[9] have reported the results from a centrifuge testing campaign of the caisson response under approximately N = 106 load cycles that considered different soil conditions ranging from sand over clay to solely-deposited sand. Although the research itself dealt with the knowledge gaps associated with rotation accumulation, the effects of geo ...Web

Quartz sand was used for all centrifuge model tests with the unit weight of 15–16 kN/m 3 and the relative density of D r =50 and 70%. The tested soil is classified as poorly graded sand (SP) according to the Unified Soil Classification System (Fig. 2).The properties of crushed quartz sand were reported by Lee et al. [38].The sand had a …Web

The sand materials used in centrifuge model tests are Ottawa-F65 sand. Ottawa F-65 sand is a clean (less than 0.5% fines), sub-rounded to sub-angular whole grain silica sand, provided by US Silica, in Ottawa, ... For the uniform quartz sand and the well-graded sandy silts, ...Web

For continuous and efficient oil/water separation and adsorption of dyes, coconut shell powder was grafted onto the surface of quartz sand by dip-coating method to make coconut shell powder-covered quartz sand filter media (CSQS) with superhydrophilic and underwater superoleophobic properties and superoleophilic and underoil highly …Web

DOI: 10.1007/PL00010913 Corpus ID: 54864536; Effect of particle size distribution on pile tip resistance in calcareous sand in the geotechnical centrifuge @article{McDowell2000EffectOP, title={Effect of particle size distribution on pile tip resistance in calcareous sand in the geotechnical centrifuge}, author={Glenn R. …Web

A series of centrifuge cone penetration tests were performed in loose and dense silica sand at g-levels ranging between 20 and 100 with corresponding overconsolidation ratio (OCR) between 1 and 5.Web

The use of shear wave velocity (V s) measurements as an in situ test for evaluation of liquefaction potential has increased substantially due to its advantages. Relatively large numbers of studies have been performed to establish the correlation between V s and liquefaction resistance (CRR) of clean sands. Usually, natural sands …Web

Cone penetra tion tests in dry and saturated Tic ino sand. ( 1992) investigated the crushability potential of Ticino sand. using an oedomet. beyond which extensive grain crushing started to occur ...Web

The Erith quartz sand used was laboratory dry, fine and fairly uniform with 80% of its grains between 0.125 mm and 0.25 mm giving a uniformity coefficient of 1.5. The average unit weights achieved in the centrifuge tests were 16 kN m −3 and 14.5 kN m −3 for dense and loose packings, respectively.Web

The quartz sand was pretreated with hydrochloric acid (36–38%, 12 mol/L) and deionized water following the procedure used in our previous study (Hou et al., 2017) to remove the metal oxides and other impurities from the sand surface. ... The effluent was collected in 25 mL centrifuge tubes and used to measure the concentration (C) ...Web

Centrifuge modelling is an experimental test method used to reproduce large scale engineering problems with small-scale physical models. The aim is to induce stresses in the model which are equal to those that would be experienced in the full-scale equivalent being investigated, known as the prototype. ... (20 MPa for quartz sands) ...Web

In this work, a smart quartz sand (OD-SiO2 @sand) with controllable wettability was designed as a filter media for efficient oil-water mixtures and water in oil …Web

The quartz sand and carbonate sand are used in the tests as shown in Fig. 8. The quartz sand is Fujian standard sand, and its specific gravity is 2.65. The carbonate sand is taken from the coast of an island in the South China Sea, and its specific gravity is 2.81. The particle size, the maximum and minimum void ratios are listed in Table 2.Web

In model Test 3, sand pile drain materi al was used of quartz sand having permeability coefficient of 7.7×10-5 m/sec, of 0.5 mm and of 0.2 mm. The methocelWeb

Quartz sand . 80 . 45 . 55 . 21 . 1.25 . 1.18 . 1.33 ... subsequently developed logarithmic spiral model to a hyperbolic spiral model on fault rupture trace based on centrifuge model tests for ...Web

Leth (2011) showed, using the DTU centrifuge, that the sand surface will settle around 0·2 mm for a density and load cycle similar to one reported in this paper. The pile testing procedure for the piles installed in-flight is outlined below. ... 1986) represents the crushing strength of quartz sand.Web

Centrifuge modeling at a gravity field of 40 g allowed upscaling the effective stresses within the specimen ... poorly graded quartz sand (US Silica, Friederick, Maryland). Grain size and packing ...Web

In centrifuge modeling, it is important to evaluate the in-flight strength and stiffness parameters of the soil model to understand soil behavior. Both the shear-wave …Web

The results of the centrifuge experiment of shallow foundations with surcharges of three-story and nine-story buildings on liquefiable sand are presented in …Web

Nevada Sand (#120) was used during the VELACS Research Program (Verification of Liquefaction Analyses by Centrifuge Studies) by the Earth Technology Corporation in the 1990s.Web

The characteristics of the quartz sand and silt are shown in Table 2. Fig. 1 shows the grain-size distribution curves of the quartz sand and the silt used in the model tests. The permeabilities of the quartz sand and the silt with a relative density (Dr) of 40% are 6.8×10 −5 and 7.4×10 −6 m/s respectively.Web

Fontainebleau sandstone outcrop is a prime example of a simple natural porous medium because of its pure mineral composition (0.995 Quartz) and an almost constant grain size in large sample blocks.Web

To efficiently and synchronously separate oil/water mixture and adsorbed dyes, corn-cob-covered quartz sand (CCQS) filter media with underwater superoleophobic qualities and underoil extremely …Web

Two in-flight shear wave velocity measurement systems were developed to perform the subsurface exploration of shear wave velocity in a centrifuge model. The …Web

The transparent sand used in this investigation was made from fused quartz and pore fluid with an identical refractive index. The pore fluid was a blend of N-Paraffin Norpar 12 and White Oil 15 in the weight ratio of 1:4, having stable chemical properties and a refractive index of 1.4585 at 24 °C.Web

Stewwart DP, Randolph ME (1991) A new site investigation tool for the centrifuge. In: Proceedings of international conference centrifuge 91, Boulder, 13–14 June, pp 531–538. Wichtmann T, Triantafyllidis T (2009) Influence of the grain-size distribution curve of quartz sand on the small strain shear modulus G max. J Geotech Geoenviron …Web

Correlation between the Shear-Wave Velocity and Tip Resistance of Quartz Sand in a Centrifuge. Authors: Jae-Hyun Kim, Ph.D., Yun Wook Choo, Ph.D., and Dong …Web

The transport of colloid in unsaturated porous media affects the migration of contaminants and thus is closely related to groundwater resources protection. To figure out the combined effects of grain size, colloid concentration and injection flow rate on montmorillonite colloid transport characteristics in unsaturated quartz sand, a total of 27 …Web

Quartz sand has often been used to simulate porous media in model leaching studies [Citation 10]; however, the ... 10, 15 and 20 mg L −1) in 50 mL centrifuge tubes. Each mixture was equilibrated as in the first batch for 24 h. The supernatants were filtered through a 0.22 μm filter, after which the Cd(II) concentrations in the filtrate were ...Web

Two centrifuge model tests were conducted to study the land subsidence affected by the different building distances. The distance between two adjacent buildings in the building group was 20 and 30 m in the prototype, and the running time of the centrifuge was 6 and 8 h, respectively. ... The hardness of quartz is large. So, the sand layer is ...Web

Quartz Sand. Quartz sands and sandstones are gray to light gray in color, medium-grained, with some fine-grained argillaceous varieties. From: Petroleum Geology of the South …Web

The retention time of quartz sands is obviously less than that of calcareous sands, illustrating that calcareous sands has more particle breakage than quartz sands. ... Effect of particle size distribution on pile tip resistance in calcareous sand in the geotechnical centrifuge. Granul. Matter., 2 (4) (2000), pp. 179-187, 10.1007/PL00010913 ...Web

The quartz sand and CaCO 3 easily yielded water to the Rhizons but yielded little water during centrifugation. The clays released their water when centrifuged yet Rhizon extraction from clays was relatively slow. ... This problem can be lessened in centrifugation by filling centrifuge tubes to the top and thus minimizing headspace (Fig. 6) but ...Web

A kind of fine quartz sand with mean particle size of 0.19 mm was selected to avoid the particle effect for the centrifuge model. Its specific gravity is 2.65 with the maximum and the minimum dry unit weight of 16.6 kN/m 3 and 13.8 kN/m 3, respectively.According to the Unified Soil Classification System, the sand is classified to …Web

The extraction method for quartz sand before SEM observation was as follows: (1) To remove free iron, the dried sample was placed in centrifuge tube with sodium dithionite, sodium citrate (0.3 mol/L) and sodium bicarbonate solution (1 mol/L) and heated in a water bath. The solution was then separated by centrifuge until clear.Web

1. Introduction. Calcareous sands are the product of various biological, physical and chemical effects. They are widely distributed in low latitude coastal areas, e.g. the Persian Gulf, the Red Sea, the west continental platform of Australia and the South China Sea [1]pared with the quartz sand, calcareous sand has two significant …Web