Physical Properties Of Sand Research Articles

THE INFLUENCE OF RIVER AND VOLCANIC SAND AS COATINGS ON POLYPROPYLENE WASTE COARSE AGGREGATE TOWARDS CONCRETE COMPRESSIVE STRENGTH

One of the most important factors used to determine the compressive strength of concrete is its aggregate and matrix adhesion. This study examines the surface properties of polypropylene (PP) waste coarse aggregate (PWCA) to determine the influence of sand. The PWCA was made from the PP waste and different types of coating such as PWCA-R (river sand) and PWCA-V (volcanic sand), with experimental tests conducted on the physical properties of sand and PWCA, while the compressive strength, FESEM and density of polypropylene waste coarse aggregate concrete (PWCAC). Concrete specimens were prepared by replacing natural coarse aggregate with PWCA in percentages of 0%, 25%, 50%, 75%, and 100%, varying the water-cement ratio by 0.3 and 0.42 and using polypropylene (PP) waste coarse aggregate (PWCA-R and PWCA-V) as the coating material. The results showed that fineness modulus (F.M) and water absorption of the river sand was higher compared to volcanic sand. The PWCA-V had higher density and specific gravity compared to PWCA-R. On the other hand, water absorption of the PWCA-V was lower than PWCA-R. The PWCA concrete had density which varies from 1740 kg/m3 to 2074 kg/m3. For both, the PWCA concrete compressive strength at 28 days with a 100% replacement ratio was reduced by 43% to 55% compared to the natural coarse aggregate (NCA) concrete with 0.3 and 0.42 water-cement ratios. Also, the structural efficiency of PWCAC decreased with an increase in replacement ratio. River sand adhered to the PWCA surface resulted in a better compressive strength value compared to the volcanic sand.

Grain morphology and strength dilatancy of sands

The presented experimental study, from micro to macro scale, assesses the effects of grain shape on the strength-dilatancy behaviour and physical properties of seven natural sands of different origins and mineralogical composition. The micro-scale has been characterised by processing two-dimensional image of grains, using the fractal analysis of particle contour to define their shape. The macroscopic material properties are evaluated performing direct shear tests at three different normal stresses, and measuring void ratios limit and angles of repose. An innovative method to interpret the experimental data obtained has pinpointed interesting relationships linking the morphological features of grains to the mechanical and physical properties of sands. Data confirm that the increase in grain shape irregularity produces an increase in all the variables investigated: void ratios limit, friction angles and dilatancy parameters.

Comparison of Grain Size Distribution and Grain Shape of Various Sand Samples

This study aimed to compare grain size distribution and grain shape of sands with different mineralogies and origins. Also, we attempted to investigate the changes in the physical properties of sands with different mineralogical properties. Four different sand samples taken from the Black Sea and Aegean regions were selected for experiments. Sands were named Type 1, Type 5, Type 9, and Type 13. A washing process was applied because clean sand was preferred for the experiments. Grain distributions were determined with wet mechanical analysis, and unwashed and washed samples were compared. The samples were classified as “poorly graded sand.” Mineralogical properties were determined by binocular microscope, X-ray, and SEM. When the samples were chosen, attention was given to selecting those with different source rock properties. Their origins were determined to be sedimentary, magmatic, and metamorphic. It was determined that Type 1 sand is volcanic, Types 5 and 9 sands are sedimentary, and Type 13 sand is metamorphic in origin. Additionally, Types 1, 5, and 9 sands were taken from the seashore, and Type 13 sand was taken from the riverside. Also, it was determined that Type 5 is a mixture of river and sea sand. It was understood that different mineralogical properties result in different physical properties. Besides, not only the mineralogy but also the origin (marine or the river) affects the grain distribution and shape. Marine or the river origin has more effect on grain distribution and shape than does mineralogy. However, mineralogy is important in determining specific gravity.

Experimental Investigation on Shear Strength and Liquefaction Potential of Rubber‐Sand Mixtures

The application of scrap tires as construction materials in civil engineering is one of the most promising ways to recycle this pollutant. The objective of this study was to investigate the shear strength and liquefaction potential of saturated rubber‐sand mixtures. Direct shear tests and cyclic triaxial tests were conducted on rubber‐sand mixtures at various rubber contents. It was found that the addition of rubber particles to sand changed the shear stress‐horizontal displacement development. The addition of rubber particles to sand improved the shear strength slightly and improved resistance to liquefaction significantly. Additionally, a hyperbolic model was proposed to describe the pore water pressure generation. This study demonstrates the effect of rubber particles on the physical properties of sand.

A geospatial model to quantify mean thickness of peat in cranberry bogs

Commercial cranberry (Vaccinium macrocarpon Ait.) is cultivated on postglacial deposits of peat capped by 0.3–1m of anthropogenic sand. Despite distinct soil layering, a general paucity of information exists on the physical properties of sand and peat in cranberry bogs. Field measurements and ground penetrating radar (GPR) were used to determine sand and peat thicknesses of 30 cranberry bogs in Massachusetts, United States. GPR-based estimates of peat volume and detailed soil maps were then used to develop a geospatial model of mean peat thickness (L*) in cranberry bogs. The model was applied to 505 cranberry bogs that covered in area of 2827ha. Based on model results and field measurements, average sand and peat thicknesses were 0.5 and 0.9m, respectively. For individual bogs, mean peat thickness exhibited considerable range, with deep peat (L*>1.8m) identified in 22% of the cranberry bogs. Peat was absent (L*=0m) in 26% of the cranberry bogs, which reflected modified upland or glaciolacustrine soils rather than peat. Using average thickness, nutrient concentration, and bulk density of peat and sand layers, a typical cranberry bog stores 750Mgha−1 of carbon, 22,900kgha−1 of nitrogen, and 790kgha−1 of phosphorus. We estimate that peat stores 91% and 78% (by mass) of carbon and nitrogen in cranberry bogs, respectively. In contrast, sand stores the majority of P (78% by mass) in cranberry bogs.

Laboratory Tests on Effectiveness of Environment-Friendly Organic Polymer on Physical Properties of Sand

The poor water stability, high penetrability, and low antierosion of sand affect the stability of the sandy soil slope. To understand the effectiveness of environment-friendly organic polymer on these physical properties of sand, a series of laboratory tests including water stability test, penetration test, and runoff erosion test of polymer reinforced sand were performed. The results of tests indicated that the organic polymers have obvious effects on the reinforced sand. The water stability of polymer reinforced sand had been improved strongly. All the reinforced sands with polymer ≥0.3% remained a stable structure at immersing time of 24 hours. The penetrability of the reinforced sand decreased with the increase of the polymer. The reinforced sand with polymer ≥7% was impermeable. The erosion resistance of sand increased with the increase of polymer content. With the polymer ≥4%, the sand surface kept intact with the scouring time more than 2 hours. The results could be applied as the reference for organic polymer reinforced sand engineering, especially for surface protection of embankment, slope, and landfill.

Effects of Biocementation Method on Direct Shear Stress and Unconfined Compressive Stress of Sand

Objectives: To explore bio-mediated method to strengthening soil engineering parameters. Methods: Besides, issues such as environmental pollutions engineers invent new methods for improving mechanical soil properties. During the last decade bacteria cultivation technique has become one of the innovative methods which are more capable compared with other methods. Results: The new method named Microbial Induced Calcite Precipitation (MICP) provides a suitable condition in order to derive calcite between sand particles by adding cultivated bacteria and cementation solution to it. In fact, reaction between these solutions creates strong bonds which lead to strengthening physical properties of sand. Conclusion: The direct shear test and unconfined compression test results demonstrate non-homogeneity distribution of solutions in the sand samples.

Hydrate morphology: Physical properties of sands with patchy hydrate saturation

The physical properties of gas hydrate‐bearing sediments depend on the volume fraction and spatial distribution of the hydrate phase. The host sediment grain size and the state of effective stress determine the hydrate morphology in sediments; this information can be used to significantly constrain estimates of the physical properties of hydrate‐bearing sediments, including the coarse‐grained sands subjected to high effective stress that are of interest as potential energy resources. Reported data and physical analyses suggest hydrate‐bearing sands contain a heterogeneous, patchy hydrate distribution, whereby zones with 100% pore‐space hydrate saturation are embedded in hydrate‐free sand. Accounting for patchy rather than homogeneous hydrate distribution yields more tightly constrained estimates of physical properties in hydrate‐bearing sands and captures observed physical‐property dependencies on hydrate saturation. For example, numerical modeling results of sands with patchy saturation agree with experimental observation, showing a transition in stiffness starting near the series bound at low hydrate saturations but moving toward the parallel bound at high hydrate saturations. The hydrate‐patch size itself impacts the physical properties of hydrate‐bearing sediments; for example, at constant hydrate saturation, we find that conductivity (electrical, hydraulic and thermal) increases as the number of hydrate‐saturated patches increases. This increase reflects the larger number of conductive flow paths that exist in specimens with many small hydrate‐saturated patches in comparison to specimens in which a few large hydrate saturated patches can block flow over a significant cross‐section of the specimen.

Properties of selected soils from the sub−arctic region of Labrador, Canada

Abstract Atotal of 212 soil profiles were described and assessed for physical and chemical properties during July 2006 as part of an Ecological Land Classification study along the Churchill River in central Labrador. Two major soil types were found in the study area along the Churchill River: Podzols and Organic soils. Podzolic soils covered approximately 60% and Organic soils occurred in 24% of the study area. Approximately 15% of the study area was classified as rock and other unconsolidated material. Summary results and a sub−set of the following soil units (from 10 soil profiles) are presented here and were distin− guished according to the Canadian System of Soil Classification (CSSC) (Soil Classifica− tion Working Group 1998): Orthic Humo−Ferric Podzol, Placic Ferro−Humic Podzol, Gleyed Humo−Ferric Podzol, Sombric Humo−Ferric Podzol, Gleyed Regosol and Orthic Luvic Gleysol. The basic properties of the soil units identified above included: (i) morpho− logical descriptions of soil profiles with differentiated horizons; (ii) field−texture tests were used to determine classes and physical properties of sands, silts, loams and occurrence of mottles; and (iii) a range of soil chemical composition of different horizons (e.g., pH, total organic carbon [TOC] and select metal concentrations) which indicated no anthropogenic contamination above background concentrations in the area.

Estimating Sand–Shale Formation Pore Pressure

This article presents a comprehensive evaluation method of estimating sand–shale formation pore pressure by using sonic velocity and other logging data. The method takes the influence of porosity, density, shale content, effective stress, and some other physical properties of sand–shale formation on sonic velocity into account. The influence and related logging data are combined to estimate the effective stress, and then pore pressure can be obtained by the effective stress principle. Using this method, software was developed and it applied in the well site. Its applications indicate that this method can accurately estimate the abnormal pressure of a sand–shale formation.

砂質土のP波速度と液状化強度に及ぼす飽和度の影響

The objective of the present study is to investigate the effects of the physical properties and confining stress on the Sr-P-wave velocity and Sr-liquefaction strength correlations for sandy soils. Based on a series of laboratory tests, following were concluded. (i) The effects of relative density, particle size and shape, pore water property and over consolidation ratio on Sr-P-wave velocity correlation is negligible. (ii) In the range of Sr smaller than 95%, P-wave velocity increases with increasing confining stress. (iii) P-wave velocity increases rapidly when the degree of saturation increases from 90% to 100% regardless of the physical properties of sand and confining stress. (iv) The effects of the confining stress and physical properties of sand on the correlation between the degree of saturation and liquefaction strength are minimal. (v) A decrease of Sr from 100% to 90% brings about 2.2 times increase of liquefaction strength unaffected by the physical properties of sand and confining stress. (vi) A decrease of Vp from about 1600 m/s to 350 m/s brings about 2.2 times increase of liquefaction strength.

A comparative study on the performance of sands rich and poor in fines in self-compacting concrete

Self-compacting concrete (SCC) as a special concrete, has practical advantages due to its mechanical performance and application easiness. However, a more careful study is needed at the stage of mixture proportioning. In order to produce SCC, a more voluminous but also a more viscous matrix is needed compared to concrete of normal workability. This may be achieved by using additional fillers with pozzolanic or inert nature. The employment of sands rich in fines may be a second alternative source of filler. However, the physical properties of sands rich in fines affect the performance of SCC in dual ways. In this study, the effects of the changes in the physical properties of sands (in particular the fine material content and type), on concrete performance were investigated. SCC mixtures containing four different sands (washed natural (WN) sand, washed crushed limestone (WCL) sand, crushed limestone sand with silt powder (CLS) and crushed limestone sand with clay powder (CLC)) were produced and the admixture requirements for each type of SCCs were determined. Test results suggest that, in order to produce SCC with the same consistency, admixture requirement may change with the physical properties of sands used. When compared to SCCs prepared with washed sand (poor in fines), approximately similar compressive strengths have been obtained by using CLS sand. On the other hand, CLC sand caused strength loss and increased the admixture demand for a targeted slump-flow of SCC. Due to the increased admixture content, setting times of SCCs prepared with CLC sand were also lengthened. The methylene blue adsorption value is a good indicator of clay content of sand. This test method was efficiently used for the selection of appropriate sand type incorporating high volumes of fine materials. Additionally, microstructural studies revealed some clues about the poor performance of SCCs prepared with CLC sand.

Mechanical Characteristics of Sands with Different Primary Properties

The mechanical behaviors of soils are remarkably influenced by their physical and chemical properties and by environmental factors. The physical properties are classified as primary and secondary categories; primary properties are permanent parameters of soil grains such as grain density, shape and size distribution, and secondary properties are non-permanent or changeable parameters of soil fabric. The long term objective of this study was to reveal the mechanical behavior of soils with different primary properties. The physical properties of sands with different primary parameters were investigated extensively. Some 200 granular materials including sands and a few artificial materials were prepared. The primary physical properties such as grain density, shape and size distribution of all samples were measured. Some index properties characterizing physical properties, such as maximum and minimum void ratios, crushability and angle of repose of sands, were also measured for all the samples. Based on the test results, the relationships between the primary properties and the index properties are discussed.

Effect of biofilm on the physical properties of sands contaminated with phenol

An experimental investigation was conducted to determine the relationship between biofilm thickness and the resulting decrease in porosity and permeability of local sands. Media tested consisted of two sizes of sands (0.2 and 0.3 mm). The study was carried out in three phases with respect to influent phenol concentrations. The modified Kozeni‐Carman equation was used to estimate the thickness of biological film, knowing the biofilm‐affected permeability. The estimated values of the film thickness varied from 0.04 mm to 0.10 mm. Media porosity decreased between 29% and 51.3% in the sands with increased biofilm accumulation. A good correlation was observed between porosity and biofilm thickness in the range of low film thickness (0.066 mm ‐ 0.099 mm).

Physical Properties of Sand as Affected by Clinoptilolite Zeolite Particle Size and Quantity

Little is known about how the particle size of amendments influences the physical properties of amendment-sand mixtures. In two laboratory experiments, the amendment clinoptilolite zeolite (CZ) was used to amend sand at two sand:CZ ratios of 5 and 10 (w/w) and six CZ particle sizes, including: >1 mm, 1 to 0.5 mm, 0.5 to 0.25 mm, 0.25 to 0.105 mm, 0.105 to 0.047 mm and <0.047 mm. Saturated hydraulic conductivity (SHC) ranged from 3 to 48 cm hr¯¹, decreased with the decreasing CZ particle size which was most noticeable at the finest CZ particle size. The water content of CZ-sand mixtures at soil matric potentials from -3 kPa to - 10 kPa increased with decreasing CZ particle size. Bulk density of the CZ-sand mixtures (except for CZ-mixtures < 0.047 mm) ranged from 1.37 to 1.42 g cm¯³, which were significantly (p = 0.01) lowered than the unamended sand (1.48 g cm¯³) . Sand amended with 10% of the finest CZ particle size had the lowest total porosity (41.5 g Kg¯²). Aeration porosity (at -3 kPa soil matric pote...

Mechanical and physical properties of sands in the middle reach of the Parana River : Larangeira, D; Pardini de Corzo, M E Proc 5th International Congress International Association of Engineering Geology, Buenos Aires, 20–25 October 1986V2, P849–861. Publ Rotterdam: A A Balkema, 1986

Mechanical and physical properties of sands in the middle reach of the Parana River : Larangeira, D; Pardini de Corzo, M E Proc 5th International Congress International Association of Engineering Geology, Buenos Aires, 20–25 October 1986V2, P849–861. Publ Rotterdam: A A Balkema, 1986

Local variations of outdoor radon concentrations in the Netherlands and physical properties of sand with enhanced natural radioactivity

Time-averaged radon concentrations in the outside air in the Netherlands were found to be almost twice as high in the second half of the year as in the first half. Local variations of a factor of 4 occur over rather short distances. Islands in the North Sea have darker parts at their beaches where the gamma-ray activity is above normal. At these spots concentrations of heavy minerals were found. The average particle size of these minerals shows a linear relation with their density. The radioactivity is due to the incorporation of uranium thorium in the crystal lattices of these minerals. Concentration of these minerals elsewhere in the country may well lead to enhaanced outdoor radon concentrations.

Study on the physical properties of Sand by the Electrical Resistance

Study on the physical properties of Sand by the Electrical Resistance