A PERSPECTIVE ON PROCEDURAL MODELING BASED ON STRUCTURAL ANALYSIS

[EN] We introduce a study focused on procedural modeling papers that use methods of structural analysis, especially in its application to historic buildings such as churches and cathedrals. Moreover, we have taken a geometric structure of one of these papers and studied their behavior in a generic simulation tool, thus showing the feasibility of its analysis with non-specialized tools.[ES] Introducimos un estudio centrado en aquellos trabajos de modelado procedural que utilizan métodos de análisis estructural, especialmente en su aplicación para edificios históricos como iglesias y catedrales. Por otra parte, hemos tomado una estructura geométrica de uno de estos artículos y estudiado su comportamiento en una herramienta de simulación genérica, mostrando su factibilidad para realizar análisis con herramientas no especializadas.Fita, JL.; Besuievsky, G.; Patow, GA. (2016). A PERSPECTIVE ON PROCEDURAL MODELING BASED ON STRUCTURAL ANALYSIS. En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 264-266. https://doi.org/10.4995/arqueologica8.2015.304526426

Design of structurally-sound masonry buildings using 3D static analysis

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (p. 95-100).In the design of buildings, structural analysis is traditionally performed after the aesthetic design has been determined and has little in uence on the overall form. This thesis presents methods to integrate architectural design and structural analysis. While existing tools focus on providing an analysis of the stress state, the proposed methods focus on geometry and equilibrium to obtain forms that are more structurally sound. The feasibility of masonry structures is modeled using a novel penalty formulation, assuming a rigid-block behavior of masonry. Two methods were developed that apply this model of feasibility to structural optimization. In the first approach, structural feasibility is introduced into procedural modeling of buildings. A set of designated free parameters are automatically tuned to achieve structural feasibility constraints. It is demonstrated how this allows for more realistic structural models that can be interacted with in physical simulations. In the second approach, a closed form derivation of structural gradients is presented that measures the change in stability of a building with respect to geometry modifications. The method computes the gradient of structural feasibility constraints, parameterized by vertex modifications. The gradients are visualized as interaction tools, giving user-guidance for effectively modifying a structural design. User-controlled constraints, formulated as penalty functions, are incorporated so that the user can explore variations of structurally feasible designs.by Emily Jing Wei Whiting.Ph.D

Structural optimization of 3D masonry buildings

In the design of buildings, structural analysis is traditionally performed after the aesthetic design has been determined and has little influence on the overall form. In contrast, this paper presents an approach to guide the form towards a shape that is more structurally sound. Our work is centered on the study of how variations of the geometry might improve structural stability. We define a new measure of structural soundness for masonry buildings as well as cables, and derive its closed-form derivative with respect to the displacement of all the vertices describing the geometry. We start with a gradient descent tool which displaces each vertex along the gradient. We then introduce displacement operators, imposing constraints such as the preservation of orientation or thickness; or setting additional objectives such as volume minimization.Shell Oil CompanyNatural Sciences and Engineering Research Council of Canada (PGS Program)Samsung Scholarship Foundatio

Una perspectiva sobre el modelado procedural basado en análisis estructurales

[EN] With the rise of available computing capabilities, structural analysis has recently become a key tool for building assessment usually managed by art historians, curators, and other specialist related to the study and preservation of ancient buildings. On the other hand, the flourishing field of procedural modeling has provided some exciting breakthroughs for the recreation of lost buildings and urban structures. However, there is a surprising lack of literature to enable the production of procedural-based buildings taking into account structural analysis, which has proven to be a crucial element for the recreation of faithful masonry structures. In order to perform an in-depth study of the advances in this type of analysis for cultural heritage buildings, we performed a study focused on procedural modeling that make use of structural analysis methods, especially in its application to historic masonry buildings such as churches and cathedrals. Moreover, with the aim of improving the knowledge about structural analysis of procedurally-recreated historical buildings, we have taken a geometric structure, added a set of procedural walls structured in masonry bricks, and studied its behavior in a generic, freely-available simulation tool, thus showing the feasibility of its analysis with non-specialized tools. This not only has allowed us to understand and learn how the different parameter values of a masonry structure can affect the results of the simulation, but also has proven that this kind of simulations can be easily integrated in an off-the-shelf procedural modeling tool, enabling this kind of analysis for a wide variety of historical studies, or restoration and preservation actions.[ES] Con el creciente aumento de las capacidades computacionales, el análisis estructural se ha convertido en una herramienta clave para la evaluación del estudio y conservación de edificios antiguos por parte de los historiadores del arte, curadores y otros especialistas. Por otro lado, el floreciente campo del modelado procedural ha proporcionado avances interesantes para la reconstrucción de edificios y estructuras urbanas no accesibles. Sin embargo, hay una sorprendente falta de métodos que permiten la generación deedificios procedurales, teniendo en cuenta el análisis estructural, los cuales handemostrado ser un elemento crucial para la concepciónde estructuras de mampostería. Con el fin de realizar un estudio en profundidad de los avances en este tipo de análisis para edificios del patrimonio cultural, se realizó un estudio centrado en elroldelmodelado proceduralque realizanmétodos de análisis estructural, especialmente en su aplicación a los edificios históricos de albañilería, tales como iglesias y catedrales. Por otra parte, con el objetivo de mejorar el conocimiento sobre el análisis estructural de los edificios históricos concebidosproceduralmente, hemos tomado una estructura geométrica de un atrículo, añadidoun conjunto de paredesproceduralesestructuradasen ladrillos, y estudiado su comportamiento conuna herramienta de simulación de pública disponibilidad.Con esto sedemuestra la viabilidad de su análisis con herramientas no especializadas. Esto no sólo nos ha permitido entender y aprender cómo los diferentes valores de los parámetros de una estructura de mampostería pueden afectar los resultados de la simulación, sino tambiénque este tipo de simulaciones se puede integrar fácilmente en una herramienta de modelado proceduralal alcance de todo público, lo que permite acercar este tipo de análisis a una amplia variedad de estudios históricos o acciones de restauración y conservación.This work was partially funded by the TIN2014-52211-C2-2-R project from Ministerio de Economia y Competividad, Spain.Fita, JL.; Besuievsky, G.; Patow, G. (2017). A perspective on procedural modeling based on structural analysis. Virtual Archaeology Review. 8(16):44-50. https://doi.org/10.4995/var.2017.5765SWORD445081

Recreation of architectural structures using procedural modeling based on volumes

[ES] Si bien el modelado procedural de edificios y otras estructuras arquitectónicas ha evolucionado de manera muy significativa en los últimos años, existe una notable ausencia de herramientas de alto nivel que permitan a un diseñador, un artista o un historiador, crear edificios o estructuras arquitectónicasimportantes de alguna ciudad en particular. En este trabajo presentaremos una herramienta para la creación de este tipo de edificios de manera simple y clara, siguiendo reglas que utilicen el lenguaje y metodología de creación propios de los edificios, y ocultando al usuario los detalles algorítmicos de lacreación del modelo.[EN] While the procedural modeling of buildings and other architectural structures has evolved very significantly in recent years, there is noticeable absence of high-level tools that allow a designer, an artist or an historian, creating important buildings or architectonic structures in a particular city. In this paper we present a tool for creating buildings in a simple and clear, following rules that use the language and methodology of creating their own buildings, and hiding the user the algorithmic details of the creation of the model.Queremos agradecer a Emily Whiting por los ejemplos que nos facilitó, así como a todos los miembros del Grup de Geometriai Gràfics de la Universitat de Girona por toda su ayuda. Este proyecto fue parcialmente financiado con el proyecto TIN2010-20590-C02-02 del Ministerio de Ciencia e Innovación.Barroso Juan, S.; Patow, G. (2013). Recreación de estructuras arquitectónicas mediante modelaje procedural basado en volúmenes. Virtual Archaeology Review. 4(9):76-81. https://doi.org/10.4995/var.2013.4251OJS768149P. Wonka, M. Wimmer, F. Sillion, and W. Ribarsky. Instant architecture. ACM Transaction on Graphics, 22(3):669-677, July 2003. Proceedings ACM SIGGRAPH 2003. 10. http://dx.doi.org/10.1145/1201775.882324P. Müller, P. Wonka, S. Haegler A. Ulmer, and L. Van Gool. Procedural modeling of buildings. ACM Trans. Graph., 25 (3):614-623, 2006. http://dx.doi.org/10.1145/1141911.1141931G. Patow, User-Friendly Graph Editing for Procedural Buildings. IEEE Computer Graphics and Applications, vol. 32, no. 2, Mar./Apr. 2012, pp. 66-75; doi:10.1109/MCG.2010.104. http://dx.doi.org/10.1109/MCG.2010.104E. Whiting, J. Ochendorf, F. Durand, Procedural modeling of structurally-sound masonry buildings. ACMSIGGRAPH Asia 2009 papers (New York, NY, USA, 2009), SIGGRAPH Asia '09, ACM, pp. 112:1-112

Restauraciones antiguas: enfoque estructural numérico para la identificación y reinterpretación de la secuencia constructiva del Medracen

[EN] This paper addresses the importance of a structural approach for identifying and interpreting building chronology, as well as for the establishment of historical stratigraphy. Through structural analyses, carried out on the oldest extant royal mausoleum in North Africa, the Medracen (4th-3rd century BC), located in eastern Algeria, it has been possible to identify building sequences and structural characteristics; a reinterpretation of its constructive sequence within a specific historical context was also suggested. A static linear Finite Element Method (FEM) analysis was performed on a simplified 3D model conceived with solid elements to assess the structural behaviour of the structure under the effect of its self-weight and to identify, consequently, its construction sequence. The equilibrium approach was effective in identifying the structure s geometry. Results show that Medracen s ancient restoration was a strengthening intervention strategy and had a symbolic aim related to the function of the funerary building. Restoration works, consisting of repairing specific parts of the building and adding an external cladding, as a whole architectural entity, contributed to reducing the effect of tensile stress, therefore, stabilizing the inner core. Besides, this same action was a means for the Numidian elite to transform an ancient monumental burial (sepulchrum) into a monument (monumentum) with cultural significance likely to convey socio-political messages relating to power and sovereignty. Therefore, we can speak of an evolutionary restoration that reflects the ambitions of the Numidian elite to become part of the Mediterranean orbit.[ES] Este artículo aborda la importancia del análisis estructural para la identificación e interpretación de la cronología de la construcción y el establecimiento de una estratigrafía histórica. A través de un análisis estructural, realizado sobre el mausoleo real más antiguo que se conserva en Argelia en el norte de África, el Medracen (siglos IV-III a.C.) localizado en su parte oriental, se han podido identificar algunas secuencias constructivas y características estructurales con el objetivo de sugerir una reinterpretación de su cronología constructiva enmarcada en un contexto histórico específico. Se realizó un análisis estático lineal por elementos finitos sobre un modelo 3D simplificado, concebido con elementos sólidos, para evaluar el comportamiento estructural del monumento bajo el efecto de su peso propio e identificar, en consecuencia, su secuencia constructiva. Por otro lado, el enfoque del equilibrio del conjunto fue eficaz para identificar la geometría de la estructura. Los resultados muestran que la antigua restauración de Medracen tuvo como meta una intervención de refuerzo y un objetivo simbólico relacionado con la función del edificio funerario. La restauración, consistente en la reparación de partes específicas del edificio y la adición de un paramento exterior, como entidad arquitectónica de pleno derecho, contribuyó a reducir el efecto de las tensiones de tracción, estabilizando así el núcleo interno. Además, esta misma acción fue un medio para que la élite Númida transformase un antiguo sepulcro (sepulchrum) en un monumento (monumentum) con significado cultural capaz de transmitir mensajes sociopolíticos relacionados con el poder y la soberanía. Por lo tanto, se puede hablar de una "restauración evolutiva" que refleja las ambiciones de la élite númida de integrarse en la órbita mediterránea.Amokrane, L.; Kassab, T.; Monjo-Carrio, J. (2022). Ancient restorations: computer-based structural approach for the identification and reinterpretation of the Medracen's constructive sequence. Virtual Archaeology Review. 13(27):33-48. https://doi.org/10.4995/var.2022.17394OJS3348132

Designer-driven 3D buildings generated using variable neighborhood search

This paper presents a mechanism to generate virtual buildings considering designer constraints and guidelines. This mechanism is implemented as a pipeline of different Variable Neighborhood Search (VNS) optimization processes in which several subproblems are tackled (1) rooms locations, (2) connectivity graph, and (3) element placement. The core VNS algorithm includes some variants to improve its performance, such as, for example constraint handling and biased operator selection. The optimization process uses a toolkit of construction primitives implemented as "smart objects" providing basic elements such as rooms, doors, staircases and other connectors. The paper also shows experimental results of the application of different designer constraints to a wide range of buildings from small houses to a large castle with several underground levels

Volumetric Procedural Models for Shape Representation

This article describes a volumetric approach for procedural shape modeling and a new Procedural Shape Modeling Language (PSML) that facilitates the specification of these models. PSML provides programmers the ability to describe shapes in terms of their 3D elements where each element may be a semantic group of 3D objects, e.g., a brick wall, or an indivisible object, e.g., an individual brick. Modeling shapes in this manner facilitates the creation of models that more closely approximate the organization and structure of their real-world counterparts. As such, users may query these models for volumetric information such as the number, position, orientation and volume of 3D elements which cannot be provided using surface based model-building techniques. PSML also provides a number of new language-specific capabilities that allow for a rich variety of context-sensitive behaviors and post-processing functions. These capabilities include an object-oriented approach for model design, methods for querying the model for component-based information and the ability to access model elements and components to perform Boolean operations on the model parts. PSML is open-source and includes freely available tutorial videos, demonstration code and an integrated development environment to support writing PSML programs