Determination of the internal structure of alpine talus deposits using different geophysical methods (Lechtaler Alps, Austria)

Geomorphology ◽  
2006 ◽  
Vol 80 (1-2) ◽  
pp. 45-58 ◽  
Author(s):  
Oliver Sass
Author(s):  
Matylda Tankiewicz

Abstract In the paper the results of laboratory investigations of structure of layered soil are presented. They focus on varved clay that is a soil composed of two alternately arranged varves with different texture and mechanical properties. An effect of such structure is an anisotropy of the material. Due to varying conditions during its formation process the soil exhibits some irregularities in composition and structure. Due to that modelling of mechanical behavior, like strength, may not provide satisfactory results. Main purpose of the examinations is an investigation of internal structure of layered soil – varved clay – in relation to its strength anisotropy and evaluation of the suitability of the use of two different techniques to assess the soil structure. Investigated material have been taken from area near city of Bełchatów in central Poland. The examinations included investigation of particle size distribution of soil and its components, identification of lamination with use of scanning electron microscope (SEM) and computed microtomography technique (μCT). First, the texture of each varve and varved clay as a composite have been estimated. Next, the investigation of surface perpendicular to the lamination have been carried out with SEM. Pictures of varves with different magnifications are presented. Also the varves arrangement and details of layers contact area are shown. Finally, investigation of internal structure of the soil have been performed by using microtomograph. The outcome is a series of radiographic images and reconstructed 3D model of tested soil. Presented results show complexity of the structure of varved clay that affect the mechanical behavior. Determination of the structure with use of presented techniques may be helpful in examination of strength properties and proper modeling of such soil.


2016 ◽  
pp. 25-29
Author(s):  
G. E. Stroyanetskaya

The problems of collectors at the stage of calculating the reserves in operating incline directional wells, penetrated on clay, polymer-clay solution, polymer washing liquid with hydrochloric-calcium foundation were considered. The electrical resistivity of the solution and the washing liquid from 0.1 to 1 O·mm. According to geophysical methods, establishing of the criteria for the allocation of the collectors requires coring. The main methods for the isolation of collectors are lateral, microlaterolog survey and caliper measurement. The techniques of the gas-saturated collectors porosity coefficient determination were considered.


Author(s):  
Yurii Nikolaevich Orlov

The statistical properties of letters frequencies in European literature texts are investigated. The determination of logarithmic dependence of letters sequence for one-languge and two-language texts are examined. The pare of languages are suggested for Voynich Manuscript. The internal structure of Manuscript is considered. The spectral portraits of two-letters distribution are constructed.


2006 ◽  
Vol 61 (3) ◽  
pp. 201-208 ◽  
Author(s):  
R. Bell ◽  
J.-E. Kruse ◽  
A. Garcia ◽  
T. Glade ◽  
A. Hördt

Abstract. Landslides occur frequently all over the world, causing at times considerable economic damage, injuries and even death. In order to improve hazard assessment, common landslide types of a given region need to be investigated in detail. While traditional techniques of subsurface investigation are expensive and only provide point information, geophysical methods are suitable tools for gathering 2D and 3D information on the subsurface quickly, reliably and cost-effectively. In this study, the suitability and limitations of 2D resistivity for the determination of landslide extent, structure and soil moisture conditions are presented. For this purpose, two identical profiles were taken during a two-month period. Significant differences in electrical resistivity (>1000 Ωm) due to varying soil moisture conditions were observed. Using various inversion parameters, it was possible to model two distinct subsurface images. Regrettably, the sliding plane could not be detected reliably, possibly due to the homogeniety of the landslide material and underlying bedrock.


Geosciences ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 406
Author(s):  
Mario Bačić ◽  
Lovorka Librić ◽  
Danijela Jurić Kaćunić ◽  
Meho Saša Kovačević

Having in mind uncertainties linked with the nature of rock masses, it is a challenge for geotechnical engineers to characterize them in a credible manner, especially if the rock mass in question is a notoriously complex karst with its distinctive features such as voids and discontinuities. A large range of geophysical methods are useful tools in the characterization efforts and their utilization in karst environments nowadays is a non-negotiable requirement, even though near-surface scattering significantly affects the acquired data. This paper demonstrates the versatile applications of seismic geophysical methods for geotechnical engineering in karst, from mapping of near-surface karstic features to the application of elastic wave velocities in determination of small to large strain stiffness of karst. The highlighted practical examples offer a step forward from the traditional interpretation of seismic surveys, making them a prosperous tool in geotechnical engineering investigation works, design and quality control campaign.


2015 ◽  
Vol 760 ◽  
pp. 141-146 ◽  
Author(s):  
Jan Lipina ◽  
Václav Krys ◽  
Jiří Marek

Recently, the Rapid Prototyping technology (RP hereafter) has been increasingly used for a final product, which requires detailed knowledge of designing parts made by the RP technology. In order to apply parts made by the RP technology in robotics, and design in general, in a wider range, one of the most important material parameters is their bend strength. The paper describes an experimental determination of bend strength in parts printed on a 3D printer. The parts were made of polycarbonate. The tests were carried out in parts with various types of internal structure. The achieved results can be implemented when designing parts made by 3D printing provided that professional printers are used.


2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Amin Amini ◽  
Hamidreza Ramazi

AbstractThis paper is devoted to the application of the Combined Resistivity Sounding and Profiling electrode configuration (CRSP) to detect underground cavities. Electrical resistivity surveying is among the most favorite geophysical methods due to its nondestructive and economical properties in a wide range of geosciences. Several types of the electrode arrays are applied to detect different certain objectives. In one hand, the electrode array plays an important role in determination of output resolution and depth of investigations in all resistivity surveys. On the other hand, they have their own merits and demerits in terms of depth of investigations, signal strength, and sensitivity to resistivity variations. In this article several synthetic models, simulating different conditions of cavity occurrence, were used to examine the responses of some conventional electrode arrays and also CRSP array. The results showed that CRSP electrode configuration can detect the desired objectives with a higher resolution rather than some other types of arrays. Also a field case study was discussed in which electrical resistivity approach was conducted in Abshenasan expressway (Tehran, Iran) U-turn bridge site for detecting potential cavities and/or filling loose materials. The results led to detect an aqueduct tunnel passing beneath the study area.


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