56.03 Methoden im Bauingenieurwesen
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Der Funktionsumfang von 3D-Modellierern und die Leistung allgemein zur Verfügung stehender Rechnersysteme gestatten die Modellierung beliebiger Objekte in jeder nur denkbaren Fachdisziplin. Das potentielle Leistungsvermögen von 3D-Modellierern sollte Anreiz sein, sie so alltäglich einzusetzen, wie die etablierten Standardapplikationen. Die im Vortrag gezeigten Modelle umfassen ein kleines Spektrum der möglichen Anwendungsgebiete. Weder vom (Daten)Umfang noch von ihrem Kompliziertheitsgrad stellen sie etwas Besonderes dar. Sie sollen nur das Interesse für einen alltäglichen Einsatz von 3D-Modellierern wecken und eventuell vorhandenen Einsatzschwellen abbauen helfen. Die im Vortrag gezeigten Bildfolgen sind unter http://www.uni-weimar.de/animationen zu finden.
Das Eintreffen der Passagiere einer Haltestelle eines öffentlichen Nahverkehrsmittel wird als stochastischer Prozeß beschrieben . Die Ankünfte der Nahverkehrsmittel stellen einen Erneuerungsprozeß dar , wohingegen die Ankünfte der Personen innerhalb einer Erneuerungsperiode als instationärer Poissonprozeß aufgefaßt wird. Über die Intensitätsfunktion liegen Messungen vor. Betrachtet wird die Gesamt- wartezeit der Personen an einer Haltestelle .
Die Entwicklung Berlins zur neuen Hauptstadt des vereinigten Deutschlands erfordert den umfangreichen Ausbau der innerstädtischen Verkehrswege und eine umfassende Einbindung in das bundesweite Verkehrsnetz. Der Ausbau der Inter-City-Express-Strecke zwischen Hannover und Berlin bedingte eine Umplanung großer Streckenabschnitte der Deutschen Bahn AG. Im Zeitalter der computergestützten Informationsverarbeitung sind gerade auf dem Gebiet der Tragwerksplanung konstruktiver Ingenieurbauten vielfältige Möglichkeiten gegeben. So ist bei der Planung von Brückenneubauten eine durchgehende computergestützte Konstruktion und Tragwerksplanung vom Vorentwurf bis hin zur Fertigung möglich. Weiterhin gestatten besondere Berechnungsmethoden bei speziellen Belastungsarten eine exaktere Schnittkraft- und Spannungsermittlung und dadurch eine dem wirklichen Tragverhalten entsprechende genauere Nachweisführung. An Beispielen aus dem konstruktiven Ingenieurbau im Zuge der Sanierung der Berliner Stadtbahn wird die Anwendung moderner Rechentechnik und computergestützter Konstruktionsmethoden und Berechnungsverfahren diskutiert. Die Berliner Stadtbahn wird in weiten Abschnitten über gemauerte Ziegelsteinviadukte geführt. Das Konzept der Sanierungsmaßnahmen sah neben der Anordnung einer lastverteilenden Platte einen Gleisaufbau als Feste Fahrbahn vor. Zusätzlich wurden die Gleisabstände den heutigen Bundesbahnvorschriften angepaßt. Aus diesem Grund wurde eine genaue Nachrechnung der Stadbahnviadukte unter Berücksichtigung der verschiedensten Parameter (z.B. Fugen in der lastverteilenden Platte, Rißbildung im Mauerwerk, Schubverformungen in Fugen zwischen Beton und Mauerwerk bei Überschreitung von Grenzwerten) erforderlich. Die zwischen dem Berliner Hauptbahnhof und dem Bahnhof Jannowitzbrücke befindliche Eisenbahnüberführung über die Holzmarktstraße wurden abgebrochen. Das neue Bauwerk besteht aus einer zweifeldrigen, schiefwinkligen Deckbrücke für 4 Gleise. Auf Grund der komplizierten geometrischen Randbedingungen erfolgte eine durchgängige computergestützte Erstellung der Ausführungsunterlagen. Die Hauptabmessungen der Konstruktion wurden mit Hilfe von Vermessungsdaten bestimmt, die im CAD-Programm verarbeitet wurden. Die CAD-Daten bildeten die geometrischen Eingangsgrößen für das Berechnungsprogramm. Die Querschnittsdimensionierung der Berechnung ging dann in die CAD-Bearbeitung ein. Die Koordinaten für die Werkstattfertigung sowie für die Montage auf der Baustelle ergaben sich ebenfalls aus den Berechnungsergebnissen.
Development of Urban Land Use Model to Compare Transit-Oriented and Automobile-Oriented Cities
(2004)
This study is an attempt to develop a simple simulation model that can compare the differences between automobile-oriented and transit-oriented cities, and clarify the difference between city forms by transportation modes. Following a theoretical model development, a series of simulation runs are tried. The model allocates people who commute to CBD from residential zones along a transportation corridor. As a result of many simulation analyses, it is shown that automobiles need much more traffic space in comparison with the transit as is shown by the proposed traffic space ratio both in CBD and along the corridor.
Digital maps are very easily applied as route guide maps. Route guide maps are provided through Web or a mobile phone services, and demand for such services is increasing. However, the production of a route guide map requires a great deal of time. Therefore, it is difficult for general users to make route guide maps. The purpose of the present research is the development of a system that can generate a route guide map using the Digital Map 2500 (Spatial Data Framework) published by the Geographical Survey Institute. This system will not require advanced equipment or expert knowledge. Therefore, anyone can produce route guide maps easily and quickly. By using the Digital Map 2500, the time and cost required in order to generate a map are reduced. Moreover, a useful route guide map can be created by simplifying the map form based on the human cognitive map.
Change management has been the focus of different IT systems. These IT systems were developed to represent design information, record design rationale, facilitate design coordination and changes. They are largely based on managing reactive changes, particularly design changes, in which changes are recorded and then propagated to the relevant project members. However, proactive changes are hardly dealt with in IT systems. Proactive changes require estimating the likelihood of occurrence of a change event as well as estimating the degree of change impacts on project parameters. Changes in construction projects often result from the uncertainty associated with the imprecise and vague knowledge of much project information at the early stages of projects. This is a major outcome of the case studies carried out as part of this research. Therefore, the proposed model considers that incomplete knowledge and certain project characteristics are always behind change causes. For proactive changes, predicting a change event is the main task for modelling. The prediction model should strive to integrate these main elements: 1) project characteristics that lead to change 2) causes of change, 3) the likelihood of change occurrence, and 4) the change consequences. It should also define the dependency relationships between these elements. However, limited data (documented) are only available from previous projects for change cases and many of the above elements can only be expressed in linguistic terms. This means that the model will simulate the uncertainty and subjectivity associated with these sets of elements. Therefore, a fuzzy model is proposed in this research to capture these elements. The model analyses the impact of each set of elements on the other by assigning fuzzy values for these elements that express the uncertainty and subjectivity of their impact. The main aim is to predict change events and evaluate change effects on project parameters. The fuzzy model described above was developed in an IT system for operational purposes and was designed as a Java package of components with their supporting classes, beans, and files. This paper describes the development and the architecture of the proposed IT system to achieve these requirements. The system is intended to help project teams in dealing with change causes and then the change consequences in construction projects.
Development and Analysis of Sparse Matrix Concepts for Finite Element Approximation on general Cells
(2004)
In engineering and computing, the finite element approximation is one of the most well-known computational solution techniques. It is a great tool to find solutions for mechanic, fluid mechanic and ecological problems. Whoever works with the finite element method will need to solve a large system of linear equations. There are different ways to find a solution. One way is to use a matrix decomposition technique such as LU or QR. The other possibility is to use an iterative solution algorithm like Conjugate Gradients, Gauß-Seidel, Multigrid Methods, etc. This paper will focus on iterative solvers and the needed storage techniques...
For modeling of singular fields of stresses and deformations in elasters with a crack is offered to use of three-dimesional a special finite element. Weak compessible of elasters is taken into account on the basis of threefold approximation of fields of displacements, deformations and function of volume change. At intensive cyclic loading of the elastomer constructions with a crack it is necessary to take into account warming and large deformations at the crack top. The stress-deformed state elasters with a crack is determined from the decision of a nonlinear problem by a modified method Newton-Kantorovich. Account stress intensity factors for a rectangular plate with a various arrangement of a through crack is executed. Process of development of a surface crack and dissipative warming in prismatic a element of shift is investigated.
The paper analyses the application of 3D gaming technologies in the simulation of processes associated with human resources and machinery on construction sites in order to determine process costs. It addresses the problem of detailing in process simulation. The authors outline special boundary conditions for the simulation of cost-relevant resource processes on virtual construction sites. The approach considers different needs for detailing in process simulation during the planning and building phase. For simulation of process costs on a construction site (contractors view) the level of detail has to be set to high. A prototype for determination of process durations (and hereby process costs) developed at the Bauhaus University Weimar is presented as a result of ongoing researches on detailing in process simulation. It shows the method of process cost determination on a high level of detail (game between excavator and truck) through interaction with the virtual environment of the site.
The paper investigates accuracy of deflection predictions made by the finite element package ATENA and design code methods ACI and EC2. Deflections have been calculated for a large number of experimental reinforced concrete beams reported by three investigators. Statistical parameters have been established for each of the technique at different load levels, separately for the beams with small and moderate reinforcement ratio.
Many construction and facilities management Web sites can be found on the Internet. The interested parties on construction and facilities management Web sites can find databases of best practices, calculators, analyzers, software, expert and decision support systems, neural networks, etc. Technological innovation mainly through changes in the availability of information and communication technology inclusive databases of best practices, calculators, analyzers, software, neural networks, decision support and expert systems that have been provided by a variety of new services developed by the construction and facilities management sectors. Most of all calculators, analyzers, software, decision support and expert systems, neural networks and on-line systems seek to find out how to make the most economic decisions and most of all these decisions are intended only for economic objectives. Alternatives under evaluation have to be evaluated not only from the economic position, but take into consideration qualitative, technical, technological and other characteristics as well. Based on the analysis of the existing calculators, analyzers, information, expert and decision support systems, neural networks and in order to determine most efficient versions of best practices a Decision Support Web-Based System for Construction Innovation (IDSS) was developed by Vilnius Gediminas Technical University.
Die Gesamtheit der Produktinformationen im Bauwesen stellt sich als sehr inkonsistente und redundante Informationsmenge dar. Die Hersteller stehen vor der Aufgabe, diese Produktinformationen nicht nur in der üblichen Katalogform sondern auch in neuen Medien wie CD-ROM und WWW zu publizieren. Einmal betriebener Erfassungsaufwand muß sich dabei durch eine einfache Mehrfachverwendung der Daten rentieren. Wegen seiner technologischen Eigenschaften eignet sich das WWW sehr gut als primäre Quelle für Produktinformationen. Vor allem wegen der möglichen Aktualität sollte es Grundlage für Publikationen in den anderen Medien sein. Mit verhältnismäßig geringem Aufwand lassen sich die WWW-Präsentation von Produktdaten so strukturieren, daß eine automatisierte Erfassung und Verarbeitung dieser Daten vereinfacht wird. So kann die Datenkonsistenz von der visuellen Präsentation in herkömmlichen Katalogen bis zur automatisch erstellten Produktdatenbank durchgängig gesichert werden. Vor dem Hintergrund der von Schnittstellenproblemen, heterogener Softwarestruktur und unzureichender Ausnutzung der Möglichkeiten der Informatik gekennzeichneten Situation im Bauwesen wird in generalisierter Ansatz mittels SGML vorgestellt. Mit einem derartigen Datenangebot werden neue, verteilte und vernetzte Anwendungen auf Grundlage derselben Produktdaten ermöglicht.
The phenomenological and computational aspects of the various damage models applications for the low and multi cyclic fatigue processes are investigated. Damage is considered as internal state variable, describing macroscopic effects of the progressive material degradation, within the framework of continuum damage mechanics. Present analysis is restricted to the case of isotropic damage, which can be modeled by a scalar variable. The strain, force and power types of kinetic equations for the damage evolution description are considered. The original mixed strain-power type damage model is developed for taking into account the different physical fracture mechanism in monotone and cyclic loading. The constitutive equations of plastic flow theory coupled and uncoupled to damage has been considered. The rational algorithm of implementation into finite element code is considered for developed damage models. Set of the computational experiments has been carried out for the various structures (huge aerials, pipelines, fastening units, vessel of nuclear reactor) and cases of loading. The comparison of the predictions of the developed model with experimental data is performed for 1X18H10T steel tubular specimens for complex paths of loading and for complex profiles beams under cyclic loading. Damage field distribution is the basic information for the prediction of crack initiation in structures. The developed method of structural parameter for stress concentration zones is discussed for correcting of crack location. It allows to describe the crack initiation near surface domain as observe in numerous experiments.
The problem of the computation of stresses and settlements in the half-space under various types of loads is often presented in geotechnical engineering. In 1885 Boussinesq advanced theoretical expressions to determine stresses at a point within an ideal mass. His equation considers a point load on the surface of a semi-infinite, homogeneous, isotropic, weightless, elastic half-space. Newmark in 1942 performed the integration of Boussinesq's equations for the vertical stress under a corner of a rectangular area loaded with a uniform load. The problem of the determination of vertical stresses under a rectangular shaped footing has been satisfactorily solved with renewal integration of the Boussinesq's equation over the arbitrary rectangle on surface of the half-space, with a non-uniform load represented with piecewise linear interpolation functions. The problem of the determination of stresses in the case when the footing shape is an arbitrary quadrilateral however remains unsolved. The paper discusses an approach to the computation of vertical stresses and settlements in an arbitrary point of the half-space, loaded with a uniform load, which shape in the ground plan can be a general four noded form with straight edges. Since the form is transformed into a biunit square and all integrations are performed over this area, all solutions are valid also for an arbitrary triangle by the implementation of the degeneration rule.
Civil engineering decision support systems (construction, building life cycle, refurbishment, total quality management, innovation, etc.) created in Lithuania are described in this paper. The above decision support systems comprise of the following constituent parts: data (database and its management system), models (model base and its management system) and a user interface. Presentation of information in databases may be in conceptual (digital, textual, graphical, photographic, video) and quantitative forms. Quantitative information presented involves criteria systems and subsystems, units of measurement, values and initial weight fully defining the variants provided. The databases were developed providing a multiple criteria analysis of alternatives from economical, infrastructure, technical, technological, qualitative, legislative, social and other perspectives. This information is provided in a user-oriented way. Since the analysis of alternatives is usually performed by taking into account economical, infrastructure, technical, technological, qualitative and other factors, a model-base include models which enable a decision maker to carry out a comprehensive analysis of the variants available and make a proper choice. These systems, related questions and practical case study were analysed the paper.
Building Information Modeling is a powerful tool for the design and for a consistent set of data in a virtual storage. For the application in the phases of realization and on site it needs further development. The paper describes main challenges and main features, which will help the development of software to better service the needs of construction site managers
There exists a big gap between the capabilities of current 3D-CAD applications and their actual usage in practice. Many architects and planners still prefer to draft in 2D because the benefits of 3D modeling are difficult to explain. This presentation offers a basis to view the 3D building model not merely as the source for 2D plan generation. By adding extra dimensions like Time and Cost to the 3D building model it becomes possible to generate dynamic information on building construction progress with regards to used material, resources and cost. These additional benefits are key elements to many planners and contractors and may therefore widen the acceptance of 3D building modeling in general.
Bauwerke sind in ihrer Betriebszeit vielen nutzungseinschränkenden Einflüssen ausgesetzt. Die dadurch erforderliche Instandhaltung dient zur Gewährleistung und zur Erhöhung der geplanten Nutzungsfähigkeit sowie Dauerhaftigkeit von Bauwerken. Sie spielt eine immer größere Rolle im Bauwesen. Die Kosten der Bauwerksinstandhaltung betragen je nach Art des Bauwerkes in Deutschland pro Jahr ca. 1-6% des Wiederbeschaffungswertes. Die Reduzierung des Instandhaltungsaufwandes durch Technik- und Management-Maßnahmen ist daher wirtschaftlich sinnvoll. Der Einsatz moderner Informations- und Kommunikationstechnologie auf dem Gebiet der Bestandsaufnahme und -analyse ist erforderlich, um einerseits die Bearbeitung von multimedialen Informationen über Ist- und Soll-Zustände von Bauwerken effektiver durchzuführen und um andererseits die Analyse von Schäden im Sinne einer Entscheidungshilfe zu unterstützen. Durch den Einsatz der WWW-Technologie kann die Bearbeitung auch verteilt im Datennetz über ferne Rechner hinweg erfolgen. Im Beitrag werden die Konzeptionierung und Implementierung des WWW-fähigen DV-Systems BINAS zur Unterstützung der Bestandsaufnahme und -analyse sowie die dafür erforderlichen Methoden und Werkzeuge vorgestellt.
Neben der reinen Bauausführung und den damit verbundenen Roh- und Ausbaukosten stellt insbesondere die Bewirtschaftung von Gebäuden einen wesentlichen Kostenfaktor dar, den zu minimieren Ziel der Bestrebungen auf dem Gebiet des Facilities Management ist. Insbesondere die Integration der verteilt vorliegenden Informationen muß hierbei das Ziel sein, um durch effiziente Informationsverarbeitung eine Einsparung von Unterhaltskosten zu erreichen. Bereits in der Planungsphase lassen sich die späteren Kosten für die Bewirtschaftung modellieren. Dies gilt auch für die Modellierung des Energiehaushaltes von Gebäuden. Für die Modellierung des Wärmeschutzes und der damit verbundenen Ermittlung des Heizenergiebedarfs werden z.Zt. starke Vereinfachungen getroffen, die durch die aktuelle Wärmeschutzverordnung vorgegeben sind, so daß die errechneten Werte meist sehr ungenau sind. Für eine DV-gerechte Modellierung eines Gebäudes während seiner Bewirtschaftung reichen herkömmliche CAD-Systeme nicht aus, da das Modell verschiedene Sichten zulassen muß: Neben einer bauteilorientierten Sicht muß auch eine raumorientierte Sicht vorgehalten werden, damit eine Modellierung von flächenbezogenen Parametern wie z.B. Kosten möglich wird. Dieser Beitrag zeigt einen Ansatz, der eine intensive Nutzung heterogener Ressourcen und Informationen auf der Grundlage eines dreidimensionalen Gebäudemodells ermöglicht. Exemplarisch für die Bereiche Raummanagement (im Sinne von kosten- und nutzungsorientierter Bestandsverwaltung) und Bauphysik wird dieser Ansatz erläutert und die Eingliederung dieser Teilgebiete der Bestandsverwaltung und -bewirtschaftung in ein Gesamtsystem aufgezeigt.
A wide variety of behavioural models exist in microscopic traffic simulation. Commercial programms often use closed-source policies and are confined to their respective simulation platforms. Open-source approaches mainly focus on distinctive, highly specialized traffic situations. In the scope of this paper, an open-source framework for developing modular, objectoriented simulation systems is presented, capable of simultaneously accommodating different driving models and enabling the user to modify and extend the catalogue of driving behaviours. The existing driving behaviours and the computational implementation of the simulation are being described.
The goal of the research is the development of a computer system to plan, simulate and visualize erection processes in construction. In the research construction cranes are treated as robots with predefined degrees of freedom and crane-specific motion planning techniques are developed to generate time-optimized and collision-free paths for each piece to be erected in the project. Using inverse kinematics and structural dynamics simulation, the computer system then computes the crane motions and velocities necessary to achieve the previously calculated paths. The main benefits of the research are the accurate planning and scheduling of crane operations leading to optimization of crane usage and project schedules, as well as improving overall crane safety in the project. This research is aimed at the development of systems that will allow computer-assisted erection of civil infrastructure and ultimately to achieve fully-automated erection processes using robotic cranes...
Creation of hierarchical sequence of the plastic and viscoplastic models according to different levels of structure approximations is considered. Developed strategy of multimodel analysis, which consists of creation of the inelastic models library, determination of selection criteria system and caring out of multivariant sequential clarifying computations, is described. Application of the multimodel approach in numerical computations has demonstrated possibility of reliable prediction of stress-strain response under wide variety of combined nonproportional loading.
This paper presents the combination of two different parallelization environments, OpenMP and MPI, in one numerical simulation tool. The computation of the system matrices and vectors is parallelized with OpenMP and the solution of the system of equations is done with the MPIbased solver MUMPS. The efficiency of both algorithms is shown on several linear and nonlinear examples using the Finite Element Method and a meshless discretization technique.
This paper presents an agent-based software, Virtual Administrator System (VAS) for the smallscale maintenance of school buildings. VAS is capable of handling a heavy load of routine, lowtech maintenance jobs. It assigns a different priority to each job application according to its significance and urgency, and automatically adjusts schedules for maintenance engineers when on-site supervision is needed. The system can help ease off the burden of routine small-scale maintenance work, making it more cost-effective and efficient in the overall management of school building maintenance. VAS posts jobs on the Web in a multi-media format and classified all applications into four categories: the on-call maintenance contract, the term maintenance contract, the guaranty maintenance contract, and the regular maintenance contract. It then estimates their urgency level and passes the information to maintenance engineers who will decide whether on-site inspection is needed. Based on the engineers’ feedback, VAS automatically implements the scheduling for inspection as well as sends out real-time or batch notifications to contractors. All these activities are recorded in a database to allow continuous research and data mining and the analysis and diagnosis of specific jobs for followup maintenance plans.
Die d - Dirac - Funktion d(x-xi) und Heviside - Funktion wurden vor allem zur Beschreibung diskontinuierlicher Belastungsfunktionen von gebogenen Balken angewendet. Im Referat werden die mathematischen Operationen auf den erwähnten Funktionen dargestellt. Darüber hinaus wird die Möglichkeit eindeutiger Aufschreibung von belibigen Belestungsfunktionen vorgeschlagen, die fast alle Fälle der in der Ingenieurpraxis auftretenden Belastungen umfassen. Die vorgeschlagenen Lösungen geben die Möglichkeit leichter Aufschreibung im Form eines Algorithmus, das die Ausnutzung von Komputertechnik in statischen Berechnungen ermöglicht. Am Ende des Referates werden die Zahlebeispiele dargestellt, die die Möglichkeiten praktischer Anwendungen der besprochenen Funktionen darstellen.
Individual views on a building product of people involved in the design process imply different models for planning and calculation. In order to interpret these geometrical, topological and semantical data of a building model we identify a structural component graph, a graph of room faces, a room graph and a relational object graph as aids and we explain algorithms to derive these relations. The application of the technique presented is demonstrated by the analysis and discretization of a sample model in the scope of building energy simulation.
This paper presents an evaluation system for steel structures of hydroelectric power stations, including hydraulic gates and penstocks, based on Fault Tree Analyasis (FTA) and performance maps. This system consists of fault tree diagrams of FTA, performance maps, design and analysis systems, and engineerin databases. These four modules are integrated by appropriate hyperlinks so that the user of this system can use it easily and seamlessly. A well developed system was applied to some illustrative example cases, and they showed that the developed methodology and system worked well and the users found the system useful and effective for their maintenance tasks at powerstations.
Authors' own research in applied unicriterial and multicriterial optimisation of bar structures, and also an analysis of accessible bibliography on structural synthesis allows to present herein an attempt to define a general algorithm for proceeding in formulation of a structural optimisation problem. A practical aspect of such an algorithm consists, in author's opinion, in enabling a designer a correct creation of a mathematical model of synthesis problems, independently of known mathematical methods employed to looking for an unconditional extremum of function of several variables. A proposed algorithm is not a ready-for-use tool for solving all the optimisation problems, but it constitutes an easy-to-expand theoretical basis. This basis should allow a designer to create a proper set of compromises on the way to construct a mathematical model of a specific optimisation problem. The algorithm, presented in the paper, is constructed as a sequence of the one-after-another problem questions, on which the designer answers: yes or no, and a set of selections from the knowledge base consisting of the elements of an optimisation problem components. The order of making questions adopted by the authors in the algorithm is subjective, however it is supported by their experience, both in applied optimisation and in designing of structures like trusses or frames.
Framed-tube system with multiple internal tubes is analysed using an orthotropic box beam analogy approach in which each tube is individually modelled by a box beam that accounts for the flexural and shear deformations, as well as the shear-lag effects. A simple numerical modeling technique is proposed for estimating the shear-lag phenomenon in tube structures with multiple internal tubes. The proposed method idealizes the framed-tube structures with multiple internal tubes as equivalent multiple tubes, each composed of four equivalent orthotropic plate panels. The numerical analysis is based on the minimum potential energy principle in conjunction with the variational approach. The shear-lag phenomenon of such structures is studied taking into account the additional bending moments in the tubes. A detailed work is carried out through the numerical analysis of the additional bending moment. The moment factor is further introduced to identify the shear lag phenomenon along with the additional moment.
Expert systems integrating fuzzy reasoning techniques represent a powerful tool to support practicing engineers during the early stages of structural design. In this context fuzzy models have proved themselves to be very suitable for the representation of complex design knowledge. However their definition is a laborious task. This paper introduces an approach for the design and the optimization of fuzzy systems based upon Genetic Programming. To keep the emerging fuzzy systems transparent a new framework for the definition of linguistic variables is also introduced.
An architecture of a distributed planning system for the building industry has been developed. The emphasis is on highly collaborative environments in steelwork, timber construction etc. where designers concurrently handle 3D models. The overall system connects local design systems by the so-called Design Framework DFW. This framework consists of the definition of distributed components and protocols which make the collaborative design work. The process of collaborative design has been formalized on an abstract level. This paper describes how this has been done. A sample is given to illustrate the mapping of concrete scenarios of the ‘real design world’ to an abstract scenario level. This work is funded by the Deutsche Forschungsgemeinschaft DFG as part of the project SPP1103 (Meißner et al. 2003).
In this Paper, we explored the relation between the electricity consumption in residential sector and the automobile energy consumption in transportation sector in accordance with the location of city by employing Geographic Information System (GIS). We found in the study that the electricity consumption per capita has a tendency that is higher in city center and lower in suburbs in Utsunomiya city. It is also noted that there is little difference among total consumption between city center and suburbs, despite the fact that the density of electric appliances tends to increase in a small size house of city center and the amount of automobile energy consumption from residence is lower in city center than in suburbs.
This paper presents a new design environment based on Multi-Agents and Virtual Reality (VR). In this research, a design system with a virtual reality function was developed. The virtual world was realized by using GL4Java, liquid crystal shutter glasses, sensor systems, etc. And the Multi-Agent CAD system with product models, which had been developed before, was integrated with the VR design system. A prototype system was developed for highway steel plate girder bridges, and was applied to a design problem. The application verified the effectiveness of the developed system.
Electric trains are considered one of the most eco-friendly and safest means of transportation. Catenary poles are used worldwide to support overhead power lines for electric trains. The performance of the catenary poles has an extensive influence on the integrity of the train systems and, consequently, the connected human services. It became a must nowadays to develop SHM systems that provide the instantaneous status of catenary poles in- service, making the decision-making processes to keep or repair the damaged poles more feasible. This study develops a data-driven, model-free approach for status monitoring of cantilever structures, focusing on pre-stressed, spun-cast ultrahigh-strength concrete catenary poles installed along high-speed train tracks. The pro-posed approach evaluates multiple damage features in an unfied damage index, which leads to straightforward interpretation and comparison of the output. Besides, it distinguishes between multiple damage scenarios of the poles, either the ones caused by material degradation of the concrete or by the cracks that can be propagated during the life span of the given structure. Moreover, using a logistic function to classify the integrity of structure avoids the expensive learning step in the existing damage detection approaches, namely, using the modern machine and deep learning methods. The findings of this study look very promising when applied to other types of cantilever structures, such as the poles that support the power transmission lines, antenna masts, chimneys, and wind turbines.
A Product Model of a Road
(1997)
Many errors and delays frequently appear when data is exchanged between particular tasks in the lifecycle of the road. Inter-task connections are therefore of great importance for the quality of the final product. The article describes a product model of a road wich is the kernel of an integrated information system intended to support all important stages of the road lifecycle: design, evaluation (through different analysis procedures), construction, and maintainance. Since particular tasks are often executed at different places and in different companies, the interconnections are supported by a special metafile which contains all specific data of the product model. The concept of the integrated system is object and component oriented. Additionally, existing conventional program packages are included to support some common tasks (methods). A conventional relational database system as well as an open spatial database system with the relevant GIS functionality are included to support the data structures of the model.
The displacements and stresses in arch dams and their abutments are frequently determined with 20-node brick elements. The elements are distorted near the contact plane between the wall and the abutment. A cantilever beam testbed has been developed to investigate the consequences of this distortion. It is shown that the deterioration of the accuracy in the computed stresses is significant. A compatible 18-node wedge element with linear stress variation is developed as an alternative to the brick element. The shape of this element type is readily adapted to the shape of the contact plane. It is shown that the accuracy of the computed stresses in the vicinity of the contact plane is improved significantly by the use of wedge elements.
Increasing complexity of today's buildings requires a high level of integration in the planning process. Common planning strategies, where individual project partners cooperate mainly to exchange results, are not suitable to jointly develop project goals and objectives. Integrated planning, a more holistic approach to deal with complex problems, is based on a high degree of communication amoung team members and leads to a goal oriented cooperation. Current approaches in the reasearch area of Computer Supported Cooperative Work (CSCW) poorly meet the requirements in planning. A planning process model, based on the principles of integrated planning will be introduced, aimed to provide the background for the implementation of a CSCW-platform.
A Multi-objective Model for Optimizing Construction Planning of Repetitive Infrastructure Projects
(2004)
This paper presents the development of a model for optimizing resource utilization in repetitive infrastructure projects. The model provides the capability of simultaneous minimization of both project duration and work interruptions for construction crews. The model provides in a single run, a set of nondominated solutions that represent the tradeoff between these two objectives. The model incorporates a multiobjective genetic algorithm and scheduling algorithm. The model initially generates a randomly selected set of solutions that evolves to a near optimal set of tradeoff solutions in subsequent generations. Each solution represents a unique scheduling solution that is associated with certain project duration and a number of interruption days for utilized construction crews. As such, the model provides project planners with alternative schedules along with their expected duration and resource utilization efficiency.
A comprehensive framework of information management system for construction projects in China has been established through extensive literature survey and field investigation. It utilizes the potential information technologies and covers the practical management patterns as well as the major aspects of construction project management. It can be used to guide and evaluate the design of the information management systems for construction projects in order to make the system to be applicable to a wide variety of construction projects and survive the changes in project management.
The synchronous distributed processing of common source code in the software development process is supported by well proven methods. The planning process has similarities with the software development process. However, there are no consistent and similarly successful methods for applications in construction projects. A new approach is proposed in this contribution.
Methods with the convergence order p 2 (Newton`s, tangent hyperbolas, tangent parabolas etc.) and their approximate variants are studied. Conditions are presented under which the approximate variants preserve their convergence rate intrinsic to these methods and some computational aspects (possibilities to organize parallel computation, globalization of a method, the solution of the linear equations versus the matrix inversion at every iteration etc.) are discussed. Polyalgorithmic computational schemes (hybrid methods) combining the best features of various methods are developed and possibilities of their application to numerical solution of two-point boundary-value problem in ordinary differential equations and decomposition-coordination problem in convex programming are analyzed.
The primary objective of initial shape analysis of a cable stayed bridge is to calculate initial installation cable tension forces and to evaluate fabrication camber of main span and pylon providing the final longitudinal profile of the bridge at the end of construction. In addition, the initial cable forces depending on the alternation of the bridge’s shape can be obtained from the analysis, and will be used to provide construction safety during construction. In this research, we conducted numerical experiments for initial shape of Ko-ha bridge, which will be constructed in the near future, using three different typical methods such as continuous beam method, linear truss method, and IIMF (Introducing Initial Member Force) method
Seit mehreren Jahren wird im Fachbereich Gestaltung, Studiengang Innenarchitektur 3D-Computergrafik und -animation in Lehrveranstaltungen ausgebildet und in Projekt- und Diplomarbeiten als Darstellungsmedium angewandt. Eine besondere Herausforderung stellen dabei die 3D-Visualisierungen von historischen Gebäuden dar. Mit den beiden nachfolgenden Beispielen soll der Einsatz und die curricularen Verknüpfung der CA-Technologie mit Studienarbeiten und Projekten zum Thema >Denkmalpflege< aufgezeigt werden. Rekonstruktion und Visualisierung des ehemaligen >Jagdschlosses Platte< bei Wiesbaden. Mit Unterstützung einer Kunsthistorikerin wurde in einer Studienarbeit das im Krieg zerstörte ehemalige Jagdschloß im Computer nachgebildet. Neben der Darstellung des Gebäudeäußeren und des zentralen Innenbereiches wurde eine Animation über die Triangulierung der klassizistischen Geometrie erstellt. Umnutzung historischer Bausubstanz am Beispiel der ehemaligen Klostersanlage >Schiffenberg< bei Gießen. Im Rahmen einer Projektarbeit wurden mehrer Konzepte entwickelt, Entwürfe erstellt und mittels Computeranimationen öffentlich präsentiert. In Kooperation mit dem Studiengang Fernsehtechnik (FH-Wiesbaden) wurde von zwei Studenten eine Videodokumentation über den gesamten Projektverlauf erstellt. Neben dem Aufzeigen der Arbeitsprozesse und dem Vorstellen des Lehrkonzeptes für die curriculare Einbindung der CA-Technologie werden aktuelle Studienergebnisse anhand von Videoprojektionen vorgestellt.