acoustic wave propagation was 6.24±0.51 m/sec. A significant correlation was observed between sodium concentrations in the myocardium and its stiffness (β=0.72; p=0.00062; r2=0.49). The level of sodium deposited in the myocardium, which is directly related to dietary sodium intake, is significantly correlated with myocardial stiffness. It can be assumed that the elevated level of sodium deposited in the myocardium is an independent factor that changes the stiffness of the myocardium and appears to influence the development of its diastolic dysfunction.