Recursos de colección

ETD at Indian Institute of Science (3.494 recursos)

Repository of Theses and Dissertations of Indian Institute of Science, Bangalore, India. The repository has been developed to capture, disseminate and preserve research theses of Indian Institute of Science.

Civil Engineering (civil)

Mostrando recursos 1 - 20 de 154

  1. A Framework to Measure the Socio-Economic Impact of Development Programs Using Malmquist Index

    Devaraj, H
    The main objective of this research is to evaluate the socio economic impact of the development programs like MGNREGA, JnNURM and development of Roads project, on the intended target area. The entire thesis can be divided in to two parts; (1) developing method to evaluate the socio economic impact assessment and (2) case studies. Two different techniques were used to evaluate the change in the productivity. Initially the change is measure by calculating the difference in the efficiencies between two time period using base period and current period production technologies. To illustrate this method a case study of MGNREGA has...

  2. Elastic Wave Propagation and Evaluation of Low Strain Dynamic Properties in Jointed Rocks

    Sebastian, Resmi
    When the point under consideration is not near to the source of vibration, the strains developed in the rock mass due to the passage of waves are usually of small magnitude, and within the elastic range. However, the rock mass may be subjected to a wide range of strain levels depending on the source of vibration and the wave frequency, even within the elastic limit. The present study is based on the two general conditions existing at field, long wave length propagation of waves and intermediate wavelength propagation of waves. When the wavelength of propagating wave is much longer than...

  3. Characterization of Different Slags for Bulk Geotechnical Applications

    Logeshwari, J
    Generation of wastes in the form of liquid, solid or gas is inevitable in any industry.Industrial Solid Waste is the waste that is generated from an industrial or manufacturing process and includes the waste generated from non-manufacturing activities as well.Most of these wastes fall under the category of Ashes, Slagsor Sludges. For the present work, three types of secondary lead slag, two types of granulated blast furnace slag (GBS) or iron slag and four types of steel slags were procured and studied.An elaborate study on various characteristics of the slags has been performed. Based on the results, all the possible...

  4. Quantification of Uncertainties in Urban Precipitation Extremes

    Chandra Rupa, R
    Urbanisation alters the hydrologic response of a catchment, resulting in increased runoff rates and volumes, and loss of infiltration and base flow. Quantification of uncertainties is important in hydrologic designs of urban infrastructure. Major sources of uncertainty in the Intensity Duration Frequency (IDF) relationships are due to insufficient quantity and quality of data leading to parameter uncertainty and, in the case of projections of future IDF relationships under climate change, uncertainty arising from use of multiple General Circulation Models (GCMs) and scenarios. The work presented in the thesis presents methodologies to quantify the uncertainties arising from parameters of the distribution...

  5. Estimation of Daily Actual Evapotranspiration using Microwave and Optical Vegetation Indices for Clear and Cloudy Sky Conditions

    Rangaswamy, Shwetha Hassan
    Evapotranspiration (ET) is a significant hydrological process. It can be studied and estimated using remote sensing based methods at multiple spatial and temporal scales. Most commonly and widely used remote sensing based methods to estimate actual evapotranspiration (AET) are a) methods based on energy balance equations, b) vegetation coefficient based method and c) contextual methods. These three methods require reflectance and land surface temperature (LST) data measured at optical and thermal portion of the electromagnetic spectrum. However, these data are available only for clear sky conditions and fail to be retrieved under overcast conditions creating gaps in the data, which...

  6. Shape Characterization of Granular Particles using Image Based Techniques

    Roy, Nimisha
    Granular soils with different sizes and shapes are often used in many civil engineering structures. In different contexts, several researchers have emphasized that shape of particles play a pivotal role in influencing several engineering properties such as maximum and minimum packing densities, shear strength, permeability and compressibility. However, the complexities involved in obtaining the geometrical parameters necessary to adequately compute particle shape have hampered the clear understanding of the contribution of particle shape to such properties. Researchers have attempted to characterize the shape of the particles by many conventional and advanced image based methods in the past. However, these methods...

  7. Modelling Evapotranspiration from Satellite Data using semi-empirical Models : Applications to the Indian Subcontinent

    Eswar, R
    The major aim of this work is to develop a framework for the estimation of Evapotranspiration (ET) over the Indian landmass using remote sensing (RS) datasets in a repeated and consistent manner with improved spatial resolution. Different RS based ET models exist in the literature, out of which, the triangle, the S-SEBI and the Sim-ReSET models were compared for the estimation of daytime integrated latent heat flux (λEday). These three models were chosen as they can be driven only with RS based inputs without the need for any ground measurements. The results showed that the application of simpler contextual models...

  8. Multi-scale Modeling of Nanoparticle Transport in Porous Media : Pore Scale to Darcy Scale

    Seetha, N
    Accurate prediction of colloid deposition rates in porous media is essential in several applications. These include natural filtration of pathogenic microorganisms such as bacteria, viruses, and protozoa, transport and fate of colloid-associated transport of contaminants, deep bed and river bank filtration for water treatment, fate and transport of engineered nanoparticles released into the environment, and bioremediation of contaminated sites. Colloid transport in porous media is a multi-scale problem, with length scales spanning from the sub-pore scale, where the particle-soil interaction forces control the deposition, up to the Darcy scale, where the macroscopic equations governing particle transport are formulated. Colloid retention...

  9. Studies on Fracture and Fatigue Behavior of Cementitious Materials- Effects of Interfacial Transition Zone, Microcracking and Aggregate Bridging

    Keerthy, M Simon
    The microstructure of concrete contains random features over a wide range of length scales in which each length scale possess a new random composite. The influence of individual material constituents at different scales and their mutual interactions are responsible for the formation of fracture process zone (FPZ). The presence of the FPZ and the various toughening mechanism occurring in it, influences the fatigue and fracture behavior of concrete which also gets influenced by the geometry, spacial distribution and material properties of individual material constituents and their mutual interactions. Hence, in order to study the influence of interfacial transition zone, microcrack...

  10. Endochronic Constitutive Model for Sands and Its Application to Geotechnical Problems

    Raji, M
    The introductions of large digital computers in the field of engineering have rendered possible the solution of a wide variety of problems without the need to violate the equilibrium and compatibility. The major requirement for such analysis is a good constitutive model that represents the stress strain behaviour of the materials in an accurate way. Nowadays for most of the geotechnical engineering applications the elastoplastic models like Mohr Coulomb model are widely used. All the existing constitutive models which represent the plastic behaviour of soil are developed from the fundamentals of classical theory of plasticity. The classical theory of plasticity...

  11. Studies on Propagating and Non-Propagating Cracks in Concrete Under Fatigue Loading in the Short Crack Regime

    Abraham, Nimmy Mariam
    Structural concrete is the most widely used material in the construction of bridges, pave-ments, runways, dams and other infrastructures which are subjected to uctuating loads during its service period. Concrete contains internal aws in the form of micro-cracks as an inherent property. When subjected to fatigue loading, distributed micro-cracks are formed at the sites of pre-existing aws, which subsequently, localize to form a major crack and propagates. The crack growth curve of a structural component when subjected to fatigue loading depicts a sigmoidal pattern. This curve is divided into three distinct regions namely sub-threshold crack propagation (short crack), stable crack...

  12. Monte Carlo Simulations with Variance Reduction for Structural Reliability Modeling, Updating and Testing

    Sundar, V S
    Monte Carlo simulation techniques have emerged as widely accepted computing tools in tackling many problems in modern structural mechanics. Apart from developments in computational hardware, which have undoubtedly made simulation strategies practically feasible, the success of Monte Carlo simulations has also resulted equally significantly from the methodological developments aimed at controlling sampling variance of the Monte Carlo estimates. The study reported in the present thesis is aimed at developing and validating Monte Carlo simulation based approaches with inbuilt variance reduction capabilities to deal with problems of time variant reliability modeling, random vibration testing, and updating reliability models for statically/dynamically loaded...

  13. Frequency Analysis of Floods - A Nanoparametric Approach

    Santhosh, D
    Floods cause widespread damage to property and life in different parts of the world. Hence there is a paramount need to develop effective methods for design flood estimation to alleviate risk associated with these extreme hydrologic events. Methods that are conventionally considered for analysis of floods focus on estimation of continuous frequency relationship between peak flow observed at a location and its corresponding exceedance probability depicting the plausible conditions in the planning horizon. These methods are commonly known as at-site flood frequency analysis (FFA) procedures. The available FFA procedures can be classified as parametric and nonparametric. Parametric methods are based...

  14. Modeling Salinity Impact on Ground Water Irrigated Turmeric Crop

    Kizza, Teddy
    Soils in irrigated fields are impacted by irrigation water quality. Salts in the irrigation water may accumulate in the soil depending on amount of leaching, the quality of water and type of ions present. Salinity is an environmental hazard that is known to limit agriculture worldwide. The quality of irrigation water is thus of concern to agriculturists. More so is the impact it has on productivity. The objective of this study was to quantify the impact due to use of ground water of such quality, with respect to salinity, as found in Berambadi watershed of Southern India, under farmers‟ field...

  15. Hydrologic Response of Upper Ganga Basin to Changing Land Use and Climate

    Chawla, Ila
    Numerous studies indicate that the hydrology of a river basin is influenced by Land Use Land Cover (LULC) and climate. LULC affects the quality and quantity of water resources through its influence on Evapotranspiration (ET) and initiation of surface runoff while climate affects the intensity and spatial distribution of rainfall and temperature which are major drivers of the hydrologic cycle. Literature reports several works on either the effect of changing LULC or climate on the hydrology. However, changes in LULC and climate occur simultaneously in reality. Thus, there is a need to perform an integrated impact assessment of such changes...

  16. Role of Composition, Structure and Physico-Chemical Environment on Stabilisation of Kuttanad Soil

    Suganya, K
    Soft soil deposits of coastal regions and lowland areas pose many geotechnical problems but it is indispensable to utilize these grounds to meet the growing demand for infrastructure with ever increasing urbanization and industrial development. Soft soils are generally associated with high compressibility and low strength characteristics which augment the risk of huge settlements and foundation failure. It is essential to understand the complex behaviour of the ground consisting of soft clays as construction and maintenance of infrastructure in these areas is challenging. Marine sediments mostly possess open microstructure irrespective of the differences in their mineral composition and sedimentation environment....

  17. Characterization and Assessment of Organically Modified Clays for Geo Environmental Applications

    Sreedharan, Vandana
    Clays are used for long for the control of soil and water pollution as they are inexpensive natural materials with a high adsorption capacity for a wide range of pollutants. However their use as components in engineered waste containment systems is often limited when it comes to the control of organic contaminants as the clays are organophobic in nature. Organic modification of the natural clays, by replacing the exchangeable inorganic cations of clay with organic cations, can facilitate to overcome this limitation. On modification the clays become organophilic which can enhance their sorption capacities for organic contaminants. There are several...

  18. Influence of Permeation of Synthetic Groundwater Solutions on the Hydro-Mechanical Proerties of Barmer Bentonite

    Shashidhar, S
    The deep geological repository concept is based on “engineered barriers systems (EBS)” that are constructed in the repository and “natural barriers” provided by the surrounding geological environment. The EBS comprises of variety of sub-systems or components, such as the waste form, canister, buffer, backfill, seals, and plugs. Geological disposal is based on the concept of multiple barriers that work together to provide containment. The buffer is made up of densely compacted bentonite or bentonite-sand mix. Bentonite has both mechanical and physico-chemical functions, to fulfill as a barrier material in DGR. The bentonite buffer should hold the containers in place and...

  19. Strength and Deformation Behavior of Municipal Solid Waste (MSW) Based on Constitutive Modeling Approach

    Chouksey, Sandeep Kumar
    The geotechnical properties of municipal solid waste (MSW) such as compressibility, shear strength and stiffness are of prime importance in design and construction of landfills. However, it is not well clear how the stress-strain and strength characteristics vary with time as the biodegradation of waste continues in the landfill. There is also a need to address the variability of MSW properties and their role in landfill design. The present thesis proposes models for the analyses of stress-strain response of MSW in undrained and drained conditions. The proposed models are based on critical state soil mechanics concept and the modified cam...

  20. Predictability of Nonstationary Time Series using Wavelet and Empirical Mode Decomposition Based ARMA Models

    Lanka, Karthikeyan
    The idea of time series forecasting techniques is that the past has certain information about future. So, the question of how the information is encoded in the past can be interpreted and later used to extrapolate events of future constitute the crux of time series analysis and forecasting. Several methods such as qualitative techniques (e.g., Delphi method), causal techniques (e.g., least squares regression), quantitative techniques (e.g., smoothing method, time series models) have been developed in the past in which the concept lies in establishing a model either theoretically or mathematically from past observations and estimate future from it. Of all...

Aviso de cookies: Usamos cookies propias y de terceros para mejorar nuestros servicios, para análisis estadístico y para mostrarle publicidad. Si continua navegando consideramos que acepta su uso en los términos establecidos en la Política de cookies.