Three-layer Clay Research Articles

Using Geotextile to Reduce the Required Thickness of Sub Base Layer of the Road and Improvement in CBR Value

Soil fabrics (geotextiles) are a permeable textile structural composition, and are mainly use in civil engineering applications associated with soil, rocks, or water. The American specifications (ASTM-D1316) indicated in the definition of this type of fabrics that they are use in some installations for civil and structural engineering, as the traffic increases day by day, many road related problems happen. Due to the heavy volume and heavy traffic the roads were damage very early, to avoid such a situation, we can use the geotextile.Geotextiles can be roughly in to two-type woven and nonwoven, in this research, non-woven (geotextile-50 pressed) was use in the work. The effect of geotextile sheets on improving the load-settlement characters of five-layered soil (three-layer clay, two-layer recycle concrete aggregate); moreover, the use of geotextiles has been study to reduce the required thickness of the sub-base layer of the road. Given the widespread use of bearing testing rate in the projects of road construction, it has used this test in this research, it was a test California bearing ratio (CBR) on the soil of five layers including the rubble of recycled concrete layer recycled (RCA) in the top (sub base)) and the clay soil place bottom(subgrade)These tests were conduct different the situations, including the use of test geotextile and test not use geotextile. In this research, the performance of nonwoven geotextiles, interconnect between the soft subgrade and the sub-base of the recycle of the recycle concrete aggregate (RCA) in the flexible paving system was good as the Geotextiles improve and increase the CBR value about (20%) of the road layers as well as the geotextile worked on reduce permeability about (50%).Geotextile also worked to separate or (isolate) two materials that are not alike, such as two soil layers with different properties, such as separating the subgrade layer from the subbase layer.

Effects of cone tip roughness, in-situ stress anisotropy and strength inhomogeneity on CPT data interpretation in layered marine clays: numerical study

This paper explores the effects of cone tip roughness factor, soil in situ stress ratio and strength non-homogeneity on cone tip resistance in three-layer clay deposits, aiming at presenting a general CPT data interpretation framework to extract soil layered profiles and strengths. Large deformation finite element (LDFE) analysis has been carried out, simulating continuous penetration of the standard cone penetrometer from the seabed surface, with the consideration of cone tip roughness factor, in situ stress ratio and soil strength non-homogeneity within a practical range. In the LDFE analyses, a thin relatively stiff or soft clay layer was interbedded in a uniform or NC clay deposit, with various strength ratios between two successive layers and thickness ratios of the thin layer to the cone diameter explored.The results have shown that the noted factors have significant influence on net cone penetration resistance in stratified deposits. These influences in the layered deposits were found to be similar in magnitude to those on the cone limiting resistance in a single clay layer, leading to the resultant influence on a thin layer correction factor for cone penetration resistance minimal. This was confirmed by the evidence of the evolving soil flow mechanisms around the cone tip. Therefore, the design charts and formulas developed for a smooth cone in uniform three-layer soils are applicable for delineating layer boundaries and interpreting the undrained shear strength of each identified layer for a partially rough cone in three-layer non-homogeneous clay deposits. However, the cone tip roughness factor was shown to have an influence in the layer boundary identification, especially for the cone penetration from a stiff layer to a soft layer.

Numerical Modeling of Spudcan Deep Penetration in Three-Layer Clays

This paper reports the results from numerical modeling of spudcan deep penetration through three-layer clays. Two typical seabed strength profiles commonly encountered in the field, and identified as critical for potential punch-through failure, were considered: (1) uniform stiff-soft-stiff clay and (2) nonuniform clay with an interbedded stiff clay layer. Three-dimensional large deformation finite-element (LDFE) analyses were carried out with and without simulating strain softening and strain rate dependency of the shear strength. The results were compared with previously published LDFE results and centrifuge test data. A detailed parametric study was undertaken, varying the relevant range of layer thicknesses (relative to the spudcan diameter), strength ratios, normalized strength, and strength nonhomogeneity. Punch-through and rapid leg penetration (for stiff-over-soft) and squeezing (for the reverse) were demonstrated by the penetration resistance profiles and associated soil failure mechanisms. The results emphasized that the resistance profile from a spudcan continuous penetration in a three-layer sediment (e.g., stiff-soft-stiff) may be significantly different from the combined profiles resulting from two separate analyses on first-second layers and second-third layers, even if an appropriate depth factor is accounted for. For uniform stiff-soft-stiff clays, the presence of the bottom stiff clay layer within a short distance of one diameter affected spudcan bearing response in the top layer and suppressed the potential for punch-through failure (apart from rapid leg run for t1/D=0.75 and su1s/su2=3). A trapped soil plug beneath the advancing spudcan, following penetration of the top stiff layer, caused the bottom stiff layer to be sensed earlier and led to enhancement of the limiting squeezing depth. For nonuniform clay with an interbedded stiff layer, spudcan bearing response was dominated by squeezing (with limiting squeezing depth of approximately 0.18D) in the top soft layer and potential punch-through and rapid leg run (for t2/D≥0.5 and su2/su3s=2.5) in the middle and bottom layers. In contrast to ISO recommendations, the soft soils in between the advancing spudcan base and the stronger layer did not squeeze out completely. Instead, some of the trapped material was forced into the underlying stronger layer. Punch-through distance was found to reduce significantly with increasing positive strength gradient of the bottom layer.

The influence of clay binder material on the physical properties of the CaNaA molecular sieve used in a hydrocarbon separation process

For various zeolite-binder mixtures, the mechanical properties and the sorption ability of the extruded products have been analyzed. We established an optimal composition of the binders amounting to 80% two-layer and 20% three-layer clay materials. The calcination temperature should be between 823 and 923 K. Acidic media are to be avoided in the manufacturing process.

Catalytic effect of smectite clays in hydrocarbon generation revealed by pyrolysis-gas chromatography

Temperature-programmed pyrolysis-gas chromatography of mixtures of expanding three-layer clays and Eocene Green River Formation kerogen gives insight into the differences in composition of pyrolyzates of specific sediments and of isolated kerogens. Argillaceous sediments containing less than about 2τ total organic carbon yield pyrolyzates containing primarily low molecular weight hydrocarbons in the gas condensate range whereas kerogens isolate from such sediments yield a broad range of volatile products including higher molecular weight hydrocarbons. Pyrolyzates of organic-rich sediments are much more similar in composition to pyrolyzates of isolate kerogens. The ration of expanding three-layer clays to organic matter in sediments apparently controls the degree of catalytic cracking so that argillaceous sediments relatively low in organic matter yield volatiles rich in low molecular weight hydrocarbons due to more carbon—carbon bond cleavage. These observations are related to gas and gas condensates of the northern Gulf Mexico basin and in Indonesia and to oil in the North Sea area.

Thermal Chromatography in Source-Rock Analysis: ABSTRACT

Thermal chromatography or pyrolysis-gas chromatography of mixtures of expanding three-layer clays and sedimentary organic matter or kerogen gives insight into the differences in composition of pyrolyzates of specific sediments and isolated kerogens. Argillaceous sediments containing less than about 2% kerogen-C yield pyrolyzates consisting primarily of low molecular weight hydrocarbons in the gas condensate range, whereas kerogens isolated from such sediments yield a broad range of hydrocarbons as in oil. Pyrolyzates of organic-rich sediments are similar in composition to pyrolyzates of isolated kerogens, being oil-like. The ratio of expanding three-layer (smectite) clays to organic matter in sediments apparently controls the degree of catalytic cracking, so that argillac ous End_Page 561------------------------------ sediments relatively low in organic matter yield low molecular weight hydrocarbons due to more carbon-carbon bond cleavage. Kerogens mixed with quartz, silica, alumina, calcium carbonate, kaolin, or illite yield pyrolyzates more similar to those of the respective kerogens alone. This is due ostensibly to a lack of catalytic activity of these minerals as compared with the catalytically active smectites. Smectitic argillaceous sediments that contain less than approximately 2% organic carbon are poor sources of oil, although they may be productive of gas and gas condensate. These observations are related to gas and gas condensates of the northern Gulf of Mexico basin and in Indonesia, and to oil in the North Sea area. End_of_Article - Last_Page 562------------

Clay Stabilization Agents - Their Effectiveness in High-Temperature Steam

Laboratory data indicated that commercially available clay stabilization polymers may be beneficial in maintaining greater sustained formation permeabilities in clayey formations subjected to high-temperature steam injection. Polymers evaluated varied in high-temperature clay stabilization properties and resistance to hydrochloric acid. Result from several field applications of one polymer are included. Introduction Steaming encompasses the entire recovery spectrum involving primary, secondary, and tertiary approaches. It has been reported that oil retrieved by steam methods represents 90% of all the oil produced by current enhanced recovery techniques. Steam recovery methods often are applied in low-temperature, poorly consolidated, shallow geological laydowns which frequently are characterized by high concentrations of clay minerals. When exposed to steam, these untreated clays may cause severe matrix permeability reduction. Sometimes this loss of rock permeability is not fully recoverable. As a consequence, reservoir depletion efficiency may be reduced. Therefore, it is plausible to predict that effective clay mineral control will play a vital role in steam recovery of hydrocarbons from clay-bearing formations.Sand problems can be caused by inadequate clay control because clay minerals often serve as cementing materials in rock formations. Should the clay swell or migrate, cementation between sand grains can be damaged or destroyed, resulting in sand production. This has been reported to be a recurring problem in numerous cyclic steam (huff ‘n’ puff) wells in which the produced sand periodically must be bailed out of the wellbore. Clay Damage Mechanisms Numerous forms of clay minerals exist in subterranean strata. Their permeability damage potential is related to structure, orientation, cation exchange capacity, and geological laydown pattern along with the existing cation environment. Clays can be classified into two basic types:expanding andlow water absorbing. Smectite (montmorillonite), a three-layer clay, is considered the most expandable in the presence of water, particularly fresh or low-salinity waters similar to those associated with steaming techniques. Mixed-layer clays, containing smectite intermixed with other clays, also are classified as expandable. In addition to causing pore plugging, expanding clays can result in a release of other clay and silica fines which tend to travel within the tortuosity of the interstices until points of lodgment or bridging occur. This can result in further restriction of pore-space dimensions and lower permeability, which are synonymous with reduced withdrawal rates. Low-water-adsorbing clays (e.g., kaolinite, illite, and chlorite) are common to many shallow as well as deep formations. Although these clays can be expected to cause less damage due to expansion than smectite, other formation damage associated with water-promoted disintegration, dispersion, and migration can occur.For an excellent description of clays most common to hydrocarbon-bearing reservoirs, reference is made to a paper by Hower. JPT P. 2121＾

Effect of solar radiation on poliovirus: Preliminary experiments

Solar radiation was found to have some inactivating effect on poliovirus type 1 in the absence of any natural or synthetic photosensitizing agent. Nontronite, a three-layer clay, displayed a protective effect against light or thermal inactivation. Photoinactivation of poliovirus in lake water was retarded by the presence of blue-green algae. The light inactivation was less important at a depth of 6 in.

Mechanisms of clay stabilization with inorganic acids and alkalis

A series of mono- and di-valent cation hydroxides, and certain strong acids, were allowed to react with a two- and a three-layer clay mineral (kaolin and montmorillonite) under conditions simulating those for normal soil stabilization in field practice, i.e. mixed, remoulded, and moist-cured at a moisture content and density approximating optimum compaction conditions. The progress of reaction was followed over extended periods of time, up to two years. Changes in strength and volume were correlated with chemical and mineralogical changes in order to identify those bonding mechanisms which contribute to inorganic soil stabilization. For an additive level of 10% by weight dry clay basis (9.1% total dry solids basis) it was shown that several distinct stabilization mechanisms exist. One major mechanism is the surface coating of fabric units, and another the reinforcement of the soil by product formation in crevices, angularities, pore constrictions, and similar defects which influence the mechanical properties of the whole sample. The importance of these reactions to practical soil stabilization is thus demonstrated.

Distinction de l'aluminium tétracoordonné et hexacoordonné par fluorescence X. Premiers résultats

Following the oral comments of Dr. MERING at the last Réunion du Groupe Français des Argiles, we have attempted to define a method for testing the AlIV/AlVI ratio by means of a standard X fluorescence apparatus (SRS 1 Siemens). In the experimental conditions the positions of the K a line of tetracoordinate and hexacoordinate Al differ by about 6/100° (2 Q). The few authors who studied this question conduct their measurements by the graphic recordings of the lines. We propose a method based on cumulative countings which seems to provide good results, but the start up of thic method is rather delicate and necessitates some precaution. An interesting fact seems to arise from our first measurements : the AlIV/AlVI ratio obtained by means of fluorescence coincides rather rarely with the ratio calculated from the standard chemical analyses and we never found any three-layer clay mineral with purely siliceous tetrahedral sheets. In the actual state of our works we will not extrapolate these impressions based on a small number of results .

A Technique for Low‐Angle X‐Ray Diffraction Studies on Expanded Three‐Layer Clays

Soil Science Society of America JournalVolume 27, Issue 2 p. 241-242 Note A Technique for Low-Angle X-Ray Diffraction Studies on Expanded Three-Layer Clays† D. H. Fink, D. H. Fink Agronomy Department, Virginia Polytechnic Institute, BlacksburgSearch for more papers by this authorG. W. Thomas, G. W. Thomas Agronomy Department, Virginia Polytechnic Institute, BlacksburgSearch for more papers by this author D. H. Fink, D. H. Fink Agronomy Department, Virginia Polytechnic Institute, BlacksburgSearch for more papers by this authorG. W. Thomas, G. W. Thomas Agronomy Department, Virginia Polytechnic Institute, BlacksburgSearch for more papers by this author First published: 01 March 1963 https://doi.org/10.2136/sssaj1963.03615995002700020046x † Contribution from the Agronomy Department, Virginia Polytechnic Institute, Blacksburg. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume27, Issue2March-April 1963Pages 241-242 RelatedInformation

Interpretation of Chemical Analyses of Clays

Abstract As a means of distinguishing between the broad groups of flay minerals, chemical analysis may be a valuable supplement to other methods, but rarely will it remove the necessity for other methods, X-ray analysis in particular. The two- and three-layer clay minerals may be distinguished by the SiO2 · Al2O3 ratio or SiO2 · sesquioxide ratio, but these ratios do not provide criteria for dividing either class. Among the three-layer clays, which embrace montmorillonite, nontronite, and the diverse hydrous micas, non-exchangeable K is a better criterion. It seems probable that montmorillonite, as found in bentonite deposits, does not contain significant amounts of non-exchangeable K, whereas all known hydrous micas contain significant, although widely variable, amounts of non-exchangeable K. The greatest value of chemical analysis inheres in the fact that by means of calculation the specific nature of the isomorphism may be determined. But the degree of confidence that can justifiably be placed in the calculated isomorphism depends on the purity of the sample analyzed. SiO2 as impurity may be shown by an excess of calculated Si++++ ions, or by a deficiency of octahedral cations. It also affects the calculated isomorphism of the tetrahedral layers of the lattice by reducing its Al content. On the other hand, Al2O3 as impurity affects the calculation in the opposite way; that is, it reduces the number of Si++++ ions per unit cell, while increasing both tetrahedral and octahedral Al+++ ions. Fe as impurity has essentially the same effect as Al. In some samples it is possible to detect SiO2 as impurity by means of calculation.