The most direct effect of soil compaction is an increase in the bulk density of soil. For the same type of soil, the modified proctor yields a higher maximum dry density and lower optimum moisture content. The proctor compaction test is a test that compacts the soil material at various moisture contents. Deep soil compaction is excessive soil compaction below the normal annual tillage depth, usually 1520 cm. Compaction is the application of mechanical energy to a soil to rearrange the particles and reduce the void ratio. In other words, the density is a comparison of the weight of one cubic foot of material in the field. Oct 28, 2016 standard procter test diameter of mold volume of mold weight of hammer height of hammer drop number of hammer blows per layer of soil number of layers of compaction energy of compaction method a method b method c 101. This provides the designer with assurance that the specified level of compaction will achieve the degree of improvement required. Soil compaction is the process of increasing the density of soil by packing the soil particles closer together causing a reduction in the volume of air. Soil compaction concerns have been growing in minnesota as both annual precipitation and farm equipment size have dramatically increased. The water contentdensity relationship indicating the increased density resulting from the addition of water and applied compaction effort.
Standard procter test diameter of mold volume of mold weight of hammer height of hammer drop number of hammer blows per layer of soil number of layers of compaction energy of compaction method a method b method c 101. Test frequency nd t 180 or nd t 99, moisturedensity relations of soils multipoint 1 compaction curve for each change in soil. Proctor showing that for a given compaction effort, the density of soil depends on the type of soil and moisture content. Jul 19, 2014 a typical field testing procedure to determine the load bearing capacity of t. Compaction definitions soil compaction decrease in soil volume and porosity, or increase in soil bulk density, due to mechanical stress on soil, for example, from traffic of agricultural machinery. Soil compaction is the process in which stress is applied to a soil which causes densification as the voids are filled with solids. Compaction of soil is the optimal moisture content at which a given soil type becomes most dense and achieve its.
Soil compaction testing otherwise known as density tests are performed in order to determine the soil compaction level. Soil compactors are used to perform test methods which cover laboratory compaction methods used to determine the relationship between molding water content and dry unit weight of soils. Compaction of soil purpose and effects of soil compaction. For instance, a compaction test similar to the bs light test but using, say, 50 blows per layer. Compaction of soil process, necessity and theory of. Soils field testing dig a hole with the auger, trowel, or other tools test hole must be approx. What to do about compacted soil college of agriculture. A typical field testing procedure to determine the load bearing capacity of t. Compaction increases the shear strength of the soil. Im 216 guidelines for determining the acceptability of test results. It is normal procedure to test treated ground during the progress of the compaction works for control purposes to assess the effectiveness of the treatment. Compaction of soil test methods and effect on properties. Im 309 determining standard proctor moisture density relationship of soils. Generally, a geotechnical engineer will provide recommended specifications to.
Wet soils are particularly susceptible to compaction. See what fertilizers are recommended in the text below recommendations. In this edition of the roadready newsletter, we will focus on measuring the density of a pavement and therefore how well it was compacted, as well as examining the challenges around to obtaining proper compaction. May 01, 2017 types of soil compaction test in laboratory standard proctor test modified proctor test gyratory compaction test 11. Soil water acts as a lubricant increasing compaction when a load is imposed on the soil. Determination of water contentdry density relation using light compaction. Nd d 2167, density and unit weight of soil in place by the rubber balloon method, or nd t 191, density of soil inplace by the sand cone method 1 test per 1,500 feet of compacted roadway per 12 lift. Compaction of soil is the optimal moisture content at which a given soil type becomes most dense and achieve its maximum dry density by removal of air voids. Compaction of soil process, necessity and theory of compaction. Compaction and measuring pavement density pavement. Soil type gradation, presence of clay minerals, etc.
Manual 70, quality control of soil compaction using astm standards, combines established soil mechanics engineering fundamentals and the discussions on using the latest astm standards related to those fundamentals. These generally involve compacting soil into a mould at various moisture contents. According to proctor, the compaction of a soil mass is dependent on the following four major factors. Our team consists of qualified professionals from a range of backgrounds with varying experience and skill sets, this allows us to provide our clients with expert guidance that you. Surface compaction compaction that occurs in the surface plow layer. Plants do not grow as well as they should, developing inadequate root systems. There are two proctor tests that defined by the american association of highway officials and american standard testing material. Soils field testing north dakota department of transportation. The location of the test should be determined accurately.
Soil compaction testing, or density tests, are vital to the construction and engineering sectors and are performed in order to determine the soil compaction level. Heavy equipment and tillage implements amplify damage to the soil s structure, decreasing pore space and limiting soil and water volume even further. Heavy equipment and tillage implements amplify damage to the soils structure, decreasing pore space and limiting soil and water volume even further. Methods of testing compaction of soil standard proctors test for compaction of soil. May 14, 20 objective for determination of the relation between the water content and the dry density of soils using light compaction. The moisture content dry density relationship of the soil obtained from proctors test forms the basis for specification and field compaction control. Standard proctor test or proctor compaction test was the original test devised by an american engineer ralph r. Manual of soil laboratory testing 314 every different degree of compaction on a particular soil results in a different compaction curve, each with unique values of optimum moisture content and maximum dry density. Standard test methods for laboratory compaction characteristics of soil using standard effort 12 400 ftlbfft 3600 knmm 1 this standard is issued under the. If near saturation, however, the load is likely to exceed the soil strength and bearing capacity.
The standard proctor test astm d698, aashto t99, and the modified. The best way to test is to probe the soil with a compaction tester to a depth of 36 to 48. Compaction tests results vary with the input compactive effort, usually measured in footpounds per cubic foot of soil. The specification can include information on soil preparation requirements, minimum density to be achieved, moisture range, degree of saturation limits, layer thickness ranges, roller types and characteristics, and other specific features, such as shoulders and edges. If performed improperly, settlement of the soil could occur and result in unnecessary maintenance costs or structural failure. Pdf field application of soil compaction isbel yap. Soil compaction occurs below the surface, so its hard to spot. Diagnosing soil compaction using a penetrometer soil. Compaction of soil is an important process, as it helps it of achieve certain physical properties necessary for its proper behaviour under loading. Soil is a silty clay, ll 37, pi 14, standard proctor compaction after johnson and sallberg, 1960. Compaction tests results vary with the input compactive effort, usually measured in foot pounds per cubic foot of soil. Sep 15, 2010 in asphalt pavement construction, its compaction, compaction, compaction. Soil compaction can easily reduce crop yields by 10 percent, and can lead to water and soil quality degradation due to increased runoff and soil structure destruction.
Test strips are useful to determine which type of compactor and how many passes will be necessary to achieve the desired compaction in this example, p is pneumatic tire roller. Laboratory soil compaction test linkedin slideshare. A curve is drawn between the water content and the dry density to obtain the maximum dry density and the optimum water content. Proctor soil compaction test procedures, tools and results. Low density pavements can impact project payment incentives and in the longer term could cause accelerated failures where poorly compacted pavements. In the proctor test, the soil is compacted in a mold that has a volume of 944 cm3. He sometimes faltered in pronouncing the names of those receiv. Terry had risen to the leadership of committee d18 through his 20 years of exemplary hard work and quality performance. Both the original and modified here the modified proctor compaction test 1946. Dynamic cbr test to assess the soil compaction article pdf available in journal of testing and evaluation 435.
This plays a vital part in construction for soils are mainly used as supports for a lot of infrastructures. A new publication available from astm international provides the latest information on the proper application of astm standards for soil compaction for various earthworks. Modified proctor aashto t180astm d1557 testing procedures more closely approximate the compaction effort of modern equipment. Standard proctor test procedure apparatus calculation. Quality control of soil compaction using astm standards. If a heavier degree of compaction corresponding to the bs heavy compaction test section 6. What to do about compacted soil gretchen voyle and hal hudson, michigan state university extension gardeners are sometimes unaware of the problems soil compaction can cause in lawns, flower beds and gardens. Measures density of soil for comparing the degree of compaction vs specs.
The principal reason for compacting soil is to reduce subsequent settlement under working loads. The final soil survey is done after the line for a project has been approved by the location and design division. This compaction is a comparison of the laboratory compaction proctor to the field density and recorded as a percentage. This paper presents a brief historical account of soil compaction development. Soil compaction compaction is the application of mechanical energy to a soil to rearrange the particles and reduce the void ratio. The number of drops required to drive the cone a distance of 3. Effects of soil compaction on soil and crop health. Poor compaction decreases pavement quality failures such as rutting, raveling and moisture damage are commonly attributed to poor compaction, and as a result, this is one of the main metrics measured when assessing quality. If there is a major problem with the soil ph, it is recommended that the clients do a follow up soil test to check the ph in one year after limesulfur applications. The fertilizer rates listed are based on the soil test results in the bar graph to make it easy. Types of soil compaction test in laboratory standard proctor test modified proctor test gyratory compaction test 11. Subgrade soils prior to the application of topsoil see permanent seeding and stabilization notes for topsoil requirements shall be free of excessive compaction to a depth of 6.
Astm d7380 15 standard test method for soil compaction. Each of these tests can be performed in three different methods as outlined in the attached table 1. Standard test methods for laboratory compaction characteristics of soil using modi. Compaction of soils is a major construction activity in civil engineering, and particularly in the transport industry. Specification of compaction for field soil is a major undertaking in construction projects. Standard proctor test, the soil is compacted by a 5. As water is added to a soil at low moisture content it becomes easier for the particles to move past one another during the application of the compacting. Soil compaction is a serious concern for farmers in pennsylvania. Soil placed as engineering fill is compacted to a dense state to obtain satisfactory engineering properties such as, shear strength, compressibility, or. Some of the yield loss was recovered by k fertilization, but the best yields were found when the soil was. Compaction of soil is the application of mechanical energy to a soil to rearrange the particles and reduce the void ratio and increase soil density. Compaction and measuring pavement density pavement interactive. What types of soil tests required for building construction.
This publication, quality control of soil compaction using astm standards, is dedicated to the memory of former committee d18 chairman, terry hawk. Determination of water content dry density relation using heavy compaction. We know that the conditions of site and that of the laboratory are different altogether. Test data is used for support of building foundations, roads and other earth retaining structures. The line of optimum moisture contents is usually around 85% saturation and the optimum moisture content decreases with increasing compactive effort. Soil test k had been adjusted to either the optimum or high category and row k fertilizer was applied to half of the plots. The testing rod should move down through the soil with steady, even pressure, hard, compacted soils resist penetration with the rod.
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