Impact Resonance Test Research Articles

Mechanical Analysis through Non-Destructive Testing of Recycled Porous Friction Course Asphalt Mixture

This study assessed the mechanical performance of porous asphalt mixtures, specifically the porous friction course (PFC), incorporating 10% Reclaimed Asphalt Pavement (RAP) and rubberized asphalt. Three different methods were investigated to evaluate the stiffness of the mixtures: the resilience modulus (RM) test at a single temperature and loading frequency, the complex modulus |E*| test from compressive loading conducted at various temperatures and frequencies, and the impact resonance (IR) tests performed at three temperatures with five impacts applied to the mixture. The results demonstrated that the RAP-containing mixture exhibited a higher resilience modulus at all tested temperatures, indicating greater stiffness compared to the mixture without RAP. Additionally, the IR and |E*| tests revealed similar behavior between the two evaluated mixtures. These findings suggest that both quasi-static and vibrational tests are suitable for characterizing the stiffness of porous asphalt mixtures due to the similarity in the viscoelastic parameters of the two investigated mixtures. This study provides important insights into the practical and scientific application of recycled and modified materials in porous asphalt mixtures.

A comprehensive evaluation of damping, vibration, and dynamic modulus in reclaimed asphalt pavement: The role of rejuvenators, polymer, temperature, and aging

Reclaimed asphalt pavement (RAP) is increasingly essential in pavement engineering to enhance environmental sustainability. The use of rejuvenators and polymers has solved concerns about the dynamic performance of RAP; however, its damping and vibration properties still need to be investigated. Pavement vibrations pose a threat to public health, impeding sustainability. This research investigates RAP's damping performance, resonant frequency, and dynamic modulus using a non-destructive impact resonance (IR) test. Three RAP percentages (0 %, 50 %, and 100 %), three waste oil rejuvenators (paraffin oil, fatty acid, and base bitumen), and recycled high-density polyethylene (r-HDPE) were employed. Rejuvenators and r-HDPE were used separately and simultaneously at varying percentages. Evaluations were conducted under two conditions (long-term aged (LTA) and unaged) and two temperatures (25 °C and −12 °C). Findings reveal a performance hierarchy: under unaged conditions, rejuvenators exhibit superior efficacy, while simultaneous application of rejuvenator and recycled polymer optimally performs in prolonged aging scenarios. Statistical analyses underscore the pivotal role of rejuvenator quantity, irrespective of recycled polymer presence, aging, and temperature, as determinants in sculpting RAP's damping performance, resonant frequency, and dynamic modulus.

Static elastic modulus prediction at early ages using a modified resonant test for concrete cylinders using mems microphones

Concrete Young’s modulus is seldom verified on-site due to the time-consuming and costly nature of current testing standards. This article proposes a new, quick and affordable testing methodology to estimate the ultimate static elastic modulus of normal strength concrete cylinders on-site at early ages using a smartphone. Impact-resonance tests were performed on several concrete cylinders from different mixtures at different ages, using an accelerometer and a smartphone microphone to measure the cylinders' flexural and longitudinal resonant frequencies. Measurements from both sensors were compared to show the validity of estimating the dynamic elastic modulus using acoustic signals from the cylinders recorded with a smartphone's built-in microphone. The cylinders' static and dynamic elastic moduli were determined, and the change in elastic modulus over time as the cylinders aged was also examined. This study shows the advantages of microphones over accelerometers, being less susceptible to measurement errors and proposes a filter algorithm to extract the resonant frequencies from environmental noise. A forecasting methodology to estimate static elastic modulus based on early dynamic impact-resonant tests can help engineers make early decisions on their supplied concrete on-site.

Determination of the stiffness of ecological asphalt mixtures with non-destructive impact resonance tests

The objective of this study is to characterize the linear viscoelastic behavior of ecological asphalt mixtures with non-destructive impact resonance testing. Two specimens of each of the four investigated mixtures were produced and tested in laboratory: a reference mixture (REFMIX), a mixture containing a modified binder with 30% of Kraft lignin in mass of total binder (LIGNIN), a mixture with 20% of reclaimed asphalt pavement (RAP) in mass of total aggregates (RAP20), and a mixture with 50% of RAP (RAP50). The specimens were tested at five temperatures (-20 °C, 0 °C, 10 °C, 20 °C, and 30 °C) with an impact resonance equipment to obtain experimental Frequency Response Functions (FRF’s). Subsequently, a back-calculation procedure was used to determine two linear viscoelastic properties (absolute value and phase angle of the complex modulus) from FRF’s measurements using finite element method (FEM) simulations. The results indicated a good repeatability of the test, with results from all specimens presenting the same trend, a decrease of the modulus and an increase of the phase angle with increasing temperature. Results also showed that the modified mixtures are stiffer than the reference mixture at each temperature. Kraft lignin has the greatest influence in increasing the stiffness in comparison with the reference mixture, followed by the addition of 50% and 20% of RAP. It was concluded that the addition of ecological materials, such as lignin and RAP, directly affects the viscoelastic behavior of bituminous materials, which can be beneficial for many applications.

Evaluating Moisture Damage Using Impact Resonance Test

Abstract Moisture damage in asphalt mixtures has been a major cause for premature failure of asphalt pavements for decades. Although a lot of research has been done and many test methods have been developed to evaluate moisture damage in asphalt mixtures, not much research has been done on the use of nondestructive testing techniques to evaluate moisture damage in asphalt mixtures. The impact resonance (IR) test is a nondestructive test that is used to determine material properties like dynamic elastic modulus. The IR test on asphalt mixtures is done on a thin-disk specimen (150-mm diameter and 25-mm thickness). In this study, the IR test was used to assess moisture damage in asphalt mixtures by determining the resonant frequency of asphalt mixture samples in the unconditioned and moisture conditioned state. The relative reduction (ER) in dynamic elastic modulus was calculated as the ratio of the resonant frequency of conditioned and unconditioned specimens from the IR test, which was used to evaluate moisture damage. Moisture sensitivity of the asphalt mixtures was also determined by the tensile strength ratio (TSR) test. Two different moisture conditioning procedures were used for both the IR test and TSR test—modified AASHTO T 283 (Standard Method of Test for Resistance of Compacted Asphalt Mixtures to Moisture-Induced Damage) and Moisture Induced Stress Tester (MIST) conditioning. Six different mixtures from three different aggregate sources were used in this study. A good correlation was observed between TSR values from the TSR test using both conditioning procedures and the ER values from the IR test using both conditioning procedures for the asphalt mixtures used in this study. This study shows that the IR test can be used to evaluate moisture damage in asphalt mixtures. This study also explored the effects of various parameters such as support condition, impact source, and impact location on the resonant frequency from the IR test.

Seismic Isolation Effect of Non-Water Reacted Two-Component Polymeric Material Coating on Tunnels

An isolation layer is one of the countermeasures to promote the anti-seismic performance of tunnels. A newly invented polymeric material, non-water reacted two-component polymeric material (NRTCPM), is superior in impermeability and construction efficiency. In this study, covering a tunnel with NRTCPM coating to mitigate the damage caused by an earthquake is discussed, and an Impact Resonance Test (IRT) is firstly used to obtain the damping ratios and dynamic elastic modulus of NRTCPM. By using infinite element boundary, eight dynamic numerical modelsare made to study the isolation effects based on different density, Poisson’s ratio, dynamic elastic modulus and thickness of isolation layer values. Three different conditions are explored in this paper, namely (1) no NRTCPM layer coating around tunnel; (2) different densities, Poisson’s ratios and dynamic elastic moduli of a polymeric layer; and (3) various thicknesses of polymeric isolation layers around the lining. Tensile and compressive stresses are compared under these different conditions. The results show that retrofitting tunnel lining with this material has a good effect on seismic isolation. An optimum density and thickness of the NRTCPM layer is suggested considering cost and strength.

Non-Water Reacted Two-Component Polymer Based on Impact Resonant Test in Oceanic Traffic Engineering

Non-water reacted two-component polymer (NRTCP), a newly invented polymeric material, has been widely used in various engineering projects because of its advantages, such as impermeability, time saving, and labor saving. Impact resonance test (IRT) is a type of nondestructive test method. This method has been applied to obtain the dynamic elastic modulus of Portland cement concrete and pavement asphalt traditionally, but it has not been used to test NRTCP. In this study, the damping ratio and elastic modulus of NRTCP are obtained through IRT under different circumstances, such as various liquid depths, salt contents, immersion times and densities. Results show that all changes remarkably affect the damping ratio and dynamic elastic modulus of NRTCP. These findings provide a reference for NRTCP usage in oceanic traffic engineering.

Evaluation of Nondestructiveness of Resonant Column Testing for Characterization of Asphalt Concrete Properties

Abstract The resonant column (RC) test has been used as a nondestructive test (NDT) to study dynamic properties of soils for the past few decades. With some modifications, this test can also be employed to characterize properties of asphalt concrete, especially because these properties are strongly dependent on the loading frequency. A conventional RC apparatus was retrofitted to characterize asphalt concrete properties at a range of temperatures from 10°C to 45°C. The RC test is believed to be nondestructive for most soils; however, this must be verified in case of testing asphalt concrete, especially at elevated temperatures. For this purpose, the impact resonance (IR) test, as a purely NDT tool, was used to check the integrity of asphalt concrete specimens before and after RC testing. The modulus values measured before and after RC tests, at each of the testing temperatures, were compared to evaluate the nondestructiveness of RC testing. Strain levels were also monitored to ensure that the material remained within the linear elastic range through the tests. The results show that the specimens exhibited the same modulus before and after RC testing over the full range of temperature and frequency sweep tests.

Estimation of the Dynamic Moduli of Viscoelastic Asphalt Mixtures Using the Extended Kalman Filter Algorithm

Here, we develop a model predicting the dynamic moduli of hot‐mix asphalt/concrete using the extended Kalman filter (EKF) algorithm and draw frequency‐domain master curves. Discrete dynamic moduli were obtained via impact resonance tests (IRTs) on linear viscoelastic (LVE) asphalt at 20, 30, 35, 40, and 50°C. Typically, viscoelastic characteristics have been used to derive asphalt dynamic moduli; compressive frequency sweep tests at different frequencies (Hz) and temperatures are employed to this end. We compared IRT‐derived viscoelastic master curves obtained via compressive frequency sweep testing to those derived using the EKF algorithm, which employs a nonlinear sigmoidal curve and a Taylor series to explore the viscoelastic function. The model reduced errors at both low and high frequencies by correcting the coefficients of the master curve. Furthermore, the predictive model effectively estimated dynamic moduli at various frequencies, and also root‐mean‐square errors (RMSEs) which, together with the mean percentage errors (MPEs), were used to compare predictions.

Validation of Model Order Assumption and Noise Reduction Method for the Impact Resonance Testing of Asphalt Concrete

The impact resonance test is a free vibration-based nondestructive test method that has been increasingly used in evaluation and characterization of asphalt concrete for the past two decades. The rheological modeling of the impact resonance test is conceptualized by a linear viscous damping mechanism having single degree of freedom whose equation of the motion is assumed to be second order. In this study, the second order equation of motion assumption in the modeling of the impact resonance test response was evaluated for asphalt concrete testing. A set of asphalt concrete specimens was tested with the impact resonance test, and the obtained signals at a range of temperatures were evaluated by means of the Hankel matrix method. The results showed that the assumption is violated for asphalt concrete testing especially at high temperatures, mainly due to the presence of noise in the obtained response. However, the Hankel method was employed to filter out the noise. It was seen that the assumption could be employed for asphalt concrete at a range of temperatures including high temperatures, provided that the filtering is performed on the obtained signal. The results also showed that the employed filtering procedure produced improvements for the impact resonance test material dependent responses, resonant frequency and especially damping ratio calculations.

The advantages of using impact resonance test in dynamic modulus master curve construction through the abbreviated test protocol

Asphalt concrete behavior is heavily dependent on temperature and loading rate. Hence, the material is typically tested at a range of temperatures and loading frequencies to capture its properties. Results are then used to develop a master curve exhibiting material behavior at the full spectrum of loading frequencies. An abbreviated testing protocol, under AASHTO PP 61-13, proposes a practical approach for development of this master curve. In this practice, the low temperature asymptote of the master curve is dominated by the limiting maximum modulus estimated through the Hirsch model. In this study, the dynamic modulus (DM) testing coupled with impact resonance (IR) test was used to evaluate the effect of this limiting maximum modulus on construction of the asphalt concrete master curve. Three different asphalt mixtures prepared with the same gradation and binder content, but different grades of stiffness were tested. The DM testing was performed at multiple temperatures and loading frequencies. The IR tests were conducted on the same specimens at the same temperatures. Two sigmoid functions (MEPDG and Richards models), and three shift factors (Arrhenius, Williams–Landel–Ferry, and polynomial) were utilized in the analysis. Richards sigmoid function coupled with polynomial shift factor provided the best fitting accuracy to the measured data. It was observed that the limiting maximum modulus obtained from experimental data was underpredicted by that obtained from the Hirsch model. The results indicated potential benefits of the IR test as a complementary testing tool to the abbreviated DM testing protocol to reliably characterize asphalt concrete.

Damping and mechanical properties of composite composed of polyurethane matrix and preplaced aggregates

This paper presents an experimental study of the damping and mechanical properties of a new composite produced by a two-stage casting process. Five mixtures according to the materials and manufacturing process were prepared. A series of experiments, including density, impact resonance, compressive strength, flexural strength, and uniaxial tension tests, were performed in order to characterize the damping and mechanical properties of the composite. The test results showed that the composite, which is composed of preplaced aggregate and polyurethane matrix, and produced by manufacturing process proposed in this study, showed significantly improved damping performance as well as better tensile behavior.

Determination of Dynamic Modulus Values of Asphalt Mixtures Using Impact Resonance Testing of Thin Disk Specimens

Abstract The impact resonance (IR) test is a nondestructive test method that is used to characterize the linear viscoelastic behavior of asphalt concrete. This method is preferred over other methods because the setup of the IR test is simpler, more efficient, and less expensive than standard axial compression dynamic modulus (|E*|) tests. Researchers originally developed the IR test method for cylindrical specimens of asphalt mixtures and concluded that this method can serve as an alternative to |E*| tests. However, the geometry (100 mm in diameter by 150 mm in height) of the cylindrical specimens used in these tests prohibits the use of IR tests for field cores. Therefore, researchers began to consider thin disk-shaped specimens for IR testing because thinner geometry of such specimens better represents slices of field cores. In this study, a test procedure was developed to evaluate the use of thin disk-shaped specimens for IR tests in order to determine the |E*| values of asphalt mixtures. The IR test protocol was optimized using 2 IR test methods (referred to as Case 1 and Case 2 in this work) under various test conditions to ensure the highest possible quality of the data. Optimal test methods were proposed based on the repeatability and variability of the resonant frequency and phase angle data and the ability of the different test conditions to provide data that best match the |E*| values obtained from standard axial compression |E*| tests. The results demonstrate that the |E*| values of thin disk-shaped specimens determined from the optimized IR tests are similar to the |E*| values of long cylindrical specimens determined from conventional |E*| AASHTO T 342-11 tests and IR tests.

Individual temperature based models for nondestructive evaluation of complex moduli in asphalt concrete

The rheological properties of bituminous materials play important roles in the selection of paving materials, and analysis and design of asphalt pavements. The series of models developed in this study are composed of five formulations for the creation of the dynamic modulus mastercurve at a wide range of testing temperatures. The predictability of these models is assessed by comparing the predicted dynamic modulus mastercurves of different mixtures with measured ones from a nondestructive impact resonance (IR) test. This assessment shows that the predictions match the dynamic modulus values measured from different techniques with a good level of accuracy.

Impact non-linear reverberation spectroscopy applied to non-destructive testing of building materials

The development of non-destructive testing techniques to detect early micro damage in concrete and other building materials is important for efficient maintenance and management of existing infrastructure. Nonlinear acoustic methods have shown potential for the identification of early damage in brittle materials such as concrete. Commonly, these methods evaluate relative nonlinearity parameters from multiple resonance tests at different amplitudes. We demonstrate a recently developed alternative method, Impact Nonlinear Reverberation Spectroscopy (INRS), where quantitative nonlinearity parameters are evaluated from a single impact resonance test. The recorded reverberation of the measured signal is matched to a synthetic nonlinear damped signal. The proposed model allows instantaneous true physical amplitude, frequency, and damping of each mode to be characterized as a function of time, allowing for quantitative information of the nonlinear parameters. The hysteretic material nonlinearity can be quantitatively characterized over a notably wider dynamic range compared to conventional methods. Two examples from the application to concrete and stabilized soil are presented. In addition quantitative values of the hysteretic nonlinear parameter from stabilized soil samples are compared with the measured ultimate compressive strength of each sample.

Investigating the effect of rejuvenators on low-temperature properties of recycled asphalt using impact resonance test

ABSTRACTUse of recycled asphalt pavement (RAP) in highway construction is highly promoted due to recent awareness in sustainable construction practices. The concerns with material brittleness in utilising higher content of RAP are alleviated through addition of rejuvenators to some extent. Inclusion of rejuvenator to the aged binder improves its flexibility and lessens its cracking potential. A study was undertaken to investigate the effectiveness of the impact resonance (IR) testing in determining low-temperature binder properties through mixture testing. To this effect, the presented study consisted of two stages. In stage I, the IR test was conducted on mixes made with different low-temperature grade binders. Stage II consisted of testing pure RAP mixes treated with a rejuvenating agent at different levels using the IR as well as testing blends of recovered RAP binder and rejuvenator and virgin binder using bending beam rheometer (BBR). The IR test was performed at a range of temperatures between and . The results indicate that the IR test can successfully capture the low-temperature properties of binders in virgin mixes as well as RAP mixes incorporating rejuvenator. A very high linear correlation was observed between stiffness from IR testing of the RAP mix and stiffness from BBR testing of the blend of recovered binder and virgin binder and rejuvenator. A good correlation was also observed between phase angle of RAP mixes obtained from IR with the m-value, a relaxation index, from BBR at a range of temperatures for a given rejuvenator content. The results clearly demonstrate the potential of IR to be used for grading and optimisation for the asphalt binder of RAP and rejuvenator content in lieu of the binder recovery method.

The potential of using impact resonance test method evaluating the anti-freeze-thaw performance of asphalt mixture

Asphalt pavements around the world are generally subjected to water from different sources which may eventually make them susceptible to moisture damage. However, most of tests used to investigate the moisture damage are destructive, which will consume a lot of materials, energy and time to prepare the specimen. There is a need to find a simple and quick non-destructive test to evaluate the moisture damage of asphalt mixture. In this paper, the impact renounce test is employed and the possibility on evaluating the anti-freeze-thaw performance of asphalt mixtures is discussed. It is found that the dynamic modulus obtained by impact resonance test and repeated loading test method correlate very well, and using impact resonance test method we can well evaluate the anti-freeze-thaw performance of different asphalt mixtures. It is also found that the properties of neat asphalt have significant effect on the anti-moisture damage properties, and rubber asphalt mixture has better anti-freeze-thaw performance than neat asphalt mixture; the particle size of rubber powder also shows an impact on the resistance to freeze-thaw performance of asphalt mixture. Different specimen thicknesses and different tapping positions have significant effect on the repeatability of test results; it is recommended that using 4cm thickness specimen and impacting on the edge of specimen to evaluate the degradation of asphalt mixture anti-freeze-thaw performance.

The Effect of Aspect Ratio on the Frequency Response of Asphalt Concrete in Impact Resonance Testing

Abstract A comprehensive study was conducted to investigate the influence of aspect ratio (height/diameter) of laboratory specimens on the frequency response of asphalt concrete when tested with impact resonance (IR). Testing was conducted over a range of air voids and temperatures. The IR test, performed in longitudinal mode over 100 cylindrical asphalt concrete specimens, demonstrated that the test is repeatable and reproducible. It was observed that the test response was greatly dependent on the specimen length regardless of the aspect ratio, but the dependency was not noted for specimens with the same diameter of larger aspect ratios. Specimens with the same aspect ratio but different size delivered different resonant frequencies. The test results indicated that the frequency response increased as the aspect ratio increased approximately up to 0.7, and then it decreased with a nonlinear trend as the aspect ratio increased beyond 0.7, indicating the tendency of the frequency response reaching a plateau as the aspect ratio increased. It was inferred from test results that there was a threshold aspect ratio at which the fundamental longitudinal frequency mode was not the dominant frequency mode. Velocity calculations from measured resonant frequencies indicated that the true material properties could be attained at an aspect ratio of as low as 1. Based on the results of this study, testing specimens with a diameter of 150 mm and a height of 170 mm commonly used for producing dynamic modulus test specimens, provided proper size and aspect ratio for testing with IR.

Evaluating Impact Resonance Testing As a Tool for Predicting Hydraulic Conductivity and Strength Changes in Cement-Stabilized Soils

In this paper the impact resonance (IR) test method is used as a nondestructive tool to examine the curing progression, freeze/thaw (f/t) resistance, and healing potential of cement-stabilized soils. Resonant frequency (RF) measurements on specimens moist cured for up to 241 days indicate that the main portion of the hydration process is completed after about 60 days. Results of RF measurements on immature (i.e., cured for 16 days) and mature (i.e., cured for over 110 days) specimens exposed to 12 cycles of f/t indicate that the initial f/t exposure had a significant effect on the degradation of the structure. After the initial f/t cycle, some specimens exhibited continued reductions in RF values to as low as 10% of the initial measurements, while several specimens showed signs of recovery leading to minor increases in the RF values. Changes in RF values are compared with the hydraulic conductivity changes measured on the same specimens reported in a previous publication by the authors. Based on the results, a prescreening scheme is proposed that can significantly reduce the time required for f/t studies of cement-stabilized soils. Also, RF measurements after 120 days of a post-exposure healing period show a significant potential for recovery in RF values for f/t exposed specimens. However, the recoveries in RF values are not proportional to the hydraulic conductivity recovery of the specimens.

Measurement of the moisture content of a waste paper bale based on the impact resonance test

The quality of a waste paper bale depends heavily on its moisture content. The higher the moisture content, the lower the quality as a recycled resource. Therefore, accurate measurement of the moisture content of a waste paper bale is a pressing concern in the paper recycling industry. In this paper, a theoretical model for a waste paper bale, an exotic and complex medium, is developed, in which the acoustic properties of the bale are assumed to be functions of the moisture content. The model is validated through a series of impact resonance tests, which show a strong correlation between the moisture content, resonance frequencies, and the associated quality factors.