Full Waveform Acoustic Logging for Slope Weak Layer Evaluation

2012 ◽  
Vol 170-173 ◽  
pp. 159-163
Author(s):  
Zhong Qiu Xie ◽  
Jin Zhao Fan ◽  
Hong Bin Xiao Xiao ◽  
Yu Chi Zhang
Keyword(s):  
Rock Mass ◽  
Acoustic Wave ◽  
Rock Deformation ◽  
Stoneley Wave ◽  
Propagation Characteristics ◽  
Full Waveform ◽  
Filling Ability ◽  
Unstable Failure ◽  
Shaft Lining ◽  
The Relationship

Rock deformation and unstable failure of slope is controlled by weak structural plane whose identification and evaluation is greatly influenced by deformation failure prediction of slope and design treatment. Based on the propagation characteristics of acoustic wave in shaft lining strata, attenuation of stoneley wave and inherent attenuation of strata are analyzed and permeability relationship among shaft lining strata is researched. The relationship between reflected stoneley-wave intensity and the width and filling ability of strata crack is studied. By application example of landslide investigation, attribute parameters and characteristics of acoustic wave are discussed. Strata division, the practicability and accuracy of recognition for fracture and holes evaluation and mechanic characteristics of rock mass also are studied.

Numerical Simulation of Acoustic Wave Propagation in Cylindrical Fluid-Saturated Poroelastic Shell Immersed in Fluids

2011 ◽  
Vol 105-107 ◽  
pp. 127-131
Author(s):  
Wen Yang Gao ◽  
Qian Wu ◽  
Zhi Wen Cui ◽  
Kei Xie Wang ◽  
He Feng Dong
Keyword(s):  
Numerical Simulation ◽  
Cylindrical Shell ◽  
Wave Propagation ◽  
Acoustic Wave ◽  
Acoustic Pressure ◽  
Fluid Pressure ◽  
Longitudinal Mode ◽  
Stoneley Wave ◽  
Acoustic Wave Propagation ◽  
Full Waveform

Acoustic wave propagation in fluid-saturated porous cylindrical shell is investigated in this paper by using the Biot’s theory. The Expressions for acoustic pressure and radical displacement in and out fluid, the expressions for components of solid and filtration displacement and pore fluid pressure and stress tensor are given. The numerical simulation is operated on acoustic field in fluid of poroelastic cylindrical shell, and the full-waveform is obtained by Fourier transform, and acoustic pressure field in frequency-wavenumber domain is analyzed, as well as the influence of inner and outer radii on wave amplitude is discussed. It shows that if the thickness of shell remains constant, the amplitude of longitudinal mode increases and that of Stoneley wave decreases when inner and outer radii increasing. In the fast formation the influence of inner and outer radii on the amplitude of longitudinal mode is notable. In the slow formation the amplitude of Stoneley wave will decrease with inner and outer radii increasing.

scholarly journals Evaluation of Shear Horizontal Surface Acoustic Wave Biosensors Using “Layer Parameter” Obtained from Sensor Responses during Immunoreaction

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4924
Author(s):  
Koji Kano ◽  
Hiromi Yatsuda ◽  
Jun Kondoh
Keyword(s):  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Horizontal Surface ◽  
Propagation Characteristics ◽  
Viscosity Change ◽  
Layer Parameter ◽  
Antibody Reaction ◽  
Antigen Antibody ◽  
Shear Horizontal ◽  
Molecular Dimensions

Shear horizontal surface acoustic wave (SH-SAW) biosensors measure the reaction of capture antibodies immobilized on the sensing surface to capture test molecules (antigens) by using the change in SH-SAW propagation characteristics. SH-SAW displacement exists not only on the SH-SAW propagating surface, but also partially penetrates the specimen liquid to a certain depth, which is determined by the liquid properties of the specimen and the operating frequency of the SH-SAW. This phenomenon is called viscosity penetration. In previous studies, the effect of viscosity penetration was not considered in the measurement of SH-SAW biosensors, and the mass or viscosity change caused by the specific binding of capture antibodies to the target antigen was mainly used for the measurement. However, by considering the effect of viscosity penetration, it was found that the antigen–antibody reaction could be measured and the detection characteristics of the biosensor could be improved. Therefore, this study aims to evaluate the detection properties of SH-SAW biosensors in the surface height direction by investigating the relationship between molecular dimensions and SH-SAW propagation characteristics, which are pseudo-changed by varying the diameter of gold nanoparticles. For the evaluation, we introduced a layer parameter defined by the ratio of the SH-SAW amplitude change to the SH-SAW velocity change caused by the antigen–antibody reaction. We found a correlation between the layer parameter and pseudo-varied molecular dimensions. The results suggest that SH-SAW does not only measure the mass and viscosity but can also measure the size of the molecule to be detected. This shows that SH-SAW biosensors can be used for advanced functionality.

scholarly journals Development of a mathematical model for calculating the process of crushing hard rocks by explosions of cylindrical charges of explosives

2020 ◽  
Vol 5 ◽  
pp. 30-32
Author(s):  
Norov Yunus Dzhumaevich ◽  
Mehmonov Maksud Rabbonokul ugli
Keyword(s):  
Mathematical Model ◽  
Rock Mass ◽  
Mechanism Of Action ◽  
Mathematical Description ◽  
Granulometric Composition ◽  
Rock Fragmentation ◽  
Hard Rocks ◽  
Definition Of ◽  
The Relationship

The article presents a developed mathematical model for calculating the granulometric composition of the blasted rock mass based on the mechanism of action of an explosion in rocks, a mathematical description of the determination of natural units (blocks) in the rock mass, the relationship between the degree of rock fragmentation and the size of the units and the definition of sections of the controlled pressure zone.

scholarly journals Characteristics of Global Oceanic Rossby Wave and Mesoscale Eddies Propagation from Multiple Datasets Analysis

2016 ◽  
Author(s):  
Yunfan Zhang ◽  
Fenglin Tian ◽  
Ge Chen
Keyword(s):  
Rossby Wave ◽  
Phase Speed ◽  
Mesoscale Eddies ◽  
Propagation Speed ◽  
Ocean Current ◽  
Propagation Characteristics ◽  
The North ◽  
Multiple Datasets ◽  
Salinity Data ◽  
The Relationship

Abstract. In this paper we present a research of propagation characteristics of global Rossby wave and mesoscale eddies, and we preliminarily discussing the relationship between them from multiple datasets analysis. By filtering the MSLA-H data and by means of optimized SSH method we have extracted signals of the Rossby wave, and estimated the propagation speed (zonal phase speed) of the Rossby wave and eddies. Validation for the identification of the Rossby wave also has been completed with the Argo temperature and salinity data. The prime focus covers: propagation speed comparison between the Rossby wave and the eddies, propagation characteristics in different regions. Overlaying the signals of the Rossby wave with the signatures of the eddies indicates that the Rossby wave and the eddies propagates together (westward only) in the mid-latitude, but differences appear with increasing of latitude, especially in some areas affected by ocean current, for instance, the West Wind Drift(WWD) and the North Atlantic Drift(NAD). Actually we have found that the currents led the eddies, and the Rossby wave might play an accelerative or moderative role in the eddies propagation, as a result of the velocities of the eddies and the currents were matched well, but comparison between the Rossby wave and the eddies revealed disparity. The findings are useful for understanding the relationship between the Rossby wave and mesoscale eddies.

scholarly journals Mechanism of Fracturing in Shaft Lining Caused by High-Pressure Pore Water in Stable Rock Strata

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Jihuan Han ◽  
Jiuqun Zou ◽  
Weihao Yang ◽  
Chenchen Hu
Keyword(s):  
High Pressure ◽  
Rock Mass ◽  
Pore Water ◽  
Expansion Coefficient ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Surrounding Rock ◽  
Shaft Lining ◽  
Rock Strata ◽  
Expansion Effect

With the increase in shaft depth, the problem of cracks and leakage in single-layer concrete lining in porous water-rich stable rock strata has become increasingly clear, in which case the mechanism of fracturing in shaft lining remains unclear. Considering that the increase in pore water pressure can cause rock mass expansion, this paper presents the concept of hydraulic expansion coefficient. First, a cubic model containing spherical pores is established for studying hydraulic expansion, and the ANSYS numerical simulation, a finite element numerical method, was used for calculating the volume change of the model under the pore water pressure. By means of the multivariate nonlinear regression method, the regression equation of the hydraulic expansion coefficient is obtained. Second, based on the hydraulic expansion effect on the rock mass, an interaction model of pore water pressure–porous rock–shaft lining is established and further solved. Consequently, the mechanism of fracturing in shaft lining caused by high-pressure pore water is revealed. The results show that the hydraulic expansion effect on the surrounding rock increases with its porosity and decreases with its elastic modulus and Poisson’s ratio; the surrounding rock expansion caused by the change in pore water pressure can result in the outer edge of the lining peeling off from the surrounding rock and tensile fracturing at the inner edge. Therefore, the results have a considerable guiding significance for designing shaft lining through porous water-rich rock strata.

Propagation Characteristics of Blast-Induced Vibration in Parallel Jointed Rock Mass

2019 ◽  
Vol 19 (5) ◽  
pp. 04019025 ◽  
Author(s):  
Yonggang Gou ◽  
Xiuzhi Shi ◽  
Xianyang Qiu ◽  
Jian Zhou ◽  
Hui Chen ◽  
...  
Keyword(s):  
Rock Mass ◽  
Jointed Rock ◽  
Jointed Rock Mass ◽  
Propagation Characteristics
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