Refine
Document Type
- Conference Proceeding (51)
- Article (41)
- Doctoral Thesis (23)
- Master's Thesis (3)
- Bachelor Thesis (2)
- Periodical (2)
- Report (2)
- Book (1)
Institute
- Institut für Strukturmechanik (ISM) (40)
- In Zusammenarbeit mit der Bauhaus-Universität Weimar (18)
- Professur Angewandte Mathematik (9)
- Bauhaus-Institut für Geschichte und Theorie der Architektur und Planung (8)
- Professur Stochastik und Optimierung (7)
- F. A. Finger-Institut für Baustoffkunde (FIB) (6)
- Junior-Professur Computational Architecture (6)
- Institut für Europäische Urbanistik (5)
- Graduiertenkolleg 1462 (4)
- Professur Informatik im Bauwesen (4)
Keywords
- Angewandte Mathematik (65)
- Building Information Modeling (36)
- Angewandte Informatik (35)
- Computerunterstütztes Verfahren (35)
- Data, information and knowledge modeling in civil engineering; Function theoretic methods and PDE in engineering sciences; Mathematical methods for (robotics and) computer vision; Numerical modeling in engineering; Optimization in engineering applications (34)
- Strukturmechanik (31)
- Architektur (9)
- Städtebau (7)
- Stochastik (5)
- Architecture (2)
- Beton (2)
- Cement (2)
- Finite-Elemente-Methode (2)
- Informatik (2)
- Kulturwissenschaft (2)
- Luci (2)
- Manifest (2)
- Manifesto (2)
- Medienwissenschaft (2)
- Rezeption (2)
- Rezeptionssteuerung (2)
- Stadtplanung (2)
- Zement (2)
- architecture (2)
- distributed computing (2)
- middleware (2)
- Abwasserleitung (1)
- Actor-Network-Theory (1)
- Aerodynamic (1)
- Agrarprodukt (1)
- Akteur-Netzwerk-Theorie (1)
- Alkali silica reaction (1)
- Alkali-Kieselsäure-Reaktion (1)
- Alkalisilikat (1)
- Alkalislikat (1)
- Anthropologie (1)
- António de Oliveira Salazar (1)
- Apparatgeist-Theorie (1)
- Arbeitsrecht (1)
- Architectual lighting (1)
- Architektur der Moderne (1)
- Architekturgeschichte (1)
- Ausstellung (1)
- Ausstellungstheorie (1)
- BIM; Building Information Modeling; site management; construction site. (1)
- Bauphysik (1)
- Baustelle (1)
- Bauteil (1)
- Beleuchtung (1)
- Beschichtung (1)
- Betonstraße (1)
- Bindemittel (1)
- Bodengestaltung (1)
- Bornitrid (1)
- Brasilia (1)
- Brasilien (1)
- Brazil; collective; residences; families; neighbourhoods; new middle class; private; self-production; space; urban (1)
- CAAD (1)
- CAD (1)
- CFRP (1)
- Complexation (1)
- Computer (1)
- Conservation (1)
- DLVO-Theorie (1)
- Data, information and knowledge modeling in civil engineering (1)
- Dauerhaftigkeit (1)
- Design synthesis (1)
- Designgeschichte (1)
- Dictatorship (1)
- Duarte Pacheco (1)
- Eigenform (1)
- Encosta Da Ajuda/Restelo (1)
- Energieeinsparung (1)
- Europe (1)
- Evolutionary algorithm (1)
- Facility Management (1)
- Faltung (1)
- Faria Da Costa (1)
- Fascism (1)
- Fly ash (1)
- Fläche (1)
- Flächenallokation (1)
- Flächenmanagement (1)
- Flächenoptimierung (1)
- Flächensteuerung (1)
- Flächensteuerungsmodell (1)
- Flächenverteilung (1)
- Function theoretic methods and PDE in engineering sciences (1)
- GaBi Software (1)
- Gasverteilungsnetz (1)
- Gebäude (1)
- Gemeinschaftsgarten (1)
- Geographie (1)
- Gustavo Giovannoni (1)
- Hochschule (1)
- Holzbau (1)
- Homogenization (1)
- Hydration and microstructure (1)
- Individual Sociology (1)
- Information Visualization (1)
- Instandsetzung (1)
- Internal pozzolanic reactivity (1)
- Istanbul (1)
- Italy, Rome (1)
- Joseph Stübben (1)
- Kohlenstoff (1)
- Kohlenstofffaserverstärkter Kunststoff (1)
- Konservierung (1)
- Konstruktion (1)
- Kryptologie (1)
- Kultur (1)
- Kulturaustausch (1)
- Kulturerbe (1)
- Laser Scanner (1)
- Leichtbau (1)
- Leiharbeit (1)
- Limestone powder (1)
- Macro-mesoporous structure (1)
- Marcello Piacentini (1)
- Massendaten (1)
- Material (1)
- Materialität (1)
- Materialversagen (1)
- Mathematical methods for (robotics and) computer vision (1)
- Mathematik (1)
- Medien (1)
- Mittelstand (1)
- Mix design method (1)
- Multi-criteria (1)
- Multi-objective Evolutionary Optimization, Elitist Non- Dominated Sorting Evolution Strategy (ENSES), Sandwich Structure, Pareto-Optimal Solutions, Evolutionary Algorithm (1)
- Multiscale modeling (1)
- Nanocomposite materials (1)
- Nanoverbundstruktur (1)
- Nanowissenschaften (1)
- Numerical modeling in engineering (1)
- Nutzungsgrad (1)
- Optimierung (1)
- Optimization (1)
- Optimization in engineering applications (1)
- Outsourcing (1)
- Papierware (1)
- Particle size distribution (1)
- Perkolationstheorie (1)
- Plagiarism Visualization (1)
- Platte (1)
- Polymere (1)
- Preferential Choice (1)
- Product Search (1)
- Produktgestaltung (1)
- Radioastronomie (1)
- ReCiPe (1)
- Reception (1)
- Reparatur (1)
- Retardation (1)
- Rheological property (1)
- Rice husk ash (1)
- Rohrleitungsbau (1)
- Rohrnetz (1)
- Ruine (1)
- Sandwichbauteil (1)
- Sanierung (1)
- Schall (1)
- School Institution (1)
- Schwingung (1)
- Second World War (1)
- Seidenstraße (1)
- Self-compacting high performance concrete (1)
- Sensitivitätsanalyse (1)
- Setting agent (1)
- Silikat (1)
- Silikatbeschichtung (1)
- Simulation (1)
- Slag (1)
- Smartphone (1)
- Socio-spatiality (1)
- Socio-urban Exclusion (1)
- Spaziergang (1)
- Sprayed concrete (1)
- Spritzbeton (1)
- Spritzzement (1)
- Stadtgestaltung (1)
- Stadtsoziologie (1)
- Stahlbau (1)
- Stochastic analysis (1)
- Sulfatträger (1)
- Superplasticizer (1)
- Supplementary cementitious materials (1)
- Text-based Visualization (1)
- Tragendes Teil (1)
- Tricalcium silicate (1)
- Umbau (1)
- Umwandlung (1)
- Umweltbelastungspunkte (1)
- Umweltbilanz (1)
- Universität (1)
- Urban Heritage (1)
- Urban Social Movements (1)
- Urban Sociology (1)
- Urbanism (1)
- Urbanität (1)
- Verbund (1)
- Verbundwerkstoff (1)
- Versorgungsleitung (1)
- Vibrometer (1)
- Virtuelle Realität (1)
- Visualisierung (1)
- Vorspannung (1)
- Wasserglas (1)
- Wasserrohrnetz (1)
- Wellpappe (1)
- Werkstoffkunde (1)
- Wohnen (1)
- Wohnsitz (1)
- Wohnung (1)
- Wärmeleitfähigkeit (1)
- Xiyü-Kultur (1)
- Zementart (1)
- aerodynamic (1)
- affordance (1)
- alternative spaces (1)
- architecture, urbanism, dictatorship, Lisbon, Faria da Costa (1)
- asiatische Kultur (1)
- associative space (1)
- authenticated encryption (1)
- bridge (1)
- city extension (1)
- civic center (1)
- civic design (1)
- communal space (1)
- community gardens (1)
- composite (1)
- cplan (1)
- development (1)
- dictatorial design (1)
- dictatorship (1)
- discourse analysis (1)
- economic houses program (1)
- elasticity (1)
- external pozzolanic reactivity (1)
- facility management (1)
- gated community (1)
- geometry (1)
- harmonic (1)
- hash functions (1)
- higher education (1)
- housing typologies (1)
- human touch (1)
- inclusive design (1)
- industrialization (1)
- isogeometric methods (1)
- living heritage site (1)
- material (1)
- material failure (1)
- mathematics (1)
- media anthropology, anthropomediality, anthropological knowledge, museum exhibitions, diorama, relationality (1)
- multiscale (1)
- nanocomposite (1)
- password scrambler (1)
- pavement (1)
- policy objectives (1)
- political intention (1)
- politische Repräsentation (1)
- preservation (1)
- prestress (1)
- provable security (1)
- quaternion (1)
- reception (1)
- regional planning (1)
- reinforcement (1)
- rural (1)
- school of architecture (1)
- scientific visualization, virtual environments, Big Data, radio astronomy (1)
- social housing (1)
- social network analysis (1)
- space (1)
- space allocation (1)
- space management (1)
- space management model (1)
- space optimization (1)
- stochastic (1)
- structure (1)
- symbolische Bildwelt (1)
- symmetric crypto (1)
- territorial policies (1)
- the bottom-up approach to urban planning (1)
- timber structure (1)
- town planning (1)
- transition (1)
- tuned mass damper (1)
- university (1)
- urban agriculture (1)
- urban beekeeping (1)
- urban design (1)
- urban history, urban design, fascist period, sport city, Rome, Enrico Del Debbio (1)
- urban sociology (1)
- urban studies (1)
- westliche Kultur (1)
- wind (1)
- Étienne de Groër (1)
- Ökobilanz (1)
- Überhitzung (1)
Year of publication
- 2015 (125) (remove)
What is nowadays called (classic) Clifford analysis consists in the establishment of a function theory for functions belonging to the kernel of the Dirac operator. While such functions can very well describe problems of a particle with internal SU(2)-symmetries, higher order symmetries are beyond this theory. Although many modifications (such as Yang-Mills theory) were suggested over the years they could not address the principal problem, the need of a n-fold factorization of the d’Alembert operator. In this paper we present the basic tools of a fractional function theory in higher dimensions, for the transport operator (alpha = 1/2 ), by means of a fractional correspondence to the Weyl relations via fractional Riemann-Liouville derivatives. A Fischer decomposition, fractional Euler and Gamma operators, monogenic projection, and basic fractional homogeneous powers are constructed.
The stress state of a piecewise-homogeneous elastic body, which has a semi-infinite crack along the interface, under in-plane and antiplane loads is considered. One of the crack edges is reinforced by a rigid patch plate on a finite interval adjacent to the crack tip. The crack edges are loaded with specified stresses. The body is stretched at infinity by specified stresses. External forces with a given principal vector and moment act on the patch plate. The problem reduces to a Riemann-Hilbert boundary-value matrix problem with a piecewise-constant coefficient for two complex potentials in the plane case and for one in the antiplane case. The complex potentials are found explicitly using a Gaussian hypergeometric function. The stress state of the body close to the ends of the patch plate, one of which is also simultaneously the crack tip, is investigated. Stress intensity factors near the singular points are determined.
In this paper we introduce LUCI, a Lightweight Urban Calculation Interchange system, designed to bring the advantages of a calculation and content co-ordination system to small planning and design groups by the means of an open source middle-ware. The middle-ware focuses on problems typical to urban planning and therefore features a geo-data repository as well as a job runtime administration, to coordinate simulation models and its multiple views. The described system architecture is accompanied by two exemplary use cases that have been used to test and further develop our concepts and implementations.
In this paper we introduce LUCI, a Lightweight Urban Calculation Interchange system, designed to bring the advantages of a calculation and content co-ordination system to small planning and design groups by the means of an open source middle-ware. The middle-ware focuses on problems typical to urban planning and therefore features a geo-data repository as well as a job runtime administration, to coordinate simulation models and its multiple views. The described system architecture is accompanied by two exemplary use cases that have been used to test and further develop our concepts and implementations.
From the design experiences of arch dams in the past, it has significant practical value to carry out the shape optimization of arch dams, which can fully make use of material characteristics and reduce the cost of constructions. Suitable variables need to be chosen to formulate the objective function, e.g. to minimize the total volume of the arch dam. Additionally a series of constraints are derived and a reasonable and convenient penalty function has been formed, which can easily enforce the characteristics of constraints and optimal design. For the optimization method, a Genetic Algorithm is adopted to perform a global search. Simultaneously, ANSYS is used to do the mechanical analysis under the coupling of thermal and hydraulic loads. One of the constraints of the newly designed dam is to fulfill requirements on the structural safety. Therefore, a reliability analysis is applied to offer a good decision supporting for matters concerning predictions of both safety and service life of the arch dam. By this, the key factors which would influence the stability and safety of arch dam significantly can be acquired, and supply a good way to take preventive measures to prolong ate the service life of an arch dam and enhances the safety of structure.
Communities in discourse and space. Towards a spatial dialectic in gated residential developments
(2015)
This research projects deals with the discoursivity of spatial production.
By looking at contemporary residential development in the city of Istanbul, I will examine the reciprocity of the material production of space on one hand, and social discourses on the other, in order to make a contribution to how physical space can be used as a source of research in urban studies. In real estate marketing social discourses are used as a source of reference for place branding or identity design. Branding concepts therefore relate to how social groups imagine their position or future position in society, imaginaries that are continuously influenced and changed by social dynamics within the city but also from the outside. How such urban identities are formed and it what way they relate to the urban environment is crucial to a wide spectrum of social and cultural science. The constitutive role urban space attains has been described and analysed in much detail. Such scrutiny however has yet to be applied to the visual and communicative forms of engagement, the build environment partakes in the formation and change of social discourses.
The sizing of simple resonators like guitar strings or laser mirrors is directly connected to the wavelength and represents no complex optimisation problem. This is not the case with liquid-filled acoustic resonators of non-trivial geometries, where several masses and stiffnesses of the structure and the fluid have to fit together. This creates a scenario of many competing and interacting resonances varying in relative strength and frequency when design parameters change. Hence, the resonator design involves a parameter-tuning problem with many local optima. As its solution evolutionary algorithms (EA) coupled to a forced-harmonic FE simulation are presented. A new hybrid EA is proposed and compared to two state-of-theart EAs based on selected test problems. The motivating background is the search for better resonators suitable for sonofusion experiments where extreme states of matter are sought in collapsing cavitation bubbles.
Superplasticizers are utilized both to improve the fluidity during the placement and to reduce the water content of concretes. Both effects have also an impact on the properties of the hardened concrete. As a side effect the presence of superplasticizers affects the strength development of concretes that is strongly retarded. This may lead to an ecomomical drawback of the concrete manufacturing. The present work is aimed at gaining insights on the causes of the retarding effect of superplasticizers on the hydration of Portland cement. In order to simplify the complex interactions occurring during the hydration of Portland cement the majority of the work focuses on the interaction of superplasticizer and tricalcium silicate (Ca3SiO5 or C3S, the main compound of Portland cement clinker). The tests are performed in three main parts accompanied by methods as for example isothermal conduction calorimetry, electrical conductivity, Electron Microscopy, ICP-OES, TOC, as well as Analytical Ultracentrifugation.
In the first main part and based on the interaction of cations and anionic charges of polymers, the interactions between calcium ions and superplasticizers are investigated. As a main effect calcium ions are complexed by the functional groups of the polymers (carboxy, sulfonic). Calcium ions may be both dissolved in the aqueous phase and a constitute of particle interfaces. Besides these effects it is furthermore shown that superplasticizers induce the formation of nanoscaled particles which are dispersed in the aqueous phase (cluster formation). Analogous to recent findings in the field of biomineralization, it is reasonable to assume that these nanoparticles influence the crystal growth by their assembly process.
Based on the assumption that superplasticizers hinder either or both dissolution and precipitation and by that retard the cement hydration, the impact on separate reactions is investigated. On experiments that address the solubility of C-S-H phases and portlandite, it is shown that complexation of calcium ions in the aqueous phase by functional groups of polymers increases the solubility of portlandite. Contrary, in case of C-S-H solubility the complexation of calcium ions in solution leads to decrease of the calcium ion concentration in the aqueous phase. These effects are explained by differences in adsorption of polymers on C-S-H phases and portlandite. It is proposed that adsorption is stronger on C-S-H phases compared to portlandite due to the increased specific surface area of C-S-H phases. Following that, it is claimed that before polymers are able to adsorb on C-S-H phases the functional groups must be screened by calcium ions in the aqueous phase. It is further shown that data regarding the impact of superplasticizers on the unconstrained dissolution rate of C3S does not provide a clear relation to the overall retarding effect occurring during the hydration of C3S. Both increased and decreased dissolution rate with respect to the reference sample are detected. If the complexation capability of the superplasticizers is considered then also a reduced dissolution rate of C3S is determined. Despite the fact that the global hydration process is accelerated, the addition of calcite leads to a slower dissolution rate. Thus, a hindered unconstrained dissolution of C3S as possibly cause for the retarding effect still remains open for discussion. In the last section of this part, the pure crystallization of hydrate phases (C-S-H phases, portlandite) is fathomed. Results clearly show that superplasticizers prolong the induction time and modify the rate of crystal growth during pure crystallization in particular due to the complexation of ions in solution. But this effect is insufficient to account for the overall retarding effect. Further important factors are the blocking of crystal growth faces by adsorbed polymers and the dispersion of nanoscaled particles which hinders their agglomeration in order to build up crystals.
In the last main part of the work, the previously gathered results are utilized in order to investigate hydration kinetics. During hydration, dissolution and precipitation occur in parallel. Thereby, special attention is laid on the ion composition of the aqueous phase of C3S pastes and suspensions in order to determine the rate limiting step. All in all it is concluded that the retarding effect of superplasticizers on the hydration of tricalcium silicate is based on the retardation of crystallization of hydrate phases (C-S-H phases and portlandite). Thereby, the two effects complexation of calcium ions on surfaces and stabilization of nanoscaled particles are of major importance. These mechanisms may partly be compensated by template performance and increase in solubility by complexation of ions in solution. The decreased dissolution rate of C3S by the presence of superplasticizers during the in parallel occuring hydration process can only be assessed indirectly by means of the development of the ion concentrations in the aqueous phase (reaction path). Whether this observation is the cause or the consequence within the dissolution-precipitation process and therefore accounts for the retarding effect remains a topic for further investigations.
Besides these results it is shown that superplasticizers can be associated chemically with inhibitors because they reduce the frequency factor to end the induction period. Because the activation energy is widely unaffected it is shown that the basic reaction mechanism sustain. Furthermore, a method was developed which permits for the first time the determination of ion concentrations in the aqueous phase of C3S pastes in-situ. It is shown that during the C3S hydration the ion concentration in the aqueous phase is developed correspondingly to the heat release rate (calorimetry). The method permits the differentiation of the acceleration period in three stages. It is emphasized that crystallization of the product phases of C3S hydration, namely C-S-H phases and portlandite, are responsible for the end of the induction period.