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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

AN EXPERIMENTAL STUDY OF THE RESPONSE OF REINFORCED CONCRETE FRAMES WITH WOOD PANEL INFILLS TO SIMULATED EARTHQUAKES

Charles Skehan Kerby (12446373) 22 April 2022 (has links)
<p>Masonry infills historically have increased in-plane stiffness and reduced drift demands of reinforced concrete frames. An inherent risk remains during intense ground motions that unreinforced masonry infills can develop shear cracks, fail out-of-plane, or lead to the formation of captive-column conditions. This study explored the use of full-bay, plywood panel infills in non-ductile reinforced concrete frames as a novel seismic retrofit. Wood infills were constructed from layers of APA 3/4” Rated Sheathing plywood panels. Infills were tested using two single-bay, single-story concrete frames at 1/3 scale, with initial periods between 0.1 and 0.3 seconds once infilled. External post-tensioning was provided to the columns during all series to prevent column shear failure and doubled as dowel connections between the concrete frame and wood panel infill. Test series were performed on a uniaxial earthquake simulator with the frame bay parallel to the direction of ground motion. Wood infills were approximately 0.36∗𝑏, 0.18∗𝑏, and 0.09∗𝑏 thick, where b is the column width. Multi-layer infills were screw-laminated via a 6” square grid. Infills were tested in previously damaged and nominally pristine frames.</p> <p>During similar ground motions, masonry infills reduced the effective period of the pristine bare frame by approximately 50%. In nominally pristine frames, one-panel plywood infills reduced the bare frame period by a maximum of 50%, and two-panel infills by 60%. One and two-panel wood infills reduced drift demands in comparison to the pristine bare frame by a factor of 1√2∗𝑛 in previously damaged frames and by 12∗𝑛 in nominally pristine frame, where n is the number of panels of plywood across the infill thickness. There was no extra reduction in drift demands resulting from increasing the wood infill thickness beyond two panels. One-panel wood infills failed via out-of-plane buckling causing splitting at a drift demand of approximately 1.5%.</p> <p>The results of this study confirm that wood panel infill retrofits are structurally viable alternatives to stiffen non-ductile reinforced concrete frames. Plywood panel infills reduced drift demands more efficiently per unit thickness and unit weight than masonry infills; the resilience and ease of construction of wood infills suggest expanded use should be explored. Experimental study of full-scale wood infills is needed before this retrofit method could become field deployable.</p>
182

Bayesian Identification of Nonlinear Structural Systems: Innovations to Address Practical Uncertainty

Alana K Lund (10702392) 26 April 2021 (has links)
The ability to rapidly assess the condition of a structure in a manner which enables the accurate prediction of its remaining capacity has long been viewed as a crucial step in allowing communities to make safe and efficient use of their public infrastructure. This objective has become even more relevant in recent years as both the interdependency and state of deterioration in infrastructure systems throughout the world have increased. Current practice for structural condition assessment emphasizes visual inspection, in which trained professionals will routinely survey a structure to estimate its remaining capacity. Though these methods have the ability to monitor gross structural changes, their ability to rapidly and cost-effectively assess the detailed condition of the structure with respect to its future behavior is limited.<div>Vibration-based monitoring techniques offer a promising alternative to this approach. As opposed to visually observing the surface of the structure, these methods judge its condition and infer its future performance by generating and updating models calibrated to its dynamic behavior. Bayesian inference approaches are particularly well suited to this model updating problem as they are able to identify the structure using sparse observations while simultaneously assessing the uncertainty in the identified parameters. However, a lack of consensus on efficient methods for their implementation to full-scale structural systems has led to a diverse set of Bayesian approaches, from which no clear method can be selected for full-scale implementation. The objective of this work is therefore to assess and enhance those techniques currently used for structural identification and make strides toward developing unified strategies for robustly implementing them on full-scale structures. This is accomplished by addressing several key research questions regarding the ability of these methods to overcome issues in identifiability, sensitivity to uncertain experimental conditions, and scalability. These questions are investigated by applying novel adaptations of several prominent Bayesian identification strategies to small-scale experimental systems equipped with nonlinear devices. Through these illustrative examples I explore the robustness and practicality of these algorithms, while also considering their extensibility to higher-dimensional systems. Addressing these core concerns underlying full-scale structural identification will enable the practical application of Bayesian inference techniques and thereby enhance the ability of communities to detect and respond to the condition of their infrastructure.<br></div>
183

Seismic Analysis of Norra Tornen : A Comparison Based on the Requirements in Eurocode 8

Barbaranelli, Andreas, Wallin, Andreas January 2019 (has links)
In Sweden, buildings are not designed to withstand earthquakes due to the rarity of an earthquake event and its consequential damage. However, the aim of this thesis was to study the seismic performance of some of the highest buildings in Stockholm, called Innovationen and Helix. The purpose of the study was to get an understanding of earthquake engineering for high rise buildings and to compare the behavior of the two towers during seismic action. In order to compare the two buildings and get an understanding of what will affect the seismic performance, Eurocode 8 was used. The Eurocode standard lists several properties that impacts the seismic resistance of buildings. One of the goals was to study how those factors influence the behavior of Innovationen and Helix and finally compare the results to each other in order to draw valid conclusions. The method to perform the analysis was a modal analysis using a finite element analysis program. The program used contains predefined response spectra’s based on Eurocode 8 which is used to define the seismic load acting on the structures. The extracted results are listed below: - Frequencies and mode shapes - Modal masses - Level and total masses - Accelerations - Displacements The conclusion of the study was that Innovationen and Helix have similar properties and some points from Eurocode 8 were better fulfilled by Helix and others by Innovationen: - Uniformity, symmetry and redundancy (Innovationen fulfills the requirements better than Helix) - Bi-directional resistance and stiffness (Innovationen fulfills the requirements better than Helix) - Torsional resistance and stiffness (Helix fulfills the requirements better than Innovationen) - Adequate foundation (Helix fulfills the requirements better than Innovationen) Of the two parameters studied, the height was the one with the most influence on seismic resistance.
184

Parametric Study of Self-Centering Concentrically-Braced Frames with Friction-Based Energy Dissipation

Jeffers, Brandon 15 May 2012 (has links)
No description available.
185

Seismic Retrofit of Reinforced Concrete Frame Buildings with Tension Only Braces

Khosravi, Sadegh 13 October 2021 (has links)
Reinforced concrete buildings built prior to the enactment of modern seismic codes are often seismically deficient. These buildings may have inadequate strength and ductility to withstand strong earthquakes. Conventional retrofit techniques for such frame buildings involve adding reinforced concrete shear walls or structural bracing systems to the existing bays. These techniques can be intrusive and result in lengthy down times and expensive structural interventions. An alternative to conventional techniques is the use of high-strength prestressing strands or cables, diagonally placed as tension elements. This technique was researched and used in a limited manner after the 1985 Mexico City Earthquake. It has since been further investigated at the University of Ottawa through experimental and analytical research (Shalouf and Saatcioglu (2006), Carrière (2008), Molaei (2014)). While the use of steel strands as tension bracing elements proves to be an effective technique, the resulting stiffening effects on the frames lead to increased seismic force demands and higher based shear, as well as increased axial forces on the attached columns, potentially generating net tension, foundation uplift and excessive compression. Relatively low elongation characteristics of high-strength cables and slack caused by yielding strands and associated pinching of hysteresis curves reduce potential energy dissipation capacity. The current research aims to improve the previously observed deficiencies of the system. One of the improvements involve the use of shape memory alloys (SMA) in the middle of the cables, which reduce/eliminate residual deformations upon yielding and associated pinching of the hysteresis curves. SMA allows energy dissipation in the system while forcing the structure to recover from its inelastic deformations because of the flag-shape hysteretic characteristics of the material. The feasibility of the cable-SMA assembly as tension brace elements is illustrated through dynamic analyses of selected prototype buildings. The other improvement is the development of progressively engaging, initially loose multiple strands as tension cables. These cables are placed loosely to engage in seismic resistance at pre-determined drift levels, thereby eliminating premature increase in seismic force demands until their participation is required as the frame capacity is reached. Tests of a large-scale reinforced concrete frame, designed following the requirements of the 1965 National Building Code of Canada NRC (1965) as representative of existing older frame buildings in Canada, are conducted under simulated seismic loading to assess the effectiveness of the proposed system. The verification of the concept is extended analytically to prototype buildings and the effectiveness of the system is demonstrated for mid-rise and low-rise frame buildings.
186

Simulation, Analysis and Design of Systems with Multiple Seismic Support Motion

Nizamiev, Kamil 13 September 2016 (has links)
No description available.
187

SYSTEM-LEVEL SEISMIC PERFORMANCE OF CONCENTRICALLY BRACED FRAMES WITH REPLACEABLE BRACE MODULES

Mohsenzadeh, Vahid January 2020 (has links)
Concentrically braced frames with replaceable brace modules (RBMs) have the potential of improving the constructability of braced frames, mitigating the structural damage during earthquakes, and minimizing the time of post-earthquake repairs. To fill the gaps between the component-level performance of RBMs and system-level behaviour of SCBFs with RBMs, this thesis focused on the overall system-level seismic performance of SCBFs with RBMs in three steps. Firstly, the effects of beam-column connection fixity on the behaviour of three SCBFs were investigated to determine what level of fixity, if any, is required to ensure adequate collapse capacity of an SCBF. Secondly, the effects of column design parameters on braced frame seismic performance were investigated, where two different brace-to-frame connections were considered: 1) conventional gusset plate connection and 2) the newly proposed connection detail with RBMs. Detailed numerical modelling was undertaken to develop improved provisions for designing columns in SCBFs. Finally, a large-scale experimental program was conducted to evaluate the seismic performance of braced frames with initial and replaced RBMs where realistic boundary conditions were provided. Three different beam-column connections that can be used in SCBFs with RBMs were designed and tested. Based on the current work, the recently proposed concept of replaceable brace modules, accompanied by the recommended methods for designing columns and detailing beam-column connections, appears to be a promising approach. The fabrication and installation are simpler, the seismic performance is similar to that of SCBFs with currently accepted connection detailing, and the approach can increase the post-earthquake reparability of steel concentrically braced frames. / Dissertation / Doctor of Philosophy (PhD)
188

Análisis y diseño comparativo entre un edificio con amortiguadores de masa sintonizada y un edificio convencional en la ciudad de Chiclayo

Llontop Izquierdo, Kevin Antonio January 2023 (has links)
Perú está ubicado en uno de los continentes que presentan mayor actividad sísmica causando muchas pérdidas humanas y daños excesivos en elementos estructurales y no estructurales, así mismo para disminuir estos movimientos sísmicos se ha estudiado un sistema de protección sísmica llamado Amortiguamiento de masa sintonizada con el fin de aumentar el desempeño sísmico, El edificio analizado es: las dos torres de Salaverry ubicado en la ciudad de Chiclayo del territorio Peruano, Dicho amortiguamiento de masa sintonizada se ha colocado en la parte final del edifico con el propósito de disminuir los desplazamientos laterales ,Los Análisis utilizados han sido el Estatico,Dinamico Y el Análisis tiempo historia cumpliendo también con los requisitos de la Norma E030 , Para el análisis tiempo historia se han seleccionado los sismos ocurridos en Piura el 18 de octubre de 2021 y el 3 de febrero Condorcanqui Amazonas y uno de los sismos más fuertes de Perú que es de lima 1974, de los resultados obtenidos se ha concluido que este sistema de amortiguamiento de masas sintonizada al incorporar a edificios reduce considerablemente los desplazamientos laterales, resultando ser uno de sistemas de protección sísmica favorable / Peru is located in one of the continents that present the greatest seismic activity, causing many human losses and excessive damage to structural and non-structural elements. Likewise, in order to reduce these seismic movements, a seismic protection system called Tuned mass damping has been studied in order to increase the seismic performance, The analyzed building is the two Salaverry towers located in the city of Chiclayo in the Peruvian territory, This tuned mass damping has been placed in the final part of the building with the purpose of reducing lateral displacements, The Analyzes used have been the Static, Dynamic and Time History Analysis, also complying with the requirements of Standard E030. For the time history analysis, the earthquakes that occurred in Piura on October 18, 2021 and February 3, Condorcanqui Amazonas and one of the strongest earthquakes in Peru, which is from Lima 1974, of the results obtained It has been concluded that this tuned mass damping system when incorporated into buildings considerably reduces lateral displacements, turning out to be one of the favorable seismic protection systems.
189

Assessment of linear and static procedures for performance-based seismic evaluation of structures

Friis, Donna Lisa Renate 01 October 2001 (has links)
No description available.
190

Site Characterization and Assessment of Various Earthquake Hazards for Micro and Micro-Level Seismic Zonations of Regions in the Peninsular India

James, Naveen January 2013 (has links) (PDF)
Past earthquakes have demonstrated that Indian sub-continent is highly vulnerable to earthquake hazards. It has been estimated that about 59 percent of the land area of the Indian subcontinent has potential risk from moderate to severe earthquakes (NDMA, 2010). Major earthquakes in the last 20 years such as Khillari (30th September 1993), Jabalpur (22nd May 1997), Chamoli (29th March 1999) and Bhuj (26th January 2001) earthquakes have resulted in more than 23,000 deaths and extensive damage to infrastructure (NDMA, 2010). Although it is well known that the major earthquake hazard prone areas in India are the Himalayan region (inter-plate zone) and the north-east region, (subduction zone) the seismicity of Peninsular India cannot be underestimated. Many studies (Seeber et al., 1999; Rao, 2000; Gangrade & Arora, 2000) have proved that the seismicity of Peninsular India is significantly high and may lead to earthquakes of sizeable magnitude. This necessitates a seismic zonation for the country, as well as various regions in it. Seismic zonation is the first step towards an effective earthquake risk mitigation study. Seismic zonation is a process in which a large region is demarcated into small zones based on the levels of earthquake hazard. Seismic zonation is generally carried out at three different levels based on the aerial extent of the region, importance of site and the population. They are micro-level, meso-level and macro-level. The macro-level zonation is generally carried out for large landmass such as a state or a country. The earthquake hazard parameters used for macro-level zoning are generally evaluated with less reliability. The typical example of a macro-level zonation is the seismic zonation map of India prepared by BIS-1893 (2002), where the entire India is demarcated into four seismic zones based on past seismicity and tectonic conditions. Generally the macro-level seismic zonation is carried out based on peak horizontal acceleration (PHA) estimated at bedrock level without giving emphasis on the local soil conditions. Seismic zonation at the meso-level is carried out for cities and urban centers with a population greater than 5,00,000. The earthquake hazard parameters, for the meso-level zonation are evaluated with greater degree of reliability, compared to the macro-level zoning. The micro-level zonation is carried out for sites which host critical installations such as nuclear power plants (NPPs). As the NPPs are considered as very sensitive structures, the earthquake parameters, for the micro-level zonation of the NPP sites are estimated with a highest degree of reliability. The local soil conditions and site effects are properly counted for carrying out the micro as well as the meso-level zonation. Several researchers have carried out meso-level zonation considering effects of all major earthquake hazards such as PHA, site amplification, liquefaction (Mohanty et al., 2007; Nath et al., 2008; Sitharam & Anbazhagan, 2008 etc.) Even though the above definitions and descriptions are available for various levels of zonation, the key issue lies in the adoption of the suitable one for a given region. There are only a few guidelines available regarding the use of a particular level of zonation for a given study area. Based on the recommendation of the disaster management authority, the government of India has initiated the seismic zonation of all major cities in India. As it is evident that large resources are required in order to carry out seismic site characterization and site effect estimation, both the micro and meso-level zonations cannot be carried out for all these cities. Hence there is a need to propose appropriate guidelines to define the suitability of each level zonation for various re-gions in the country. Moreover there are many methodologies available for site characterization and estimation of site effects such as site amplification and liquefaction. The appropriateness of these methodologies for various levels of seismic zonations also needs to be assessed in order to optimize use of resources for seismic zonation. Hence in the present study, appropriate techniques for site characterization and earthquake hazard estimation for regions at different scale levels were determined. Using the appropriate techniques, the seismic zonation was carried out both at the micro and macro-level, incorporating all major earthquake hazards. The state of Karnataka and the Kalpakkam NPP site were chosen for the macro and micro−level seismic zonation in this study. Kalpakkam NPP site is situated in Tamil Nadu, India, 70 kilometres south of Chennai city. The NPP site covers an area of 3000 acres. The site is situated along the Eastern coastal belt of India known as Coromandel coast with Bay of Bengal on the east side. The NPP site host major facilities such as Indira Gandhi Centre for Atomic Research (IGCAR), Madras Atomic Power Station (MAPS), Fast Reactor Fuel Reprocessing (FRFC) Plant, Fast Breeder Test Reactor (FBTR), Prototype Fast Breeder Reactor (PFBR) etc. The state Karnataka lies in the southern part of India, covering an area of 1,91,791 km2, thus approximately constituting 5.83% of the total geographical area of India. Both the study areas lie in the Indian Peninsular which is identified as one of the most prominent and largest Precambrian shield region of the world. The first and foremost step towards the seismic zonation is to prepare a homogenised earthquake catalogue. All the earthquake events within 300 km radius from the boundary of two study areas were collected from various national and international agencies. The earthquake events thus obtained were found to be in different magnitude scales and hence all these events were converted to the moment magnitude scale. A declustering procedure was applied to the earthquake catalogue of the two study area in order to remove aftershocks, foreshocks and dependent events. The completeness analysis was carried out and the seismicity parameters for the two study areas were evaluated based on the complete part of earthquake catalogues. The next major step toward the estimation of earthquake hazard and seismic zonation is the identification and mapping of the earthquake sources. Three source models, mainly; 1) linear source model, 2) point source model and 3) areal source model were used in the present study for characterizing earthquake sources in the two study areas. All the linear sources (faults and lineaments) within 300 km radius from the boundary of two study areas were identified and mapped from SEISAT (2000). In addition to SEISAT (2000), some lineaments were also mapped from the works of Ganesha Raj & Nijagunappa (2004). These lineaments and faults were mapped and georeferenced in a GIS platform on which earthquake events were then super-imposed to give seismotectonic atlas. Seismotectonic atlas was prepared for both the study areas. The point source model (Costa et al. 1993; Panza et al. 1999) and areal source model (Frankel, 1995) were also adopted in this work. Deterministic and probabilistic seismic hazard analysis was found to be appropriated for micro, meso and macro-level zonations. Hence in the present study, the seismic hazard at bedrock level, both at the micro and macro-level were evaluated using the deterministic as well as the probabilistic methodologies. In order to address the epistemic uncertainties in source models and attenuation relations, a logic tree methodology was incorporated with the deterministic and probabilistic approaches. As the deterministic seismic hazard analysis (DSHA) considers only the critical scenario, knowing the maximum magnitude that can occur at a source and the shortest distance between that source and the site and the peak horizontal acceleration (PHA) at that site is estimated using the frequency dependent attenuation relation. Both for the micro as well as the macro-level, the DSHA was carried out, considering grid sizes of 0.001◦ × 0.001◦ and 0.05◦ × 0.05◦respectively. A MATLAB program was developed to evaluate PHA at the center of each of these grid points. The epistemic uncertainties in source models and attenuation relations have been addressed using a logic tree approach (Bommer et al., 2005). A typical logic tree consists of a series of nodes to which several models with different weightages are assigned. Allotment of these weightages to different branch depends upon the degree of uncertainties in the model, and its accuracy. However the sum of all weightages of different branches at a particular node must be unity. Two types of seismic sources are employed in DSHA and they are linear and smoothed point sources. Since both the types of sources were of equal importance, equal weightages were assigned to each of them. The focal depth in the present study was taken as 15 km. The attenuation properties of the region were modelled using three attenuation relations, Viz. Campbell & Bozorgnia (2003), Atkinson & Boore (2006) and Raghu Kanth & Iyengar (2007). The attenuation relation proposed by Raghu Kanth & Iyengar (2007) was given higher weightage of 0.4 since it was devel-oped for the Indian peninsular region. The attenuation relations by Atkinson & Boore (2006) and Campbell & Bozorgnia (2003) which were developed for Eastern North American shield region, shared equal weightages of 0.3. Maps showing spatial variation of PHA value at bedrock level, for both micro and macro-level are presented. Response spectra at the rock level for important location in the two study areas were evaluated for 8 different periods of oscillations, and the results are presented in this thesis. Probabilistic seismic hazard analysis (PSHA) incorporating logic tree approach was per-formed for both micro as well as macro-level considering similar grid sizes as in DSHA. Two types of seismic sources considered in the PSHA are linear sources and smoothed gridded areal sources (Frankel, 1995) with equal weightage distribution in the logic tree structure. Smoothed gridded areal sources can also account the scattered earthquake events. The hypocentral distance was calculated by considering a focal depth of 15 km, as in the case of DSHA method. A MAT-LAB program was developed for PSHA. The same attenuation relations employed in DSHA were used in PSHA as well with the same weightage allotment in logic tree structure. Considering all major uncertainties, a uniform hazard response spectrum (UHRS), showing the variation of PHA values with the mean annual rate of exceedance (MARE), was evaluated for each grid point. From the uniform hazard response spectrum, the PHA corresponding to any return period can be evaluated. Maps showing the spatial variation of PHA value at bedrock level, corresponding to 475 year and 2500 year return periods for both micro and macro-level are presented. Response spectra at the rock level for important location in two study areas were evaluated for eight different periods of oscillations, and the results are presented in this thesis. In order to assess various earthquake hazards like ground motion amplification and soil liquefaction, a thorough understanding of geotechnical properties of the top overburden soil mass is essential. As these earthquake hazards strongly depend on the geotechnical properties of the soil, site characterization based on these properties will provide a better picture of these hazards. In the present study, seismic site characterization was carried both at the micro and macro-level using average shear wave velocity for top 30 m overburden (Vs30). At the micro-level, the shear wave velocity profile at major locations was evaluated using multichannel analysis of surface waves (MASW) tests. MASW is an indirect geophysical method used in geotechnical investigations and near surface soil characterization based on the dispersion characteristics of surface waves (Park et al., 1999). The MASW test setup consists of 24-channel geophones of 4.5 Hz capacity. A 40 kg propelled energy generator (PEG) was used for generating surface wave. Based on the recordings of geophones, the dispersion characteristics of surface waves were evaluated in terms of a dispersion curve. The shear wave velocity (Vs) profile at a particular location was determined by performing inversion analysis (Xia et al., 1999). After the evaluation of V s profile at all major locations, the site characterization at the micro-level was carried out as per NEHRP (BSSC, 2003) and IBC (2009) recommendations. Maps showing the spatial distribution of various site classes at the micro-level are presented in this thesis. Standard penetration tests were also carried out in the site as part of subsurface investigation and in this study a new correlation between V s and corrected SPT-N values was also developed. Apart from carrying out site characterization, low strain soil stiffness profile was evaluated based on SPT and MASW data. In this work, seismic site characterization at the macro-level was also carried out. As it is not physically and economically viable to carry out geotechnical and geophysical testing for such a large area, like the Karnataka state, the seismic site characterization was carried out based on topographic slope maps. Wald & Allen (2007) has reported that the topographic slope is a perfect indicator of site conditions. Based on the correlation studies carried out for different regions, Wald & Allen (2007) has proposed slope ranges corresponding to each site class. In this study, the topographic map for the entire state of Karnataka was derived from ASTER Global Digital Elevation Model GDEM. This thesis also presents a comparison study between the Vs30map generated from topographic slope data and Vs30map developed using geophysical field tests, for Bangalore and Chennai. Based on this study, it is concluded that topographic slopes can be used for developing Vs30maps for meso and macro-level with reasonable accuracy. The topographic map for macro-level was generated at a grid size of 0.05◦ × 0.05◦. Based on the value of slope at a particular grid point, the Vs30for that grid point was assigned as per Wald & Allen (2007). A similar procedure was repeated for all the grid points. Spatial variation of various seismic site classes for the macro-level has been presented in this work. The site amplification hazard was estimated for both micro and the macro-level. The assessment of site amplification is very important for shallow founded structures and other geotechnical structures like retaining walls and dams, floating piles and underground structures as the possible earthquake damages are mostly due to extensive shaking. The site amplification hazard at the micro-level was estimated using 1D equivalent linear ground response analyses. The earthquake motion required for carrying out ground response analysis was simulated from a target response spectrum. 1D equivalent linear analyses were performed using SHAKE 2000 software. Spatial variations of surface level PHA values, site amplification, predominant frequency throughout the study area are presented in this work. As it is not physically viable to assess site amplification hazard at the macro-level using the 1D ground response analysis, the surface level PHA value for the entire state of Karnataka was estimated using a non-linear site amplification technique pro-posed by Raghu Kanth & Iyengar (2007). Based on the site class in which particular grid belongs and bedrock level PHA value, the amplification for that grid point was evaluated using regression equations developed by Raghu Kanth & Iyengar (2007). The liquefaction hazard both at the micro and macro-level was evaluated and included in this thesis. The micro-level liquefaction hazard was estimated in terms of liquefaction potential index (LPI) based on SPTN values (Iwasaki et al., 1982). As the LPI was evaluated by integrating the factor of safety against liquefaction (FSL) at all depths, it can effectively represent the liquefaction susceptibility of the soil column. LPI at the micro-level was evaluated by both deterministic as well as the probabilistic approaches. In the deterministic approach, the FSLat a particular depth was evaluated as the ratio of the cyclic resistance of the soil layer to the cyclic stress induced by earth-quake motion. The cyclic stress was estimated as per Seed & Idriss (1971), while the cyclic soil resistance was characterised from the corrected SPT-N values as proposed by Idriss & Boulanger (2006). However in the probabilistic method, the mean annual rate of exceedance (MARE) of factor of safety against liquefaction at different depth was estimated using SPT field test data by considering all uncertainties. From the MARE curve, the FS L for 475 year and 2500 year return period were evaluated. Once FS L at different depth were evaluated, the LPI for the borehole is calculated by integrating FS L for all depths. The liquefaction hazard at the macro-level was estimated in terms of SPT and CPT values required to prevent liquefaction at 3 m depth, using a probabilistic approach. The probabilistic approach accounts the contribution of several magnitudes acceleration scenarios on the liquefaction potential at a given site. Based on the methodology proposed by Kramer & Mayfield (2007), SPT and CPT values required to resist liquefaction corresponding to return periods of 475 years and 2500 years were evaluated at the macro-level. It has been observed that the spatial distribution of intensity of each these hazard in a region is distinct from the other due to the predominant influence of local geological conditions rather than the source characteristics of the earthquake. Hence it’ll be difficult to assess risk and vulnerability of a region when these hazards are treated separately. Thus, all major earthquake hazards are to be integrated to an index number, which effectively represents the combined effect of all hazards. In the present study, all major earthquake hazards were integrated to a hazard index value, both at the micro as well as macro-level using the Analytical Hierarchy Process (AHP) proposed by Saaty (1980). Both micro and macro-level seismic zonation was performed based on the spatial distribution of hazard index value. This thesis also presents the assessment of earthquake induced landslides at the macro-level in the appendix. Landslide hazards are a major natural disaster that affects most of the hilly regions around the world. This is a first attempt of it kind to evaluate seismically induced landslide hazard at the macro-level in a quantitative manner. Landslide hazard was assessed based on Newmark’s method (Newmark, 1965). The Newmark’s model considers the slope at the verge of failure and is modelled as a rigid block sliding along an incline plane under the influence of a threshold acceleration. The value of threshold acceleration depends upon the static factor of safety and slope angle. At the macro-level, the slope map for the entire state of Karnataka was derived from ASTER GDEM, considering a grid size of 50 m × 50 m. The earthquake motion which induces driving force on the slope to destabilize it was evaluated for each grid point with slope value 10 degree and above using DSHA. Knowing the slope value and peak horizontal acceleration (PHA) at a grid point, the seismic landslide hazard in terms of static factor of safety required to resist landslide was evaluated using Newmark’s method. This procedure is repeated for all grid points, having slope value 10 degree and above.

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