Ultrasonic Velocity Measurements Research Articles

Damage to monumental masonry buildings in Hatay and Osmaniye following the 2023 Turkey earthquake sequence: The role of wall geometry, construction quality, and material properties

Damage to monumental masonry buildings in Hatay and Osmaniye following the 2023 Turkey earthquake sequence: The role of wall geometry, construction quality, and material properties

Reassessment of Birch's Law on hcp‐Fe From Ultrasonic Sound Velocity Measurement and Implications on the Velocity Profiles of Earth's Inner Core

AbstractWe performed in situ X‐ray diffraction and ultrasonic sound velocity measurements on hcp‐Fe up to 15 GPa, 873 K in a multi‐anvil apparatus. The elastic moduli and their pressure and temperature derivatives were determined by fitting the velocity and density data to the third‐order finite strain equations, yielding KS0 = 169.0(57) GPa, KS0′ = 5.4(6), (∂KS/∂T)P = −0.031(3) GPa/K, G0 = 104.5(27) GPa, G0′ = 1.7(2), (∂G/∂T)P = −0.060(2) GPa/K. Within the experimental P‐T range, we find significant temperature effect on the density‐velocity (ρ − VP or S) relations and caution the use of the temperature‐independent Birch's law for extrapolation to core conditions. Furthermore, temperature‐induced velocity decrease is more significant in VS than in VP, offering a possible explanation for the high Poisson's ratio in the core. Extrapolations based on our results together with previous experimental data suggest that VP of hcp‐Fe aligns with PREM at Earth's core conditions, while Vs and density are approximately 10% and 2.7% higher than PREM, respectively.

Cyclic loading behavior of concrete with thermally-induced damage

The paper reports a study on concrete specimens that were subjected to constant amplitude, low-strain cyclic (LSC) and high-strain cyclic (HSC) tests to evaluate their cyclic behavior after they had been subjected to either ambient or elevated temperatures. Parameters examined included maximum normal stress, dynamic modulus, and extent of damage observed in specimens. An equation is proposed to help quantify the extent of damage in specimens, which accounts for both thermal and cyclic loading effects. Ultrasonic Pulse Velocity (UPV) measurements were also used to quantify the damage in both the LSC and HSC tests. Results show that losses in compressive strength and dynamic modulus are greater in cases with higher temperature exposures due to thermally induced damages. Also, cyclic characteristics of the specimens were found to be significantly influenced by the strain amplitude used in cyclic loading tests.

Velocity Measurements of Powdered Rock at Low Confining Pressures and Comparison to Lunar Shallow Seismic Velocity

AbstractSeismic methods will be useful for future lunar near‐surface characterization, and high‐fidelity elastic models will be required to aid interpretation of seismic observations. To develop an elastic lunar near‐surface model, we performed ultrasonic velocity measurements of lunar regolith simulant at low confining pressure and developed a rock physics model calibrated to these measurements. Grain contact models based on Hertz‐Mindlin theory produce accurate results at high confining pressure (i.e., several hundred meters or more burial depth) but historically fail to predict observed velocities in unconsolidated media at low pressure. Therefore, we heuristically modified existing models to fit our measured data over a range of porosities and confining pressures. To compare with Apollo 14 and 16 active seismic experiments, we used our new heuristic rock physics model to produce lunar subsurface velocity profiles. We performed ray tracing through our velocity profiles to calculate seismic traveltime, which results in good agreement with first arrivals interpreted from the Apollo experiments. Our model suggests a slightly higher velocity‐pressure dependence than inferred from in situ measurements, which may be due to porosity reduction in the lunar regolith from impact‐induced and natural vibrations.

Simulation of Shear and Tensile Fractures Using Ductile Phase Field Modelling with the Calibration of P Wave Velocity Measurement and Moment Tensor Inversion

AbstractThe appropriate understanding and formulation of rock discontinuities via FEM is still challenging for rock engineering, as continuous algorithms cannot handle the discontinuities in rock mass. Also, different failure modes of rock samples, containing tensile and shear failure, need to be computed separately. In this study, a novel double-phase field damage model was introduced with two independent phase field damage variables. The construction of the proposed model follows the thermodynamics framework from the overall Helmholtz free energy, with elastic, plastic and surface damage components. The proposed model is calibrated via traditional damage variables, based on ultrasonic wave velocity measurement and acoustic emission monitoring, and both show great consistency between simulation results and laboratory observations. Then the double-phase field damage model is applied to COMSOL software to simulate microcrack propagation in a pre-fractured rock sample. Both lateral and wing cracks are observed in this study, manifested as shear- and tensile-dominated cracks. We also observed different microcracking mechanisms in the proposed numerical models, such as tensile and shear cracking, the influence of plastic strain and the percolation between tensile and shear microcracks. Overall, this study provides valuable insights into the mechanics of microcracking in rocks, and the proposed model shows promising results in simulating crack propagation.

Exploring Ultrasonic Velocity and Compressibility Analysis for Various Edible Oils: A Comparative Study

This study presents a comparative analysis of ultrasonic velocity and compressibility properties in a selection of commonly used edible oils, namely mustard oil, olive oil, coconut oil, groundnut oil, and soybean oil. Understanding the acoustic and compressibility characteristics of these oils is of significant interest due to their widespread culinary and industrial applications. Ultrasonic velocity measurements were conducted using a precision ultrasonic velocity analyzer, while compressibility analysis was performed through precise density measurements. Our findings reveal distinct differences in ultrasonic velocity and compressibility among the various oils. This comparative study contributes to our understanding of the acoustical and compressibility characteristics of edible oils, offering potential applications in food processing, quality control, and product development. Additionally, the findings may have implications in the field of biomedical and industrial applications where these oils are utilized.

Unveiling the synergistic effect of Cd doping on structural, optical, mechanical, and γ-ray shielding characteristics of zinc lead silicate glass

Using the traditional melt quenching process, the glass series of xCdO-(5-x) ZnO-35Pb3O4-60SiO2, where x = 1–5 mol%, were created. The X-ray diffraction method was utilized to investigate the non-crystallinity of the glasses that were created. The densities of the fabricated glasses increased from 5.91 to 6.655 g/cm³. Electronegativity (ΔX), bond density (nb), and field strength (F) were calculated. ΔX decreased while nb and F increased with the supply of Cd ions. The optical characteristics Eg, n, αo, εr, χ(3), n2, M, T and more have been investigated. We found that a change in cadmium concentration in the fabricated system influenced all the optical parameters. The mechanical properties, including elastic moduli, have been investigated alongside ultrasonic velocity measurements. The experimental results demonstrated a strong dependence of calculated parameters on increasing CdO concentration. The observation indicates an increase in the elastic moduli with the increasing CdO concentration. Radiation shielding factors were estimated using EpiXS program. μL, HVL, MFP, Zeff, Neff, EBF and EABF for gamma energy between 15 and 15,000 KeV have been investigated. The results indicate that these parameters are affected by the introduction of CdO content into the glass network. The sample ZPSCd5 exhibits the highest radiation shielding parameters among the studied glass samples.

Evolution of self-healing performance of UHPC exposed to aggressive environments and cracking/healing cycles

This paper investigates the resilience of UHPC's self-healing capabilities under aggressive environmental conditions and cracking/healing cycles. UHPC specimens ‘with a double-edged wedge splitting geometry were made, incorporating a commercial crystalline admixture (Penetron Admix®). The evaluation of UHPC's healing capacity involved subjecting pre-cracked samples to three different water immersion conditions: tap water, saltwater, and geothermal water. The closure of cracks during different curing periods was meticulously recorded using optical microscopy. Furthermore, specialized tests, including ultrasonic pulse velocity (UPV) measurements and splitting tensile tests, were conducted to quantify the recovery of mechanical properties. The results reveal that extended exposure results in a gradual closure of cracks, where salt water and geothermal water exhibit lower self-healing capabilities. Self-healing improves after the 1st crack/self-healing cycle but decline rapidly after the 2nd cycle. Mechanical property is strongly correlated with the extent of self-healing, and all samples display varying degrees of stiffness recovery, with the most pronounced recovery occurring after the 1st cycle. However, following the 2nd cycle, the stiffness recovery values decrease due to repeated loading, resulting in increased damage and a reduced number of reactive particles, thereby compromising self-healing and stiffness recovery. Despite enduring multiple instances of crack damage, UHPC samples still exhibit notable toughness recovery, underscoring the enduring efficacy of the self-healing mechanism even in challenging conditions.

Determination of the anisotropy in mechanical properties of laser powder bed fusion Inconel 718 by ultrasonic testing

ABSTRACT This study aims to investigate the effects of build direction on the as-fabricated microstructure and mechanical properties of Inconel 718 specimens manufactured via the Laser Powder Bed Fusion (L-PBF) technique. The microstructures and mechanical properties of the specimens were characterized via SEM, EBSD,ultrasonic wave velocity measurements, hardness and tensile tests. For the as-fabricated condition, the highest tensile strength (1114 MPa) was obtained with the horizontally built specimens while the vertically built ones have the highest 40% elongation. The computational analysis produced results that closely aligned with the measured yield strength values of L-PBFed samples. Additionally, a strong correlation was observed between the hardness values and longitudinal ultrasound velocity of L-PBF Inconel 718 specimens. Consequently, the non-destructive ultrasonic evaluation provided valuable insights into the anisotropy of mechanical properties, complementing information obtained from conventional tensile tests.

Durability properties of lightweight concrete with ceramic mould casting waste

As economies and industrialisation have grown, the foundry industry has produced a significant amount of ceramic mould casting waste (CMCW). To promote resource utilisation, this study investigates recycling CMCW as a partial replacement for lightweight aggregates in lightweight concrete. The durability of lightweight concrete mixes with varying CMCW content was studied using surface electrical tests, ultrasonic pulse velocity measurements, non-steady-state accelerated chloride penetration tests and carbonation resistance experiments. The results indicate that a lightweight concrete containing 80% CMCW exhibited greater density and uniformity, greater resistance to chloride ion penetration and better resistance to carbonation. These findings suggest that CMCW can be an effective and sustainable replacement for lightweight aggregate in lightweight concrete, improving durability and environmental performance. This research contributes to the development of sustainable construction materials and provides insights for the use of CMCW in the foundry industry.

Review of Density and Ultrasonic Velocity of Various Complexes and Its Applications

This review paper delves into the fundamental principles, measurement techniques, and diverse applications of ultrasonic velocity and density. Ultrasonic velocity serves as a crucial parameter in various fields such as materials science, acoustics, and medical diagnostics whereas density is used for identifying substances, quality control, analyzing mixtures, assessing purity, explaining buoyancy, determining concentrations, calibrating instruments, monitoring pollution, and understanding reactivity. This paper provides an in-depth exploration of the underlying concepts, different measurement methods, and the wide-ranging applications of ultrasonic velocity and density. The ultrasonic velocity and density data have also been used to evaluate various acoustic parameters such as isentropic compressibility, apparent isentropic molar compressibility, solvation number of the solute and relative association. Ultrasonic velocity measurements are found to be useful for on-line assessment of the extent of degradation of mechanical properties associated with precipitation of intermetallics. Keywords: Density, Ultrasonic velocityThis review paper delves into the fundamental principles, measurement techniques, and diverse applications of ultrasonic velocity and density. Ultrasonic velocity serves as a crucial parameter in various fields such as materials science, acoustics, and medical diagnostics whereas density is used for identifying substances, quality control, analyzing mixtures, assessing purity, explaining buoyancy, determining concentrations, calibrating instruments, monitoring pollution, and understanding reactivity. This paper provides an in-depth exploration of the underlying concepts, different measurement methods, and the wide-ranging applications of ultrasonic velocity and density. The ultrasonic velocity and density data have also been used to evaluate various acoustic parameters such as isentropic compressibility, apparent isentropic molar compressibility, solvation number of the solute and relative association. Ultrasonic velocity measurements are found to be useful for on-line assessment of the extent of degradation of mechanical properties associated with precipitation of intermetallics. Keywords: Density, Ultrasonic velocity

Effect of Microwaves on the Rapid Curing of Metakaolin- and Aluminum Orthophosphate-Based Geopolymers.

This paper deals with the influence of microwaves on the hardening and curing of geopolymer binders synthesized from metakaolin or aluminum orthophosphate with sodium silicate solution as the activator. Pure geopolymer pastes as well as geopolymer mortars were considered. The variable parameters were the modulus of the sodium silicate solutions (molar ratio of SiO2 to Na2O: 1.5, 2.0 and 2.5) and the Si/Al ratio (3/1 and 2/1). Selected samples were cured in a microwave oven until hardening, so the curing time depended on the mixture. For comparison some samples were cured at ambient temperature. To investigate the influence of microwave radiation on the reaction kinetics, isothermal heat flow calorimetry, ultrasonic velocity measurements and rheological investigations into the variation of curing temperature were used. In addition, the mechanical properties of the cured samples were characterized. The results show that microwave curing only takes a few minutes, so it is the most time-saving method. Key factors influencing the geopolymer reaction under microwave radiation are the raw materials as well as the Si/Al ratio. Metakaolin-based geopolymer binders are more stable than those based on aluminum orthophosphate, especially regarding their salt efflorescence. Microwave radiation is an efficient method to accelerate the geopolymer reaction.

Ultrasonic velocity measurements of backscattered acoustic waves for monitoring the enzymatic coagulation of milk

In this work, the milk coagulation process was monitored by a nondestructive ultrasonic technique. Three analysis methods were used to calculate ultrasonic wave velocity and assess their effectiveness in tracking the physicochemical changes: Cross-correlation, Spectrum ratio, and Smoothed Pseudo-Wigner-Ville transform. The obtained results show a consistency between the velocity measurements made by these three methods, with a steady increase observed during coagulation and both phases are visible. The time-frequency method was most effective, showing a clearer transition between the two phases. This study suggests that non-destructive ultrasonic techniques with time-frequency analysis could be advantageous for monitoring milk coagulation and ensuring dairy product quality.

Experimental analysis of biocementation technique for sealing cracks in concrete water storage tanks

Water supply systems are vital infrastructures that provide an indispensable public service to society. An important percentage of water losses is caused by the development of cracks in water storage tanks, so efficient crack sealing repair works must be investigated. Biocementation has been used with good results for sealing cracks in many construction concrete infrastructures (e.g., buildings), as an alternative to standard materials, such as polymeric resins and cement mortars. This research aims at the experimental evaluation of biocimentation effectiveness in terms of watertightness for sealing cracks structures in contact with pressurized water, to be further applied to repair cracks in water storage tanks. Biocementation treatment is applied in cracks artificially created in small rectangular concrete plates 4 cm thick, with three crack widths (i.e., 0.1, 1 and 10 mm) to cover different real cases in which the repair with this technique is viable. The 10 mm width cracks were filled with sand before the treatment. Different rounds of bacteria Sporosarcina pasteurii are applied, being the efficiency of the treatment investigated by performing watertightness tests through variable water head tests starting at 10 kPa (1 m of water). Dissolution is discarded through measurements of ultrasonic pulse velocities before and after the watertightness tests and the results are explained by images of thermographic camera. The presence of biocement is confirmed by mineralogical analysis of the precipitate extracted from the cracks after breaking the plates through bending tests. Obtained results are very promising since the biocement precipitated can completely stop water flow in the 0.1 mm cracks and, for the cracks with 1 mm and 10 mm widths, the treatment can reduce the initial flow rate, on average, by 95% and 98%, respectively. The performance of the 10 mm width cracks previously filled with sand was similar to that of the 1 mm cracks, where no sand was used. The material strength recovered after the treatment is not as good as desirable: although a maximum recovery of 95.5% of the initial strength (average values) is found for the smallest crack width and it was almost null for the other two crack widths. These results demonstrate that the technique is effective when watertightness is required, but not when material strength must also be recovered. Further research is required to investigate the maximum water pressures that can be applied to each case, eventual effects of biocimentation on water quality and the durability of the treatment.

Ultrasonic pulse velocity and artificial neural network prediction of high-temperature damaged concrete splitting strength

To examine the integrity of any structure following a fire, assessments of the impact of high temperatures on concrete are essential, particularly its decreased in tensile strength. Destructive examinations, such as the extraction of concrete cores, can pose significant cost and safety challenges, particularly when applied to structures that have already sustained damage. Consequently, for assessing damaged concrete, non-destructive in-situ tests are the favored approach. This study aims to develop an artificial neural network model utilizing data from ultrasonic pulse velocity measurements. The model's purpose is to assess the tensile splitting strength of concrete subjected to elevated temperatures, ranging from 200 to 800 °C. The splitting strength investigation showed that increasing the exposure temperature from 200 to 800°C results in splitting strength reduction of 15 to 75% respectively. Also, the ultrasonic pulse velocity experienced a reduction of 85% when the exposure temperature reaches 800 °C. In addition, the results of the artificial neural network model indicated that ultrasonic pulse velocity and temperature data were sufficient to reasonably forecast the tensile splitting strength of concrete. The developed artificial neural network model has a coefficient of determination (R2) of 0.943, a mean absolute relative error (MARE) of 5.028, and an average squared error (ASE) of 0.000907.

STUDY OF THE RELATIONSHIP BETWEEN FATIGUE CHARACTERISTICS AND ELASTIC MODULUS OF METASTABLE AUSTENITIC STEELS

This work is devoted to studying the influence of cyclic deformation on the elastic moduli of metastable austenitic steel. The estimated calculation of the modules of the strain-induced martensite and the modules of the matrix of the material (austenite) in the Voigt approximation. The modulus calculations were made according to the ultrasonic wave velocity measurements taking into account changes in the density of the material due to the difference in the volumes of the unit cells of the matrix and the ??-martensite. The volume fraction of ??-martensite and its change during cyclic deformation were determined by the eddy-current method. The influence of the strain cycle amplitude on the increase in the volume fraction of martensite was studied. The dependences of the relative change in Young's modulus, shear modulus, volume compression modulus on the number of loading cycles for metastable steel 12Kh18N10T are given. Relationships between the moduli change and the characteristics of cyclic loading of steel are obtained: the hardening of the material and the energy density in the cycle, used to calculate the service life using the methods of deformable solid mechanics. Studies shown that the critical change in the modules corresponding to the appearance of a microcrack depends on the strain cycle amplitude.The maximum change in the modules of metastable steel 12Kh18N10T was 4.5%; that by an order more than in steels that don't undergo phase transformations. A high degree of correlation between the change in elastic moduli and the fatigue characteristics of metastable austenitic steel is revealed: the hardening of the material and the energy density in the cycle. Correlations between the fatigue life of 12Kh18N10T steel and the change in elastic modulus – shear modulus and Young's modulus are obtained, which makes it possible to assess the state of the studied steel based on acoustic measurements.

Experimental study of seismic dispersion: influence of clay mineral content

SUMMARY We conducted an extensive study on the elastic properties of Opalinus Clay and the overlying and underlying rock formations, which range in the overall clay mineral content from nearly 0 to 60 wt.%. Our laboratory experiments focused on seismic and ultrasonic frequencies to determine the extent to which seismic dispersion affects elastic parameters and seismic wave velocities. The results comprise the static stiffness from undrained triaxial cycles (axial–confining stress: 8–10 MPa), the dynamic stiffness at seismic frequencies (0.5–143 Hz), intrinsic attenuation (0.5–20 Hz), compressional velocity measurements (0.5–2 Hz) and ultrasonic velocity measurements (250 and 500 kHz). We compared these laboratory results to in situ sonic logging measurements to assess the role of frequency in measured elastic parameters. The results suggest a notable correlation between clay mineral content and dispersion. Specifically, high clay mineral content leads to increased dispersion, even within the seismic frequency band. The overall dispersion of P-wave velocity in the frequency range from 1 Hz to 500 kHz is up to 16%. This frequency dependency is crucial when establishing a relationship between sonic well log data and static stiffness for geomechanical modelling. The results are discussed with respect to possible dispersion mechanisms, including the role of bound water in clay.

Identification of Aggregation Processes in Hexamethylenetetramine Aqueous Solutions: A Comprehensive Raman and Acoustic Spectroscopic Study Combined with Density Functional Theory Calculations

Raman scattering has been employed to study in detail the concentration dependence of the vibrational modes for hexamethylenetetramine (HMTA) aqueous solutions. The formation of protonated and/or aggregated species has been clarified by comparing the experimental with the theoretically predicted vibrational spectra by means of quantum mechanical calculations. The analysis has shown that the vibrational modes of the solutions arise from a contribution of the vibrational modes of the HMTA self-aggregates and hetero-aggregates of HMTA with water molecules that are formed in the low- and intermediate-concentration regions, respectively. The protonation of HMTA is ruled out due to the large differences between the experimental and the theoretically calculated spectra of the protonated molecules of HTMA in the fingerprint region. In the low-concentration solutions, the hetero-aggregation reaction of HMTA with water is the dominant mechanism, while at higher concentrations, a self-aggregation mechanism occurs. Ultrasonic absorption and velocity measurements were carried out for hexamethylenetetramine aqueous solutions. The acoustic spectra reveal the presence of only one single Debye-type relaxation process that is assigned to the aggregation mechanism of HMTA. The sound absorption data follow two different dependencies on the HMTA mole fraction. The crossover 0.018 mole fraction signifies two separate regions with distinct structural characteristics. The relaxation mechanism observed in dilute solutions was attributed to hetero-association of HMTA with water molecules, while at higher concentrations, the observed relaxation process was assigned to the self-association reaction of HMTA molecules. This structural transformation is also reflected in several physicochemical properties of the system, including the kinematic viscosity, the mass density, the sound speed and the adiabatic compressibility of the HMTA aqueous solutions. The combination of vibrational and acoustic spectroscopies with molecular orbital calculations allowed us to disentangle the underlying processes and to elucidate the observed relaxation mechanism in the HMTA aqueous solutions.

Evaluation of Self-Healing Properties of OPC-Slag Cement Immersed in Seawater Using UPV Measurements

In this study, OPC-slag cement, which partially replaced ground granulated blast-furnace slag (GGBFS), was immersed in seawater at three temperatures and the self-healing effect was evaluated through ultrasonic pulse velocity (UPV) measurement. In addition, test specimens without cracks were immersed and cured in the same seawater environment to compare the characteristics of UPV and crack-healing effects. The results of the study showed that increasing the GGBFS content or immersion temperature improved the healing effect up to 30 days after immersion, but there was no significant effect after 30 days of immersion. In a saltwater environment, a thick layer of brucite was deposited near the crack, blocking the inflow of seawater and impeding the formation of additional healing material. According to visual observation, the crack entrance appears to have been covered and healed by the brucite layer. However, the brucite layer in the crack area increases the UPV in the early stages of immersion, which may lead to a misconception that it is self-healed, and there is a possibility of overestimating the self-healing effect.

Development of sweep frequency ultrasonic interferometer for high precision velocity measurement in liquids.

An ultrasonic interferometer with variable separation between the transducer and reflector is widely used for the measurement of ultrasonic propagation velocity in liquids. The inherent limitation of such an interferometer is due to the mechanical movement of its reflector for ultrasonic wavelength measurement in a liquid medium. It is observed that the ultrasonic velocity measurement precision is adversely affected at higher frequencies compared to lower ones. For instance, in our experimentation, a standard deviation of ±21.5m/s (±1.43%) was obtained for velocity measurement at 1.84MHz with the consideration of two consecutive maxima, which increases drastically to ±76.8m/s (±5.12%) at 9.4MHz. These measurements can significantly be improved by considering many maxima and averaging for wavelength estimation. However, it still requires design attention and improvement, particularly for higher frequencies. In this article, a sweep-frequency based ultrasonic interferometer design with a fixed separation for liquid characterization is proposed and described. This technique overcomes the limitations of mechanical movement systems and also provides a better and uniform precision for lower as well as higher frequencies. The functionality of the developed sweep frequency method was tested in water, carbon tetrachloride, ethylene glycol, and glycerol, which shows good agreement with literature values. The velocity measurement in double distilled water by the developed technique at 1Hz sweep resolution has shown an improved standard deviation of ±0.74m/s (±0.05%) at 9.4MHz.