Shear wave vertical

Splitting into two quasi shear waves If the transducer is coupling to the isotropic steel the incident shear wave may split into two independent quasi shear vertical wave-... 

Fig. 6. MR wave image of acoustic refraction. Shear waves generated in the upper part of an agar gel phantom (horizontal motion) propagate vertically in the stiff part of the phantom (/i 50 kPa cT 7.5 cm/s) and are refracted by the oblique lower part of soft gel (fi 15 kPa cT 4 cm/s). Note the marked reduction of wavelength in the softer medium. From Ref. 23, reprinted by permission of Wiley-Liss, Inc., a subsidiary of John Wiley Sons, Inc.

In the surface of a half space that is isotropic, the Rayleigh wave velocity is the same in all directions. If the surface is imagined to be in a horizontal plane, then the Rayleigh wave is composed of a shear wave component polarized in a vertical plane (SV) and a longitudinal wave component. Shear waves polarized horizontally (SH) can also exist, but they do not couple to the Rayleigh wave at all (nor, in the case of fluid loading, would they couple into waves in the fluid). 

Fig. 11.4. Velocities of bulk and surface waves in an (001) plane the angle of propagation in the plane is relative to a [100] direction, (a) Zirconia, anisotropy factor Aan = 0.36 (b) gallium arsenide, anisotropy factor Aan = 1.83 material constants taken from Table 11.3. Bulk polarizations L, longitudinal SV, shear vertical, polarized normal to the (001) plane SH, shear horizontal, polarized in the (001) plane. Surface modes R, Rayleigh, slower than any bulk wave in that propagation direction PS, pseudo-surface wave, faster than one polarization of bulk shear wave propagating in...

Figure 2.1 Pictorial representations of elastic waves in solids. Motions of groups of atoms ate depicted in these cross-sectional views of plane elastic waves propagating to the right. Vertical and horizontal displacements are exaggerated for clarity. Typical wave speeds, Vp, are shown below each sketch, (a) Bulk longitudinal (compressional) wave in unbounded solid, (b) Bulk transverse (shear) wave in unbounded solid, (c) Surface acoustic wave (SAW) in semi-infinite solid, where wave motion extends below the surface to a depth of about one wavelength, (d) Waves in thin solid plates.

Fig. 7. An example of upper-mantle splitting analysis for a Solomon Islands event recorded at the Canadian station ULM. The top traces show the radial and transverse component before and after the correction for SKS and SKKS splitting. The vertical bars marked A and F indicate the analysis window. It should be noted that after the correction the SKS and SKKS energy is minimized on the transverse component. The four lower-left panels show the isolated slow (continous line) and fast (dashed line) shear waves and the particle motion within the analysis window before and after the splitting correction. It should be noted also that the particle motion becomes linear after the correction. The lower right panel shows the confidence intervals for the sphtting parameters. The 95% confidence interval is the innermost circle around the asterisk at 50° and 0.96 s.

Vertically travelling shear waves (i.e. SKS phases) are then traced through the model using... 

Although this chapter is concerned with bulk acoustic wave (BAW) devices, some of the concepts apply to shear horizontal surface acoustic wave (SH-SAW) devices in a similar way [33,34]. When modeling SH-SAW devices, one usually decomposes the wave vector into a vertical and a lateral component. The vertical component obeys similar laws as the shear wave in a BAW resonator. This being said, we confine the discussion to BAW devices (also termed thickness-shear resonators) in the following. 

Dynamic response of loess slope with uniform and isotropie layers to vertically incident strong shear waves with different vibrating direetions... 

Changshougou loess slope in Baoji City is chosen as an analyzing example. A three-dimensional model of the slope and its physical and mechanical parameters are obtained according to the geotechnical condition of the slope and micro-tremor in situ testing result. The finite-difference software FLAC is adopted to simulate the dynamic response and failure patterns of the slope to the excitation of vertically incident shear waves with different vibrating directions and intensities. 

The bottom of the slope is excited by vertically incident shear waves. The acceleration time procedure of the shear wave is set up as a harmonic time procedure ... 

In order to simulate the dynamic responses of the slope excited by strong seismic waves, the harmonic vertically incident shear waves vibrating in X and Y directions are applied to the bottom of the model respectively. The harmonic shear wave lasts 32s so as to get a stable wave field in the slope body. The same peak acceleration a = = 0.11 g is set up... 

Sun, J.Z., Dong, S.Y, Li, G., et al. 2013. Dynamic response of loess slope with uniform and isotropic layers to vertically incident strong shear waves with different vibrating directions. Paper 49 in proceedings of the 9th Asian-IAEG, Beijing, 2013. 

The train loads applied to the FE model in this work are based on the X-2000 FIST consisting of one locomotive and four passenger cars, Kaynia et al. (2000) and Ekevid and Wiberg (2002). Only the vertical bogie loads are used for modeling this accounts only for the weight of the train and does not include any train dynamics. The supercritical, critical and subcritical train speeds pertain to FIST traveling at speeds above, at, or below the shear wave velocity of the soil. 

FIG. 5-14. Stroboscope photograph of a wave of shear strain double refraction in a 1% solution of sodium deoxyribonucleate at 2S°C, frequency 125 Hz. The driving plate is oscillated vertically shear waves propagated horizontally to the right produce patterns of strain double refraction. Each boundary between black and white provides the same information the inclination of the base lines is specified by the angle between the axes of the Babinet compensator and the analyzing Polaroid (from reference 117). ... 

Everything so far has treated the CSR as being caused by vertically propagating shear waves, a 1-D situation. This is obviously of uncertain relevance for soil-structure response situations such as quay walls. A reasonable view is that analysis where 2-D effects may be important will require finite element simulations with simple to advanced soil models. Discussion of these models is beyond the scope of this manual. However, the recommended site characterization presented in Section 8.6.6 does include the data needs for these types of analysis. 

If there is no access to a seismic CPT, shear wave velocity can also be measured by lowering geophones down a PVC cased borehole and measuring shear wave arrival times at regular depth intervals down the hole. The shear wave source can either be at the ground surface (vertical shear wave velocity profiling) or in an adjacent borehole (cross hole shear wave velocity measurement). 

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