Sand Gradation Research Articles

Prediction of cement suspension groutability based on sand hydraulic conductivity

The experimental investigation reported herein aims toward the development of groutability prediction models based on the hydraulic conductivity of sand and other parameters affecting the groutability of cement suspensions. For the purposes of the present study, suspensions of three different cement types, each at four different gradations, having water to cement (W/C) ratios of 1, 2 and 3, by weight, were injected into dry and dense sand columns with a height of 36.5 cm. The tested cements cover the range from ordinary to microfine materials having nominal maximum grain sizes of 100, 40, 20 and 10 μm. Six uniform, clean sands with different grain sizes were used alone or mixed in various proportions to obtain 48 additional sands, with different gradations, for grouting. Suspension groutability is improved by increasing cement fineness and suspension W/C ratio or by decreasing apparent viscosity and is controlled by the hydraulic conductivity and the gradation of the sand. The groutability and filtration limits defined in the present study, are based on sand hydraulic conductivity and suspension apparent viscosity and depend on cement fineness and sand gradation. The best model developed by performing Binary Logistic Regression analyses of the injection test results is regarded as an efficient tool for the prediction of groutability of cement suspensions in sands with different gradations, as it exhibits a coefficient of multiple determination equal to 0.914 and estimates successfully the outcome of the injection tests available from this study and collected from other studies at a rate equal to 89% and 70.5%, respectively.

Effects of Particle Gradation, Relative Density and Curing on the Strength of Silicate Grouted Sand

This research paper presented the influence of variables such as sand gradation, relative density, curing time and condition and sodium silicate content on the strength characteristics of sodium silicate-formamide injected sand. To start with, the viscosity, gel time, and syneresis of sodium silicate-formamide grouts were studied. With the increase of sodium silicate content in the grout mix, the setting time of sodium silicate-formamide solutions decreased but the viscosity increased. Additionally, an increase in silicate content increased the amount of syneresis of grouts up to a specific point. The grouts with various silicate contents successfully penetrated the sand specimens with different grain size distributions and relative densities. The wet-cured and the air-dried samples were subjected to unconfined compressive (UC) and undrained-unconsolidated (UU) triaxial tests at various time intervals. The UC strengths of wet-cured as well as the air-dried specimens varied from 0.11 to 0.80 MPa and from 0.48 to 2.52 MPa respectively at the end of the 150th day. Moreover, as the internal friction angles of wet-cured and air-dried specimens ranged from 36° to 43° and from 41° to 50° the cohesion intercepts of wet-cured and air-dried specimens varied from 40.78 to 161.68 kPa and from 85.84 to 348.62 kPa respectively at the end of 150th day. As the silicate content of grouts increased, UC and UU strengths of air-dried and wet-cured samples increased. The UC and UU strengths of injected sand specimens under wet-cured condition reduced with time owing to syneresis. However, the UC and UU strengths of grouted specimens under air-dried condition increased with time. Though the strength of grouted sand samples was slightly increased with the increase of relative density, it was found to be highly variable with the grain size distribution.

Co-transport of chromium(VI) and bentonite colloidal particles in water-saturated porous media: Effect of colloid concentration, sand gradation, and flow velocity

The transport of pollutants inside the groundwater system is profoundly affected by absorption and transmission via colloid or soil particles. Therefore, it is essential to investigate the significant pollutants (Such as hexavalent chromium (Cr(VI))) transfer in the presence of colloid particles that can facilitate or retain this transfer. For this purpose, an experiment is carried out in a saturated porous media column to study the bentonite concentration, flow velocity and sand grain size effects on co-transport of Cr(VI) with bentonite. The results of this study demonstrated that the colloid particles facilitate the transfer of Cr(VI) by 30% in 200 mg/l bentonite colloids concentration. The amount of transmitted Cr(VI) is decreased by increasing the bentonite colloids concentration from 200 mg/l to 300 mg/l. As the flow velocity increased from 2 cm/min to 3.3 cm/min, the amount of transferred Cr(VI) increased by 7%. The results show that with reducing the sand grain size, the amount of transmitted bentonite and Cr(VI) is reduced that this effect is more sensible in bentonite transport. As a result, it can be noted that the bentonite colloidal particles according to its concentration and experimental conditions, may facilitate or retain the Cr(VI) transport and sand gradation has a significant impact on colloid and pollutant transmission.

Innovation of Sustainable and Greener Raised Median or Road Divider on Expressway

This study purposes a new innovation design for the construction of road divider that more sustainable and greener which is eco-friendly. It was conducted to modify the material used on the road divider, so that the suitability of the material can reduce the impact of the vehicle during road accident. Objective of this study is to test and design greener sustainable materials as a road median component. Besides, the study is to determine the suitability and characteristics of materials for road median. Materials used in this study are gunny sacks filled with sand, laterite soil, soft turfing (cow and pearl grass) and used tire as a cushion effect. Based on experiment testing, sieve analysis result showed that river sand is a good grade sand and suitable for road median. While, direct shear test showed sand and soil used for this study are suitable because there have a high shear strength. For grass observation, cow grass is suitable compare pearl grass in term of growth rate, maintenance cost, durability on sunlight exposure and weather in Malaysia. The load applied for conducting impact test on the sand sack were 14.08N 25.6N 44.8N. The initial damage occurred when a force reaches at 44.8N. However, the condition of the arrangement of sand sack is still stable. In conclusion, this new innovation of green and sustainable road divider has high potential in absorbing the impact of accidents.

Eco-efficient earth plasters: The effect of sand grading and additions on fresh and mechanical properties

Earth-based plasters can be very eco-efficient both in terms of embodied energy and technical efficiency, although they are vulnerable to water when unstabilized. An experimental campaign was developed to assess the workability and the mechanical properties of formulated earth-based plastering mortars with a 1:3 (illitic clayish earth:aggregate) volumetric ratio. The aggregate components include different proportions of coarse and fine siliceous sands and the partial replacement of fine sand by a phase change material (PCM) or the addition of a low content of oat fibers. A pre-mixed earth mortar produced with clayish earth picked from the same pit was assessed as control. Mortars were tested to evaluate workability and density in the fresh state, and results were compared to dry bulk density, dynamic modulus of elasticity, flexural, compressive and adhesive strengths and dry abrasion resistance. Results show that even 15% replacement of the fine sand by the PCM significantly changes the workability, apart from decreasing the shrinkage and dry bulk density and reducing the mechanical strength of the mortars. Therefore, the addition of this type of PCM, that most probably have advantages in terms of thermal behavior of the plasters, may have important drawbacks in the fresh and hardened state of earth plasters that should also be considered. The addition of oat fibers does not show any improvement on the workability and mechanical characteristics of the earth mortars. In these mixed sand mortars, higher coarse sand content promotes a decrease in mechanical performance, showing the advantage of using sand with a well graded particle size distribution.

Influence of particle-size disparity on cyclic liquefaction resistance of silty sands

Liquefaction of silty sands remains puzzling due to the complexity involved in the interaction between coarse and fine particles during loading. This paper presents first-hand experimental data from a series of cyclic triaxial tests under controlled particle characteristics, with the aim to elucidate the influence of particle-size disparity on the liquefaction resistance of sand−fines mixtures. A detailed analysis of the test results and an experimental database compiled from the literature reveal that the particle-size disparity, defined as the ratio between the characteristic sizes of the base sand and the fines, is a major and rational factor controlling the reduction of cyclic resistance of sand−fines mixtures as compared with factors such as the grading and shape of the base sand. A simple, explicit expression is further proposed to properly account for the reduction of cyclic resistance of sand due to fines.

Assessment of Actual and Predicted Hydraulic Conductivity of various Gradations of Natural Sand

Assessment of Actual and Predicted Hydraulic Conductivity of various Gradations of Natural Sand

Effect the silica sand percentage as subtitution of fine agregate on the concrete compressive strength

This study uses silica sand, which has a high SiO2 content and micron size as a substitute for normal sand with control specimens with compressive strength of fc ′ 45 MPa. Two types of silica sand gradations were used, namely 80-100 mesh(0.177 mm – 0.149 mm) in size and 325 mesh (0.044 mm) in size from Bangka as the fine aggregate. There were 45 cylindrical specimens sized 15 cm in diameter, 30 cm in height, and age of7, 14, and 28 days. The tests carried out were absorption test and compressive strength test based on SNI 1974: 2011, which explained the testing method of the compressive strength of concrete with cylindrical specimens. Based on the test results, the optimum compressive strength was 53.07 MPa in the specimen with a composition of 50% sized 80-100 mesh (0.177 mm – 0.149 mm) (+) 50% sized 325 mesh (0.044 mm) silica sand, which can increase 4.12% of the compressive strength from normal concrete. On the other hand, the lowest compressive strength was obtained in a specimen with a composition of 25% sized 80-100 mesh (0.177 mm – 0.149 mm) (+) 25% size325 mesh (0.044 mm) silica sand, which was 48.43 MPa at 28 days.

Physical Characterization and Optimization of Fineness Moduli of Natural Sand from The North Region of Cameroon Used in Construction

This paper deals with the physical characterization and the optimization of fineness moduli of some natural sand samples for their appropriate valorization in construction in North Cameroon. Five sands samples (SN5, SB1, SB2, SB3 and SB4) were selected from various locations. Tests conducted include Particle size analysis, Organic impurities, Sand Equivalent and Bulk density. Fineness Modulus (FM), Mean grain, Sorting index (Si), Skewedness index and Uniformity coefficient have been deducted mathematically. Results shown that the particle size distribution curves of the studied sands have an "S" shape. The sand equivalent values vary between 91.1 and 96.8 %, characteristic of very clean sand. The fineness moduli values vary between 1.9 and 3.4 except for samples SB1 and SB2 which are coarser with values of 3.4 and 3.3 respectively. Others results shown that all the sands are pure (impurity level less than 0.5 %), well classified Sorting index Si  0.35) and Coefficient of uniformity (Cu  2). Studied sands are globally coarse (skewedness index between -0.35 at -0.79). Only SB4 and SN5 satisfy the NF EN 933-1 gradation limits. Combinations of SB3 (FM = 2.1) with SB1 (FM =3.4) or SB2 (FM= 3.3) were carried out to get desired sand gradation (2.2 to 2.8), SB4 and SN5 having already good fineness moduli of 2.6 and 2.8 respectively.

Kuat Tekan dan Kuat Tarik Mortar sebagai Bahan Graut dengan Faktor Air Semen Optimum

Grout works as a binding agents of wall construction, paste parts on precast concrete, a filler on concrete or crack also sealing a conctrete join. The purpose of this study is knowing optimum concrete grout composition. Grout strength hopefully can fulfill compression and tension strength needed, fulfill slashyness requirements, no bleeding and no segregration. Research began with preliminary test of mortar composition charasteristics. Most of fine aggregate composition using sand with slightly fine sand gradation. The mortar slashyness test using mortar flow and funnel test that flow time of mortar used as slashyness rate. Next tests are compression and tension test of mortars. The variation of mortars composition are using cement : sand ratio in the amount of 1:0,5; 1:1; 1:1,5 and 1:2. The result from each mix with optimum W/C Ratio for the compression strength test in the amount of 1:0,5; 1:1; 1:1,5 and 1:2 consecutively are 45,518 MPa; 37,875 MPa; 34,673 and 28,202 MPa. For the tension strength test are 3,054 MPa; 3,314 MPa; 3,498 Mpa and 1,791 MPa.

About calcium carbonate precipitation on sand biocementation

The contribution of indigenous bacteria and of some possible precipitation due to chemical reactions occurring during the treatment of sandy soils through microbially induced calcite precipitation (MICP) is investigated in this paper considering two different grading size distributions. This is a novelty, because the presence of the feeding solution alone in the soil (usually used as control test, and named here as CICP) is usually not quantified as it is assumed that the total amount of calcium carbonate is formed only due to ureolytic activity of the bacteria added to soils. However precipitation can occur because bacteria naturally exist in soils and also, even if less likely, due to CO2 sequestration in a process called chilled ammonia process. The justification is because the ions necessary for forming calcium carbonate, both by the indigenous bacteria or by CO2 sequestration are supplied in the feeding solution (solution with urea, ammonium and a calcium source). Experimental tests were performed on a set of sand samples subjected to biological treatment using bacteria and another set exposed to chemical treatment using only the feeding solution, after checking that natural bacteria present in the soil would not interfere with the process. The samples were prepared with similar dry density. They were analysed through mercury intrusion porosimetry tests, chemical analysis and unconfined compression strength tests performed after partially drying the samples. Although the hydrolysis of urea made by the added bacteria speeds up the precipitation of calcium carbonate, the results showed that CICP appears to be independent from sand grading size distribution and introduces significant strength increment. For this reason, the treatment will have effect even if the bacteria added die. Nevertheless, it is important to promote adequate conditions for these bacteria to survive because higher strength values were measured in the samples where MICP treatment was done, and therefore the effectiveness of the technique increases in significant manner.

Improving Compressive Strength of Cement Concrete Mix by Using M-Sand and Bamboo Fiber

In the current world, concrete has become a very important part of the construction industry and the materials which are used in making concrete have evolved due to better quality of cement and better grade of coarse aggregates. The sand is an important part of concrete. It is mainly procured from natural sources. Thus the grade of sand is not under our control. The concrete cubes of M-20, M-25 & M-30 grade were threw in this trial explore work and tried to analyze different properties of concrete like compressive quality, workability. In this study M-sand is considered as a replacement of natural sand by 50, 70 & 90% by weight of sand in concrete design mix with 1% Bamboo fiber streams as an admixture. This study is carried out at the age of 7 and 28 days. In this work, the general properties of fresh and hardened concrete were tried and the outcomes were dissected. As concrete is a central material for the construction industry. In any case, in the present period where development is expanding quickly and development rate is coming to their statures, it is contrarily affecting our condition as well. So it is vital to utilize some optional materials as a part of concrete to minimize the cost, and to enhance the properties of concrete for better stability of the structures.

Influence of Various Sand Gradation on Mechanical Properties and Concrete Quality of High Performance Concrete (HPC)

High Performance Concrete (HPC) has a few characteristics: high strength, high early strength, high modulus of elasticity, high durability and long life in severe environments, low permeability and diffusion, resistance to chemical attack, toughness and impact resistance and so on. Almost 70 to 80% of the volume of the concrete is occupied by aggregate which have a great impact on characteristics and properties of a concrete. Not only course aggregate but fine aggregate also contributes a lot toward the performance of HPC. Thus, this research studied on the influence of various sand gradations on mechanical properties and concrete quality of HPC. The sand gradation utilized in the study are normal size sand, sand passing through sieve size 1180µm, sand passing through sieve size 600µm and sand passing through sieve size 300µm. The mechanical properties of HPC being studied are compressive strength and splitting tensile strength while the concrete quality of HPC is determined by using water absorption and Ultrasonic Pulse Velocity (UPV) test. The results show that the mechanical properties and concrete quality increased as the size of sand particles decreased. The optimum sand gradation is the sand passing through sieve size 300µm which achieved highest mechanical properties and concrete quality showing the highest result of compressive strength (123.9MPa), splitting tensile strength (8.91N/mm2), lowest percentage of water absorption (0.55%) and highest UPV value (7743N/mm2).

A centrifuge investigation of the relationship between the vertical response of footings on sand and CPT end resistance

This paper presents results from a systematic investigation of footing response in four different types of sands placed and tested under controlled conditions in a geotechnical centrifuge. A parallel series of cone penetration tests (CPTs) was performed to examine correlations between CPT end resistance (qc) and footing bearing pressure (q). The experimental results show that there is a unique relationship between the normalised bearing stress (q/qc) and the settlement normalised by footing diameter (s/B), irrespective of footing diameter, stress level, sand grading, mineralogy and angularity. These results are shown to compare well with findings from published databases of field-scale footing tests when allowance is made for the significant effects of creep. The study enables simple and robust recommendations to be established for the ultimate capacity (defined at s/B = 0·1) and allowable bearing pressure of a footing on sand.

Optimization of Grading of Sand in Backfill Using Metallurgical Waste

Optimization of Grading of Sand in Backfill Using Metallurgical Waste

Characterization of a sustainable mortar based on mineral additions and prepared sand

The present study is to investigate the physical and mechanical properties of the prepared sand mortars, mainly based on the local Oued Souf sand region south of Algeria, this in accordance with standard sand grading. The principal aim of the research is to replace the restricted fine part between (0.08and 0.16 mm) which is of the order 15% and to substitute it with additions active slag (S) and inert glass powder(GP) with dosages of 5, 10 and 15 % and maintain the rest of the granular fractions of the sand studied fixed. Thus, to see and analyze the influence of these additions on the physical properties and in regards the mechanical performances of confected prepared sand mortars. The results showed the advantageous effect of replacing the said prepared sand with two additions (slag and glass powder) on physical, mechanical properties mortars based on this local sand by improving the performance of these cement products, especially at an optimal percentage of 10%.

Experimental study on filter media using locally available materials in bioretention

Abstract Bioretention systems and selection of effective filter media are very important in implementation of sponge cities. The current study was carried out to find proper composition of filter media using locally available materials, which acclimate to the special/local climate, environmental and geographical conditions in Yangtze River Delta region. Results revealed that sand with discontinuous gradation and containing a certain amount of clay led to unsatisfactory hydraulic performance (hydraulic conductivity ranged from 423 mm/h to 1,054 mm/h, and 1,500 mm/h to 29 mm/h). In contrast, a mixture of locally available sand, which consisted of continuous gradation of coarse sand (40–70%, by mass), fine sand (0–40%, by mass), very fine sand (10–60%, by mass) and nutrient soil (0–3%, by mass), had a hydraulic conductivity ranging from 200 to 400 mm/h and relatively stable structure. During the 70 days' flooding test, the hydraulic conductivity changed in the first 20 days due to the migration of particles (mainly <0.6 mm) and then became stable; the stable value was close to the initial. Moreover, easy access and simple production processes made it easier to promote. Findings could be used as a guideline for implementation of bioretention systems and selection of locally available and effective filter material.

Bearing Capacity Analysis of Bridge Foundation Based on Cone Penetration Test Data and Soil Parameters Data

One that deserves the attention of planners in designing a bridge structure is the design of the substructure. This is due to the fact that the structure below determines the quality and service life of a bridge and at present many cases of bridge structure failures are caused by failures of the substructure in holding the load acting on the bridge The aim of this research to test the characteristics of the soil and calculate bearing capacity of the foundation based cone penetration testing data and soil parameters at the Aifa bridge construction field in Fafurwar District, Teluk Bintuni Regency, West Papua Province. From the results of testing the soil characteristics in the laboratory, the type of soil at point 1 is the type of good to bad graded sand soil (SW-SP) with a water content of 17.72%, specific gravity 2.98, liquid limit (LL) = 16,746% included in the non-plastic category. While the location of point 2 is obtained from good to bad graded sand soil type (SW-SP) with a water content of 28.52%, specific gravity 2.73, liquid limit (LL) = 16.746% including the non-plastic category. To analysis of the calculation of the bearing capacity of the foundation Aifa bridge using data from the sondir test results for point 1 was obtained allowable bearing capacity (Qall) is 4.610,44 kN and for point 2 was obtained allowable bearing capacity (Qall) is 3.598,43 kN. For calculating bearing capacity of the foundation using soil parameter data for point 1 was obtained bearing capacity allowable (Qall) is 2.209,93 kN and for point 2 was obtained allowable bearing capacity (Qall) is 655,41 kN

KAJIAN BAHAN TAMBAH ATERNATIF SERAT ECENG GONDOK TERHADAP CAMPURAN LATASIR SAND SHEET KELAS A SPESIFIKASI SEKSI-6 2010 BINA MARGA

Asphalt sand layer (Latasir) is a layer of road construction consisting of coarse aggregates, fine aggregates, fillers and hard asphalt, which are mixed, spread, and compacted in hot conditions at certain temperatures. In this study is the use of water hyacinth fiber in a mixture of thin layer sand sheet sand grade grade A. The purpose of this study was to determine the process of making test specimens with ingredients added to water hyacinth fiber and the process of testing specimens with ingredients added to water hyacinth fiber. The test was carried out by adding water hyacinth fibers in the sand sheet class A latasir mixture. And with the addition of water hyacinth fiber variations of 0.6%, 0.9%, 1.2% taken from asphalt content. The final result of this research was Marshall evaluation which was obtained for the effect of the addition of water hyacinth cellulose fiber in this study showed an increase in Marshall stability value of 27.29% with a mixture of 1.2% water hyacinth, plastic fatigue (Flow) decreased by -23 , 89% with a mixture of 0.9% water hyacinth, cavity filled in the mixture (Void in the Mix) increased by 18.65% with a mixture of 1.2% water hyacinth, cavity filled with asphalt (Void Filled With Asphalt) decreased by -8.74% with a mixture of 1.2% water hyacinth, cavity in aggregate (Void In Mineral Aggregate) increased by 7.80% with a mixture of 1.2% water hyacinth, and Marshall Quotient increased by 71.78% with a mixture of 0.9% water hyacinth. These results indicate that water hyacinth fiber can be used as an ingredient to add a mixture of latasir sand sheet class A specifications of clan development. Keywords: sand sheet class A sandflies, Marshall Test Index, water hyacinth fiber, stability, flow, Marshall Quotient.

Comparison study of beach geometrics and beach sand gradation related to abrasion potential based along the West Sumatra Province

The West Sumatra beach is very beautiful and has much diversity in terms of their natural properties. This paper elaborating the diversity of the West Sumatra Beach related to their abrasion potential. Field investigation conducted to collect the nature diversities such as the plantation, sands and the geometric. The sand samples have been taken from beaches and brought to the laboratory to investigate their physical properties. The geometric of the beaches were analysed to gain the specific parameter which are comparable each other. The special study on the role of vegetation on abrasion protection as well as numerical modelling of their mechanism also had been studied and reviewed in this study. Those diversities then are turned into the engineering parameter and linked each other to gain their relation to abrasion potential. This study than can redraw the relation between the physical soil properties as well as the beach geometric with the abrasion potential of the beaches. The plantations on the beaches also gave a good correlation to the abrasion problems. The study can give better understanding between the beach abrasion problems with their nature of geology and biology as well as human activities. This study then suggested that to protect the beach abrasion it is necessary to investigate many things including many fields such as engineering, coastal, geology, biology as well as social science.