Soil Compaction - 9893 Words

FM 5-410 CHAPTER 8 Soil Compaction Soil compaction is one of the most critical components in the construction of roads, airfields, embankments, and foundations. The durability and stability of a structure are related to the achievement of proper soil compaction. Structural failure of roads and airfields and the damage caused by foundation settlement can often be traced back to the failure to achieve proper soil compaction. Compaction is the process of mechanically densifying a soil. Densification is accomplished by pressing the soil particles together into a close state of contact with air being expelled from the soil mass in the process. Compaction, as used here, implies dynamic compaction or densification by the application†¦show more content†¦Volume change is generally not a great concern in relation to compaction except for clay soils where compaction does have a marked influence. For these soils, the greater the density, the greater the potential volume change due to swelling, unless the soil is restrai ned. An expansive clay soil should be compacted at a moisture content at which swelling will not exceed 3 percent. Although the conditions corresponding to a minimum swell and minimum shrinkage may not be exactly the same, soils in which volume change is a factor generally may be compacted so that these effects are minimized. The effect of swelling on bearing capacity is important and is evaluated by the standard method used by the US Army Corps of Engineers in preparing samples for the CBR test. Section II. Design Considerations MOISTURE-DENSITY RELATIONSHIPS Nearly all soils exhibit a similar relationship between moisture content and dry density when subjected to a given compactive effort (see Figure 8-1). For each soil, a maximum dry density develops at an OMC for the compactive effort used. The OMC at which maximum density is obtained is the moisture content at which the soil becomes sufficiently workable under a given compactive effort to cause the soil particles to become so closely packed that most of the air is expelled. For most soils (except cohesionless sands), when the moisture content is less than optimum, the soil is more difficult to compact. Beyond optimum, most soilsShow MoreRelatedAnalysis of Test Results2141 Words   |  9 Pagesof Test Results Problems with guessing the compaction curve from the Family of Curves Out in the field, some testers interpolate a compaction curve to represent the material using the Alberta Family of Curves. One of the goals of this applied research, was to test the accuracy of this method. It was concluded that the only true way to verify the legimitacy of this curve is by doing index testing such as atterberg limits and grain size analysis on the soil. The City of Edmonton does require the testingRead MoreInvestigating The Relationship Between Molding Water Content And Dry Unit Weight Of Soils Essay1051 Words   |  5 PagesThe purpose of this experiment was to determine the relationship between molding water content and dry unit weight of soils. This was done by performing the laboratory compaction test using standard effort on the same soil at different moisture contents. When the density of the soil is plotted over moisture content, a concave down curve is generated. This is because adding moisture increases density until it reaches its optimal moisture, then adding further moisture decreases density. UnderstandingRead MoreBenefits Of A Sustainable Soil Management Essay1427 Words   |  6 Pages Sustainable soil management is about the fruitful management of agricultural resources to fulfill human needs while preserving or enhancing environmental excellence and conserving natural resources for future groups. Enhancement in agricultural sustainability entails, together with effective water and crop management, the optimal utilization and soil fertility management and soil physical properties, which depend on biological processes and biodiversity in the soil. These finding a proper choicesRead MoreEvaluation Of A Project Feasibility Study For Geotechnical Projects1629 Words   |  7 PagesAbandoned sites due to undesirable soil bearing capacities dramatically increased, and the outcome of this was the scarcity of land and increased demand for natural resources. Affected areas include those which were susceptible to liquefaction and those covered with soft clay and organic soils. Other areas were those in a landslide and contaminated land. However, in most geotechnical project s, it is not possible to obtain a construction site that will meet the design requirements without ground modificationRead MoreFactors that Affect Plant Growth1095 Words   |  4 Pagesmany different variables. Temperature, amount of sunlight and pH of soil are all factors that can affect the growth and development of a plant. Environmental factors can either allow plants to thrive, or leave them unable to grow and die. One important factor is the quality of the soil the plant is growing in. Urban development of land can have a serious impact on the soil, shaping how healthy a plant can be, while, understandably, soil in untouched areas of land would be of far better quality and betterRead MoreSoil Is A Vital Part Of The Natural Environment1352 Words   |  6 PagesSoil is a vital part of the natural environment. Without soil the land on Earth would be wastelands of barren rock. Soil is the thin skin of our earth where we plant and grow vital grain crops such as wheat, corn and ri ce that feed more than seven billion of us. The future rests on the soil beneath our feet. History is littered with the remains of civilizations that ignored, exploited and degraded the soil beneath their feet. One-third of the world’s soil has already been damaged by wind and waterRead MoreGround Improvement Techniques3816 Words   |  16 Pagesrequirements, by altering the natural state of the soil, instead of having to alter the design in response to the grounds natural limitations. The results usually include saving in construction cost and reduction of implementation time. There are number of techniques available for improving the mechanical and engineering properties of the soil. However, each technique has some limitations and suit abilities to get maximum improvement in the soil conditions with minimum effort. Some of theRead MoreSuitability And Future Soil Management2269 Words   |  10 Pagesthis report is to determine the suitability of the clients soil, indicated with in the marked area in fig 1. (google,2016), where they propose to transplant two semi mature trees, which would otherwise be felled due to a major rail development near by. This survey aims to provide the client with information on existing soil profiles, obtain site specific soil samples, which will be analysed recommendations for suitability and future soil management will then be made in a conclusion based on siteRead More The Effects of Grazing and Trampling Behaviors of Large-Sized Livestock on the Formation and Weathering Patterns of Soils2368 Words   |à ‚  10 PagesThe Effects of Grazing and Trampling Behaviors of Large-Sized Livestock on the Formation and Weathering Patterns of Soils Introduction Walter Coppinger, a Professor of Geosciences at Trinity College in San Antonio and long-time observer of Montana geology, was the first person to describe to me the many problems of the western rangelands that have developed out of the over-grazing of cattle. From a hilltop among the upland slopes of Whitehall, Montana, he pointed out a few patches of bareRead MoreConstruction Of Roads For Black Cotton Soil1207 Words   |  5 PagesINTRODUCTION : Construction of roads in black cotton soil areas has been problematic due to their low bearing capacity and the detrimental effects of volume instability arising from swelling and shrinkage characteristics of such soils during wet and dry seasons. Such problems assume greater acuteness where the water table is high and clayey subsoil stratum is thick. A Perfect example of a case history study can be considered from â€Å"Gudivada-Bantumilli† State Highway, which passes through a plain