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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.
1

VISTA : a visual impact simulation technical aid

Fox, Peter J. N. January 1982 (has links)
No description available.
2

Building and Tree Parameterization in Partiallyoccluded 2.5D DSM Data / Byggnads- och träd- parametrisering i halvt skymda 2.5D digitala höjdmodeller

Källström, Johan January 2015 (has links)
Automatic 3D building reconstruction has been a hot research area; a task which has been done manually even up today. Automating the task of building reconstruction enables more applications where up to date information is of great importance. This thesis proposes a system to extract parametric buildings and trees from dense aerial stereo image data. The method developed for the tree identification and parameterization is a totally new approach which have yielded great results. The focus has been to extract the data in such a way that small flying platforms can use it for navigational purposes. The degree of simplification is therefor high. The building parameterization part starts with identifying roof faces by Region Growing random seeds in the digital surface model (DSM) until a coverage threshold is met.For each roof face a plane is fitted using a Least Square approach.The actual parameterization is started with calculating the intersection between the roof faces. Given the nature of 2.5D DSM data there is no possibility to perform wall fitting. Therefor all the walls will be constructed with a 2D line Hough transform of the border data of all the roof faces. The tree parameterization is done by searching for possible roof face topologies resembling the signature of a tree. For each possible tree topology a second degree polynomial surface is fitted to the DSM data covered by the faces in the topology. By looking at the parameters of the fitted polynomial it is then possible to determine if it is a tree or not. All the extraction steps were implemented and evaluated in Matlab, all algorithms have been described, discussed and  motivated in the thesis.
3

Quantitative Comparison of Lidar Data and User-generated Three-dimensional Building Models From Google Building Maker

Liu, Yang 08 1900 (has links)
Volunteered geographic information (VGI) has received increased attention as a new paradigm for geographic information production, while light detection and ranging (LiDAR) data is widely applied to many fields. This study quantitatively compares LiDAR data and user-generated 3D building models created using Google Building Maker, and investigate the potential applications of the quantitative measures in support of rapid disaster damage assessment. User-generated 3D building models from Google Building Maker are compared with LiDAR-derived building models using 3D shape signatures. Eighteen 3D building models are created in Fremont, California using the Google Building Maker, and six shape functions (distance, angle, area, volume, slope, and aspect) are applied to the 18 LiDAR-derived building models and user-generated ones. A special case regarding the comparison between LiDAR data and building models with indented walls is also discussed. Based on the results, several conclusions are drawn, and limitations that require further study are also discussed.
4

Modelling and analysing 3D building interiors with the dual half-edge data structure

Boguslawski, Pawel January 2011 (has links)
While many systems and standards like CAD systems or CityGML permit the user to represent the geometry and the semantics of building interior models, their use for applications where spatial analysis and/or real-time modifications are required are limited since they lack the possibility to store topological relationships between the elements. In this thesis a new topological data structure, the dual half-edge (DHE) is presented. It permits the representation of the topology of building models with the interior included. It is based on the idea of simultaneously storing a graph in 3D space and its dual graph, and to link the two. Euler-type operators for incrementally constructing 3D models (for adding individual edges, faces and volumes to the model while updating the dual structure simultaneously), and navigation operators (for example to navigate from a given point to all the connected planes or polyhedra) are proposed. The DHE also permits the assigning of attributes to any element. This technique allows the handling of important query types and performs analysis based on the building structure, for example finding the nearest exterior exit to a given room, as in disaster management planning. As the structure is locally modifiable the model may be adapted whenever a particular pathway is no longer available. The proposed DHE structure adds significant analytic value to the increasingly popular CityGML model, and to the CAD field where the dual structure is of growing interest.
5

Systém pro tvorbu 3D modelů budov z půdorysů / System for Modelling of 3D Buildings from Floor Plans

Jurka, Zdeněk January 2012 (has links)
This work deals with description and design of application for generating 3D building models from floor plans and their publication on the Internet. First chapter describes methods used for floor plans creation. Next part describes how are foor plans transformed into three-dimensional model. Following chapters describes implementation details concerning application used for creation of building floor plan and three-dimensional model generation. Work also covers implementation of web based application for viewing models in web browser. Final chapters sums up results and limitations of described solution. There are also discussed possible extensions of current project.
6

Dynamic building model integration

Viljoen, Dewald 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The amount and complexity of software applications for the building industry is increasing constantly. It has been a long term goal of the software industry to support integration of the various models and applications. This is a difficult task due to the complexity of the models and the diversity of the fields that they model. As a result, only large software houses have the ability to provide integrated solutions on the basis of a common information model. Such a model can more easily be established since the different software is developed within the same group. Other software suppliers usually have to revert to importing and exporting of data to establish some form of integration. Even large software houses still sometimes make use of this technique between their different packages. In order to obtain a fully integrated solution, clients have to acquire complex and expensive software, even if only a small percentage of the functionality of this software is actually required. A different approach to integration is proposed here, based on providing an integration framework that links different existing software models. The framework must be customisable for each individual's unique requirements as well as for the software already used by the individual. In order for the framework to be customisable, it must either encompass the information requirements of all existing software models from the outset, or be flexible and adaptable for each user. Developing an encompassing software model is difficult and expensive and thus the latter approach is followed here. The result is a model that is less general than BIM-style models, but more focussed and less complex. The elements of this flexible model do not have predetermined properties, but properties can instead be added and removed at runtime. Furthermore, derived properties are not stored as values, but rather as methods by which their values are obtained. These can also be added, removed and modified at runtime. These two concepts allow the structure and the functionality of the model to be changed at runtime. An added advantage is that a knowledgeable user can do this himself. Changes to the models can easily be incorporated in the integration framework, so their future development is not limited. This has the advantage that the information content of the various applications does not have to be pre-determined. It is acknowledged that a specific solution is required for each integration model; however the user still has full control to expand his model to the complexity of BIM-type models. Furthermore, if new software models are developed to incorporate the proposed structures, even more seamless and flexible integration will be possible. The proposed framework is demonstrated by linking a CAD application to a cost-estimation application for buildings. A prototype implementation demonstrates full integration by synchronising selection between the different applications. / AFRIKAANSE OPSOMMING: Die hoeveelheid en kompleksiteit van sagteware programme vir die bou industrie is konstant aan die vermeerder. Dit was nog altyd 'n lang termyn doelwit van die sagteware industrie om integrasie van die verskeie modelle en programme te ondersteun. Hierdie is 'n moeilike taak as gevolg van die kompleksiteit van die modelle, en die diversiteit van die velde wat hierdie programme modelleer. Die gevolg is dat net groot sagteware huise die vermoë het om geïntegreerde oplossings te bied op die basis van 'n gemeenskaplike inligting model. So 'n tipe model kan makliker bymekaargestel word siende dat al die verskillende sagteware binne dieselfde groep ontwikkel word. Ander sagteware verskaffers moet gewoonlik gebruik maak van sogenaamde uitvoer/invoer tegnieke om 'n mate van integrasie te verkry. Selfs groot sagteware huise maak ook gebruik van hierdie tegnieke tussen hulle verskeie pakkette, in plaas van om die programme direk met mekaar te koppel. Om 'n vol geïntegreerde oplossing te verkry, moet kliënte komplekse en duur sagteware aanskaf, selfs al word net 'n klein gedeelte van die funksionaliteit van hierdie sagteware gebruik. 'n Verskillende benadering word hier gevolg, gebaseer op 'n integrasie raamwerk wat verskillende bestaande sagteware modelle met mekaar koppel. Die raamwerk moet aanpasbaar wees vir elke individu se unieke opset. Vir die raamwerk om aanpasbaar te wees, moet dit óf alle bou industrie inligting inkorporeer van die staanspoor af, óf dit moet buigbaar en aanpasbaar wees vir elke gebruiker. Om 'n model te ontwikkel wat alle bestaande inligting inkorporeer van die staanspoor af is moeilik en duur, dus word die tweede benadering gevolg. Die eindresultaat is 'n model wat minder omvattend is as BIM-tipe modelle, maar eerder gefokus en minder kompleks. Die elemente van hierdie buigbare model het nie voorafbepaalde eienskappe nie, eienskappe kan bygevoeg en weggevat word terwyl die program hardloop. Verder word afgeleide eienskappe nie gestoor as waardes nie, maar eerder as metodes wat gebruik word om hulle waardes mee af te lei. Hierdie konsepte laat toe dat die struktuur en funksionaliteit van die model verander kan word terwyl die program hardloop. 'n Verdere voordeel is dat 'n kundige verbruiker die veranderinge self kan doen. Veranderinge in die modelle kan maklik ingesluit word in die integrasie model, so toekomstige ontwikkeling word nie beperk nie. Dit beteken dat die inhoud van die modelle nie vooraf bepaal hoef te word nie. Al het die raamwerk 'n gespesialiseerde oplossing vir elke gebruiker tot gevolg, het die gebruiker nogtans volle beheer om sy model uit te brei tot die omvattendheid van BIM-tipe modelle. Indien nuwe sagteware modelle ontwikkel word met die integrasie raamwerk in gedagte, kan nog gladder en buigbare integrasie moontlik wees. In hierdie tesis word 'n tekenprogram met 'n kosteberaming program gekoppel om die voorgestelde raamwerk te demonstreer. 'n Prototipe implementering demonstreer volle integrasie deur seleksie binne die programme te sinchroniseer.
7

Implementing augmented reality for visualisation of virtual buildings using Android / Implementing augmented reality for visualisation of virtual buildings using Android

Dąbrowski, Piotr Władysław January 2011 (has links)
The mobile phone devices are still developing and they are gaining more functionality and are able to deal with more advanced tasks. One of the technologies timidly trying to approach the mobile phone market is the augmented reality, which does no longer require external equipment to be formed in a programming application. There is a limited number of sources trying to describe the accuracy of augmented reality applications implemented on mobile devices. Within this study an application of augmented reality visualising virtual models of buildings was implemented on a mobile phone device in order to evaluate the rate of the device explication. Several tests were conducted to evaluate the application total accuracy. The implemented application was visualising virtual models of the real existing buildings displaying them in the same place the original buildings were. The final position was calculated by the application and the discrepancy of the view between the model and the real building was measured. The results were gathered revealing the application’s real accuracy. For the purposes of this study the functional application of augmented reality has been created. The application was implemented on the mobile phone. The results of the application formed the tables with final measurements of accuracy. Also several photographs were taken from the areas of the real existing buildings. Transferring the functionality of augmented reality from the external devices to mobile phones is possible with some harm to the application accuracy. Visualising building models is one of the possible extensions of the mobile phone market. The improvements in Global Positioning System would significantly improve the application´s general accuracy. / The augmented reality represents one of the most current approach in implementing the artificial reality. Primarily required large extensive head-mounted-displays now follows the trend of minimising the necessary equipment. The study shows how is it done that a single mobile phone can be used as a device creating a new reality and also answers what calculations are required by such a system setting the augmented environment. Also a problem of mobile phone’s augmented reality systems accuracy is developed in reference to the commonly proclaimed 2-metres inaccuracy of the GPS device. / (+48) 506 403 407 (PL)
8

Segmentation of facade images with shape priors / Segmentation des images de façade avec à priori sur la forme

Kozinski, Mateusz 30 June 2015 (has links)
L'objectif de cette thèse concerne l'analyse automatique d'images de façades de bâtiments à partir de descriptions formelles à priori de formes géométriques. Ces informations suggérées par un utilisateur permettent de modéliser, de manière formelle, des contraintes spatiales plus ou moins dures quant à la segmentation sémantique produite par le système. Ceci permet de se défaire de deux principaux écueils inhérents aux méthodes d'analyse de façades existantes qui concernent d'une part la coûteuse fidélité de la segmentation résultante aux données visuelles de départ, d'autre part, la spécificité architecturale des règles imposées lors du processus de traitement. Nous proposons d'explorer au travers de cette thèse, différentes méthodes alternatives à celles proposées dans la littérature en exploitant un formalisme de représentation d'à priori de haut niveau d'abstraction, les propriétés engendrées par ces nouvelles méthodes ainsi que les outils de résolution mis en œuvres par celles-ci. Le système résultant est évalué tant quantitativement que qualitativement sur de multiples bases de données standards et par le biais d'études comparatives à des approches à l'état de l'art en la matière. Parmi nos contributions, nous pouvons citer la combinaison du formalisme des grammaires de graphes exprimant les variations architecturales de façades de bâtiments et les modèles graphiques probabilistes modélisant l'énergie attribuée à une configuration paramétrique donnée, dans un schéma d'optimisation par minimisation d'énergie; ainsi qu'une nouvelle approche par programmation linéaire d'analyse avec à priori de formes. Enfin, nous proposons un formalisme flexible de ces à priori devançant de par ses performances les méthodes à l'état de l'art tout en combinant les avantages de la généricité de contraintes simples manuellement imposées par un utilisateur, à celles de la précision de la segmentation finale qui se faisait jusqu'alors au prix d'un encodage préliminaire restrictif de règles grammaticales complexes propres à une famille architecturale donnée. Le système décrit permet également de traiter avec robustesse des scènes comprenant des objets occultants et pourrait encore être étendu notamment afin de traiter l'extension tri-dimensionnelle de la sémantisation d'environnements urbains sous forme de nuages de points 3D ou d'une analyse multi-image de bâtiments / The aim of this work is to propose a framework for facade segmentation with user-defined shape priors. In such a framework, the user specifies a shape prior using a rigorously defined shape prior formalism. The prior expresses a number of hard constraints and soft preference on spatial configuration of segments, constituting the final segmentation. Existing approaches to the problem are affected by a compromise between the type of constraints, the satisfaction of which can be guaranteed by the segmentation algorithm, and the capability to approximate optimal segmentations consistent with a prior. In this thesis we explore a number of approaches to facade parsing that combine prior formalism featuring high expressive power, guarantees of conformance of the resulting segmentations to the prior, and effective inference. We evaluate the proposed algorithms on a number of datasets. Since one of our focus points is the accuracy gain resulting from more effective inference algorithms, we perform a fair comparison to existing methods, using the same data term. Our contributions include a combination of graph grammars for expressing variation of facade structure with graphical models encoding the energy of models of given structures for different positions of facade elements. We also present the first linear formulation of facade parsing with shape priors. Finally, we propose a shape prior formalism that enables formulating the problem of optimal segmentation as the inference in a Markov random field over the standard four-connected grid of pixels. The last method advances the state of the art by combining the flexibility of a user-defined grammar with segmentation accuracy that was reserved for frameworks with pre-defined priors before. It also enables handling occlusions by simultaneously recovering the structure of the occluded facade and segmenting the occluding objects. We believe that it can be extended in many directions, including semantizing three-dimensional point clouds and parsing images of general urban scenes
9

Multi-scale representations of virtual 3D city models

Glander, Tassilo January 2012 (has links)
Virtual 3D city and landscape models are the main subject investigated in this thesis. They digitally represent urban space and have many applications in different domains, e.g., simulation, cadastral management, and city planning. Visualization is an elementary component of these applications. Photo-realistic visualization with an increasingly high degree of detail leads to fundamental problems for comprehensible visualization. A large number of highly detailed and textured objects within a virtual 3D city model may create visual noise and overload the users with information. Objects are subject to perspective foreshortening and may be occluded or not displayed in a meaningful way, as they are too small. In this thesis we present abstraction techniques that automatically process virtual 3D city and landscape models to derive abstracted representations. These have a reduced degree of detail, while essential characteristics are preserved. After introducing definitions for model, scale, and multi-scale representations, we discuss the fundamentals of map generalization as well as techniques for 3D generalization. The first presented technique is a cell-based generalization of virtual 3D city models. It creates abstract representations that have a highly reduced level of detail while maintaining essential structures, e.g., the infrastructure network, landmark buildings, and free spaces. The technique automatically partitions the input virtual 3D city model into cells based on the infrastructure network. The single building models contained in each cell are aggregated to abstracted cell blocks. Using weighted infrastructure elements, cell blocks can be computed on different hierarchical levels, storing the hierarchy relation between the cell blocks. Furthermore, we identify initial landmark buildings within a cell by comparing the properties of individual buildings with the aggregated properties of the cell. For each block, the identified landmark building models are subtracted using Boolean operations and integrated in a photo-realistic way. Finally, for the interactive 3D visualization we discuss the creation of the virtual 3D geometry and their appearance styling through colors, labeling, and transparency. We demonstrate the technique with example data sets. Additionally, we discuss applications of generalization lenses and transitions between abstract representations. The second technique is a real-time-rendering technique for geometric enhancement of landmark objects within a virtual 3D city model. Depending on the virtual camera distance, landmark objects are scaled to ensure their visibility within a specific distance interval while deforming their environment. First, in a preprocessing step a landmark hierarchy is computed, this is then used to derive distance intervals for the interactive rendering. At runtime, using the virtual camera distance, a scaling factor is computed and applied to each landmark. The scaling factor is interpolated smoothly at the interval boundaries using cubic Bézier splines. Non-landmark geometry that is near landmark objects is deformed with respect to a limited number of landmarks. We demonstrate the technique by applying it to a highly detailed virtual 3D city model and a generalized 3D city model. In addition we discuss an adaptation of the technique for non-linear projections and mobile devices. The third technique is a real-time rendering technique to create abstract 3D isocontour visualization of virtual 3D terrain models. The virtual 3D terrain model is visualized as a layered or stepped relief. The technique works without preprocessing and, as it is implemented using programmable graphics hardware, can be integrated with minimal changes into common terrain rendering techniques. Consequently, the computation is done in the rendering pipeline for each vertex, primitive, i.e., triangle, and fragment. For each vertex, the height is quantized to the nearest isovalue. For each triangle, the vertex configuration with respect to their isovalues is determined first. Using the configuration, the triangle is then subdivided. The subdivision forms a partial step geometry aligned with the triangle. For each fragment, the surface appearance is determined, e.g., depending on the surface texture, shading, and height-color-mapping. Flexible usage of the technique is demonstrated with applications from focus+context visualization, out-of-core terrain rendering, and information visualization. This thesis presents components for the creation of abstract representations of virtual 3D city and landscape models. Re-using visual language from cartography, the techniques enable users to build on their experience with maps when interpreting these representations. Simultaneously, characteristics of 3D geovirtual environments are taken into account by addressing and discussing, e.g., continuous scale, interaction, and perspective. / Gegenstand der Arbeit sind virtuelle 3D-Stadt- und Landschaftsmodelle, die den städtischen Raum in digitalen Repräsentationen abbilden. Sie werden in vielfältigen Anwendungen und zu unterschiedlichen Zwecken eingesetzt. Dabei ist die Visualisierung ein elementarer Bestandteil dieser Anwendungen. Durch realitätsnahe Darstellung und hohen Detailgrad entstehen jedoch zunehmend fundamentale Probleme für eine verständliche Visualisierung. So führt beispielsweise die hohe Anzahl von detailliert ausmodellierten und texturierten Objekten eines virtuellen 3D-Stadtmodells zu Informationsüberflutung beim Betrachter. In dieser Arbeit werden Abstraktionsverfahren vorgestellt, die diese Probleme behandeln. Ziel der Verfahren ist die automatische Transformation virtueller 3D-Stadt- und Landschaftsmodelle in abstrakte Repräsentationen, die bei reduziertem Detailgrad wichtige Charakteristika erhalten. Nach der Einführung von Grundbegriffen zu Modell, Maßstab und Mehrfachrepräsentationen werden theoretische Grundlagen zur Generalisierung von Karten sowie Verfahren zur 3D-Generalisierung betrachtet. Das erste vorgestellte Verfahren beschreibt die zellbasierte Generalisierung von virtuellen 3DStadtmodellen. Es erzeugt abstrakte Repräsentationen, die drastisch im Detailgrad reduziert sind, erhält dabei jedoch die wichtigsten Strukturen, z.B. das Infrastrukturnetz, Landmarkengebäude und Freiflächen. Dazu wird in einem vollautomatischen Verfahren das Eingabestadtmodell mithilfe des Infrastrukturnetzes in Zellen zerlegt. Pro Zelle wird abstrakte Gebäudegeometrie erzeugt, indem die enthaltenen Einzelgebäude mit ihren Eigenschaften aggregiert werden. Durch Berücksichtigung gewichteter Elemente des Infrastrukturnetzes können Zellblöcke auf verschiedenen Hierarchieebenen berechnet werden. Weiterhin werden Landmarken gesondert berücksichtigt: Anhand statistischer Abweichungen der Eigenschaften der Einzelgebäudes von den aggregierten Eigenschaften der Zelle werden Gebäude gegebenenfalls als initiale Landmarken identifiziert. Schließlich werden die Landmarkengebäude aus den generalisierten Blöcken mit Booleschen Operationen ausgeschnitten und realitätsnah dargestellt. Die Ergebnisse des Verfahrens lassen sich in interaktiver 3D-Darstellung einsetzen. Das Verfahren wird beispielhaft an verschiedenen Datensätzen demonstriert und bezüglich der Erweiterbarkeit diskutiert. Das zweite vorgestellte Verfahren ist ein Echtzeit-Rendering-Verfahren für geometrische Hervorhebung von Landmarken innerhalb eines virtuellen 3D-Stadtmodells: Landmarkenmodelle werden abhängig von der virtuellen Kameradistanz vergrößert, so dass sie innerhalb eines spezifischen Entfernungsintervalls sichtbar bleiben; dabei wird ihre Umgebung deformiert. In einem Vorverarbeitungsschritt wird eine Landmarkenhierarchie bestimmt, aus der die Entfernungsintervalle für die interaktive Darstellung abgeleitet werden. Zur Laufzeit wird anhand der virtuellen Kameraentfernung je Landmarke ein dynamischer Skalierungsfaktor bestimmt, der das Landmarkenmodell auf eine sichtbare Größe skaliert. Dabei wird der Skalierungsfaktor an den Intervallgrenzen durch kubisch interpoliert. Für Nicht-Landmarkengeometrie in der Umgebung wird die Deformation bezüglich einer begrenzten Menge von Landmarken berechnet. Die Eignung des Verfahrens wird beispielhaft anhand verschiedener Datensätze demonstriert und bezüglich der Erweiterbarkeit diskutiert. Das dritte vorgestellte Verfahren ist ein Echtzeit-Rendering-Verfahren, das eine abstrakte 3D-Isokonturen-Darstellung von virtuellen 3D-Geländemodellen erzeugt. Für das Geländemodell wird eine Stufenreliefdarstellung für eine Menge von nutzergewählten Höhenwerten erzeugt. Das Verfahren arbeitet ohne Vorverarbeitung auf Basis programmierbarer Grafikkarten-Hardware. Entsprechend erfolgt die Verarbeitung in der Prozesskette pro Geometrieknoten, pro Dreieck, und pro Bildfragment. Pro Geometrieknoten wird zunächst die Höhe auf den nächstliegenden Isowert quantisiert. Pro Dreieck wird dann die Konfiguration bezüglich der Isowerte der drei Geometrieknoten bestimmt. Anhand der Konfiguration wird eine geometrische Unterteilung vorgenommen, so dass ein Stufenausschnitt entsteht, der dem aktuellen Dreieck entspricht. Pro Bildfragment wird schließlich die finale Erscheinung definiert, z.B. anhand von Oberflächentextur, durch Schattierung und Höheneinfärbung. Die vielfältigen Einsatzmöglichkeiten werden mit verschiedenen Anwendungen demonstriert. Die Arbeit stellt Bausteine für die Erzeugung abstrakter Darstellungen von virtuellen 3D-Stadt und Landschaftsmodellen vor. Durch die Orientierung an kartographischer Bildsprache können die Nutzer auf bestehende Erfahrungen bei der Interpretation zurückgreifen. Dabei werden die charakteristischen Eigenschaften 3D geovirtueller Umgebungen berücksichtigt, indem z.B. kontinuierlicher Maßstab, Interaktion und Perspektive behandelt und diskutiert werden.
10

Static and Dynamic Behavior of Reinforced Masonry : Experimental and Analytical Investigations

Anant, Joshi Amrut January 2015 (has links) (PDF)
The most common form of dwellings in rural and semi-urban areas of India and other developing countries around the globe are one/two storey unreinforced masonry (URM) buildings. It is well known that such masonry buildings are most vulnerable during earthquakes. Out-of-plane flexural failures of walls are primarily responsible for collapse of URM buildings during an earthquake. The seismic performance of such buildings can be improved by reinforcing masonry walls in the horizontal and vertical directions with materials like steel, bamboo or fiber reinforced polymers (FRP). It is fairly easy to reinforce masonry in the horizontal direction by embedding the reinforcement in the bed joints of masonry construction. However, in the vertical direction, the reinforcement is generally provided in the cavities of hollow masonry units, which are grouted after placing the reinforcement. Even though the in-plane performance of masonry walls is enhanced with such a reinforcing technique, it still falls short in resisting out-of-plane lateral loads, as the vertical reinforcement is located close to neutral axis of bending. Hence, a novel technique of reinforcing masonry in the vertical direction on both the faces of the wall called containment reinforcement is proposed recently. Containment reinforcement improves ductility, energy dissipation and prevents overturning failure due to out-of-plane loading. The present study examines the role of containment reinforcement in improving out-of-plane / in-plane behavior of masonry. The research program consisted of characterizing the physical properties of the constituent materials of reinforced masonry, namely stabilized earth blocks, cement-soil-sand (1:1:6) mortar and steel and FRP reinforcement. The strength and elastic properties of masonry assemblages under compression, flexure and shear have been determined. The flexural behavior of three types of reinforced masonry assemblages namely; stretcher bond, English bond and rat-trap bond masonry beams under monotonic and reversed cyclic loading test protocols have been examined. The beams were reinforced with steel, Glass FRP (GFRP) and Carbon FRP (CFRP) materials. In the monotonic test protocol the moment-curvature relationships and ductility for each type of masonry beams were obtained. In the cyclic test protocols, the hysteretic behavior, energy dissipation and equivalent viscous damping characteristics were obtained. The shear behavior of unreinforced and reinforced masonry panels under diagonal tension (shear) was examined through monotonic and cyclic loading test protocols. A simple and cost effective device for producing horizontal to and fro motion to imitate earthquake ground motions, called shock table test facility, has been designed. The table platform is mounted on four wheels and moves on rails. The table is put into the motion through pendulum impacts. The table motion characteristics have been obtained using the parameters used to describe the earthquake ground motions like amplitude, frequency content, duration of the motion and mixed parameters. The parameters of the shock table motion have been compared with few of the recorded earthquake ground motions to evaluate the effectiveness of shock table testing protocol for examining the dynamic performance of scaled masonry building models. The performance of two half scaled containment reinforced masonry building models subjected to base motions provided through shock table and conventional shaking table was evaluated. The dynamic properties of masonry, responses and failure patterns were obtained. A non-linear finite element (FE) model was developed and calibrated using the experimental data generated in the flexural and shear testing of reinforced and unreinforced masonry beams and panels. The FE model was further used for analysis of half scale masonry building model tested on shock table and recalibrated by comparing responses of numerical model with experimentally measured responses. Furthermore, the finite element model was used to assess the performance of two storey unreinforced and containment reinforced symmetric/asymmetric masonry buildings subjected to a series of earthquake ground motions of increasing severity. The studies conducted conclude that the masonry with containment reinforcement was effective in mitigating seismic risks of masonry buildings in moderate to severe seismic regions. The provision of containment reinforcement significantly improved equivalent hysteretic damping at design displacement and offered excellent ductility to masonry elements. The existing construction practice can easily accommodate the provision of containment reinforcement with little modification to the construction sequence. The extra effort in construction does commensurate with the enhancement in the seismic performance of the masonry buildings.

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