Effects of Periwinkle Shell Ash on Lime-Stabilized Lateritic Soil

This study assesses the effects of periwinkle shell ash (PSA) on lime-stabilized lateritic soil. Preliminary tests were carried out on the natural soil sample for the purposes of identification and classification. The soil sample was classified as A-7-5. Thereafter, the soil sample was mixed with lime at percentages of 2, 4, 6, 8 and 10. These were later subjected to atterberg limit tests to get the optimum amount of lime, which was 10% because the least value of plasticity index was recorded at this state. PSA was added to the lime-treated soil sample at varying proportions of 2, 4, 6, 8 and 10%. The mixes were subjected to compaction, California bearing ratio (CBR), atterberg limits and unconfined compressive strength (UCS) tests, in so doing, the values of the CBR and UCS increased considerably. It can be concluded that the PSA performs satisfactorily as a cheap complement for lime in soil stabilization.Keywords: atterberg limits, lateritic soil, lime stabilization, periwinkle shell ash, soil stabilizatio

Geotechnical Properties of Lateritic Soil Stabilized with Ground-Nut Husk Ash

This study assesses the geotechnical properties of lateritic soil stabilized with Ground-nut Husk Ash. Preliminary tests were carried out on the natural soil sample for identification and classification purposes, while consistency limits tests were thereafter carried out as well. Engineering property tests such as California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS) and compaction tests were performed on both the natural soil sample and the stabilized lateritic soil, which was stabilized by adding Ground-nut Husk Ash, GHA, in percentages of 2, 4, 6, 8 and 10 by weight of the soil.  The results showed that the addition of GHA enhanced the strength of the soil sample. The Maximum Dry Density (MDD) reduced from 1960 kg/m3 to 1760 kg/m3 at 10% GHA by weight of soil. The Optimum Moisture Content (OMC) increased from 12.70% to 14.95%, also at 10% GHA by weight of soil. The unsoaked CBR values increased from 24.42% to 72.88% finally, the UCS values increased from 510.25 kN/m2 to 1186.46 kN/m2, for both CBR and UCS, the values were at 10% GHA by weight of soil. It was therefore concluded that GHA performs satisfactorily as a cheap stabilizing agent for stabilizing lateritic soil especially for subgrade and sub base purposes in road construction

Evaluation of the effects of waste glass in asphalt concrete using the Marshall test

The study investigates the use of waste glass as filler in asphalt concrete. Waste glass constitutes a significant proportion of the waste generated in both developed and developing countries. Successful utilization of the waste glass in asphalt will reduce the problem faced by environmental agencies at ensuring safe disposal of the non-biodegradable waste and may improve the asphalt properties. In the study, a waste glass in form of a filler was introduced into the asphalt mix at 8%, 10%, 12%, 14%, 16%, 18% and 20% of the total mix. The asphalt concrete samples with and without waste glass as filler were subjected to the Marshall test to determine the stability, flow, air voids, void in mix aggregate and void filled with bitumen. The Marshall test results show that stability increases when increasing glass filler up to 18%, although the values were lower than of the asphalt concrete without waste glass. This implies improved resistance to fatigue for higher waste glass content. Also, the flow increases with increasing glass filler, which implies the resistance to permanent deformation which did not improve. Generally, the introduction of waste glass in the asphalt concrete is environmentally friendly, and it will aid the sustainable management of waste glass

Geotechnical Properties of Lateritic Soil Stabilized with Banana Leaves Ash

This paper investigated the geotechnical properties of lateritic soil with banana leaves ash. The natural soil sample was gotten from the Federal University of Technology, Akure (FUTA), Nigeria, and were subjected to preliminary soil tests such as natural moisture content, specific gravity and atterberg limit at its natural state. Engineering tests such as compaction, california bearing ratio and unconfined compressive strength tests  were also carried out on the lateritic soil at their natural states and at when the banana leaves ashes were added to the soil at varying proportions of 2, 4, 6, 8 and 10% by weight of soil. The result of the strength tests showed that the banana leaves ash enhanced the strength of the lateritic soil. The unsoaked CBR value of the soil at its natural state was 10.42 % and it got to optimum value of  28.10% by addition of 4% banana leaves ash by weight of soil. The unconfined compressive strength improved from 209.18 kN/m2  at natural state to 233.77 kN/m 2  at 4% banana leaves ashes. It was therefore concluded that the banana leaves ash satisfactorily act as cheap stabilizing agents for subgrade purposes

Geotechnical and microstructural properties of cement-treated laterites stabilized with rice husk ash and bamboo leaf ash

This study investigated the geotechnical and microstructural properties of cement-treated laterites stabilized with rice husk ash and bamboo leaf ash. In going about the tests, the soil sample was subjected to compaction, California Bearing Ratio (CBR) and preliminary tests; such as specific gravity, particle size distribution and Atterbergs limits to determine its index properties. Thereafter, the soil sample was mixed with cement at varying proportions of 0–12% at 2% intervals and also, separately mixed with bamboo leaf ash (BLA) and rice husk ash (RHA) in proportions of 0–16% at 2% intervals. The mixes at each stage were subjected to compaction, Atterberg limits and CBR tests. The highest values were 66.7% and 54.8% for unsoaked and soaked CBR at 6% cement+8% BLA and 78.5% and 63.8% for unsoaked and soaked CBR at 8% cement+8% RHA. Samples at these optimal CBR values were subjected into Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) tests. Results showed that new compounds were formed and there were changes in the microstructural arrangements. It can therefore be concluded that pozzolanic and cement hydration reactions actually took place in the course of stabilization

The effects of potassium permanganate on the geotechnical properties of soils

In Nigeria, potassium permanganate (KMnO4) is used as a chemical oxidant in the removal of hydrocarbons from polluted soils and groundwater, but there is no information on the effects of KMnO4 on the geotechnical properties of the soil. In this study, KMnO4 was added separately to lateritic soil and kaolin at concentrations of 0 %, 2 %, 5% and 10 % by weight of dry soil. Each of the mixes was then subjected to grain size analysis, Atterberg limits, specific gravity, compaction, and California bearing ratio (CBR) tests. The results showed that an increase in KMnO4 from 0 % to 10 % generally decreased the values of maximum dry density (MDD), optimum moisture content (OMC) and both unsoaked and soaked CBR for both soils. In conclusion, the study shows that although KMnO4 is excellent for the remediation of contaminated sites, it reduces the geotechnical properties of soil and therefore should not be used alone (without the use of other additives) for soil stabilisation

Effects of Coarse Aggregate Size on the Compressive Strength of Concrete

This study investigates the effect of aggregate size on the compressive strength of concrete. Two nominal mixes, that is, 1:2:4 and 1:3:6 were used in the study. Concrete cubes were produced with 6, 10, 12.5, 20 and 25 mm aggregates for the two nominal mixes and they were subjected to compressive strength test after curing for 7, 21, 28 and 56 days. It was found in the study that the strength development follows the same trend for both nominal mixes. Also, the results show that the compressive strength increases with increasing aggregate size up to 12.5 mm, while the concrete produced using 20 mm had greater compressive strength than those produced using 25 mm aggregate. This established the importance of ensuring that the right aggregate size is used in the production of concrete. Therefore, it is recommended that careful attention must be paid to the sizes of aggregates used in the production of concrete for structural purposes

The effects of potassium permanganate on the geotechnical properties of soils

In Nigeria, potassium permanganate (KMnO4) is used as a chemical oxidant in the removal of hydrocarbons from polluted soils and groundwater, but there is no information on the effects of KMnO4 on the geotechnical properties of the soil. In this study, KMnO4 was added separately to lateritic soil and kaolin at concentrations of 0 %, 2 %, 5% and 10 % by weight of dry soil. Each of the mixes was then subjected to grain size analysis, Atterberg limits, specific gravity, compaction, and California bearing ratio (CBR) tests. The results showed that an increase in KMnO4 from 0 % to 10 % generally decreased the values of maximum dry density (MDD), optimum moisture content (OMC) and both unsoaked and soaked CBR for both soils. In conclusion, the study shows that although KMnO4 is excellent for the remediation of contaminated sites, it reduces the geotechnical properties of soil and therefore should not be used alone (without the use of other additives) for soil stabilisation

Effects of corn cob ash on lime stabilized lateritic soil

This study assesses the effects of Corn Cob Ash (CCA) on lime-stabilized lateritic soil. Preliminary tests were carried out on the natural soil sample for purpose of identification and classification. Lime being the main stabilizing material was thoroughly mixed with the soil sample to determine the optimum lime requirement of the sample as a basis for evaluating the effects of the CCA. The optimum lime requirement was 10%. The CCA was thereafter added to the lime stabilized soil in varying proportions of 2, 4, 6, 8 and 10%. Unsoaked CBR increased from 83% at 0% CCA to highest value of 94% at 4% CCA. Unconfined Compressive Strength (UCS) values increased from 1123kN/m2 at 0% CCA to highest value of 1180kN/m2 at 4% CCA. It was therefore concluded that CCA can serve as a good complement for lime stabilization in lateritic soil

GEOTECHNICAL CHARACTERISTICS OF LATERITIC SOIL STABILIZED WITH SAWDUST ASH-LIME MIXTURES

This study assesses the geotechnical characteristics of lateritic soil and sawdust ash lime (SDAL) mixtures. Preliminary tests were carried out on the natural soil sample for identification and classification purposes. The sawdust was mixed with lime for stabilization in the ratio 2:1. This mixture was thereafter added to the lateritic soil in varying proportions of 2, 4, 6, 8 and 10% by weight of soil. Addition of SDAL increased values of Optimum Moisture Content (OMC) from 17.0% at 0% SDAL to 26.5% at 10% SDAL by weight of soil, also, values of Maximum Dry Density (MDD) decreased from 2040 kg/m3 at 0% SDAL to 1415 kg/m3 at 10% SDAL. Values of Unconfined Compressive Strength (UCS) increased from 38.58 kN/m2 at 0% SDAL to highest value of 129.63 kN/m2 at 6% SDAL. The values of liquid limits and plasticity index of the soil were effectively reduced with the addition of the SDAL, from 54.0% at 0% SDAL to 49.0% at 10% SDAL and from 13.7% at 0% SDAL to 12.5% at 10% SDAL respectively. It was therefore concluded that the sawdust ash lime (SDAL) mixture can serve as a cheap soil stabilizing agent for poor lateritic soil