Time and frequency domain evaluation of bender element systems

Tauta, Javier Fernando Camacho; Cascante, Giovanni; Fonseca, António Viana da; Santos, Jaime

doi:10.1680/geot.13.p.206

Cited by 40 publications

(20 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The BE technique has many advantages, which have been mentioned so far, but the interpretation of BE results can often be questionable [18,22,27]. A number of methods for the analysis of bender element results are commonly used in the time or frequency domain [17,28].…”

Section: Methods Of Interpretation Of Be Resultsmentioning

confidence: 99%

“…In certain experimental circumstances, such as during the measurements of G, the peak-to-peak method led to more scattered results, which were probably connected to the interpretation of the findings made by the authors. It must be always kept in mind, that even when using the same identification method, reading points differed with the laboratory [22]. The scatter in the S-S method was definitely smaller in comparison to another method.…”

Section: Discussionmentioning

confidence: 99%

“…Nevertheless, there are still some differences between the first arrival of the S-wave and the preferred input wave. Therefore, the BE technique still needs to be verified with respect to how reliable it is, when it comes to calculation of the arrival time [2,22].…”

Section: (1 )mentioning

confidence: 99%

See 2 more Smart Citations

Dynamic Characterization of Cohesive Material Based on Wave Velocity Measurements

et al. 2016

View full text Add to dashboard Cite

Abstract:The paper presents a description of the dynamic properties of cohesive material, namely silty clays, obtained by using one of the applied seismology methods, the bender elements technique. The authors' aim was to present the dynamics of a porous medium, in particular an extremely important passage of seismic waves that travel through the bulk of a medium. Nowadays, the application of the bender element (BE) technique to measure, e.g., small strain shear stiffness of soils in the laboratory is well recognized, since it allows for reliable and relatively economical shear wave velocity measurements during various laboratory experiments. However, the accurate estimation of arrival time during BE tests is in many cases unclear. Two different interpretation procedures (from the time domain) of BE tests in order to measure travel times of waves were examined. Those values were then used to calculate shear and compression wave velocities and elastic moduli. Results showed that the dynamic parameters obtained by the start-to-start method were always slightly larger (up to about 20%) than those obtained using the peak-to-peak one. It was found that the peak-to-peak method led to more scattered results in comparison to the start-to-start method. Moreover, the influence of the excitation frequency, the mean effective stress and the unloading process on the dynamic properties of the tested material was studied. In addition, the obtained results highlighted the importance of initial signal frequency and the necessity to choose an appropriate range of frequencies to measure the shear wave velocity in clayey soils.

show abstract

Section: Methods Of Interpretation Of Be Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Dynamic Characterization of Cohesive Material Based on Wave Velocity Measurements

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Bender elements have been widely utilized to measure V S at low strain levels, namely γ < 0.001 percentage [45]. The simple operation of these piezoceramic transducers, together with their small size, has stimulated their use in a big variety of geotechnical equipment since their first appearance [46].…”

Section: Methodsmentioning

confidence: 99%

“…However, BE testing is not yet a standard, due to the variability of its results in comparison with standard resonant column testing [45]. The reliability of BE technique is influenced by different factors, e.g., near-field effects [49], directivity [48], travel distance [50], boundary effects [51], sample geometry and size [52], cross-talking [53].…”

Section: Methodsmentioning

confidence: 99%

Application of Bender Elements Technique in Testing of Anthropogenic Soil—Recycled Concrete Aggregate and Its Mixture with Rubber Chips

et al. 2017

View full text Add to dashboard Cite

Featured Application: Recycled Concrete Aggregate can be a very good alternative material for natural aggregate. Using soil-rubber mixture as an engineering material may not only provide alternative means of reusing waste but also significantly change dynamic properties of soil.Abstract: This paper discusses the application of piezoceramic bender elements (BEs) for measurement of shear wave velocity in the time and frequency domain in a triaxial cell under different isotropic confinement. Different interpretation methods were used in the tests and their results were finally compared with each other. Two types of anthropogenic material were tested: pure Recycled Concrete Aggregate (RCA) and RCA-rubber chips mixtures (15% of rubber addition). Presented study is an attempt to describe dynamic properties, in terms of shear wave velocity (V S ), of the aforementioned anthropogenic material using the technique commonly applied for natural soil. Although some research is currently being carried out, in order to evaluate physical, chemical and mechanical properties of RCA and rubber-soil mixtures, still little is known of their dynamic properties. Hence, this work will provide the experimental results of shear wave velocity of RCA and its modified version. The results show that tires chips significantly decrease the V S values of modified RCA. They help to reduce the near field effect, but the received parameters are more incoherent. The V S values were found to be influenced by interpretation technique, mean effective stress and wave's propagation period. The maximum V S values were obtained mostly from the frequency domain method, although time domain analysis gives the results that are more coherent.

show abstract

Hydro‐micromechanical modeling of wave propagation in saturated granular crystals

Cheng

Luding

Rivas

et al. 2019

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

Summary Biot theory predicts wave velocities in a saturated granular medium using the pore geometry, viscosity, densities, and elastic moduli of the solid skeleton and pore fluid, neglecting the interaction between constituent particles and local flow, which becomes essential as the wavelength decreases. Here, a hydro‐micromechanical model, for direct numerical simulations of wave propagation in saturated granular media, is implemented by two‐way coupling the lattice Boltzmann method (LBM) and the discrete element method (DEM), which resolve the pore‐scale hydrodynamics and intergranular behavior, respectively. The coupling scheme is benchmarked with the terminal velocity of a single sphere settling in a fluid. In order to mimic a small amplitude pressure wave entering a saturated granular medium, an oscillating pressure boundary on the fluid is implemented and benchmarked with the one‐dimensional wave equation. The effects of input waveforms and frequencies on the dispersion relations in 3D saturated poroelastic media are investigated with granular face‐centered‐cubic crystals. Finally, the pressure and shear wave velocities predicted by the numerical model at various effective confining pressures are found to be in excellent agreement with Biot analytical solutions, including his prediction for slow compressional waves.

show abstract

Time and frequency domain evaluation of bender element systems

Cited by 40 publications

References 25 publications

Dynamic Characterization of Cohesive Material Based on Wave Velocity Measurements

Dynamic Characterization of Cohesive Material Based on Wave Velocity Measurements

Application of Bender Elements Technique in Testing of Anthropogenic Soil—Recycled Concrete Aggregate and Its Mixture with Rubber Chips

Hydro‐micromechanical modeling of wave propagation in saturated granular crystals

Contact Info

Product

Resources

About