I want you to paraphrase this discussion Discussion: This test is performed for

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I want you to paraphrase this discussion

Discussion:

               This test is performed for a variety of reasons. Firstly, in this report, the sieve analysis was performed to see if a soil is suitable for use in concrete as outlined in MTO standards. This test may also be performed for a relatively simple indication as to the performance of a soil as an engineering material in a variety of different functions. Knowing the grade of a soil may allow an engineer to predict how the soil will perform as a drainage material, how a soil will respond to the load of a foundation upon it, the susceptibility of a soil to deform from the action of frost, its potential to swell with the introduction of water, and even its ability to passively filter water that passes through it.

               Although this test used a large stack of sieves to give a rather fine approximation of the grade of the soil as it passed through many incrementally finer openings, certain properties of a soil may be determined with a much smaller stack of sieves. Under the Unified Soil Classification system, for instance, only two sieves (the No. 4 and the No. 200 sieves) are required to differentiate a soil between gravels, sands, and silts or clays. Immediately, a field engineer would have some insight into the soils drainage capacity and ability to provide filtration. The stack of sieves employed in this test is required, however, to fully classify since both the Coefficient of Uniformity and the Coefficient of Concavity require an insight into intermediate particle sizes between these the No. 4 and No. 200 sieves and the rate of change in particle sizes between them.

               Several sources of error are associated with this test. Firstly, some amount of soil may be lost as the test is conducted. This could be a result of fine particles not settling after the agitation portion of the test, fine particles being lost as the sample is transferred to the weighing dish from the sieve, or particles of any size being lodged in the mesh of the sieve. It is impossible to predict what size of particles would have been lost in these ways, but it is likely that finer particles would have been lost. As such, there would be a higher content of silts in the actual soil than what is indicated by these results. Furthermore, the sieves used in this particular test were damaged by improper handling before this test was conducted. The soil was not washed during the sieve analysis, this too would contribute to a higher content of silts in the soil than what is indicated by the results in this report. Finally, there is an inherent error with the accuracy of the balance, likely a loss of sensitivity, which would become apparent as the sample is divided into smaller portions after the sieve analysis compared to what was initially weighed before the test was performed. Fortunately, however, only 0.6% of the mass is unaccounted for. Aside from the decision not to wash the sample, whatever errors associated with this test do not significantly impact the validity of the results obtained.

Explanation / Answer

The report indicates that, Sieve analysis was done to measure the performance of the soil in many ways to see the soil fitment as indicated in the MTO standards. Soil’s different function will be measured to know the quality of the soil which can perform as a drainage material, how the soil can react to the load foundation, soil’s reaction to the introduction to water, Exposure of soil to deform the action of frost.

Even though this used involves a large amount of filters used to find the finest quality of the soil, certain set of soil requires less amount quality checks. According to the soil classification system only 2 varieties (NO 4 & No 200) are required to differentiate between the soil’s gravels, sands & silts. Once the test is done the field engineer would know the capacity of the soil’s drainage capacity and the capability of providing filtration. To fully classify the uniformity and concavity of the soil an indepth insight is required to check the rate of change in particles for No 4 and No 200

There are many opportunities for error in these kind of tests. Some part of soil will be lost during the test and some particles               does not settle post the soil test is done. The fine particles of the soil may lost as the samples gets transferred to weighing from the testing machine. There is no way possible to determine what kind of particle is lost in the transit but the only thing can be made sure of is its finest particle. As a result of the test there will be a lot of residuals post the soil test and soil would not have been washed which leads to more contents of silts in the soil. However post the test it leads to imbalanced accuracy & loss of sensitivity. Only 0.6% is unaccounted. Apart from the soil washing any other error would not really impact the result achieved.

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