Effect of additives on geotechnical properties of soil in relation to erosion under simulated rainfall conditions
| dc.contributor.advisor | Akhilesh Kumar | |
| dc.contributor.author | Joshi, Pranjay | |
| dc.date.accessioned | 2018-12-21T11:21:46Z | |
| dc.date.available | 2018-12-21T11:21:46Z | |
| dc.date.issued | 2018-01 | |
| dc.description.abstract | The vulnerability of soil erosion towards erosion may be reduced by having a good vegetative cover over the soil surface, slope improvement and improving soil properties so that it is not easily detached and transported. However, establishment of proper vegetative cover is time taking process as it takes time for a seed to germinate and attain maturity. As an alternative approach, if soil resistance is increased by increasing the shear strength of soil against erosive forces offered by eroding agents, the soil system will become capable of withstanding the detachment of its particles on the application of shear stress. Under this practice, an additive is mixed to the soil which increases the shear strength of soil. The additives range from biodegradable to non-biodegradable or partially biodegradable inert materials. Recently, the use of guargum polymer in agriculture has become quite popular. Some recent applications of Guar gum are in the field of drag reduction in pipes, evaporation control, soil stabilization and erosion control. Accordingly, in this study, additives namely jute fibre and guargum and their combinations were mixed with soil in different proportions to study various geo-technical properties such as dry density, optimum water content, California bearing ratio (CBR) and tri-axial shear parameters. Index properties like specific gravity, grain size distribution and consistency limits and geotechnical properties such as dry density and optimum moisture content of treated and untreated soils were determined. California bearing ratio (CBR) value was used to evaluate mechanical strength of soil. There were nine treatments for which CBR values were determined. for two stages i.e., for the1st day of treatment and on the 4th day after the treatment. The tri-axial test was performed to obtain values of shear parameters at three confining pressures of 1kg/cm2, 1.5kg/cm2 and 2 kg/cm2 for a particular percentage of additives. Deviator stress was subjected from the top and the loading rate of 1.25 mm per minute was kept throughout the experiment. The unconsolidated undrained (UU) conditions were maintained throughout the experiment. For untreated soil, the value of cohesion was found to be 0.49 kg/cm2and angle of internal friction was found to be 28.66 degree on the1st day. The cohesion and angle of internal friction increased to 1.593kg/cm2and 55.35 degrees respectively on 7thday. Similarly, these values were obtained for all treatments applied to soil to determine shear parameters. To produce rainfall a small size portable rainfall simulation system was developed in the laboratory which was1m x1m in size and operated from a height of 5 meter. The simulator was calibrated for its rainfall generation capabilities which commensurate with natural rainfall conditions. The simulation system was calibrated for producing rainfall intensities of 12.8 cm/h t and 17.5 cm/h for water pressures of 0.4 kg/cm2 and 0.5 kg/cm2 which occurred almost uniformly over the entire test plot. The soil was treated with guargum having 0.3%, 0.5%, and 0.7% concentration by weight and with jute fiber having 0.3%, 0.5%, and 0.7% by weight and also with guargum and jute fiber combinations as 0.3%guargum and 0.3% Jute; 0.5% guargum and 0.5% jute; and 0.7% guargum and 0.7% jute mixture by weight. The recorded observations clearly revealed that as the value of shear strength of soil increased as the result of the applied treatments, the soil loss rate/ sediment outflow rate decreased for every combination of land slope and rainfall intensity. It was also found that for a particular value of cohesion and angle of internal friction, the runoff rate increased with rainfall intensity for every land slope while the sediment concentration and sediment outflow rate increased with rainfall intensity as well as land slope. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810086223 | |
| dc.keywords | additives, geology, soil properties, soil erosion, simulation, rain | en_US |
| dc.language.iso | en | en_US |
| dc.pages | 122 | en_US |
| dc.publisher | G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand) | en_US |
| dc.research.problem | Soil Erosion | en_US |
| dc.sub | Soil and Water Engineering | en_US |
| dc.subject | null | en_US |
| dc.theme | Soil and Water Conservation | en_US |
| dc.these.type | M.Tech | en_US |
| dc.title | Effect of additives on geotechnical properties of soil in relation to erosion under simulated rainfall conditions | en_US |
| dc.type | Thesis | en_US |