scholarly journals Principles and Developments in Soil Grouting: a Historical Review

2021 ◽  
Vol 18 ◽  
pp. 175-191
Author(s):  
Dimitrios Christodoulou ◽  
Philotheos Lokkas ◽  
Ioannis Markou ◽  
Alexandros Droudakis ◽  
Ioannis Chouliaras ◽  
...  
Keyword(s):  
Historical Review ◽  
High Energy ◽  
Coarse Sand ◽  
Engineering Properties ◽  
Permeation Grouting ◽  
Injection Equipment ◽  
Fine Grained ◽  
Jet Grouting ◽  
Chemical Solutions ◽  
Grouting Materials

Grouting includes a range of processes that involve the injection of wet or dry materials into the ground to provide improved engineering properties. Common aims are to increase strength or stiffness or to reduce permeability within the mass of ground treated. The simplest process in concept is the permeation of the pore spaces with a fluid grout which then sets, and provides the desired properties. Jet grouting employs erosion and mixing using high energy jets, to attack a wide-ranging set of soils and applications. This paper, mainly, addresses permeation grouting for the improvement of soils, in terms of strengthening or reduction of permeability, and compensation grouting for the displacement of structures during subsurface exploration. The historical evolution of these two grouting processes is described leading up to present-day practice. Reference is made to grouting materials, methods of injection, equipment, limitations and verification for each type of grouting. The grouts used to make permeation grouting are mainly suspensions and chemical solutions. The suspensions penetrate well into soils with granulometry up to coarse sand. On the contrary, the chemical solutions penetrate satisfactorily in finer formations up to fine sands or coarse sludges. Because some chemical solutions are toxic or generally harmful to the environment and humans, an effort has been made internationally in recent years to replace them with inorganic fine-grained suspensions.

scholarly journals The Development of Practice in Permeation Grouting by using Fine-grained Cement Suspensions

2021 ◽  
Vol 9 (6) ◽  
Author(s):  
Dimitrios Christodoulou ◽  
Philotheos Lokkas ◽  
Alexandros Droudakis ◽  
Xenofon Spiliotis ◽  
Dorothea Kasiteropoulou ◽  
...  
Keyword(s):  
Coarse Sand ◽  
Engineering Properties ◽  
Permeation Grouting ◽  
Fine Grained ◽  
Chemical Solutions ◽  
Subsurface Exploration

Grouting includes a range of processes that involve the injection of wet or dry materials into the ground to provide improved engineering properties. Common aims are to increase strength or stiffness or to reduce permeability within the mass of ground treated. This paper, mainly, addresses permeation grouting for the improvement of soils, in terms of strengthening or reduction of permeability, and compensation grouting for the displacement of structures during subsurface exploration. The grouts used to make permeation grouting are suspensions and chemical solutions. The suspensions penetrate well into soils with granulometry up to coarse sand. On the contrary, the chemical solutions penetrate satisfactorily in finer formations up to fine sands or coarse sludges. Because some chemical solutions are toxic or generally harmful to the environment and humans, an effort has been made internationally in recent years to replace them with inorganic fine-grained suspensions.

scholarly journals Compressibility behaviour of remoulded, fine-grained soils and correlation with index properties

2000 ◽  
Vol 37 (3) ◽  
pp. 712-722 ◽  
Author(s):  
A Sridharan ◽  
H B Nagaraj
Keyword(s):  
Liquid Limit ◽  
Plasticity Index ◽  
Engineering Properties ◽  
Test Results ◽  
Index Properties ◽  
Initial Water ◽  
Fine Grained ◽  
Wide Range ◽  
The Relationship ◽  
Water Contents

Correlating engineering properties with index properties has assumed greater significance in the recent past in the field of geotechnical engineering. Although attempts have been made in the past to correlate compressibility with various index properties individually, all the properties affecting compressibility behaviour have not been considered together in any single study to examine which index property of the soil correlates best with compressibility behaviour, especially within a set of test results. In the present study, 10 soils covering a sufficiently wide range of liquid limit, plastic limit, and shrinkage limit were selected and conventional consolidation tests were carried out starting with their initial water contents almost equal to their respective liquid limits. The compressibility behaviour is vastly different for pairs of soils having nearly the same liquid limit, but different plasticity characteristics. The relationship between void ratio and consolidation pressure is more closely related to the shrinkage index (shrinkage index = liquid limit - shrinkage limit) than to the plasticity index. Wide variations are seen with the liquid limit. For the soils investigated, the compression index relates better with the shrinkage index than with the plasticity index or liquid limit.Key words: Atterberg limits, classification, clays, compressibility, laboratory tests.

scholarly journals The Making of Catalogues of Very-High-Energy γ-ray Sources

Universe ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 421
Author(s):  
Mathieu de Naurois
Keyword(s):  
Galactic Plane ◽  
Population Studies ◽  
High Energy ◽  
Cherenkov Telescopes ◽  
Background Rejection ◽  
Fine Grained ◽  
Very High Energy ◽  
Advanced Analysis ◽  
Γ Ray ◽  
Very High

Thirty years after the discovery of the first very-high-energy γ-ray source by the Whipple telescope, the field experienced a revolution mainly driven by the third generation of imaging atmospheric Cherenkov telescopes (IACTs). The combined use of large mirrors and the invention of the imaging technique at the Whipple telescope, stereoscopic observations, developed by the HEGRA array and the fine-grained camera, pioneered by the CAT telescope, led to a jump by a factor of more than ten in sensitivity. The advent of advanced analysis techniques led to a vast improvement in background rejection, as well as in angular and energy resolutions. Recent instruments already have to deal with a very large amount of data (petabytes), containing a large number of sources often very extended (at least within the Galactic plane) and overlapping each other, and the situation will become even more dramatic with future instruments. The first large catalogues of sources have emerged during the last decade, which required numerous, dedicated observations and developments, but also made the first population studies possible. This paper is an attempt to summarize the evolution of the field towards the building up of the source catalogues, to describe the first population studies already made possible, and to give some perspectives in the context of the upcoming, new generation of instruments.

scholarly journals Performance of electrokinetic treatment of fine-grained problematic soils

2021 ◽  
Vol 9 (4B) ◽  
Author(s):  
Abiola Ayopo Abiodun ◽  
◽  
Zalihe Nalbantoglu ◽  
Keyword(s):  
Low Voltage ◽  
Soil Depth ◽  
Experimental Tests ◽  
Interactive Effects ◽  
Engineering Properties ◽  
Laboratory Model ◽  
Fine Grained ◽  
Electrode Length ◽  
Problematic Soils

Electrokinetic (EK) treatment is an innovative, cost-effective in situ ground modification technology. The EK treatment uses a combination of low-voltage direct-current, electrodes, and ionic solutions across problematic soil to improve the ground conditions. This study aims to model the effect of changing electrode length (le) on the performance of the EK treatment on the engineering properties of fine-grained problematic soils. The consideration of the changing electrode lengths (le), varying soil depths (ds), and lengthwise anode to cathode distances (dA↔E), in the soil block samples, is in the form of the laboratory model test tank. The significant performance of the experimental tests was with changing electrode lengths of 0.25le (7.5 cm), 0.50le (15.0 cm), 0.75le (22.5 cm), and 1.0le (30.0 cm). The study analyzed the test data obtained from the Atterberg limit and one-dimensional swelling tests at different extraction points of the EK treated soils in the test tanks. Furthermore, the study carefully analyzed the effect of changing electrode length (le) on the performance of the EK treatment. The results of the Design of Experiment (DOE) model analysis revealed that the effect of changing electrode length (le) on the plasticity index (PI), and swelling potential (SP) of the EK treated soils, was significant. For a specific soil depth (ds), the electrode lengths (le) of 0.50le and 0.75le were significantly effective in reducing the PI, and the SP of the EK treated soils. Unlike other studies in the literature, the use of DOE analysis in the present study enabled the detection of the significant input factors and their interactive effects on the PI and the SP, thus, enabling the practicing engineers to navigate accurate design models for large in situ applications.

scholarly journals Engineering properties of fine grained soils of Kathmandu Valley, Nepal

1996 ◽  
Vol 14 ◽  
Author(s):  
T. P. Katel ◽  
B. N. Upreti ◽  
G. S. Pokharel
Keyword(s):  
Geotechnical Properties ◽  
Engineering Properties ◽  
Soil Conditions ◽  
Kathmandu Valley ◽  
Construction Sites ◽  
Engineering Construction ◽  
Fine Grained ◽  
The Past ◽  
Shearing Resistance ◽  
Watershed Boundary

This paper primarily deals with the distribution, and engineering and geotechnical properties of fine grained soils in the Kathmandu Valley. Not much studies have been done on these soils in the past except at some engineering construction sites such as bridges and heavy buildings. Very little data are available on the engineering and geotechnical properties of soils of the valley (IOE, 1983a, 1983b, 1986a, 1986b, 1986c; Koirala et al., 1993; Sadaula, 1993; Shakya, 1987; Soil Test, 1990a, 1990b). The authors conducted detailed laboratory studies on the soils of the Thapathali and Ratnapark areas in the central part of the Kathmandu Valley and the results are presented and discussed. An attempt is also made to broadly evaluate the soil conditions of the valley based on the available data from previous studies conducted by various agencies. The soils of the Kathmandu Valley are mainly produced by weathering of rocks within its watershed boundary. They are in most part lacustrine and fluvial in origin and composed of clayey, silty, sandy and gravely sediments. The maximum thickness of the sediment is found in the central part (550 m at Bhrikutimandap) and southern part (>457m at Harishidhi) of the valley. The engineering properties, basically the index properties such as grain size, natural moisture content specific gravity, Atterberg limits; and the mechanical properties such as penetration resistance, cohesion, unconfined compressive strength, compressibility as well as angle of shearing resistance of fine grained soils were determined and found to vary considerably both in horizontal and vertical directions. The bearing capacity and settlement values of the soils were also determined. It is commonly found that most of the buildings in the Kathmandu Valley are founded on isolated or strip types of foundations and the foundation depth is between 1 and 1.5 m. The study of soil properties of the Kathmandu Valley indicates that the heavy loaded structures should be founded on either raft, mat or pile types of foundation.

Fine-grained BNT-based lead-free composite ceramics with high energy-storage density

2019 ◽  
Vol 45 (16) ◽  
pp. 19895-19901 ◽  
Author(s):  
Weigang Ma ◽  
Pengyuan Fan ◽  
David Salamon ◽  
Suwadee Kongparakul ◽  
Chanatip Samart ◽  
...  
Keyword(s):  
Energy Storage ◽  
High Energy ◽  
Lead Free ◽  
Energy Storage Density ◽  
Composite Ceramics ◽  
Storage Density ◽  
Fine Grained ◽  
High Energy Storage Density ◽  
High Energy Storage

scholarly journals Pyrite Textures, Trace Elements and Sulfur Isotope Chemistry of Bijaigarh Shales, Vindhyan Basin, India and Their Implications

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 588
Author(s):  
Indrani Mukherjee ◽  
Mihir Deb ◽  
Ross R. Large ◽  
Jacqueline Halpin ◽  
Sebastien Meffre ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Sulfur Isotope ◽  
Volcanic Rocks ◽  
Central India ◽  
High Energy ◽  
Vindhyan Basin ◽  
Mean Values ◽  
Fine Grained ◽  
Sedimentary Pyrite

The Vindhyan Basin in central India preserves a thick (~5 km) sequence of sedimentary and lesser volcanic rocks that provide a valuable archive of a part of the Proterozoic (~1800–900 Ma) in India. Here, we present an analysis of key sedimentary pyrite textures and their trace element and sulfur isotope compositions in the Bijaigarh Shale (1210 ± 52 Ma) in the Vindhyan Supergroup, using reflected light microscopy, LA-ICP-MS and SHRIMP-SI, respectively. A variety of sedimentary pyrite textures (fine-grained disseminated to aggregates, framboids, lags, and possibly microbial pyrite textures) are observed reflecting quiet and strongly anoxic water column conditions punctuated by occasional high-energy events (storm incursions). Key redox sensitive or sensitive to oxidative weathering trace elements (Co, Ni, Zn, Mo, Se) and ratios of (Se/Co, Mo/Co, Zn/Co) measured in sedimentary pyrites from the Bijaigarh Shale are used to infer atmospheric redox conditions during its deposition. Most trace elements are depleted relative to Proterozoic mean values. Sulfur isotope compositions of pyrite, measured using SHRIMP-SI, show an increase in δ34S as we move up stratigraphy with positive δ34S values ranging from 5.9‰ (lower) to 26.08‰ (upper). We propose limited sulphate supply caused the pyrites to incorporate the heavier isotope. Overall, we interpret these low trace element signatures and heavy sulfur isotope compositions to indicate relatively suppressed oxidative weathering on land during the deposition of the Bijaigarh Shale.

Permeation grouting of a fine-grained pyroclastic soil

2006 ◽  
Vol 10 (4) ◽  
pp. 135-145 ◽  
Author(s):  
S. Lirer ◽  
A. Flora ◽  
A. Evangelista ◽  
L. Verdolotti ◽  
M. Lavorgna ◽  
...  
Keyword(s):  
Permeation Grouting ◽  
Fine Grained ◽  
Pyroclastic Soil

Microstructural Design by Controlled Crystallization of Metallic Glasses

2003 ◽  
Vol 806 ◽  
Author(s):  
Uwe Köster ◽  
Rainer Janlewing
Keyword(s):  
Glass Transition ◽  
Metallic Glasses ◽  
Nanocrystalline Materials ◽  
Nanocrystalline Alloy ◽  
High Energy ◽  
Fine Grained ◽  
Annealing Conditions ◽  
Diffusion Controlled ◽  
Microstructural Design ◽  
Vacuum Condensation

ABSTRACTNanocrystalline materials can be produced e.g. by high energy ball milling or vacuum condensation; these methods require powder compaction as a final step. In another route - the nano-crystallization - metallic glasses are used as precursors for nanocrystalline materials without any porosity. The conditions for achieving an ultra-fine grained material by crystallization are small growth, but large nucleation rates. Whereas in Fe-Ni-B glasses the finest microstructure is produced at annealing temperatures above the glass transition close to the maximum of the nucleation rate, in Zr-based metallic glasses nanocrystallization was found to proceed only at relatively low temperatures below the glass transition. The aim of this contribution is to study systematically the micromechanisms involved in the microstructural design.Crystallization was studied in detail in Fe-Ni-B and Zr-based metallic glasses by means of TEM, X-ray diffraction and DSC. Nucleation and growth rates were estimated from crystallization statistics. By modeling the obtained time-dependent nucleation rates in the framework of diffusion controlled classical nucleation all relevant crystallization parameter could be derived. Using these data TTT-diagrams could be drawn and annealing conditions deducted, e.g. for the formation of a nanocrystalline alloy.Isothermal DSC plots for polymorphic crystallization can only be explained with a very significant decrease in the growth rate at later stages. Such a decrease is assumed to result from stresses building up during crystallization beyond the percolation limit for the crystalline phase; under this condition stresses resulting from the volume change during crystallization cannot be compensated by viscous flow as in the case of isolated crystals in an amorphous matrix.

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