Assessment of the Reinforced Slope Stability Under Earthquake Loading

Failure of the soil slopes by dynamic excitation is one of the most vital geotechnical earthquake hazards which may lead to serious destruction to the bridge abutments, dams, embankment, and structures resting on the slope. Moreover, due to deficient space available for the construction of slopes in urban areas, high and steep slope is constructed by geotextile reinforcement slopes. In this study, numerical modelling is made to study the behaviour of soil slope reinforced by geotextile under earthquake loading using the finite element method available in, optumG2. The value of the factor of safety (FOS) for unreinforced soil slope is calculated using the strength reduction method (SRM) at slope angle (β = 60°) and the height of the slope is 10 m. In the unreinforced slope, a critical failure surface was obtained due to which slope is reinforced with geotextile under static and earthquake loading. Furthermore, a parametric analysis is carried out to evaluate the effect on different lengths of geotextile and different vertical spacing for the stability of reinforced slope with horizontal ground acceleration coefficient (0.1-0.4). From the outcomes of the present study, it is noted that a stable slope can be achieved with an optimized configuration of the reinforcement under seismic loading, also a steeper slope can be achieved using reinforcement compared to that of an unreinforced slope.

Indigenous Technique of Biochar Production and Effect of Biochar Application on the Geotechnical Properties of the Expansive Soils

Expansive soils have been a source of risk to human beings as they causes huge economic loss including damage to buildings, roads and other civil infrastructures because of their low compressive strength and excessive settlement characteristics. One of the available options is to replace such soils before starting any civil engineering construction but looking to huge costs involved in replacement; it is generally not practiced nowadays. Another viable alternative is to improve the engineering properties of such soils through stabilization. The conventional methods of stabilization make use of cement, lime, fly ash, rice husk ash, sawdust ash and other fibrous materials. Researchers are always finding alternative methods of soil stabilization making use of modern scientific techniques which are cost-effective as well as eco-friendly in nature. The present study focuses on producing biochar from agricultural crop residues and making use of it for stabilizing the expansive soils. India being an agricultural country produces a large volume of crop residues which creates an environmental problem in absence of proper management and disposal system. Indian farmers generally practice stubble burning in their fields which causes emission of greenhouse gases in the atmosphere and at the same time damage to the soil biota. A simple indigenous method of producing biochar has been developed wherein the crop residues are converted into biochar which is further applied to expansive soils as a stabilizing agent to improve the physical, chemical and engineering properties. In India, not much work has been carried out hitherto on biochar application to soils. The process of making biochar and the effects of utilizing biochar on the properties of expansive soil have been presented in this paper, which will prove useful for the Indian context where large quantities of agricultural wastes are produced that create environmental air pollution when burnt openly in fields.