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Building Structure (building + structure)
Selected AbstractsIdentification of Modal Combinations for Nonlinear Static Analysis of Building StructuresCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2004Sashi K. Kunnath An increasingly popular analytical method to establish these demand values is a "pushover" analysis in which a model of the building structure is subjected to an invariant distribution of lateral forces. Although such an approach takes into consideration the redistribution of forces following yielding of sections, it does not incorporate the effects of varying dynamic characteristics during the inelastic response. Simple modal combination schemes are investigated in this article to indirectly account for higher mode effects. Because the modes that contribute to deformations may be different from the modes that contribute to forces, it is necessary to identify unique modal combinations that provide reliable estimates of both force and deformation demands. The proposed procedure is applied to typical moment frame buildings to assess the effectiveness of the methodology. It is shown that the envelope of demands obtained from a series of nonlinear static analysis using the proposed modal-combination-based lateral load patterns results in better estimation of inter-story drift, a critical parameter in seismic evaluation and design. [source] Nonparametric Identification of a Building Structure from Experimental Data Using Wavelet Neural NetworkCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2003Shih-Lin Hung By combining wavelet decomposition and artificial neural networks (ANN), wavelet neural networks (WNN) are used for solving chaotic signal processing. The basic operations and training method of wavelet neural networks are briefly introduced, since these networks can approximate universal functions. The feasibility of structural behavior modeling and the possibility of structural health monitoring using wavelet neural networks are investigated. The practical application of a wavelet neural network to the structural dynamic modeling of a building frame in shaking tests is considered in an example. Structural acceleration responses under various levels of the strength of the Kobe earthquake were used to train and then test the WNNs. The results reveal that the WNNs not only identify the structural dynamic model, but also can be applied to monitor the health condition of a building structure under strong external excitation. [source] Simplified seismic analysis of asymmetric building systemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2007Jui-Liang Lin Abstract The paper reviews the uncoupled modal response history analysis (UMRHA) and modal pushover analysis (MPA) procedure in the analysis of asymmetric structures. From the pushover curves in ADRS format, showing the relationships of base shear versus roof translation and base torque versus roof rotation, a bifurcating characteristic of the pushover curves of an asymmetric structure is observed. A two-degree-of-freedom (2DOF) modal stick is constructed using lump mass eccentrically placed at the end of beam which is connected with the column by a rotational spring. By converting the equation of motion of a whole structure into 2DOF modal equations, all of the elastic properties in the 2DOF modal sticks can be determined accurately. A mathematical proof is carried out to demonstrate that the 2DOF modal stick is consistent with the single-degree-of-freedom (SDOF) modal stick at elastic state. The bifurcating characteristic of modal pushover curves and the interaction of modal translation and rotation can be considered rationally by this 2DOF modal stick. In order to verify the effectiveness of this proposed 2DOF modal stick, a two-storey asymmetric building structure was analysed by the UMRHA procedure incorporating this novel 2DOF modal sticks (2DMPA) and conventional SDOF modal sticks (SDMPA), respectively. The analytical results are compared with those obtained by nonlinear response history analysis (RHA). It is illustrated that the accuracy of the rotational response histories obtained by 2DMPA is much better than those obtained by SDMPA. Consequently, the estimations of translational response histories on flexible side (FS) and stiff side (SS) of the building structure are also improved. Copyright © 2006 John Wiley & Sons, Ltd. [source] Geothermal energy systems for major projects , design and construction / . Geothermieanlagen bei Großprojekten , Planung und UmsetzungGEOMECHANICS AND TUNNELLING, Issue 5 2010Dipl.-Ing. Geothermal energy - Geothermie Abstract The application of geothermal energy has increased in the last couple of years in order to provide the heating or cooling demands of major projects. Open systems using groundwater directly can be used for geothermal energy extraction as well as closed systems with absorber pipes installed in underground structures. An accurate design, which considers the requirements of the energy consumer in particular but also the subsoiland groundwater conditions, the foundation concept and the building structure, as well as project-specific technical, legal and economic conditions, is required for economically efficient application. Diligent supervision is necessary during the construction stage to avoid any damage to absorber pipes, which could result in loss of performance. Zur Deckung des Heiz- oder Kühlbedarfs bei Großprojekten wird in den letzten Jahren vermehrt auf eine Erdwärmenutzung gesetzt. Dabei kommen sowohl offene Systeme wie eine direkte Grundwassernutzung als auch geschlossene Systeme mit Absorberleitungen in erdberührten Bauteilen zur Anwendung. Für eine wirtschaftliche Umsetzung bedarf es zunächst einer sorgfältigen Planung, wobei insbesondere die Anforderungen des Nutzers, die Untergrund- und Grundwasserverhältnisse, das Gründungskonzept einschließlich der Gebäudestruktur sowie projektspezifische technische, rechtliche und wirtschaftliche Randbedingungen zu berücksichtigen sind. In der Bauphase ist für eine plangemäße Umsetzung mit besonderer Sorgfalt vorzugehen, um Beschädigungen der Absorberleitungen und somit Leistungsminderungen zu vermeiden. [source] Low home ventilation rate in combination with moldy odor from the building structure increase the risk for allergic symptoms in childrenINDOOR AIR, Issue 3 2009L. Hägerhed-Engman First page of article [source] ANALYSIS OF ROMAN WALL PAINTINGS FROM THE THERMAE OF ,IULIA CONCORDIA'ARCHAEOMETRY, Issue 4 2010G. A. MAZZOCCHIN Twenty-six wall painting fragments and some plaster, ,intonachino' and stucco samples, discovered at Iulia Concordia, have been studied by different analytical techniques to gain information about the pigment nature and the composition of the materials. The presence of calcite, dolomite and aragonite allow the distinction of four groups of wall samples varying in the nature of pigments and in the application technique. These differences can be attributed to different execution times or, more probably, to the arrangement of the rooms in the building structure. The nature of the pigments found in the Thermae of Iulia Concordia appears similar to that found in other Roman villas of Venetia et Histria, with the use of precious pigments such as Egyptian blue and cinnabar. [source] Einwirkungen nach DIN-Fachbericht 101BETON- UND STAHLBETONBAU, Issue 8 2004Lothar Weinreich Dipl.-Ing. Nach der Einführung der DIN-Fachberichte sind alle Bauwerksentwürfe nach dem neuen Regelwerk zu bearbeiten. Der Beitrag beschreibt, in welchen wesentlichen Punkten sich Änderungen bei der Entwurfsbearbeitung gegenüber dem bisherigen Vorgehen ergeben. Für die Vorberechnung von Massivbrücken in Längsrichtung werden die maßgebenden Einwirkungen nach altem und neuem Vorschriftenwerk gegenübergestellt. Es wird außerdem gezeigt, daß die Neuerungen bei den anzusetzenden Einwirkungen in einigen Fällen Änderungen bei den bislang gewählten Bauwerkssystemen und -abmessungen erforderlich machen. Die gegenüber einer Bearbeitung nach DIN-Normen besonders zu beachtenden Punkte werden zusammengestellt. Actions according to DIN-Fachbericht 101: Effects on the Design of Concrete Road Bridges After the introduction of the DIN-Fachberichte all concept designs have to follow the new code of practice. This article describes in which the essential points there are modifications in the concept design compared to the previous actions. For the precalculation of concrete bridges for longitudinal direction the essential actions according to old and new code of practice are compared. It is shown that the innovations of the calculated actions in some cases can make changes in the building structure and the dimension necessary as well. [source] Dynamic Wavelet Neural Network for Nonlinear Identification of Highrise BuildingsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2005Xiaomo Jiang Compared with conventional neural networks, training of a dynamic neural network for system identification of large-scale structures is substantially more complicated and time consuming because both input and output of the network are not single valued but involve thousands of time steps. In this article, an adaptive Levenberg,Marquardt least-squares algorithm with a backtracking inexact linear search scheme is presented for training of the dynamic fuzzy WNN model. The approach avoids the second-order differentiation required in the Gauss,Newton algorithm and overcomes the numerical instabilities encountered in the steepest descent algorithm with improved learning convergence rate and high computational efficiency. The model is applied to two highrise moment-resisting building structures, taking into account their geometric nonlinearities. Validation results demonstrate that the new methodology provides an efficient and accurate tool for nonlinear system identification of high-rising buildings. [source] Advanced Analysis of Steel Frames Using Parallel Processing and VectorizationCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2001C. M. Foley Advanced methods of analysis have shown promise in providing economical building structures through accurate evaluation of inelastic structural response. One method of advanced analysis is the plastic zone (distributed plasticity) method. Plastic zone analysis often has been deemed impractical due to computational expense. The purpose of this article is to illustrate applications of plastic zone analysis on large steel frames using advanced computational methods. To this end, a plastic zone analysis algorithm capable of using parallel processing and vector computation is discussed. Applicable measures for evaluating program speedup and efficiency on a Cray Y-MP C90 multiprocessor supercomputer are described. Program performance (speedup and efficiency) for parallel and vector processing is evaluated. Nonlinear response including postcritical branches of three large-scale fully restrained and partially restrained steel frameworks is computed using the proposed method. The results of the study indicate that advanced analysis of practical steel frames can be accomplished using plastic zone analysis methods and alternate computational strategies. [source] Current situation of German care homesINTERNATIONAL JOURNAL OF OLDER PEOPLE NURSING, Issue 4 2008Barbara Klein Dipl-Soz, Dr. Phil Aim., The aim of this paper is to explore the situation of and current developments in the German care home sector. Background., Germany, like other Western countries, faces demographic change and subsequently tries to develop structures and processes to achieve a care system which can tackle the increasing number of people in need of care with a variety of quality services. Policy strives to set up structures and instruments to enhance the quality of service provision. Discussion., Figures show that the structures in the care sector are changing in favour to increased privatization of homes, a slight increase in size and improved building structures. In order to tackle the expected changes, a mix of low and high skilled qualification and new job profiles arise in the care sector. Other changes to be observed are the development of new living arrangements and the utilization of new technologies to support the care process. Conclusion., This contribution looks at the socio-demographic changes in care, the statutory developments and the structures of care homes as well as current discussions on future developments. [source] Environmental Impacts of Products: A Detailed Review of StudiesJOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2006Arnold Tukker Summary Environmental effects of economic activities are ultimately driven by consumption, via impacts of the production, use, and waste management phases of products and services ultimately consumed. Integrated product policy (IPP) addressing the life-cycle impacts of products forms an innovative new generation of environmental policy. Yet this policy requires insight into the final consumption expenditures and related products that have the greatest life-cycle environmental impacts. This review article brings together the conclusions of 11 studies that analyze the life-cycle impacts of total societal consumption and the relative importance of different final consumption categories. This review addresses in general studies that were included in the project Environmental Impacts of Products (EIPRO) of the European Union (EU), which form the basis of this special issue. Unlike most studies done in the past 25 years on similar topics, the studies reviewed here covered a broad set of environmental impacts beyond just energy use or carbon dioxide (CO2) emissions. The studies differed greatly in basic approach (extrapolating LCA data to impacts of consumption categories versus approaches based on environmentally extended input-output (EEIO) tables), geographical region, disaggregation of final demand, data inventory used, and method of impact assessment. Nevertheless, across all studies a limited number of priorities emerged. The three main priorities, housing, transport, and food, are responsible for 70% of the environmental impacts in most categories, although covering only 55% of the final expenditure in the 25 countries that currently make up the EU. At a more detailed level, priorities are car and most probably air travel within transport, meat and dairy within food, and building structures, heating, and (electrical) energy-using products within housing. Expenditures on clothing, communication, health care, and education are considerably less important. Given the very different approaches followed in each of the sources reviewed, this result hence must be regarded as extremely robust. Recommendations are given to harmonize and improve the methodological approaches of such analyses, for instance, with regard to modeling of imports, inclusion of capital goods, and making an explicit distinction between household and government expenditure. [source] Virtuelles Bauen und partnerschaftliche Geschäftsmodelle , eine innovative VerbindungBAUTECHNIK, Issue 7 2006Mike Gralla Univ.-Prof. Durch eine frühe Zusammenarbeit von Bauherrn, Planern und Bauunternehmen können mit partnerschaftlichen Geschäftsmodellen wesentliche Nachteile von herkömmlichen Geschäftsbeziehungen im Bauwesen aufgelöst werden. Die enge Zusammenarbeit in einer frühen Phase eines Bauvorhabens ermöglicht eine fachübergreifende Optimierung hinsichtlich Planung, Bauausführung und Nutzung einer Immobilie. Hierbei sind die Methoden des virtuellen Bauens zweckmäßige Hilfsmittel, um die Koordination des Projekts und die Kommunikation zwischen den an einem Bauvorhaben beteiligten Partnern zu verbessern. Deshalb hat sich insbesondere bei partnerschaftlichen Geschäftsmodellen, die eine Preconstruction-Phase enthalten, die Verwendung von virtuellem Bauen als besonders wirksam erwiesen. Virtuelles Bauen unterstützt die Optimierung eines Bauwerks und hilft bei der anschaulichen Kommunikation von Optimierungsergebnissen durch die Visualisierung mit interaktiven Computermodellen. Virtual Design and Construction (ViCon) führt das virtuelle Bauen in die tägliche Planungs- und Baupraxis ein und ist eine Schlüsseltechnologie des Bauwesens. ViCon wird in der Praxis bei zahlreichen Projekten eingesetzt, die mit dem partnerschaftlichen Geschäftsmodell PreFair durchgeführt werden. In diesem Beitrag werden die Einsatzmöglichkeiten von ViCon an ausgewählten Beispielen dargestellt. Virtual construction and partnership-based business models , an innovative combination. When clients, design engineers and construction companies work together within the framework of partnership-based business models from an early stage, major disadvantages of traditional business relationships in the construction sector can be eliminated. Close cooperation in an early phase of a construction project makes for interdisciplinary optimization with regard to a property's design, construction and utilization. In this context, the methods of virtual construction are useful tools to improve communication between the parties involved in a construction project. Using virtual construction has therefore proved to be particularly effective when working with partnership-based business models that comprise a preconstruction phase. Virtual construction helps to optimize building structures and assists in graphically communicating optimization results by way of visualization with interactive computer models. Virtual Design and Construction (ViCon) introduces virtual construction in the daily design and construction work and is a key technology in the construction industry. In practice, ViCon is employed in numerous projects that are implemented based on the PreFair business model. Using selected examples, this article shows the range of ViCon's possible application. [source] Zur sinnvollen Anwendung ganzheitlicher Gebäudemodelle in der Tragwerksplanung von Hochbauten,BETON- UND STAHLBETONBAU, Issue 10 2009Michael Fastabend Prof. Dr.-Ing. Entwurf und Konstruktion Abstract Ausgehend von den kritischen Randbedingungen der Berechnung mit ganzheitlichen Gebäudemodellen werden typische und häufig anzutreffende Konstruktionsfälle diskutiert, bei denen Gesamtmodelle Vorteile für den Entwurf aufzeigen. Hier sind räumliche Tragwirkungen zu nennen, die Erfassung von Zwangsbeanspruchungen bei komplexen Grundrissen mit vielfältigen Festhaltungen sowie die Beanspruchung schlanker Gebäudestrukturen aus Windlasten und seismischen Einwirkungen. Für die genannten sinnvollen Anwendungsfälle werden die notwendigen Randbedingungen diskutiert. Die jeweiligen Anwendungsfälle werden anhand konkreter Gebäudebeispiele vorgestellt. On the reasonable use of total building models in the design of building structures Coming from the critical boundary conditions of the calculation with total building models, typical and prevalent constructions, where total models show advantages for the design, will be discussed. Here, spatial load-bearing impact, the registration of unforced interactions of complex ground plans with various supports as well as the stressing of slender building structures resulting from wind loads and seismic impacts have to be mentioned. For the stated reasonable use cases the necessary boundary conditions will be discussed. The respective use cases will be presented by means of concrete building examples. [source] | ||||||||||||||||||||||