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The Effect Of Sodium Sulphate Contamination On Engineering Properties Of Lateritic Soil
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2.2 ENGINEERING PROPERTIES OF LATERITIC SOIL
Geology and geotechnical nature, field situation and performance of lateritic soil as well as their reactions to various and different stabilizing agents which may be explained based on the following profound parameters (Gidigasu, 1976).
- Genetics and pedological factors (parent rock) terrain, climate, vegetation and period of time in which the process has performed.
- Degree of wethering ( decomposition, sasquioxides enrichment and clay size content) degree of leaching.
- Position in the topographic site and
- Depth of soil in the profile.
2.2.1 PARTICLE- SIZE DISTRIBUTION OF LATERITIC SOIL
Particle size distribution may provide the following information:
- A basis for identification and classification of soils.
- The compatibility characteristics
- Permeability
- Swellability and
- A rough idea of deformation characteristics of the soli mass.
Texturally lateritic soils are very viable and may contain all fractional sizes; boulders, cobbles, gravel, sand, silt and clay and well as concreting rocks.
Protesting preparation of lateritic soils are sieve analysis may have the following effects on the size distribution (Olawole, 2013).
- Remoulding and removal of free iron oxides increases the content of fines between 35% to 65% ( this will be a function of the dispersing agent).
- Degree of drying and time mixing of the sample prior to testing, influence the degree of dispersion of some lateritic soils.
- Cementing effects of sesquioxides, which bind the clay and silt fractions into coarser fraction.
2.2.2 PLASTICITY CHARACTERISTICS OF LATERITIC SOIL
From the knowledge of Atterberg limits whch is a basis of determining the liquid limit, plastic limit, plastic index,liquidity index and flow index of a given soil.
Atterberg limits depend on
- The amount of clay
- Nature of soil mineral and organic matter content
- Chemical composition of the soil environment
- Nature of exchangeable cations
- Organic matter and high organic matter
Protest preparation, degree of moulding and time mixing, dry and re-welting and irreversible changes may affect plasticity test in drying. Drying drives off absorbed water, which is not completely regained, on re-welting (this is the case in both oven and air drying)(Olawole, 2013).
Profound studies and analysis made on the relationship that exists between the natural moisture content and the liquid limits and plastic limit in normal lateritic soils. Also the lateritic soils derived from high rainfall region may have high moisture content and liquid limit (Sherwood, 1992 and Mumeen,2009).
2.2.3 COMPACTION CHARACTERISTICS OF LATERITIC SOIL
The compaction characteristics of lateritic soil are determined by their grading characteristics and plasticity of fines. These in turn can be traced to genetics and pedological factors.
The significant characteristics of lateritic soil are influenced by the strength of concretionary coarse particles on compaction. Most lateritic soils contain a mixture of quartz and concretionary coarse particles which may vary from very Hard to very soft.
The strength of these particles has major implication in terms of field and laboratory compaction result and their subsequent performance in road pavement. The higher the iron oxides content, then the higher the degree of dehydration in the lateritic soil, the harder the concretionary particles become.
Placement variable(moisture content, amount of compaction and type of compaction efforts) also influences the compaction characteristics, varying each of these placement variables has an effect on permeability, compressibility, swellability, strength and stress-strain characteristics (Olawole, 2013).
From the basic principle, soil that undergoes compaction process on the dry side of optimum moisture contents swells more than soils compacted on the dry side having a lower moisture rate and a lower degree of saturation. Also, the soil compacted on the wet side of the optimum moisture content will shrink more than a soil compacted on the dry side (Mumeen, 2009).
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ABSRACT - [ Total Page(s): 1 ]ABSTRACT COMING SOON ... Continue reading---
APPENDIX A - [ Total Page(s): 3 ] ... Continue reading---
CHAPTER ONE - [ Total Page(s): 2 ]CHAPTER ONE1.0 INTRODUCTIONSoil is the cheapest and the most widely used material in civil engineering project as foundation material either in its natural or improved form. It is highly heterogeneous and an isotopic in nature and existing with different engineering properties which can be influenced to some extend by the presence of sodium salts under the influences of water (Olawale, 2013). ... Continue reading---
CHAPTER THREE - [ Total Page(s): 3 ]PROCEDURES• Liquid limit: A sample weighing 200g from the material passing the 300um BS test sieve was taken.• The sample was placed on flat glass plate and mix thoroughly with distilled water using the palette knife unit the mass becomes a thick homogonous paste.• The paste was allowed to stand in air tight container for about 24hours to allow the water permeate throughout the soil mass.• Curing was applied to where applicable and remix for about ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 16 ]CHAPTER FOURRESULT ANALYSIS AND DISCUSSION4.1 PARTICLE SIZE DISTRIBUTIONThe result of the particle size distribution “sieve analysis†of the sample is analyzed and presented in the table and figure below. ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 1 ]CHAPTER FIVE5.1 CONCLUSION From the investigations carried out on this work, the following conclusions are made: The laterite sample is classified as Sand Gravel soil according to AASHTO classification system and it is a good sub grade and sub-base material for Civil Engineering construction.The liquid test for unstabilized laterite is 60.31% and for the stabilized of 20% is 50.16,30 % is 46.9% and for 40% is 45.05 and plastic limits test for unstabilized laterite is 36.62% and ... Continue reading---
REFRENCES - [ Total Page(s): 1 ]REFERENCESAbabio, O.Y. (1996), New School Chemistry for Senior Secondary School (2nd edition), Longman publisher, Erands, LondonAbraham, J. (1992), “Introduction to Soil Mechanics†(3rd edition), Macmillan INC, New York.Agbede, O. and osunmolale O. (1997), “All AboutSulphate Salt†Retrieved 2009-10-31â€. From www.ifgworld.org. Agbede, O. and Osunolale O. (2003), “Effect of Ph Contamination on Engineering Properties of Lateritic Soilâ€. Final Year Project i ... Continue reading---
