Most contractors get a feel for these figures, based on their local experience. If you are dealing with a contractor who has not previously worked in the area, you should be wary. Method statement for vibro compaction works method statement hq. Standard test methods for laboratory compaction characteristics of soil using standard effort 12 400 ftlbfft 3600 knmm 1 this standard is issued under the. All three tests produce results with sufficient accuracy to determine the degree of compaction. This compaction method is used for compacting hollow blocks, cavity blocks, concrete blocks. Vibration impact kneading pressure soil compaction soil compaction is defined as the method of mechanically increasing the density of soil. Pdf laboratory concept produced by proctor 1933 has a few shortcoming in determining the value of maximum dry density mdd and. Lovell, department of civil engineering, purdue university, west lafayette, indiana laboratory compaction data and associated strength test results have been gen. Soil is compacted by removing air and water from its pore space.
Relative density is improved, potential for liquefaction from a seismic event is reduced, improvement depth up to 20. There are four types of compaction effort on soil or asphalt. Fundamentals of soil compaction intelligent compaction. D1196d1196m12 standard test method for nonrepetitive static plate load tests of soils and flexible pavement components, for use in evaluation and design of airport and highway pavements, v4. Sand replacement method is also known as sand cone method. The drier the soil, the more resistant it is to compaction. Potential products such as spun pipes are compacted by spinning process.
Compaction and mechanical properties of soils compacted. Compaction characteristic an overview sciencedirect topics. The reaction of the soil during the treatment varies with soil type and energy input. If drying is required, the same will be done by way of natural drying. D1557 12 standard test methods for laboratory compaction characteristics of soil using modi. The moisture content dry density relationship of the soil obtained from proctors test forms the basis for specification and field compaction control. Development of a simple method for determining mixing and. Sand compaction piles are one of the potential methods for improving ground stability, preventing liquefaction, reducing settlement and similar applications. Backfilling will be done using the approved fill material or select granular material as per drawings.
Soil compaction remediation needs an initial analysis of the soil to determine the possibility of compaction. An alternative method of creating a work platform is the. Cylindrical core cutters of mm long and 100mm diameter are used for testing the insitu compaction of cohesive and clay soils placed as fill. The determination of the field compaction is essential to acquiring the relative compaction of soil. Pdf comparison and effects of compaction methods on gradation. This provides the designer with assurance that the specified level of compaction will achieve the degree of improvement required. Soil compaction is defined as the method of mechanically increasing the density of soil. The department of transport specification for the compaction of fill materials around structures bridges etc. Harper formerly assistant research engineer william w. Dynamic compaction dc introduction dynamic compaction dc strengthens weak soils by controlled highenergy tamping dropping a static weight from a defined height.
Compaction of concrete method for compacting concrete. Dynamic soil compaction using various techniques can help to improve the bearing capacity of a soil and thus substantially reduce foundation costs. The number of tamping of strokes per layer varies with the type of concrete. Most field compaction tests are now made using nuclear density gages that employ a cesium element. This cohesion increases as the particle size decreases as in claytype soils. Methods of compaction of concreteconcrete technology. Accordingly, in this study, above vari ables were suitably controlled and their effects on the magnitude and variability of density and unconfined com pressive strength were established by statistical methods.
Mndots new base compaction specification based on the. Pdf static laboratory compaction method researchgate. An equivalent amount of energy input e is levied to all kinds of soil through dynamic compaction method, while the energy input by static compaction is different for each type of soil. The apparatus used in this field density test consists of a sand pouring cylinder, with pouring cone at its. Normally sand replacement method is adopted for this purpose. Seay supervising field engineer research report 902f research study number 266590 sponsored by. In a watersaturated state the voids between particles are partially filled with water, creating an apparent cohesion that binds them together. Use the following forms for projects awarded after july 1, 2016. The bottom is closed with a collapsible plate down to the required depth and then pipe is filled. Field density test of soil by sand replacement method.
Compaction increases the shear strength of the soil. Prior to handling test materials, performing equipment setups, andor conducting this method, testers are required to read safety and health in section f of this method. Engineers therefore appreciate the necessity for soil compaction and study soil classification and its effect on compaction before. Compaction of concrete methods and results of poor. Dry density of soil by core cutter method for soil compaction. Components of a method specification typically contain the type and size of compaction equipment.
There are many factors that should be considered to choose compaction methods such as reinforcement quantities and spacing, concrete paste consistency and formwork complexity. The compaction of concrete by hand is done by using a standard tamping bar. This method involves driving a hollow steel pipe into the ground. Compaction also helps to get the concrete to surround all the reinforcement steel and to fill all corners of the form, however small they may be. Vibro compaction is an established ground improvement method for stabilising granular soils such as loose sands, gravels and some hydraulic fills. There exists a certain amount of moisture that a soil can have where a maximum unit weight is. Once at depth the vibrolance performs a series of compaction intervals, starting from maximum depth of penetration upwards. Vibro compaction technique is applicable and effective for the improvement of loose natural fine sands as well as the compaction of fills.
While these methods have served the mndot well in the past, improved efficiency and quality in the inspection process are always desired. The number of passes needed to achieve the desired compaction depends on the lift thickness, contact pressure, and soil moisture content. The plastic concrete when at every high speed get well compacted by centrifugal force. Compaction % wsat % saturation % density passes yesno moisture passes yesno wc weight of cylinder in grams wcs weight of cylinder and soil in grams wmg wcs wc moist weight of soil in grams wm lbs wmg x 0. By using standard tamping bar, we can distribute the concrete in a uniform manner along the crosssection of the mould. Sand compaction pile technology and its performance in both sandy and clayey grounds to summarize, the features of the scp method are as follows. The technique is primarily used for seismic mitigation and insitu densification of loose sands up to 30m deep. Compaction of soil at maximum dry density is required in many engineering projects. Structural fill or backfill adjacent to structures shall be placed in 150 mm 6 in, compacted layers, or less if necessary to develop specified density.
Dynamic compaction dc quality control 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. Astm d 155707 test method for laboratory compaction. Degree of compaction the thickness of the lift is limited by the type and size of compaction equipment the contractor chooses to use. Soil compaction compaction is the application of mechanical energy to a soil to rearrange the particles and reduce the void ratio. The field density test of soil is conducted in the field to know whether the specified compaction is achieved or not. Methods of concrete compaction and types of vibrators. Foreword this publication, quality control of soil compaction using astm standards, was sponsored by committee d18 on soil and rock. The standard specifications indicate the maximum loose lift thickness and mechanical requirement for various types of compaction equipment such as pneumatictired. The present stud y i nvestigates this method of hydro compaction and discusses the limiting factors insight of results from field and laboratory tests carried out by flooding sand with water. During compaction, the vibrolance sustained vibrations agitate the particles and force the soil to rearrange to a denser state of compaction. The most widely used field tests for field compaction are. Vibro replacement method wet top feed vibro displacement method dry method vibro compaction. In this method, the stiff concrete is vibrated, pressed, and also given jolts. These methods are the specified density method, quality compaction method, and nuclear control strip method.
Astm d698 12e2 standard test methods for laboratory. Nuc gages can have significant errors if the extendable probe is located next to a rock 3 inches across. Compaction by hand the compaction of concrete by hand is done by using a standard tamping bar. Ground improvement with sand compaction piles advantages. Natural deposit as well as artificially reclaimed sand can be compacted to achieve desired bearing capacity and minimal settlement. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Pdf this paper, evaluates the effects of the conventional laboratory compaction methods on gradation, plasticity, shrinkage and strength of. Intelligent compaction rollers are used in compaction of hot mix asphalt for breakdown and intermediate compaction for method compaction process and for density required hma. This is manual 70 of the astm international manual series. Ground improvement by vibroflotation method vibroflotation. Pdf the sand compaction pile method pham ngoc thang. If concrete is well compacted, we achieve durable concrete, but over compaction also leads to the segregation of concrete. Compaction of concrete methods and results of poor concrete. Typically drop weights range from 620 ton dropped from heights up to 20m.
It is the responsibility of the user of this method to consult and use departmental safety and health practices. D155607 standard test method for density and unit weight of soil in place by the sandcone method, v4. Compaction should be applied uniformly to the entire concrete mass. Method statement for excavation compaction and backfilling. If required, the fill material will be ploughed to uniform water content before compacting. In construction, this is a significant part of the building process.
312 111 961 1077 180 611 1622 1284 1289 1556 408 158 333 993 1300 275 1376 19 175 833 655 801 533 1469 864 440 1434 1087 157 452 1073 422 995 1016 245 521