Test for Silt and Clay Content - Lab Report Example

Sieve Analysis of Sand, Test for Silt and Clay Content, Test for Chloride Content Name: Experiment 6 Course: Lecturer: Institution: Date: Table of contents Abstract 3 Introduction and Objectives 3 Method 5 Results and Analysis 6 Graph analysis 7 Discussion 9 Conclusions 10 Reference 11 Abstract This experiment was to find out how the particles spread on the sample tested. These samples included measurement of the diffusion coefficients which are Uniformity coefficient Cu = 10.5, Effective size d10 = 190, Coefficient of gradation Ck = 0.66. From the test of the clayey silt tested different diffusion coefficients were recorded through the examination of the clay and silt used. In this experiment, the calculated error was about 0.4 %, which was relatively lower than the initial 0.7% mass value. This error compared to the allowable error 0.4% was relatively smaller, which is 0.7%. In essence, the error being 0.4% amounts for more accurate results as compared to the allowable 0.7% error value of the retained mass. From the recorded results it is one can see that, the experimental results and the model analysis have cogently proved that the transport theory of the solutes of the chloride is predictable. In these tests, the transport of the chlorides was dominated by diffusion in the experimental tests. Introduction and Objectives Transport behaviour of the migration in the soil layer is the basis for testing the contents of clay and silt in the soil sample. Ideally, construction aggregate is a very significant material. This is because the as a main component of concrete it uses 60 -75% volume. Therefore, concerning performance and long service of the aggregate, according to the ASTM C 136-04, 2004, this makes the material viable for construction purposes. Generally, the aggregate composition includes the crushed and uncrushed minerals such as granite, sandstone and limestone. Other minerals that are present in the aggregate include minerals that have lightweight in the construction and they include mica, pumice, and fabricated pulverised fuel ash. When properties such as workability, strength, density, thermal properties, and additional hardness of the minerals have been established they determine the basic properties of the concrete aggregate in use. The light weight stones that may used when testing the mineral content of the clay and silt may include pumice, mica, granulated ground blast furnace slag, man-made pulverised fuel ash or expanded clay to dense iron ore such as hematite (ACI 213R-03, ,2003). Other applications of the aggregate may include applications such as hardcore formation or used as fill material in the creation of bases to concrete foundations, floors, slabs and pavements. The major classification of aggregates may include natural or non-natural. This classification may depend on the source of the aggregate material as well as the method of preparing the aggregate. Majorly, natural sand and gravels are formed through the process of weathering and wind and water action by crushing the natural coarse stones. In addition, the formation of the gravels and the fine sand may be obtainable from the crushing of the coarse gravel by the high wind speeds as well as weathering process by water. It is necessary to crush the sand and the gravel that has been obtained for the quarries and other sand and stone deposits so that the screening and other analysis processes may be carried on. In analysing the sand used in silt and clay test, it is important to determine the coefficient of diffusion that each finite element has for each layer that is in use. For the purpose of production of the concrete production, Igneous, metamorphic or sedimentary rocks are ideal raw materials. However, the geology of the rock used does not make an aggregate superior. So when determining the aggregate to use, it is necessary to deal with the specifics of the information obtained in terms of the test that have been conducted so as to obtain the ideal results that are reliable. Majorly this test had two objectives; firstly, it was to determine the coefficients of diffusion of chloride in fine silt, sand and clay contents. Diffusion coefficients of the samples were measured to determine the grain size through particle size distribution or sieve analysis. The aggregate sample was also used to determine the distribution of the grain size, strength, as well as the workability of the grain size and the placement of the mix. In this test the ideal case showed that the range of particle size was as from the large to fine aggregates arrangement. This is as presented in the table below. PERCENTAGE BY MASS PASSING Coarse Percentage Medium Percentage Fine Percentage 5 to 45 30 to 70 55 to 100 Table 1: Coarseness or fineness based on the percentage passing the 5mm sieve (BS EN 12620:2002 Table B.1) Method British standard sieves were used in this test. The sieves in different sizes from the smaller one for the crashed particle to the aggregate sizes as follows; 10mm, 5mm, 2.36mm, 1.18mm, 600m, 300 m, and 150 mm. Steps used Step 1: I weighed 600g of dry sand. Step 2: I placed the sieves on a mechanical shaker in order of their size with the 10mm sieve being at the top and the 150mm size at the bottom. Step3: I then passed the sand successfully through the sieves starting with the largest size where the process involved shaking the nest of sieves for 15 minutes. Step 4: I then weighed the remaining material on the sieve to determine the weight of the retained materials. Step 5: I cleaned sieves out using an appropriate wire brush, where I brushed the aggregate back out of the sieve. Brushing the aggregate through the sieve was avoided as this could distort the sieve or result to the blockage of the sieve. Results and analysis Through the results obtained in the table below, it is clear that the 2.36mm sieve could not allow the 186g to passed instead it was retained on the sieve. In addition, the 2.36mm sieve retained 219.6g while the 5mm sieve could allow passage of a large number of the particles and only 32.2g was retained in this sieve. Therefore, the percentage of the retained particles on each sieve signified that different sizes of the particles that had been retained so that the results that were obtained could be use in the analyses of the silt and clay particles present in the mix. Considering other sieves, that is, the 10mm sieve no particles retained, implying that the particles were of lower size than the 100m sieve. Although the 5mm sieve allowed 94.64% of the particles to pass, it was observed that the particle retained was 32.3g, which was 5.36%, and this was the large particles that cannot be used as ideal for concrete construction. Table 2 BS Sieve Mass on sieve (g) (Column a) Cumulative mass retained (g) (Column b) % retained (column c) % passing (column d) 10.00 mm 0 0 0 100 SW 5.00 mm 32.2 32.2 5.36 94.64 2.36 mm 187.4 219.6 36.5 63.82 1.18 mm 112.8 332.4 55.3 44.7 600 m 79.6 411.8 68.5 31.5 300 m 79.6 491.4 81.7 18.3 150 m 67.4 558.8 93 7 Tray 44.6 603.4 100 0 Total of all sieves + tray 603.4 Data Analysis Table above clearly shows that 10% of the particles had a diameter of 190 µm. Thus, the smaller the size of the particles, the smaller the sample and this was indicated as d10. This size indicated the maximum size of the particles that gave the smallest size of the sample used, which was 10%. The value of d30 of the sample, which is the maximum size of the smallest 30% of the sample is 500m. Moreover, the d60 was the sample is maximum size of the smallest 60% of the sample is 2000m. This means that the particles that had about 2000m size in diameter was 60% of the sample used. Graph analysis From the above graph, grading characteristics of the sample of the particles used is obtainable from d10, d30 and d60 of the particle sizes. Therefore, the grading characteristics applicable include uniformity coefficient, the effective size, and the coefficient of gradation. Calculations Uniformity coefficient  Effective size  Coefficient of gradation    In the fineness modulus, the other characteristic of the particles is obtainable. This is possible through division of the total percentages of the coarser sizes by 100. Using the specified sieves 75.0, 37.5, 19.0, and 9.5 mm 4.75 mm, 2.36 mm, 1.18 mm, 600μm, 300 μm, and 150 μm Total percentage  Discussion For the single sized particles, the Cu and Ck are always equal to one. When the Cu value is less than three, it shows that that there is uniformity in the particle sizes while when the value is higher than five, it is indicates that that there is well aggregate grading. However, when the value of Ck is less than 0.1 it means that the graded particles give a mean gap (ACI 213R-03, 2003). The value of the obtained Cu (10.5) in this test indicates that the aggregate is well graded. Moreover, the value of the Ck obtained as 0.66 lies in the range of 0.5 and 2.0, which is an indication of a well-graded sample. The obtained value of the FM, which is 3.4 shows that the aggregate is slightly above the mark of fine aggregate classification, which means it is not fine and some refining is necessary. Therefore, the ideal aggregate should have FM of 2.3 to 3.1, to be classified as a fine aggregate. Due to losses that may occur during the process of sieving and analysis, there are cases of mass losses in samples used. Therefore, these losses account for the possibility of the reduced sample mass, which may account for the effect of the result of the FM obtained at the end of the analysis. As a result, the resultant errors in the calculations those are in question for the final analysis of the sample will be higher. Ideally, the expected difference of the mass expected should be less than 0.1% as per the number of the mass determinations. The allowed maximum error for this test should be at most 0.7% of the original mass, therefore using the original mass of 601g compared to the total mass of particles retained that was 603.4g it gave an error difference of 2.4g. This error amounted for only 0.4% of the original mass, which less than the allowed error for this test and thus the error was less than expected making the results obtained ideal and quantifiable Conclusions The coefficient of diffusion of the chloride in the clay alongside the silt and the sand used indicated the saturation rates in the samples. Therefore, the obtained coefficients of the chloride in the compacted clay should the saturation of the silt and the sand, which had saturation coefficients of 72% and 52% respectively. The diffusion contents of the chloride and the diffusion rates that were obtained for the corresponding clay and silt used was ideal as per the soil used in the test in determination of the chloride content in the samples given. However, in the test particles were well graded well graded from the sense that the test was carried out suitably as the difference in the total mass retained and the original mass was within the range of 0.7%, which is the maximum allowed error for this test. References ASTM C 136-04, (2004) "Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates." ASTM C 702-98(2003), "Standard Practice for Reducing Samples of Aggregate to Testing Size." ACI 213R-03, (2003) "Guide for Structural Lightweight Aggregate Concrete," American Concrete Institute, Mich.Farmington Hills, Read More

It is necessary to crush the sand and the gravel that has been obtained for the quarries and other sand and stone deposits so that the screening and other analysis processes may be carried on. In analysing the sand used in silt and clay test, it is important to determine the coefficient of diffusion that each finite element has for each layer that is in use. For the purpose of production of the concrete production, Igneous, metamorphic or sedimentary rocks are ideal raw materials. However, the geology of the rock used does not make an aggregate superior.

So when determining the aggregate to use, it is necessary to deal with the specifics of the information obtained in terms of the test that have been conducted so as to obtain the ideal results that are reliable. Majorly this test had two objectives; firstly, it was to determine the coefficients of diffusion of chloride in fine silt, sand and clay contents. Diffusion coefficients of the samples were measured to determine the grain size through particle size distribution or sieve analysis. The aggregate sample was also used to determine the distribution of the grain size, strength, as well as the workability of the grain size and the placement of the mix.

In this test the ideal case showed that the range of particle size was as from the large to fine aggregates arrangement. This is as presented in the table below. PERCENTAGE BY MASS PASSING Coarse Percentage Medium Percentage Fine Percentage 5 to 45 30 to 70 55 to 100 Table 1: Coarseness or fineness based on the percentage passing the 5mm sieve (BS EN 12620:2002 Table B.1) Method British standard sieves were used in this test. The sieves in different sizes from the smaller one for the crashed particle to the aggregate sizes as follows; 10mm, 5mm, 2.36mm, 1.18mm, 600m, 300 m, and 150 mm.

Steps used Step 1: I weighed 600g of dry sand. Step 2: I placed the sieves on a mechanical shaker in order of their size with the 10mm sieve being at the top and the 150mm size at the bottom. Step3: I then passed the sand successfully through the sieves starting with the largest size where the process involved shaking the nest of sieves for 15 minutes. Step 4: I then weighed the remaining material on the sieve to determine the weight of the retained materials. Step 5: I cleaned sieves out using an appropriate wire brush, where I brushed the aggregate back out of the sieve.

Brushing the aggregate through the sieve was avoided as this could distort the sieve or result to the blockage of the sieve. Results and analysis Through the results obtained in the table below, it is clear that the 2.36mm sieve could not allow the 186g to passed instead it was retained on the sieve. In addition, the 2.36mm sieve retained 219.6g while the 5mm sieve could allow passage of a large number of the particles and only 32.2g was retained in this sieve. Therefore, the percentage of the retained particles on each sieve signified that different sizes of the particles that had been retained so that the results that were obtained could be use in the analyses of the silt and clay particles present in the mix.

Considering other sieves, that is, the 10mm sieve no particles retained, implying that the particles were of lower size than the 100m sieve. Although the 5mm sieve allowed 94.64% of the particles to pass, it was observed that the particle retained was 32.3g, which was 5.36%, and this was the large particles that cannot be used as ideal for concrete construction. Table 2 BS Sieve Mass on sieve (g) (Column a) Cumulative mass retained (g) (Column b) % retained (column c) % passing (column d) 10.

00 mm 0 0 0 100 SW 5.00 mm 32.2 32.2 5.36 94.64 2.36 mm 187.4 219.6 36.5 63.82 1.18 mm 112.8 332.4 55.3 44.7 600 m 79.6 411.8 68.5 31.5 300 m 79.6 491.4 81.7 18.3 150 m 67.4 558.8 93 7 Tray 44.6 603.4 100 0 Total of all sieves + tray 603.4 Data Analysis Table above clearly shows that 10% of the particles had a diameter of 190 µm. Thus, the smaller the size of the particles, the smaller the sample and this was indicated as d10.

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