Paraphrasing my lap report , writing homework help

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I have this lao report that i submitted nd had 100 plagiarism cuz i think i used my friend lap from previous semester as well as it shows that I used things from google. I need it to be paraphrased really well asap cuz I have only one more attempt !

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Liquid Limit and Plastic Limit Test Group: C LIQUID LIMIT TEST INTRODUCTION: The liquid limit of a soil is the moisture content, expressed as a percentage of the weight of the oven-dried soil, at the boundary between the liquid and plastic states of consistency. The moisture content at this boundary is arbitrarily defined as the water content at which two halves of a soil cake will flow together, for a distance of ½ in. (12.7 mm) along the bottom of a groove of standard dimensions separating the two halves, when the cup of a standard liquid limit apparatus is dropped 25 times from a height of 0.3937 in. (10 mm) at the rate of two drops/second. APPARATUS: 1. Porcelain evaporating dishes or similar mixing dishes approximately 4½ in. (114 mm) in diameter. 2. Pulverizing apparatus - mortar and rubber-covered pestle. 3. U.S. No. 40 (0.425 mm) sieve. 4. Spatula, about 3 in. (75 mm) long and approximately ¾ in. (19 mm) wide. 5. Balance sensitive to 0.01 g. 6. Watering bottle, with distilled, demineralized or tap water. 7. Drying tares with covers, such as metal cans with lids, which will prevent moisture loss. The tares and covers should be marked and weighed as matched pairs. 8. Mechanical Liquid Limit Device(s) • Manually operated - consisting of a brass cup and carriage, constructed according to the plan. • Electrically operated - a motorized device equipped to produce the rise and rate of drops of the brass cup. The device shall be calibrated to give the same liquid limit value as obtained with the manually operated device. 9. Grooving Tool and Gauge 10. Oven - a thermostatically controlled drying oven capable of maintaining temperatures of 230±9° F (110±5° C). 11. Desiccator - a container, usually of glass, fitted with an airtight cover, and containing at the bottom a desiccating agent such as calcium chloride. The device prevents the sample from absorbing moisture from the air while being cooled for weighing. PREPARATION OF TEST SAMPLE 1. It is preferable that soils used for liquid limit determination be in their natural or moist state, because drying may alter the natural characteristics of some soils. Organic soils in particular undergo changes as a result of oven-drying or even extended air-drying. Other soils containing clay may agglomerate, lose absorbed water which is not completely regained on rewetting, or be subject to some chemical change. 2. If it is determined that the soil is organic or fine-grained, containing no plus No. 40 (0.425 mm) material, the liquid limit shall be run on the sample in its natural state. 3. If the soil contains sand or larger size particles, provision must be made to separate the minus No. 40 (0.425 mm) material for testing despite the possibility that drying may alter the characteristics of some soils. The fine fraction of granular soil is normally free of organic matter or contains a minimal amount which does not affect the liquid and plastic limit results. 4. The soil shall be thoroughly dried in an oven at a temperature not exceeding 230±9° F (110±5° C). The pulverizing apparatus and the No. 40 (0.425 mm) sieve shall then be utilized for separation of the minus No. 40 (0.425 mm) fraction. Care should be EB 15025 Page 6 of 16 exercised to insure that the pulverizing apparatus does not reduce the natural size of the individual grains. If the sample contains brittle particles, the pulverizing operation shall be done carefully and with just enough pressure to free the finer material adhering to the coarser particles. The ground soil shall then be separated into two fractions by means of the No. 40 (0.425 mm) sieve. The plus No. 40 (0.425 mm) component shall be reground as before. When repeated grinding produces only a minimal quantity of minus No. 40 (0.425 mm) soil, the material retained on the No. 40 (0.425 mm) sieve shall be discarded and further pulverization of this fraction should be suspended. 5. The material passing the No. 40 (0.425 mm) sieve obtained from the grinding and sieving operations described above shall be thoroughly mixed together and set aside for use in performing the physical tests. Approximately 0.3 lb. (150 g) would generally suffice for the liquid limit test. PROCEDURE: 1. If the soil is organic or fine-grained containing no plus No. 40 (0.425 mm) material, and is in its natural state, proceed without adding water. Chopping, stirring and kneading may be necessary to attain a uniform consistency. Then proceed as described in Sections 6.3 through 6.9 below. 2. The soil sample prepared under 4.3 shall be placed in an evaporating dish, covered, and cured, and then thoroughly mixed with the addition of distilled, demineralized or tap water by alternately and repeatedly stirring, cutting and kneading with a spatula. If needed, further additions of water shall be made in increments of 1 to 3 mL; each increment of water shall be thoroughly mixed with the soil. The cup of EB 15-025 Page 7 of 16 the liquid limit device should not be used for mixing soil and water. Add sufficient water to produce a consistency that will require 25 to 35 drops of the cup to cause closure. 3. A sufficient quantity of the soil mixture obtained shall be placed in the cup above the spot where the cup rests on the base and shall then be squeezed and spread into the position, with as few strokes of the spatula as possible. Care should be taken to prevent the entrapment of air bubbles within the mass. With the spatula, level the soil and at the same time trim it to a depth of 0.3937 in. (10 mm) at the point of maximum thickness. Return the excess soil to the evaporating dish. The soil in the cup shall be divided equally by a firm stroke of the grooving tool along the diameter through the centerline of the cam follower so that a clean, sharp groove of the proper dimensions will be formed. To avoid tearing of the sides of the groove or slipping of the soil cake on the cup, up to six strokes, from front to back, or from back to front counting as one stroke, shall be permitted. The depth of the groove should be increased with each stroke and only the last stroke should scrape the bottom of the cup. 4. Lift and drop the cup by turning the crank, F, at the rate of 2 rps, until the two halves of the sample flow together and come in contact at the bottom of the groove along a distance of ½ in. (12.7 mm). Record the number of drops (blows) required to close the groove this distance. A valid test is one in which 15 to 35 blows are required to close the groove. 5. A sample of the soil is now taken to determine its moisture content. Remove a slice of soil approximately the width of the spatula, extending from edge to edge of the soil cake at right angles to the groove and including that portion of the groove in which the soil flowed together. Place in a moisture tight tared container. Weigh to the nearest 0.01 g and record. 6.6 The soil remaining in the cup shall be transferred to the mixing dish. The cup and grooving tool shall then be washed and dried in preparation for the next trial. 6. The foregoing operations shall be repeated for at least two different determinations on the soil sample to which sufficient water has been added to change the soil to a fluid state, and then a more fluid state. The object of this procedure is to obtain samples of such consistency that at least one determination will be made in each of the following range of drops: 25-35, 20-30, 15-25, so the range in the three determinations is at least 10 drops. The number of drops required to close the groove should be above and below 25. 7. The test shall proceed from the drier to the wetter condition of the soil. However, when the soil in its natural state is of such consistency that closure occurs at less than 25 drops (sample wet), the process must be reversed so as to obtain determinations in each of the aforementioned range of drops. Drying of the soil shall be accomplished by a combination of air-drying and manipulation by kneading. In no case shall dried soil be added to the natural soil being tested. 8. Oven-dry all the soil samples in the tared, uncovered containers to constant weight at 230±9° F (110±5° C), place samples in a desiccator (1) and allow to cool. Replace the covers on the containers, and weigh before hygroscopic moisture can be absorbed. Weigh (2) to the nearest 0.01 g and record. The loss in weight of the soil in each tare, due to drying, is recorded as the weight of water. (1) A desiccator is used to cool the dried soil samples before weighing. The hot samples, if placed immediately on the balance, cause convection currents in the air which can cause serious weighing errors. Weigh within 15 minutes, at which time the samples should be cool. (2) Always weigh on the same balance previously used. CALCULATIONS Use Form SM 309 to record test data, which will include the number of blows for each trial run. Then calculate the moisture content of each sample of soil, expressed as a percentage of the weight of the oven-dried soil, as follows: Form SM 309 uses the International System of Units (g) for recording the small weights (tare, tare & wet soil, etc.). 𝑀𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝐶𝑜𝑛𝑡𝑒𝑛𝑡 = 𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟 𝑥 100 𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑜𝑣𝑒𝑛 𝑑𝑟𝑖𝑒𝑑 𝑠𝑜𝑖𝑙 Item Can no. Mass of can, M1 (g) Mass of can + moist soil, M2 (g) Mass of can + dry soil. M3 (g) Moisture content Number of blows 𝐿𝑖𝑞𝑢𝑖𝑑 𝐿𝑖𝑚𝑖𝑡 = 𝑊 𝑥 𝑁 0.121 25 𝑊1−𝑊2 𝐹𝑙𝑜𝑤 𝐼𝑛𝑑𝑒𝑥 = log 𝑁2−log 𝑁2 GRAPH: Test No. 1 2 15.9 15.8 3 15.94 46.59 48.13 41.9 35.98 52.84 38 36.75 54.32 23 32.36 58.10 17 = 55.26 = 6.792 GRAPH Moisture Content (%) 59.00 58.00 57.00 56.00 55.00 GRAPH 54.00 53.00 52.00 0 10 20 30 40 Number of Blows CONCLUSION: The Liquid Limit was able to be calculated and a graph of moisture content versus Number of blows is plotted to obtain a smooth curve as expected. Three different test specimens were tested and results for average of these values are taken to obtain the final solution and values for Liquid Limit and Flow Index. PLASTIC LIMIT Test INTRODUCTION The plastic limit of a soil is the moisture content, expressed as a percentage of the weight of the oven-dry soil, at the boundary between the plastic and semisolid states of consistency. It is the moisture content at which a soil will just begin to crumble when rolled into a thread ⅛ in. (3 mm) in diameter using a ground glass plate or other acceptable surface. APPARATUS 1. Evaporating dishes - porcelain or similar mixing dishes approximately 4½ in. (114 mm) in diameter. 2. Pulverizing apparatus - mortar and rubber covered pestle. 3. U.S. No. 40 (0.425 mm) sieve. 4. Spatula, about 3 in. (75 mm) long and approximately ¾ in. (19 mm) wide. 5. Balance sensitive to 0.01 g. 6. Watering bottle, with distilled water demineralized or tap water. 7. Drying tares with covers, such as metal cans with lids, which will prevent moisture loss. The tares and covers should be marked and weighed as matched pairs. 8. Surface for rolling - a ground glass plate or piece of glazed or unglazed paper on which to roll the soil sample. (Unglazed refers to paper similar to that used for mimeographing). Paper toweling is not satisfactory. 9. Oven - a thermostatically controlled drying oven capable of maintaining temperatures of 230±9° F (110±5° C) for drying moisture samples. 10. A ⅛ in. (3 mm) diameter rod may be used as a guide to help the operator estimate the thread size. 11. Desiccator. PROCEDURE 1. Squeeze and roll a 0.3 oz. (8 g) test sample into an ellipsoidal shaped mass. Roll this mass between the fingers or palm of hand and the ground glass plate or satisfactory paper on a smooth horizontal surface with just sufficient pressure to roll the mass into a thread of uniform diameter throughout its length. The rate of rolling should be between 80 and 90 strokes/min., counting a stroke as one complete motion of the hand forward and back to the starting position again. 2. When the diameter of the thread becomes ⅛ in. (3 mm), break the thread into six or eight pieces. Squeeze the pieces together between the thumbs and fingers into a uniform mass roughly ellipsoidal in shape, and reroll. 3. Continue this alternate rolling to a thread ⅛ in. (3 mm) in diameter, gathering together, kneading and rerolling, until the thread crumbles under the pressure required for rolling and the soil can no longer be rolled into a thread. 4. Crumbling may occur when the thread has a diameter greater than ⅛ in. (3 mm). This shall be considered a satisfactory end point, provided the soil has been previously rolled into a thread ⅛ in. (3 mm) in diameter. 5. The crumbling will manifest itself differently with various soil types: some soils fall apart in numerous small aggregations of particles; others may form an outside tubular layer that starts splitting at both ends. The splitting progresses toward the middle, and finally the thread falls apart in many small platy particles. Heavy clay soils require much pressure to deform the thread, particularly as they approach the plastic limit, and finally the thread breaks into a series of barrel shaped segments each about ¼ to ⅜ in. (6.3 to 9.5 mm) in length. 6. At no time shall the operator attempt to produce failure at exactly ⅛ in. (3 mm) diameter by allowing the thread to reach ⅛ in. (3 mm), then reducing the rate of rolling or the hand pressure or both, and continuing the rolling without further deformation until the thread falls apart. Maintain the same rate of rolling and the same hand pressure during the entire test. When testing very low plastic soils, it is permissible, however, to reduce the total amount of deformation by making the initial diameter of the mass near the required ⅛ in. (3 mm) final diameter. 7. When the plastic limit has been reached, a sample of the soil is immediately taken to determine its moisture content. Place the crumbled portions of the soil together in a suitable tared container. Weigh the container and wet soil and record on Form SM 309 (Appendices B & C). Weigh to the nearest 0.01 g. 8. Repeat above steps again to obtain another plastic limit sample. Weigh and record on Form SM 309. 5.9 Oven-dry the soil samples in the uncovered containers to constant weight at 230±9° F (110±5° C). Place samples in a desiccator (1) and allow to cool. Replace the covers on the containers and weigh before hygroscopic moisture can be absorbed. Weigh (2) to the nearest 0.01 g and record. The loss in weight of the soil in each tare, due to drying, is recorded as the weight of water. (1) A desiccator is used to cool the dried soil samples before weighing. The hot samples, if placed immediately on the balance, cause convection currents in the air which can cause serious weighing errors. Weigh within 15 minutes, at which time the samples should be cool. (2) Always weigh on the same balance previously used. CALCULATIONS Calculate the moisture content of each soil sample expressed as a percentage of the weight of the oven-dry soil, as follows: 𝑃𝑙𝑎𝑠𝑡𝑖𝑐 𝐿𝑖𝑚𝑖𝑡 = 𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟 𝑥 100 𝑤𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑜𝑣𝑒𝑛 𝑑𝑟𝑦 𝑠𝑜𝑖𝑙 The two moisture contents are averaged to obtain the plastic limit. If the test results vary appreciably, retest, because reproducibility of results is mandatory to obtain the correct plastic limit. Item Test No. Can no. 4 5 Mass of can, M1 (g) 15.82 15.9 17.58 17.23 (g) 17.21 16.94 Plastic Limit 26.62 27.88 Mass of can + moist soil, M2 (g) Mass of can + dry soil. M3 Average Value of plastic Limit = 27.25 Plasticity Index = LL – PL = 55.26 – 27.25 = 28.011 CONCLUSION: The experiment of the plastic limit was important to figure out the change moment of the plastic moisture content soil to the semisolid stage. Based on the tests an expected value of plasticity index is seen.
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Here you go--I hope that this gets you the grade you need. It's virtually impossible to avoid plagiarism in lab reports. I tried to mix things up, shorten and rephrase some things. I didn't want to lose the meaning of the instructions though. Anyway, take a look and tell me what you think. If we need to edit more we can. I'll be here for you if you need me.-Kevin

Liquid Limit and Plastic Limit Test

Group: C

LIQUID LIMIT TEST
INTRODUCTION:
Albert Atterberg, a Swedish chemist, developed a system of soil classification based
on what he termed the “limits of consistency”. Originally, Atterberg defined seven distinct
classes of fine-grained soils as his interest was primarily agricultural. Two of Atterberg’s
seven classifications are still used widely today in the field of geotechnical engineering—not
the agricultural field. The purpose of this exercise is to test one of those limits—the liquid
limit—in the laboratory.
Soil contains a heterogeneous mixture of minerals. The contents of one soil
sample may be affected differently than a separate soil sample after both are exposed to
water. The objective of this exercise is to induce soil to behave in one way as opposed to
another (soil can behave like a liquid or a plastic). The liquid limit of fine-grained soil refers
to its degree of saturation: more specifically, the moisture content that defines where the soil
changes from a plastic to a viscous fluid state.
This value is expressed as a percentage of the weight of oven-dried soil at its
liquid-plastic interface. The moisture content at this consistency interphase is somewhat
arbitrary defined as amount of water that will cause closure for a distance of 12.9 mm of a
standard groove in a remolded soil sample using 25 9.9mm drops in the liquid limit device.

APPARATUS:
1. Porcelain evaporating dishes approximately 115 mm in diameter.
2. Pulverizing apparatus - mortar and rubber-covered pestle.
3. U.S. No. 40 sieve.
4. Spatula, 75 mm long; 19 mm wide
5. Balance sensitive to 0.01 grams.
6. Water bottle containing distilled, demineralized or tap water.
7. Drying tares with covers which will prevent moisture loss.
8. Mechanical Liquid Limit Devic...


Anonymous
Awesome! Perfect study aid.

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