Refine
Document Type
- Article (130) (remove)
Institute
- Professur Informatik im Bauwesen (130) (remove)
Keywords
- Bautechnik (20)
- Produktmodell (19)
- Finite-Elemente-Methode (17)
- Simulation (17)
- Lernendes System (15)
- Mehragentensystem (14)
- Modellierung (13)
- Physikalisches Verfahren (11)
- Bauwerk (9)
- CAD (8)
- Forschungskooperation (6)
- Dynamische Belastung (5)
- Optimierung (5)
- Verkehrsplanung (5)
- Baukonstruktion (4)
- Framework <Informatik> (4)
- Geoinformationssystem (4)
- Stadtplanung (4)
- Stahlbau (4)
- Wissensmanagement (4)
- API (3)
- Bauwesen (3)
- Bauzeichnung (3)
- Computerunterstütztes Verfahren (3)
- Dreidimensionales Modell (3)
- Facility-Management (3)
- Fuzzy-Logik (3)
- Graphentheorie (3)
- Ingenieurbau (3)
- Tragwerk (3)
- Virtuelle Realität (3)
- Anwendung (2)
- Architektur (2)
- Balken (2)
- Bauindustrie (2)
- Bauschaden (2)
- Baustatik (2)
- Brückenbau (2)
- Datenaustausch (2)
- Datenmodell (2)
- Dialogsystem (2)
- Elastoplastizität (2)
- Entscheidungsunterstützungssystem (2)
- Europa (2)
- Festkörpermechanik (2)
- Forschung (2)
- Freie Schwingung (2)
- Geschichtetes Medium (2)
- Informationstechnik (2)
- Instandhaltung (2)
- Internet (2)
- Langzeitverhalten (2)
- Mathematisches Modell (2)
- Skelettbau (2)
- Stabilität (2)
- Standardisierung (2)
- Straßenbau (2)
- Visualisierung (2)
- Wissensverarbeitung (2)
- Öffentlicher Personennahverkehr (2)
- Ablaufplanung (1)
- Ausschreibung (1)
- Autobahn (1)
- Bandmatrix (1)
- Bauaufnahme (1)
- Bauausführung (1)
- Bauinformatik (1)
- Bauplanung (1)
- Bauteil (1)
- Bauwerksplanung (1)
- Bauzustand (1)
- Bedarfsforschung (1)
- Belastung (1)
- Beltrami-Gleichung (1)
- Beschränkung (1)
- Bewertung (1)
- Bildanalyse (1)
- Boden-Bauwerk-Wechselwirkung (1)
- Bodenmechanik (1)
- Brandschutz (1)
- Bruchmechanik (1)
- Computer Supported Cooperative Work (1)
- Computergraphik (1)
- Construction Sequence (1)
- Dammbau (1)
- Datenbank (1)
- Datenbanksystem (1)
- Datenbankverwaltung (1)
- Diskrete Optimierung (1)
- EXPRESS <Programmiersprache> (1)
- Eigenwert (1)
- Elastomer (1)
- Entscheidung bei mehrfacher Zielsetzung (1)
- Fraktal (1)
- Genetischer Algorithmus (1)
- Gittererzeugung (1)
- Gleichgewicht (1)
- Green-Funktion (1)
- Grenzzustand (1)
- Halbraum (1)
- Heuristik (1)
- Hochhaus (1)
- Holzbau (1)
- Hängebrücke (1)
- Informationsmanagement (1)
- Infrastruktur (1)
- Ingenieurholzbau (1)
- Integrierte Planung (1)
- Isotropie (1)
- Kartierung (1)
- Katastrophenmanagement (1)
- Kennzahl (1)
- Kette (1)
- Klein- und Mittelbetrieb (1)
- Kommunikationsprotokoll (1)
- Konzipieren <Technik> (1)
- Lebenszyklus (1)
- Lebenszyklus <Wirtschaft> (1)
- Luft (1)
- Managementinformationssystem (1)
- Markowschke (1)
- Mehrdimensionalität (1)
- Mustererkennung (1)
- Nichtlineares Phänomen (1)
- Numerisches Verfahren (1)
- Objektmodell (1)
- Objektorientiertes Datenbanksystem (1)
- Parallelverarbeitung (1)
- Parameteridentifikation (1)
- Pflasterungen (Mathematik) (1)
- Photogrammetrie (1)
- Plastizitätstheorie (1)
- Platte (1)
- Produktinformation (1)
- Programm (1)
- Projektdokumentation (1)
- Quantenphysik (1)
- Quaternion (1)
- Rekonstruktion (1)
- Ressourcenallokation (1)
- Rissbildung (1)
- STEP (1)
- Schadstoffkonzentration (1)
- Schulgebäude (1)
- Schwingung (1)
- Setzung (1)
- Shore Spacing (1)
- Shore Stiffness (1)
- Shoring System (1)
- Sicherheit (1)
- Software (1)
- Spannender Baum (1)
- Spannung (1)
- Stabwerk (1)
- Stadtverkehr (1)
- Stahlbeton (1)
- Stahlbrücke (1)
- Stahlkonstruktion (1)
- Standard (1)
- Stapelproblem (1)
- Statik (1)
- Stochastisches Modell (1)
- Stoffgesetz (1)
- Stokes-Problem (1)
- Straße (1)
- Straßenbrücke (1)
- Straßenkarte (1)
- Strukturanalyse (1)
- Teamwork (1)
- Temperatur (1)
- Tragwerk / Vorspannung (1)
- Trajektorie (Mathematik) (1)
- Transport (1)
- Transportproblem (1)
- Trägheit (1)
- Tunnel (1)
- Turmdrehkran (1)
- Vektorfunktion (1)
- Verbundtragwerk (1)
- Verkehrsaufkommen (1)
- Verkehrsmittelwahl (1)
- Verkehrsnetz (1)
- Versionsverwaltung (1)
- Versorgungsnetz (1)
- Verteiltes Datenverarbeitungssystem (1)
- Verteiltes System (1)
- Viskoplastizität (1)
- Vorgespannte Konstruktion (1)
- Vorspannung (1)
- Wartezeit (1)
- Wasserkraftwerk (1)
- Wechselwirkung (1)
- Wirtschaftlichkeit (1)
- Zufallsvariable (1)
- Zuverlässigkeit (1)
- Zuverlässigkeitstheorie (1)
- cable force (1)
- cable stayed bridge (1)
- initial equilibrium state (1)
- initial shape (1)
In this paper we present a computer aided method supporting co-operation between different project partners, such as architects and engineers, on the basis of strictly three-dimensional models. The center of our software architecture is a product model, described by the Industry Foundation Classes (IFC) of the International Alliance for Interoperability (IAI). From this a geometrical model is extracted and automatically transferred to a computational model serving as a basis for various simulation tasks. In this paper the focus is set on the advantage of the fully three-dimensional structural analysis performed by p-version of the finite element analysis. Other simulation methods are discussed in a separate contribution of this Volume (Treeck 2004). The validity of this approach will be shown in a complex example.
We consider the standardization problem (SP) which can be formulated as follows. It is known demand bi in each type i in {1, 2, ..., n} of items. Production of yi items of the ith type brings a profit fi (yi), where fi is a nondecreasing concave function for each i in {1, 2, ..., n}.It is necessary to satisfy the demand and to maximize the total profit provided that there exist >standardization possibilities< . These possibilities means that some types of items can be replaced by some another types. We introduce generalized standardization problem (GSP) in which titems demand is given as the set of admissible demand vectors. We show that GSP and SP are special cases of the resource allocation problem over a network polymatroid. Ibasing on this observation we propose a polynomial time solution algorithm for GSP and SP.
Eine der wichtigsten Aufgaben und Herausforderungen der Bauinformatik ist gegenwärtig die Realisierung des durchgängigen, fachübergreifenden Datenflusses im Planungsprozeß eines Bauvorhabens. Im Hinblick auf die internationale Wettbewerbsfähigkeit der deutschen Bauwirtschaft ist es unumgänglich, vorhandene Effizienzpotentiale in der Bauplanung auszuschöpfen, welche durch eine qualitative Verbesserung der Planung sowie durch eine Verringerung der Bearbeitungszeit aller beteiligten Fachplanern erreicht werden können. Nach dem gegenwärtigen Stand der Technik werden die Informationsobjekte standardisiert, damit sie durchgängig nutzbar sind. Diese werden in einem allgemeingültigen Format den speziellen Programmen der Fachplaner zur Verfügung gestellt. In dieser Arbeit wird der Ansatz verfolgt, eine Integration durch die Standardisierung der Kommunikation zwischen den Informationsobjekten und ihren Anwendungsprogrammen zu erreichen. Dabei kann auf die Standardisierung der zu übertragenden Objekte verzichtet werden. Ziel der Ausarbeitung ist die Definition von implementationstechnischen Regeln, die alle auszutauschenden Objekte sowie die Anwendungen, die solche Objekte aufnehmen wollen, erfüllen müssen. Die Bearbeitung der Objekte soll in den gewohnten Anwendungen in unveränderter Weise erfolgen.
The frame of this paper is the development of methods and procedures for the description of the motion of an arbitrary shaped foundation. Since the infinite half-space cannot be properly described by a model of finite dimensions without violating the radiation condition, the basic problems are infinite dimensions of the half-space as well as its non-homogeneous nature. Consequently, an approach has been investigated to solve this problem indirectly by developing Green's function in which the non-homogeneity and the infiniteness of the half-space has been included. When the Green's function is known, the next step will be the evaluation of contact stresses acting between the foundation and the surface of the half-space through an integral equation. The equation should be solved in the area of the foundation using Green's function as the kernel. The derivation of three-dimensional Green's function for the homogeneous half-space (Kobayashi and Sasaki 1991) has been made using the potential method. Partial differential equations occurring in the problem have been made ordinary ones through the Hankel integral transform. The general idea for obtaining the three-dimensional Green's function for the layered half-space is similar. But in that case some additional phenomena may occur. One of them is the possibility of the appearance of Stonely surface waves propagating along the contact surfaces of layers. Their contribution to the final result is in most cases important enough that they should not be neglected. The main advantage of results presented in comparing to other obtained with numerical methods is their accuracy especially in the case of thin layers because all essential steps of Green's function evaluation except of the contour integration along the branch cut have been made analytically. On the other hand the disadvantage of this method is that the mathematical effort for obtaining the Green's function is increasing drastically with the increase of the number of layers. Future work will therefore be directed in simplifying of the above described process
SLang - the Structural Language : Solving Nonlinear and Stochastic Problems in Structural Mechanics
(1997)
Recent developments in structural mechanics indicate an increasing need of numerical methods to deal with stochasticity. This process started with the modeling of loading uncertainties. More recently, also system uncertainty, such as physical or geometrical imperfections are modeled in probabilistic terms. Clearly, this task requires close connenction of structural modeling with probabilistic modeling. Nonlinear effects are essential for a realistic description of the structural behavior. Since modern structural analysis relies quite heavily on the Finite Element Method, it seems to be quite reasonable to base stochastic structural analysis on this method. Commercially available software packages can cover deterministic structural analysis in a very wide range. However, the applicability of these packages to stochastic problems is rather limited. On the other hand, there is a number of highly specialized programs for probabilistic or reliability problems which can be used only in connection with rather simplistic structural models. In principle, there is the possibility to combine both kinds of software in order to achieve the goal. The major difficulty which then arises in practical computation is to define the most suitable way of transferring data between the programs. In order to circumvent these problems, the software package SLang (Structural Language) has been developed. SLang is a command interpreter which acts on a set of relatively complex commands. Each command takes input from and gives output to simple data structures (data objects), such as vectors and matrices. All commands communicate via these data objects which are stored in memory or on disk. The paper will show applications to structural engineering problems, in particular failure analysis of frames and shell structures with random loads and random imperfections. Both geometrical and physical nonlinearities are taken into account.
Die Sicherheit von Tragwerken hängt von der zuverlässigen Modellierung sämtlicher Tragwerksparameter ab. Üblicherweise werden diese Parameter als deterministische oder stochastische Größen beschrieben. Stochastische Größen sind Zufallsgrößen, die unscharfe Informationen über Tragwerksparameter mit Hilfe von Dichtefunktionen erfassen. Nicht alle unscharfen Tragwerksparameter lassen sich als Zufallsgrößen darstellen. Sie können jedoch als Fuzzy-Größen modelliert werden. Fuzzy-Größen beschreiben unscharfe Tragwerksparameter als unscharfe Menge mit Bewertungsfunktion (Zugehörigkeitsfunktion). Die Fuzzy-Modellierung im Bauingenieurwesen umfaßt die Fuzzifizierung, die Fuzzy-Analyse, die Defuzzifizierung und die Sicherheitsbeurteilung. Sie erlaubt es, Tragwerke mit nicht-stochastischen unscharfen Eingangsinformationen zu untersuchen. Nicht-stochastische Eingangsinformationen treten sowohl bei bestehenden als auch bei neuen Tragwerken auf. Die unscharfen Ergebnisse der Fuzzy-Modellierung gestatten es, das Systemverhalten zutreffender zu beurteilen; sie sind die Ausgangspunkte für eine neue Sicherheitsbeurteilung auf der Grundlage der Möglichkeitstheorie. Bei der Fuzzy-Analyse ist die alpha-Diskretisierung vorteilhaft einsetzbar. Bei fehlender Monotonie der deterministischen Berechnungen und unter Berücksichtigung der Nichtlinearität wird die Fuzzy-Analyse mit Optimierungsalgorithmen durchgeführt. Zwei Beispiele werden diskutiert: die Lösung eines transzendenten Eigenwertproblems und eines linearen Gleichungssystems. Die Systemantworten der Fuzzy-Analyse werden der Sicherheitsbeurteilung zugrunde gelegt. Für ausgewählte physikalische Größen werden Versagensfunktionen definiert. Diese bewerten die Möglichkeit des Versagens. Mit Hilfe von Min-max-Operationen der Fuzzy-Set-Theorie erhält man aus Versagensfunktion und Fuzzy-Antwort die Versagensmöglichkeit bzw. die Überlebensmöglichkeit. Die ermittelte Versagensmöglichkeit repräsentiert die subjektive Beurteilung der Möglichkeit, daß das Ereignis &qout;Versagen&qout; eintritt. Beispiele zeigen die Unterschiede zwischen der Sicherheitsbeurteilung mittels Fuzzy-Modells und mittels deterministischen Modells.
This work was partially supported by DAAD, Fundamental Researches Foundation of Belarus and International Soros Science Education Program We consider a vector discrete optimization problem on a system of non- empty subsets (trajectories) of a finite set. The vector criterion of the pro- blem consists partial criterias of the kinds MINSUM, MINMAX and MIN- MIN. The stability of eficient (Pareto optimal, Slater optimal and Smale op- timal) trajectories to perturbations of vector criterion parameters has been investigated. Suficient and necessary conditions of eficient trajectories local stability have been obtained. Lower evaluations of eficient trajectories sta- bility radii, and formulas in several cases, have been found for the case when l(inf) -norm is defined in the space of vector criterion parameters.
O-D Matrix sind die wichtigste Informationsquelle, die den Bedarf an Transport in der Stadt betrifft. Sie dienen den richtigen Bildung von Straßennetz und Öffentlichen Personen Verkehrslinien. Anhand diesen Grundlagen gerechnet man Verkehrsstärken, die zur Dimensionierung der Verkehrsinfrastruktur benutzt werden. Im Verkehrsplannung zur Rechnung O-D Matrix wird Vier - Stufen - Methode angewendet. In dieser Methode verwendet man die Angaben aus den Haushaltsumfragen und aus den Kordonumfragen. Diese Methode fordert einen großen Arbeitsaufwand und Kosten. Hier wird die andere Methode dargestellt. Bei Schätzung der O-D Matrix verwendet man die Verkehrsstärken, die in den Straßenquerschnitten gemessen werden. Wir brauchen gemessene Verkehrsstärken auch für andere Ziele (z. B. für Signalsteuerung, für Beobachtung des Motorisierungstrendes). Darum ist diese Methode billiger als das traditionelle Verfahren. In diesen Methode haben wir zwei Möglichkeiten. Die erste - von Verkehrsstärkemessungen kann man O-D Matrix direkt schätzen. Und zweite Möglichkeit - zuerst rechnen wir die Verkehrserzeugungen und später O-D Matrix. Das zweite Verfahren hat einen wesentlichen Vorteil und zwar, anhand der Verkehrserzeugungen ist es möglich alle Elemente O-D Matrix zu rechnen. Bei der Schätzung der O-D Matrix unmittelbar von den Messungen (das erste Verfahren) bekommt man nur diese Elemente, die in den beobachtenen Straßenquerschnitten auftreten.
This paper presents an application of dynamic decision making under uncertainty in planning and estimating underground construction. The application of the proposed methodology is illustrated by its application to an actual tunneling project—The Hanging Lake Tunnel Project in Colorado, USA. To encompass the typical risks in underground construction, tunneling decisions are structured as a risk-sensitive Markov decision process that reflects the decision process faced by a contractor in each tunneling round. This decision process consists of five basic components: (1) decision stages (locations), (2) system states (ground classes and tunneling methods), (3) alternatives (tunneling methods), (4) ground class transition probabilities, and (5) tunneling cost structure. The paper also presents concepts related to risk preference that are necessary to model the contractor’s risk attitude, including the lottery concept, utility theory, and the delta property. The optimality equation is formulated, the model components are defined, and the model is solved by stochastic dynamic programming. The main results are the optimal construction plans and risk-adjusted project costs, both of which reflect the dynamics of subsurface construction, the uncertainty about geologic variability as a function of available information, and the contractor’s risk preference.
Recently, many reseraches on active control systems of building structures are preformed based on modern control theory and are installed real buildings. The authors have already proposed intelligent fuzzy optimal active control (IFOAC) systems. IFOAC systems imitate intelligent activities of human brains such as prediction, adaptation, decision-kaking and so on. In IFOAC systems, objective and subjective judgements on the active control can be taken into account. However, IFOAC systems are considered to be suitable for far-field erathquake and control effect becomes small in case of near-field earthqaukes which include a few velosity pules with large amplitudes. To improve control effect in case of near-souece earthquakes, the authors have also proposed hybrid control (HC) systems, in which IFOAC systems and fuzzy control system are combined. In HC systems, the fuzzy control systems are introduced as a reflective fuzzy active control (RFAC) system and imitates spinal reflection of human. In HC systems, active control forces are activated to buildings in accordance with switching rules on active control forces. In this paper, optimizations on fuzzy control rules in RFAC system and switching rules of active control forces in HC system are performed by Parameter-Free Genetic Algorithms (PfGAs). Here, the optimization is performed by using different earthquake inputs. The results of digital simulations show that the HC system can reduce maximal response displacements under restrictions on strokes of the actuator effectively in case of a near-source earthquake and the effectiveness of the proposed HC system is discussed and clarified.
Research on Establishment of a Standard of Traffic Impact Assessment with Integrated Database System
(2004)
Planning support systems, such as geographical information system (GIS) and traffic flow simulation models, are widely in use in recent urban planning research. In this paper we propose a method to apply traffic impact assessment (TIA) to large-scale, commercial developments. In TIA research we often encounter the problem of increasing amount of data that is necessary for detailed investigation and analysis, as the scale of commercial developments become larger and more complex. As a result, TIA presents two problems. The first problem is the difficulty of data acquisition. The second problem is the reliability of data. As a solution, we developed an integrated database system.
A multicriterial statement of the above mentioned problem is presented. It differes from the classical statement of Spanning Tree problem. The quality of solution is estimated by vector objective function which contains weight criteria as well as topological criteria (degree and diameter of tree). Many real processes are not determined yet. And that is why the investigation of the stability is very important. Many errors are connected with calculations. The stability analysis of vector combinatorial problems allows to discover the value of changes in the initial data for which the optimal solution is not changed. Furthermore, the investigation of the stability allows to construct the class of the problems on base of the one problem by means of the parameter variations. Analysis of the problems with belong to this class allows to obtaine axact and adecuate discription of model
The paper introduced the research and application of the highway construction management information integrated system. Explained the development and application of highway survey applet run on mobile telephone supporting Java and the technique of transmitting engineering data by GPRS wireless network technology. And expounded the development and application of highway engineering construction field data collecting software run on Pocket-PC. Recommended the technique of engineering long distance data transmitting based on C/S structure adopting VPN (Virtual Private Networks) technology. Especially expatiated on the research on the platform of highway construction management information integrated system adopting geography information system (GIS) technique, database technique and network technique. And said all to subsystem about bid manage, contract management, engineering design drawing, engineering survey calculation, measure and pay, data processing on engineering experiment, quantity assessing, project plan and progress, engineering document management etc. Besides? proposed highway construction project visual analysis and inquiry system based on Web-GIS; Explained the research and application of highway engineering construction OA based on B/S structure; real-time workflow and information processing such as the management of administration, business and procedure of authorization and information distribution. At last, the author described the prospect of the application of C/S and B/S structure in trade software development in the highway construction management.
In current AEC practice client requirements are typically recorded in a building program, which, depending on the building type, covers various aspects from the overall goals, activities and spatial needs to very detailed material and condition requirements. This documentation is used as the starting point of the design process, but as the design progresses, it is usually left aside and changes are made incrementally based on the previous design solution. These incremental small changes can lead to a solution that may no longer meet the original requirements. In addition, design is by nature an iterative process and the proposed solutions often also cause evolution in the client requirements. However, the requirements documentation is usually not updated accordingly. Finding the latest updates and evolution of the requirements from the documentation is very difficult, if not impossible. This process can lead to an end result, which is significantly different from the documented requirements. Some important requirements may not be satisfied, and even if the design process was based on agreed-upon changes in the scope and requirements, differences in the requirements documents and in the completed building can lead to well-justified doubts about the quality of the design and construction process...
Renovation's peculiarities of industrial enterprises in conditions of economic selfsufficiency
(1997)
Probleme of recrienfation of building complex, to the sharp increase of share of reconstruction works, capital repair and modernisation of in-dustrial plants are concidered in this work. The conception of develop-ment and creation of unitified system of expluatation and renovation of industrial plants are worded out. This system is based on date-computer technology and taking into conciderations of real economic relations.
The theory of random matrices, or random matrix theory, RMT in what follows, has been developed at the beginning of the fties to describe the sta- tistical properties of energy levels of complex quantum systems, [1], [2], [3]. In the early eighties it has enjoyed renewed interest since it has been recognized as a very useful tool in the study of numerous physical systems. Specically, it is very useful in the analysis of chaotic quantum systems. In fact, in the last years many papers appeared about the problem of quantum chaos which implies the quantization of systems whose underlying classical dynamics is irregular (i.e. chaotic). The simplest models considered in this eld are billi- ards of various shapes. From the the classical point of view, a point particle in a 2-dimensional billiard displays regular or irregular motion depending on the shape of the billiard; for instance motion in a rectangular or circular billi- ard is regular thanks to the symmetries of the boundary. On the other hand, billiards of arbitrary shapes imply chaotic motion, i.e. exponential diver- gence of initially nearby trajectories. In order to study quantum billiards we have to consider the Schroedinger equation in various 2-dimensional domains. The eigenvalues of the Schroedinger equation represent the allowed energy levels of our quantum particle in the billiard under consideration, while the eigenfunction norms represent the probability density of nding the particle in a certain position. The question of quantum chaos is whether the charac- ter of the classical motion (regular or chaotic) can in uence some properties
Pseudorigidity method for solving the problem of limit equilibrium of rigid-plastic constructions
(1997)
1.Design calculations , based upon the theory elasticity , cannot completely satisfy engineers and designers , because cannot answer to basic question about overload capability . Only design calculations of limit equilibrium of rigid-plastic constructions can answer to this question completely enough. As a rule , such design calculations are made issue from hypothesis, that material of construction has rigid-plastic diagram Prandtl .This scheme of calculation gives qualitatively more correct results, then usual calculation, based upon law Hooke’s , and allows more really estimate ultimate strength of construction due to different loads. Universal algorithms for solving the problem of limit equilibrium have been created since the middle of the 60’s.These algorithms are based upon two basic theorems about limit analysis - static and kinetics. It was found , that with the help of above-mentioned theorems the problem of limit equilibrium can be formulated as a problem of linear programming (for linear yield) or nonlinear programming (for yield Guber-Mizes). The method of linear programming conformably to calculation of rod systems got the most development in the reports Prager W. [1] and Chiras A. [ 2 ]. The method of linear programming conformably to plates and shells was widely used by Rganizin A.[3]. [3[ contains more full bibliography about this problem. Calculation of limit equilibrium with the help of linear and nonlinear programming has a few significant lacks: - complexity and laboriousness preliminary preparation of problem for PC; - necessity to use special program means , which are not in usual program packet for strength analysis. Author worked out a new method about design calculation of limit equilibrium without above-mentioned lacks . The method is based upon analogy of relations between internal generalized efforts and generalized deformations in elastic system and between generalized efforts and velocities of change generalized deformations in rigid-plastic system. Because later rigid-plastic deformation would be treated as an elastic deformation in the system with special constructed rigidities , this method could be called >pseudorigidity method<.
The Priority Programme ‘Network Based Co-operation in Structural Engineering’ of the ‘German Research Foundation’ (DFG) has been established in the year 2000. This paper describes and discusses the main research directions and first results of the workgroup ‘Distributed Product Models’. The five projects of the workgroup have developed completely different solutions for specific application domains. Each solution concept deals with a consistent product modeling and knowledge processing in a distributed environment in the planning process. The individual solution approaches of the projects are described and the underlying basic assumptions are discussed. A unified system architecture is described for all projects of the workgroup. Two different approaches (object-oriented and graph-based models) have been introduced for product and knowledge modeling. The common structure of these models will be explained to fully understand the differences of these modeling approaches. Finally the concepts for co-operative work and conflict management in a distributed environment are described: The solution approaches will be distinguished by classifying the supported co-operation according to time. A final scientific summary describes the state-of-the-art in network based co-operation in structural engineering: The role of research directions like knowledge modeling, standard product modeling and versioning in the distributed planning process will be explained.
The complexity of the relationships between the actors of a building project requires high efficiency in communication. Among other things, data sharing is crucial. The exchange of data is made possible by interfaces between expert programs, which rely on product models. The latter are neutral standards with formal definitions of building objects and their attributes. This paper deals with the state of the art and the research activities concerning product models in the steel construction domain and the advantages provided by this technology for the sector.