Acoustic Resonance Spectroscopy Research Articles

Enhancing the durability performance of thermally damaged concrete with ground-granulated blast furnace slag and fly ash

This study investigates the effectiveness of ground-granulated blast furnace slag (GGBFS) and fly ash in improving the durability of concrete specimens subjected to thermal damage. Multiple techniques, including nonlinear impact resonance acoustic spectroscopy (NIRAS), compressive strength, X-ray diffraction, and thermogravimetry, are employed to capture the physical and chemical phenomena resulting from a temperature elevation of 200, 400, 600, and 800 °C. The experimental results demonstrated that replacing cement with fly ash (20 wt%) and GGBFS (40 wt%) yields significant mitigation of microcracking development, highlighting their potential as agents for enhancing concrete durability under high-temperature exposure. Notably, the hysteresis nonlinearity parameter (α) measured using NIRAS exhibits a high sensitivity for detecting the transition from micro to macroscale defects, and the trend of α sufficiently coincides with the results of the mineralogical analyses, confirming the evaporation of free water, dehydration of calcium silicate hydrate (C-S-H), and decomposition of calcium hydroxide (CH).

Mitigating self-desiccation of cement composites via cellulose microfibers: Evidence of the microscopic behavior

Water-saturated cellulose microfibers (CMFs) incorporated into fresh cement composites can mitigate microcracking induced by self-desiccation during drying. This study utilized a nonlinear impact resonance acoustic spectroscopy (NIRAS) technique to elucidate the mechanism underlying the CMF-driven mitigation of self-desiccation. The hysteresis nonlinearity parameter (α) from the NIRAS was used to quantify the microstructural changes in three different mixtures (0 0.3 and 1% dosages of CMFs). Computed tomography (CT) compression tests and periodic measurements of mass and resonance frequency were performed to obtain more insights into mitigating self-desiccation. Supported by the collected data the results show a remarkable reduction in α over time confirming high sensitivity of α to the microstructural change. Furthermore the trend of α was consistent with the pore size distribution estimated by the CT test which provides quantitative evidence to support the mitigation of self-desiccation promoted by CMFs. We envision that these findings can be used as guidelines for enhancing the durability of cement composites facilitated by CMFs.

Edge and corner states in two-dimensional finite phononic crystals: Simulation and experimental study

We investigate the mechanical vibration transmission in two-dimensional infinite and finite phononic crystals (PCs). The infinite PC consists of a periodic structure formed by square plates connected to the center of each of their nearest neighbors through a tiny beam. Numerical simulations using finite elements show a wide full bandgap for frequencies between 27 kHz and 32 kHz, approximately. Acoustic resonant spectroscopy was used to measure the PC frequency spectra for the different vibrations, using a finite PC consisting of 8 by 8 cells, which was designed with the same configuration as the infinite one. Experimental results corroborate the existence of a full complete bandgap predicted by the numerical method. However, the width was significantly reduced due to the appearance of edge and corner states. The border states were obtained numerically using a supercell. The measured wave amplitudes and the simulated ones present a great similarity. Some states appear located at the corners of the finite PC demonstrating that zero-dimensional states can also appear in two-dimensional phononic crystals.

Genetic Algorithm-Wavelet Transform Feature Extraction for Data-Driven Acoustic Resonance Spectroscopy

Acoustic Resonance Spectroscopy enables highly accurate measurement of the properties (geometry/material) of a structure based on the structure's natural vibrational resonances. In general, measuring a specific property in multibody structures presents a significant challenge due to the complex overlapping peaks within the resonance spectrum. We present a technique for extracting useful features from a complex spectrum by isolating resonance peaks that are sensitive to the measured property and insensitive to other properties (noise peaks). We isolate specific peaks by selecting frequency regions of interest and performing wavelet transformation, where the frequency regions and wavelet scales are tuned via a Genetic Algorithm. This contrasts greatly from traditional wavelet transformation/decomposition techniques, which use a large number of wavelets at different scales to represent the signal, including the noise peaks, and results in a large feature size, thus decreasing Machine Learning generalizability. We provide a detailed description of the technique and demonstrate the feature extraction technique for example regression and classification problems. We observe reductions of 95% and 40% in regression and classification errors, respectively, when using the Genetic algorithm/Wavelet Transform feature extraction, compared to using no feature extraction, or using Wavelet Decomposition, which is common in optical spectroscopy. The feature extraction has potential to significantly increase the accuracy of spectroscopy measurements based on a wide range of Machine Learning techniques. This would have significant implications for ARS, as well as other data-driven methods for other types of spectroscopy, e.g. optical.

Acoustic Resonance Spectroscopy with an Uncalibrated Microwave Path

Acoustic Resonance Spectroscopy with an Uncalibrated Microwave Path

Assessment of internal curing of cellulose microfibers-incorporated cement composites using destructive and nondestructive methods

Water-saturated cellulose microfibers (CMFs) incorporated into fresh cement composites can facilitate the internal curing, holding a potential for mitigating intrinsic material defects such as microcracks, interfacial transition zones (ITZs), and pores that raise the material nonlinearity. To elucidate the contribution of water supply from CMFs to internal curing process, this study utilizes the nonlinear impact resonance acoustic spectroscopy (NIRAS) technique. Hysteresis acoustic nonlinearity parameter (α) and linear resonance frequency are measured from the NIRAS tests and used to nondestructively quantify the microstructural changes induced by different degrees of internal curing in three different samples (with 0, 0.3, and 1% dosage of CMFs). To get more insight into this phenomenon, other properties including porosity, internal relative humidity (IRH), autogenous shrinkage, compressive strength, and ultrasonic wave velocity are also measured. Evidenced by all measured data, our results confirm that α shows a high sensitivity to the extent of microstructural change in cellulose microfibers-incorporated cement composites, which solely enables capturing time-dependent microstructural changes and thus the discrimination between internal curing effect and development of intrinsic material defects (or material nonlinearity). We believe that this study can lay the foundation for enhancing the durability performance of cement composites via CMFs.

Acoustic Resonance Spectroscopy of Piezoelectric Crystals under Non-Uniform Heating

Acoustic Resonance Spectroscopy of Piezoelectric Crystals under Non-Uniform Heating

Elastometry of clot phantoms via magnetomotive ultrasound-based resonant acoustic spectroscopy

Objective. An ultrasound-based system capable of both imaging thrombi against a dark field and performing quantitative elastometry could allow for fast and cost-effective thrombosis diagnosis, staging, and treatment monitoring. This study investigates a contrast-enhanced approach for measuring the Young’s moduli of thrombus-mimicking phantoms. Approach. Magnetomotive ultrasound (MMUS) has shown promise for lending specific contrast to thrombi by applying a temporally modulated force to magnetic nanoparticle (MNP) contrast agents and measuring resulting tissue displacements. However, quantitative elastometry has not yet been demonstrated in MMUS, largely due to difficulties inherent in measuring applied magnetic forces and MNP densities. To avoid these issues, in this work magnetomotive resonant acoustic spectroscopy (MRAS) is demonstrated for the first time in ultrasound. Main results. The resonance frequencies of gelatin thrombus-mimicking phantoms are shown to agree within one standard deviation with finite element simulations over a range of phantom sizes and Young’s moduli with less than 16% error. Then, in a proof-of-concept study, the Young’s moduli of three phantoms are measured using MRAS and are shown to agree with independent compression testing results. Significance. The MRAS results were sufficiently precise to differentiate between thrombus phantoms with clinically relevant Young’s moduli. These findings demonstrate that MRAS has potential for thrombus staging.

Evaluation of self-healing in concrete using linear and nonlinear resonance spectroscopy

In this study, self-healing in concrete incorporating two types of healing agents, i.e., 1) a self-healing capsule and 2) supplementary cementitious materials with crystalline admixtures, is monitored using linear and nonlinear resonance acoustic spectroscopy techniques. Beam-shaped concrete specimens are prepared using the healing agents, and after 28 days, a single vertical crack with a width ranging from 0.25 to 0.35 mm is generated at the center of the specimens. To monitor the self-healing process in concrete, the samples are vibrated via impact-based excitation methods in the flexural and longitudinal directions, whereas the linear resonance frequency and acoustic nonlinearity parameter α are measured for two months. Additionally, the acoustic nonlinearity parameter is analyzed using two different methods: 1) multiple impacts with manually controlled amplitude, and 2) single impact with artificially controlled amplitude by changing the windowing region in a signal. Test results show that the linear resonance frequency increases up to 86%–97% that of the uncracked condition after 63 days of self-healing. The linear trend of the resonance frequency is correlated significantly with the decrease in the external crack area, but the change in α is affected by the presence of partially filled cracks than by the overall crack area.

Frequency filter for elastic bending waves: Poincaré map method and experiment

Abstract In this work, the Poincaré map numerical method was successfully developed to solve the fourth-order differential equation that describes the flexural vibrations of a beam, within the Timoshenko beam theory. The Euler-Bernoulli continuity conditions were considered, which are valid for frequencies smaller than the critical frequency. As an example, this method was used to design a complex elastic structure, characterized by a flexural frequency spectrum with a broad band gap. Such structure consists of two coupled phononic crystals, which were designed with filling factor values in such a way that in their bending frequency spectra, an allowed band of the first part, overlaps with a band gap of the second one and vice versa. The resulting composed system has a much wider effective gap than its original components, between 4 and 10.5 kHz. This system works as an elastic bending wave filter. Finally, these three structured elastic systems were constructed, and characterized by the acoustic resonance spectroscopy technique. The natural flexural frequencies as well as the corresponding wave amplitudes of each structured beam were measured. The experimental measurements show excellent agreement with the numerical simulation.

Acoustic magnetic resonance spectroscopy of hydrogen nuclei in fluid

We present an analytical study on acoustic magnetic resonance spectroscopy system for hydrogen nuclei in a viscous fluid medium. Magnetic flux density applied to a sample comprising of hydrogen nuclei results in alignment of the magnetic moments along the direction of magnetic field, which precess at Larmor frequency. An acoustic wave applied to the system leads to development of time varying shear forces which can be decomposed into a rotational and a strain component. The rotation of the nuclei around their axes exerts a time varying torque leading to an enhancement of the amplitude of oscillations eventually leading to the generation of radio frequency magnetic fields, which can be used for characterization of a given sample for diagnosis of physiological conditions.

Study of Spatial Distribution of Piezoelectric Properties of ZnO Films by Acoustic Resonator Spectroscopy

Using broadband acoustic resonator spectroscopy, an almost twofold increase in the frequency of optimal excitation of the composite microwave resonator of shear bulk acoustic waves is found when the distance from the substrate to the magnetron axis during the deposition of a ZnO film by magnetron sputtering is changed. The frequency characteristics of the resonator structure are simulated and an explanation of the change in the optimal excitation frequency by the inhomogeneity of the inclination of the ZnO film texture’s axis over the thickness is proposed.

Effects of slow dynamics and conditioning on non-linear hysteretic material assessment using impact resonance acoustic spectroscopy

The microstructural features of heterogeneous and porous materials give rise to unique non-linear dynamic behaviour. The purpose of this work is to investigate the dynamic response of thermally damaged concrete specimens measured by two different techniques: Non-linear Impact Resonance Acoustic Spectroscopy (NIRAS) and new Flipped Accumulative Non-linear Single Impact Acoustic Spectroscopy (FANSIRAS). Specimens were characterised in two different dynamic condition states of the material: relaxed and conditioned. The specimen’s relaxed state indicates that no previous dynamic excitation event ocurred. The conditioned state denotes that the specimen has been dynamically tested before. The NIRAS results show that the non-linear material parameters, αf and αQ, are affected by their previous dynamic history (its conditioning). The recently proposed algorithm, FANSIRAS, extracts from a single resonant signal equivalent results to NIRAS when the specimen is conditioned. In this situation, both parameters αf and αQ were equivalent. The results suggest that new NDT parameters based on non-linear hysteretic parameters can quantify the damage level of thermally treated mortar specimens.

Single-Impact Nonlinear Resonant Acoustic Spectroscopy for Monitoring the Progressive Alkali–Silica Reaction in Concrete

Alkali–silica reaction (ASR) is a ubiquitous cause of concrete degradation. The reaction produces an expandable gel that may cause internal over-stressing and cracking. This paper demonstrates the utility of single-impact nonlinear resonant acoustic spectroscopy (SINRAS) for monitoring the progress of ASR over the course of a standard ASR-susceptibility test. In SINRAS, the transient softening and subsequent recovery of resonance frequency due to one strong impact are analyzed. The performance of SINRAS in monitoring ASR is compared to that of multi-impact nonlinear resonant acoustic spectroscopy (MINRAS), where the gradual resonance frequency shifts caused by impacts of increasing intensity is measured. The changes in standard linear expansion and linear resonance frequency are recorded in parallel. Finally, the sensitivity of measured parameters to sample temperature is investigated. Our findings indicate that SINRAS, while being much simpler and faster to conduct, yields results that strongly correlate to those from MINRAS and even gives an additional parameter describing the rate of recovery. The extracted nonlinearity parameters exhibit good sensitivity and clearly differentiate between concrete with reactive and non-reactive aggregates. Further, this study suggests that the influence of sample temperature on the nonlinearity parameters depends on the level of ASR progression and has to be taken account.

Nonlinear Acoustic Spectroscopy and Frequency Sweep Ultrasonics: Case on Thermal Damage Assessment in Mortar

An exhaustive study on thermal damage of Portland cement-based materials is addressed. Damage carried out at different temperatures on concrete between 40 and $$525\,^{\circ }\hbox {C}$$ were assessed by means of microstructural, physical and nondestructive tests. Microstructural analysis (thermogravimetry and scanning electron microscopy) showed the principal changes of the Portland cement hydrated products for the different analysed temperatures. Compressive and flexural strengths remained constant or even increased at a low heating temperature range, while the mass loss increases. Dilatometry analysis revealed important information about deformation incompatibilities between the paste and the aggregate. These results have been correlated with nondestructive tests: nonlinear impact resonance acoustic spectroscopy (NIRAS) and ultrasonic measures. The dynamic modulus and ultrasonic pulse velocity have closely predicted the linear stiffness decay of the specimens. However, hysteretic parameter from NIRAS analysis exhibited a different trend from stiffness-related parameters, keeping constant until $$250\,^{\circ }\hbox {C}$$ and suffering a huge increasing for 400 and $$525\,^{\circ }\hbox {C}$$ . Ultrasonic attenuation computed with a broadband ultrasonic signal (chirp) revealed interesting information about scattering components inside the material, and is sensitive to interfacial transition zone between aggregate and paste in a large range of frequencies. The correlation between microstructural, mechanical and nondestructive techniques were carried out successfully. Nonlinear vibration and ultrasonic attenuation are non-conventional parameters that gave specific information about a complex damage process, such as a thermal attack in highly heterogeneous materials (e.g. Portland cement composites).

Acoustic resonance spectroscopy based simple system for spectral characterization and classification of materials

Acoustic resonance spectroscopy based simple system for spectral characterization and classification of materials

Resonant Acoustic Tweezing Spectroscopy for Small-Volume Noncontact Assessment of Blood Coagulation

Introduction: Measurement and interpretation of mechanical properties of whole blood and blood plasma are important diagnosis and treatment monitoring of various conditions like coagulopathy, hemophilia, sickle cell disease and many cardiovascular disorders. Many of the current techniques like thromboelastography, micro-viscometry or microfluidic devices used for this purpose require a large sample volume and/or may be prone to measurement errors due to sample contact with device walls. To address these issues, we developed a single-drop non-contact method for blood rheological analysis, referred to as “acoustic tweezing rheometry”. With sample volume as small as 4 μL, our innovative technology has been successfully applied for assessment of whole blood and blood plasma coagulation. Here, we present the extension of this technology to resonant spectroscopic measurement of blood viscoelasticity.Materials and Methods: The schematic of the acoustic tweezing device is shown in (Figure 1A). The standing acoustic wave field between the transducer and reflector generates the acoustic radiation force on the biological sample that traps it in a host fluid (e.g., air). Sample tweezing (force-induced deformation and translational motion of the trapped sample) is achieved by amplitude modulation of the acoustic tweezing signal at high frequency and then decrease the frequency continuously until the lower limit for sample trapping is reached. During this frequency sweep, shape changes of the sample were recorded (Figure 1B) by a photodetector and a high-speed camera (Figure 1A). The amplitude-frequency response of the sample was obtained from raw data analysis, with the amplitude being the maximum deflection of the sample height from its equilibrium value. Dynamic (shear) viscosity and elasticity of the sample were assessed from the quality factor of the amplitude-frequency response (Figure 1C) and the resonance frequency, respectively.Results and Discussion: The quality factor analysis predicted that the dynamic viscosity of commercial normal control blood plasma was 1.5 mPa·s at room temperature, which agreed with previous large-sample-volume measurements. Once re-calcified, the resonance frequency of blood plasma and thus its shear elasticity increased due to clot formation until reaching a plateau in 5 min (Figure 1D). Using this graphical output (referred to as “tweezograph”), the following coagulation parameters can be extracted: clot initiation time, clotting rate, clotting time, and maximum clot elasticity.Conclusions: Resonant acoustic tweezing spectroscopy can accurately measure dynamic viscosity and elasticity of whole blood and blood plasma with a small drop of the sample and without artefacts or measurement errors due to sample contact with device walls. This technique can be applied for rapid assessment of whole blood and blood plasma coagulation.Acknowledgments: This study has been supported by U.S. National Science Foundation grant 1438537, American Heart Association Grant-in-Aid 13GRNT17200013, and Tulane University intramural grants. The acoustic tweezing technology is protected by pending patents PCT/US14/55559 and PCT/US2018/014879. [Display omitted] DisclosuresKhismatullin:Levisonics Inc: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.

Electroacoustic Excitation of Spin Waves and Their Detection due to the Inverse Spin Hall Effect

Abstract—In this paper, we present theoretical and experimental results on the excitation and detection of spin waves and spin currents in multifrequency bulk acoustic wave resonators containing iron–yttrium garnet (YIG) films in contact with the Pt film. Acoustically excited magnetic precession under the resonator conditions was established to produce spin pumping that also has a resonance character. A significant asymmetry in the frequency dependence of the voltage signal detected on the Pt film is revealed with respect to the frequency of the magnetoelastic resonance and is confirmed by theoretical calculations. Acoustic resonator spectroscopy in combination with the electric detection of magnetic dynamics using the inverse spin Hall effect is shown to be of interest for studying the dispersion of spin waves, as well as magnetic and magnetoelastic parameters of ferromagnetic films.

Monitoring the Carbonation-Induced Microcracking in Alkali-Activated Slag (AAS) by Nonlinear Resonant Acoustic Spectroscopy (NRAS)

Abstract This article presents the potential of nonlinear resonant acoustic spectroscopy (NRAS) for noninvasive monitoring of the carbonation progress in alkali-activated slag (AAS) mortars. In the search for sustainable concrete, AAS has emerged as a potential substitute for ordinary portland cement binder. However, carbonation is reported to be an important durability concern for AAS due to the absence of portlandite. In this study, the correspondence between the physical properties and microstructural evolution of sodium silicate-activated slag (SS-AS) and sodium hydroxide-activated slag (SH-AS) mortars were studied over the full course of accelerated carbonation. The measured properties include the following: compressive strength, carbonation depth, porosity, pore size distribution, and phase assemblage. In addition, NRAS was used to track the changes in materials stiffness (linear resonance frequency) and hysteretic nonlinearity (amplitude dependency of resonance frequency). Scanning electron microscopy (SEM) images and porosimetry results showed the formation of microcracks and increased micrometer porosity in a carbonated AAS binder caused by calcium aluminum silicate hydrate decalcification; the cracking was more severe in the SS-AS than in the SH-AS. The NRAS results revealed a close correspondence between the observed microscopic changes in the samples and measured macroscopic test parameters, indicating the potential of acoustic techniques for monitoring the advancement of carbonation fronts in AAS mortars.

Flipped Accumulative Non-Linear Single Impact Resonance Acoustic Spectroscopy (FANSIRAS): A novel feature extraction algorithm for global damage assessment

High amplitude non-linear acoustic methods have shown great potential for the identification of micro-damage in inhomogeneous materials such as concrete. Usually, these methods evaluate non-linearity parameters related to the hysteretic behaviour from the dependence of the shifts in both frequency and damping on the amplitude of the strain. A deep understanding of the reverberation phenomena has been obtained in order to introduce a novel signal processing approach called FANSIRAS (Flipped Accumulative Non-linear Single Impact Resonance Acoustic Spectroscopy). Traditional acoustic spectroscopy techniques, NIRAS (Non-linear Impact Resonance Acoustic Spectroscopy) and NSIRAS (Non-linear Single Impact Acoustic Spectroscopy), have been analyzed and compared with the brand new approach when providing quantitative information related to the degree of micro-cracking in thermal damaged concrete based materials. The new resonance-based algorithm demonstrates that the non-linear non-classical parameters can be determined through a single resonance frequency measurement, obtaining the expected sensitivity to internal damage. Its simplicity and robustness may be important in industrial applications.