In this paper, a simple expression to predict the average diameter of columns created with single, double and triple fluid jet grouting is proposed considering both energy eroding resistance soil. The injection system (single, or triple) composition injected fluids are taken into account on basis theoretical analysis turbulent diffusion submerged jets. Instead separately air shrouding fluid, parameter introduced which represents beneficial effect in reducing energetic dissipation external...

SRAM stability during word line disturb (access disturb) is becoming a key constraint for V/sub DD/ scaling (Burnett, 1994). In this paper we present design methodology access disturb. methodology, the margin (ADM) defined as ratio of magnitude critical current to maintain (I/sub CRIT/) sigma I/sub CRIT/. Using ADM figure merit, enables one project cell due process variations, e.g. T/ variation, cell. statistical analysis, required an application requirement such array size and available...

Theoretical modelling of the mechanical phenomena induced by jet grouting is presented. The analysis developed for single-fluid method. propagation across space included between injection nozzles and intact soil first modelled on basis theory submerged flows. Different possible interaction modes are then assumed gravels, sands clays, according to results previous experimental investigations. In case grout seepage considered be most relevant mechanism. For sandy soils, injected fluid...

A methodology for cost-effective design of jet grouted water-sealing bottom plugs is presented in this paper. These massive barriers, made partially overlapping columns, are required to ensure temporary waterproofing excavation areas and adequate uplift resistance against water loads. Therefore, the proposed calculation procedure simultaneously focuses on structural performance continuity plug. The may be optimized by considering possibility reducing column length, performing injections only...

In spite of being one the most popular ground improvement techniques, jet grouting is often viewed with suspicion, its properties underestimated and role downgraded to provisional or subsidiary, mostly because lack reliable methods manage uncertainty. The random composition scattered material observed at small scale laboratory tests lead designers assume arbitrarily unjustified over-conservative strength. A methodology herein introduced quantify uncertainty, characterising different factors...

The author presents evidence that very small hydraulic gradients should be used in laboratory permeability tests to minimize errors arising from seepage-induced consolidation. These will carried forward practice significant ways. must such the effective stresses are substantially less than maximum past stress. In cases of normally consolidated soils, there always induced errors: softer clay, greater errors. seem compounded by conventional constant and falling head tests, because high...

This Paper presents a new analysis procedure for the constant rate of deformation consolidation test. The test utilizes piecewise linearization one-dimensional non-linear finite strain theory and solves properties by an inverse without any prioriassumptions about form these relationships. proposed method is evaluated simulation laboratory experimentation. shows good agreement between calculated corresponding input values. Similar found experimental validation computed independently, directly...

This paper deals with the design of jet-grouting cut-offs for dams. Available information from several cases is first reviewed, pointing out differences between projects concerning dams under construction and operational ones. Various dam types treatment schemes are considered; functions requirements defined; possible solutions proposed. Particular attention devoted to occurrence discontinuities along cut-offs, which may derive two main factors: deviation axes variation jet-column's...

Abstract This paper illustrates the results of an experimental study on sand–bentonite mixtures for their use as confinement barriers solid waste landfills. The have been prepared parametrically varying percentage bentonite. sample preparation method was established willing to simulate compaction processes site. In fact, compacted samples were tested following two different stress-wetting paths representative possible stress and imbibition sequences occurring a landfill barrier. first case,...

An experimental investigation was carried on sand-bentonite mixtures, prepared with various proportions of its components. The samples were compacted by Standard Proctor procedure, in order to simulate the situ placement method employed for earth embankments and landfills base layers. By analysing results compaction tests different structure types are identified depending bentonite content. For a small amount bentonite, mixture keeps properties granular soils, while higher contents there is...

Abstract The successful calculation of the progress consolidation requires that both theory used to model field problem and material properties by must be appropriate suitable. Thus testing procedure provide reliable consistent information on behavior. Further, test accompanied methods analysis will produce values are theory. This paper presents a summary existing laboratory determine soils. Emphasis is placed data. It shown all currently contain inherent simplifying assumptions. These...

The role of pore water chemistry on particle aggregation and soil formation during sedimentation process has been investigated for a kaolinite clay suspensions. modification surfaces charge properties minerals induced by different rules the particles arrangement. As consequence, at volume scale behaviour in turn physical, mechanical hydraulic formed skeleton are changed. Sedimentation tests several suspensions showed influence settling self-weight consolidation stages. Hydraulic conductivity...

The paper focuses on the role of jet grouting tunnel support, although influence supplementary techniques is also considered. For this purpose, experience gained from two well documented case histories presented. Reported observations and experimental data have been selected in order to help identification proper design limit states. Jet has proven be quite effective, allowing tunnelling very difficult conditions, but some failures recorded. Failure mechanisms can classified according three...

In this paper we analyze a possibility of manufacturing and implementation Schottky diodes in the smart power circuits. Three different diodes, three technologies, are realized Si SiC processes. The electrical characterizations with I–V–T C–V measurements done for all structures. It is shown that based also suitable to be integrated typical

The jet grouted soils are very heterogeneous and thus the statistical methods normally used to define strength of artificial construction materials become extremely conservative. To quantify mechanical effects variability on characteristic samples dimensions, random spatial variation firstly explored interpreting field laboratory tests with Random Field theory. Then is reproduced a large volume material together imaginary coring different sizes uniaxial compression testing. This calculation...

In recent years, in the automotive sector, devices that need a regulated DC supply voltage have increased. DCDC switching converters are best solution terms of performance, cost, and efficiency. Among converters, Step-Down converter (or Buck converter) is very important. The high number these installed on car requires reduction cost for system, with simple implementation, but maintaining comparable performances more complex expensive design. this article, an Asynchronous Constant T <inf...