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DIN
Kinds of DIN Terms modified by DIN Selected AbstractsDas allgemeine bauaufsichtliche Prüfzeugnis als Verwendbarkeits- und Anwendbarkeitsnachweis hinsichtlich der Anforderungen an den SchallschutzDIBT MITTEILUNGEN (FORMERLY-MITTEILUNGEN DEUT INST FUER BAUTECHNIK), Issue 3 2006Frank Iffländer Dipl.-Ing. Wenn für Bauteile Anforderungen an den Schallschutz nach DIN 4109 bestehen, ist der Nachweis der Eignung gemäß Abschnitt 6.3 der Norm mit bauakustischen Messungen (Eignungsprüfungen) zu führen, wenn die Bauteile nicht den Ausführungsbeispielen nach Beiblatt 1 zu DIN 4109 entsprechen. In der Liste der Technischen Baubestimmungen ist festgelegt, dass diese in DIN 4109 geforderten Eignungsprüfungen im Rahmen der Erteilung eines allgemeinen bauaufsichtlichen Prüfzeugnisses durchzuführen sind. Für eine Vielzahl von Bauprodukten und Bauarten, die Anforderungen an den Schallschutz zu erfüllen haben, kommt daher dem allgemeinen bauaufsichtlichen Prüfzeugnis eine besondere Bedeutung zu. [source] Zum Stand der Einführung der Normenreihe EN 1337 sowie deren Auswirkung auf die allgemeinen bauaufsichtlichen Zulassungen und Prüfzeugnisse und die Normenreihe DIN 4141DIBT MITTEILUNGEN (FORMERLY-MITTEILUNGEN DEUT INST FUER BAUTECHNIK), Issue 3 2005Heinrich Buche Dipl.-Ing. First page of article [source] Verzeichnis der Holzbaubetriebe, die den Nachweis der Eignung zum Leimen von tragenden Holzbauteilen nach DIN 1052,1 erbracht habenDIBT MITTEILUNGEN (FORMERLY-MITTEILUNGEN DEUT INST FUER BAUTECHNIK), Issue 4 2004Article first published online: 5 AUG 200 [source] Verzeichnis der Holzbaubetriebe, die den Nachweis der Eignung zum Leimen von tragenden Holzbauteilen nach DIN 1052-1 erbracht habenDIBT MITTEILUNGEN (FORMERLY-MITTEILUNGEN DEUT INST FUER BAUTECHNIK), Issue 2 2004Article first published online: 27 MAY 200 [source] Precipitation control over inorganic nitrogen import,export budgets across watersheds: a synthesis of long-term ecological researchECOHYDROLOGY, Issue 2 2008E. S. Kane Abstract We investigated long-term and seasonal patterns of N imports and exports, as well as patterns following climate perturbations, across biomes using data from 15 watersheds from nine Long-Term Ecological Research (LTER) sites in North America. Mean dissolved inorganic nitrogen (DIN) import,export budgets (N import via precipitation,N export via stream flow) for common years across all watersheds was highly variable, ranging from a net loss of , 0·17 ± 0·09 kg N ha,1mo,1 to net retention of 0·68 ± 0·08 kg N ha,1mo,1. The net retention of DIN decreased (smaller import,export budget) with increasing precipitation, as well as with increasing variation in precipitation during the winter, spring, and fall. Averaged across all seasons, net DIN retention decreased as the coefficient of variation (CV) in precipitation increased across all sites (r2 = 0·48, p = 0·005). This trend was made stronger when the disturbed watersheds were withheld from the analysis (r2 = 0·80, p < 0·001, n = 11). Thus, DIN exports were either similar to or exceeded imports in the tropical, boreal, and wet coniferous watersheds, whereas imports exceeded exports in temperate deciduous watersheds. In general, forest harvesting, hurricanes, or floods corresponded with periods of increased DIN exports relative to imports. Periods when water throughput within a watershed was likely to be lower (i.e. low snow pack or El Niño years) corresponded with decreased DIN exports relative to imports. These data provide a basis for ranking diverse sites in terms of their ability to retain DIN in the context of changing precipitation regimes likely to occur in the future. Copyright © 2008 John Wiley & Sons, Ltd. [source] The effect of land use on dissolved organic carbon and nitrogen uptake in streamsFRESHWATER BIOLOGY, Issue 11 2009LAURA T. JOHNSON Summary 1. Agricultural and urban land use may increase dissolved inorganic nitrogen (DIN) concentrations in streams and saturate biotic nutrient demand, but less is known about their impacts on the cycling of organic nutrients. To assess these impacts we compared the uptake of DIN (as ammonium, NH4+), dissolved organic carbon (DOC, as acetate), and dissolved organic nitrogen (DON, as glycine) in 18 low-gradient headwater streams in southwest Michigan draining forested, agricultural, or urban land-use types. Over 3 years, we quantified uptake in two streams in each of the three land-use types during three seasons (spring, summer and autumn). 2. We found significantly higher NH4+ demand (expressed as uptake velocity, Vf) in urban compared to forested streams and NH4+Vf was greater in spring compared to summer and autumn. Acetate Vf was significantly higher than NH4+ and glycine Vf, but neither acetate nor glycine Vf were influenced by land-use type or season. 3. We examined the interaction between NH4+ and acetate demand by comparing simultaneous short-term releases of both solutes to releases of each solute individually. Acetate Vf did not change during the simultaneous release with NH4+, but NH4+Vf was significantly higher with increased acetate. Thus, labile DOC Vf was not limited by the availability of NH4+, but NH4+Vf was limited by the availability of labile DOC. In contrast, neither glycine nor NH4+Vf changed when released simultaneously indicating either that overall N-uptake was saturated or that glycine and NH4+ uptake were controlled by different factors. 4. Our results suggest that labile DOC and DON uptake can be equivalent to, or even higher than NH4+ uptake, a solute known to be highly bioreactive, but unlike NH4+ uptake, may not differ among land-use types and seasons. Moreover, downstream export of nitrogen may be exacerbated by limitation of NH4+ uptake by the availability of labile DOC in headwater streams from the agricultural Midwestern United States. Further research is needed to identify the factors that influence cycling of DOC and DON in streams. [source] Time-dependent heat transfer coefficient of a wallINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2003Periklis E. Ergatis Abstract A time-dependent coefficient of heat transfer is proposed for the computation of thermal power required, so that a room temperature reaches a desired value within a given time. A mathematical formulation of the room heating transient phenomenon is constructed in a dimensionless form. Using an integral approximate solution an analytical expression for this coefficient is provided and it is verified by diagrams adopted by DIN 4701. Copyright © 2003 John Wiley & Sons, Ltd. [source] From dynamic influence nets to dynamic Bayesian networks: A transformation algorithmINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2009Sajjad Haider This paper presents an algorithm to transform a dynamic influence net (DIN) into a dynamic Bayesian network (DBN). The transformation aims to bring the best of both probabilistic reasoning paradigms. The advantages of DINs lie in their ability to represent causal and time-varying information in a compact and easy-to-understand manner. They facilitate a system modeler in connecting a set of desired effects and a set of actionable events through a series of dynamically changing cause and effect relationships. The resultant probabilistic model is then used to analyze different courses of action in terms of their effectiveness to achieve the desired effect(s). The major drawback of DINs is their inability to incorporate evidence that arrive during the execution of a course of action (COA). Several belief-updating algorithms, on the other hand, have been developed for DBNs that enable a system modeler to insert evidence in dynamic probabilistic models. Dynamic Bayesian networks, however, suffer from the intractability of knowledge acquisition. The presented transformation algorithm combines the advantages of both DINs and DBNs. It enables a system analyst to capture a complex situation using a DIN and pick the best (or close-to-best) COA that maximizes the likelihood of achieving the desired effect. During the execution, if evidence becomes available, the DIN is converted into an equivalent DBN and beliefs of other nodes in the network are updated. If required, the selected COA can be revised on the basis of the recently received evidence. The presented methodology is applicable in domains requiring strategic level decision making in highly complex situations, such as war games, real-time strategy video games, and business simulation games. © 2009 Wiley Periodicals, Inc. [source] Temporal Coherence of Chlorophyll a during a Spring Phytoplankton Bloom in Xiangxi Bay of Three-Gorges Reservoir, ChinaINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 6 2009Yao-Yang Xu Abstract Algal bloom phenomenon was defined as "the rapid growth of one or more phytoplankton species which leads to a rapid increase in the biomass of phytoplankton", yet most estimates of temporal coherence are based on yearly or monthly sampling frequencies and little is known of how synchrony varies among phytoplankton or of the causes of temporal coherence during spring algal bloom. In this study, data of chlorophyll a and related environmental parameters were weekly gathered at 15 sampling sites in Xiangxi Bay of Three-Gorges Reservoir (TGR, China) to evaluate patterns of temporal coherence for phytoplankton during spring bloom and test if spatial heterogeneity of nutrient and inorganic suspended particles within a single ecosystem influences synchrony of spring phytoplankton dynamics. There is a clear spatial and temporal variation in chlorophyll a across Xiangxi Bay. The degree of temporal coherence for chlorophyll a between pairs of sites located in Xiangxi Bay ranged from ,0.367 to 0.952 with mean and median values of 0.349 and 0.321, respectively. Low levels of temporal coherence were often detected among the three stretches of the bay (Down reach, middle reach and upper reach), while high levels of temporal coherence were often found within the same reach of the bay. The relative difference of DIN between pair sites was the strong predictor of temporal coherence for chlorophyll a in down and middle reach of the bay, while the relative difference in Anorganic Suspended Solids was the important factor regulating temporal coherence in middle and upper reach. Contrary to many studies, these results illustrate that, in a small geographic area (a single reservoir bay of approximately 25 km), spatial heterogeneity influence synchrony of phytoplankton dynamics during spring bloom and local processes may override the effects of regional processes or dispersal. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Variability of Organic Matter Processing in a Mediterranean Coastal LagoonINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 5-6 2004Margarita Menéndez Abstract The spatial variability of plant organic matter processing was studied experimentally in a shallow coastal lagoon (Tancada lagoon, average depth: 37 cm, area: 1.8 km2) in the Ebro River Delta (NE Spain). To determine the effect of hydrology and sediment characteristics on plant organic matter processing, leaves of Phragmites australis at the end of its vegetative cycle and whole plants of Ruppia cirrhosa(Petagna) Grande, just abscised, were enclosed in litter bags. Two different mesh sizes (100 ,m and 2 mm) were used to study the effect of macroinvertebrates on decomposition. The bags were placed in the water column and approximately 15 cm above the sediment at 6 different locations in the lagoon. The experiment was performed twice, in autumn-winter and spring-summer. The effect of macroinvertebrates on decomposition rate was not significant in Tancada lagoon. Breakdown rates showed spatial differences only in spring-summer. In the autumn-winter experiment, the effect of strong wind masked the effects of environmental variables and hydrology on decomposition rate. In the spring-summer experiment, characterised by high stability of the water column, dissolved inorganic nitrogen (DIN) concentration in the water column and organic matter in the sediment were the main factors determining the variability of organic matter processing. A positive relationship was calculated between P. australis decomposition rate and dissolved inorganic nitrogen in spring-summer (r2 = 0.92, p < 0.001). (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Concepts and semantic relations in information scienceJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 10 2010Wolfgang G. Stock Concept-based information retrieval and knowledge representation are in need of a theory of concepts and semantic relations. Guidelines for the construction and maintenance of knowledge organization systems (KOS) (such as ANSI/NISO Z39.19-2005 in the U.S.A. or DIN 2331:1980 in Germany) do not consider results of concept theory and theory of relations to the full extent. They are not able to unify the currently different worlds of traditional controlled vocabularies, of the social web (tagging and folksonomies) and of the semantic web (ontologies). Concept definitions as well as semantic relations are based on epistemological theories (empiricism, rationalism, hermeneutics, pragmatism, and critical theory). A concept is determined via its intension and extension as well as by definition. We will meet the problem of vagueness by introducing prototypes. Some important definitions are concept explanations (after Aristotle) and the definition of family resemblances (in the sense of Wittgenstein). We will model concepts as frames (according to Barsalou). The most important paradigmatic relation in KOS is hierarchy, which must be arranged into different classes: Hyponymy consists of taxonomy and simple hyponymy, meronymy consists of many different part-whole-relations. For practical application purposes, the transitivity of the given relation is very important. Unspecific associative relations are of little help to our focused applications and should be replaced by generalizable and domain-specific relations. We will discuss the reflexivity, symmetry, and transitivity of paradigmatic relations as well as the appearance of specific semantic relations in the different kinds of KOS (folksonomies, nomenclatures, classification systems, thesauri, and ontologies). Finally, we will pick out KOS as a central theme of the Semantic Web. [source] Capacity of selected ionic liquids as alternative EP/AW additiveLUBRICATION SCIENCE, Issue 6-7 2010Ameneh Schneider Abstract In this paper, it is shown that specific ionic liquids have great potential to be used as additives for tribological applications. The results promise a high load carrying capacity; especially for the cation 3-Octhylthiazolium and long term stability up to temperatures of 120°C is given. However, only extreme pressures/anti-wear properties are examined in detail with the selected test method. Friction modifier (FM) effectiveness cannot easily be demonstrated, because of the good performance of the selected base stock. Nevertheless, ionic liquids in general did not change the FM characteristic of the base oil in a negative way. A promising potential for ionic liquids to replace a majority of additives in tribological systems is given. Methods used are Schwing-Reib-Verschleiß test according to DIN ASTM D 5706, and Four Ball Tests according to DIN 51360. Mechanisms related to additives in lubricants are investigated by X-ray photoelectron spectroscopy. Copyright © 2010 John Wiley & Sons, Ltd. [source] DSC as a valuable tool for the grease laboratoryLUBRICATION SCIENCE, Issue 3 2000Martin Josef Pohlen Abstract There is a need to reduce both the time and cost involved in research and development for lubricating greases. Most of the normal test methods used to characterise a grease are long-term tests, but it is important to develop screening tests that also give reliable information. Thermal analysis is one such way to fulfil these requirements. In the present work, a differential scanning calorimeter (DSC) with a normal pressure cell was used in a grease laboratory. By varying the atmosphere and the heating rate, different tests were worked out. The effects of changing physical parameters, such as viscosity and thickener structure, or chemical parameters, such as additives and thickener types, were examined. These methods can be used for controlling raw materials, improvement of grease formulations and production processes, development of new products, as a replacement for the oxidation bomb (ASTM D-942, DIN 51 808), and as a screening test for the FE9 life (DIN 51 821) test rig. [source] Influence of testing parameters on the corrosion rate of magnesium alloysMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 6 2004M. Kühlein Abstract In sodium chloride solutions alloy composition, phases, microstructure and grain size influence the corrosion behaviour of magnesium alloys. Concentration and distribution of the critical impurities iron, nickel and copper affect the corrosion performance strongly. Salt spray tests according to ASTM B 117 or DIN 50021 are used to control quality of magnesium alloys. Results of these tests often estimate alloy subcontractors and are therefore very important to placing. Standards specify test solution, test temperature and position of specimens during test in the salt spray chamber. Standards not prescribe preparation of test specimens, exposure period, handling of the specimens after salt spray test nor the interpretation of the results. Results of salt spray tests can be only compared, provided that test conditions are exactly given. Whether the standards fulfil the above described criteria, will be shown by extensive investigations. Therefore the influence of exposure period, surface condition and microstructure was investigated. [source] Imperfection Sensitivity and Limit Loads of Spherical Shells under Radial PressurePROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2005Jens Pontow The evaluation of the imperfection sensitivity of shell structures and the estimation of their limit loads are widely discussed phenomena. The perturbation energy concept according to Dinkler et al. [1], [2] enables to assess the imperfection sensitivity of shell structures by means of an energy value, the perturbation energy. A buckling criterion may be developed from the comparison between the perturbation energy and experimental data. This paper focuses on the imperfection sensitivity and limit loads of spherical shells of revolution under radial pressure. The investigations include the influence of the meridional angle and different types of boundary conditions. By comparing the numerical results with the German design rule DIN 18800, critical values for the perturbation energy are derived to predict the limit loads. These critical values for the perturbation energy allow to judge whether the German design rule DIN18800 predicts the limit loads of spherical shells under external pressure with varying meridional angles and different boundary conditions with the same reliability in respect of the perturbation energy. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Analytische Herleitung von Anforderungen an den Luftschallschutz zwischen RäumenBAUPHYSIK, Issue 4 2009Beratender Ingenieur VBI Wolfgang Moll Prof. Ing. Schall; Technische Regelwerke; sound protection and acoustics; technical recommendations Abstract Vor dem Hintergrund der Auseinandersetzungen um die Höhe des Schallschutzes der zurzeit überarbeiteten DIN 4109 "Schallschutz im Hochbau" befasst sich der Autor kritisch mit der bisherigen Art der Festlegung bauakustischer Anforderungen. In Anbetracht der fehlenden physikalischen Legitimation dieser Anforderungen , früher an die Schalldämmwerte, jetzt an die Schallschutzwerte , schlägt der Verfasser die gezielte Berechnung der nachhallzeitbezogenen Schallschutzanforderungen vor, und zwar auf der Basis allgemein bekannter Ausgangsdaten, wie z. B. der Schallleistung der einzelnen Quellen, der Verdeckung durch den Grundpegel etc. Das Verfahren wird ausführlich erläutert und beispielhaft erklärt. Für die Abstufungen Mindestschallschutz, erhöhter Schallschutz, hoher Schallschutz werden Basiswerte vorgeschlagen, die dann in die gezielte Bestimmung der Anforderungsgrößen einfließen. Analytical derivation of requirements for airborne sound insulation between rooms. Against the background of the debate about sound protection levels in the current revision of DIN 4109 "Sound insulation in buildings" the author critically examines the existing methodology for determining acoustic requirements. In view of the lack of physical legitimation of these requirements , previously sound insulation values, now sound protection values , the author proposes targeted calculation of reverberation-related sound protection requirements based on generally known basic data, including the sound power levels of individual sources, masking through background noise, etc. The technique is explained in detail and illustrated by means of examples. Basic values are proposed for minimum sound protection, increased sound protection and high sound protection, which are then used for determining the requirements for individual parameters. [source] Entwicklungsgeschichte des zweischaligen Mauerwerks und die neue Norm DIN 1053-12BAUPHYSIK, Issue 4 2009Helmut Künzel Dr.-Ing. Abstract No Abstact [source] Qualitätsprüfung für Energieausweis-SoftwareBAUPHYSIK, Issue 3 2009Klaus Fehlauer Prof. Dr. Dr. Energieeinsparung; Technische Regelwerke Abstract Nach der Einführung der Energieeinsparverordnung 2007 (EnEV 2007) beauftragte das Bundesamt für Bauwesen und Raumordnung (BBR) ein Forschungsprojekt, um die am Markt verfügbare Software zur EnEV 2007 einer Qualitätsprüfung zu unterziehen. Der Zweck des Projektes war die Prüfung hinsichtlich einer korrekten Nachweisführung und Energiepassausstellung sowie die Erarbeitung von Methoden zur Qualitätsprüfung und -sicherung mit dem Ziel, Transparenz bei den am Markt vorhandenen Softwarelösungen zu schaffen. Darüber hinaus sollte durch die Bereitstellung von Testmodulen die Möglichkeit geschaffen werden, vorhandene Softwareprodukte durch das Aufdecken von Mängeln stetig weiter zu entwickeln, um so die Qualität der Produkte auf hohem Niveau dauerhaft zu sichern. Es wurden 15 Softwareprogramme für Nichtwohngebäude und 13 Programme für Wohngebäude für die Bedarfsberechnung nach DIN 4108-6 und DIN V 4701-10 und für Verbrauchsausweiserstellung untersucht. Im Rahmen dieser Veröffentlichung wurden schwerpunktmäßig die Ergebnisse für die Bedarfsberechnungen auf Basis von DIN V 18599 für den Nichtwohngebäudebereich vorgestellt. Quality tests for Energy Passport software. Shortly after the introduction of the 2007 Building Energy Conservation Ordinance (EnEV 2007), the German Institute for Applied Information Technology in Construction (IAIB) was commissioned by the German Federal Office for Building and Regional Planning (BBR) to carry out quality tests for the EnEV 2007 software available on the market. The specified project aims were to check calculation and Energy Passport issuing procedures and the development of quality assurance methods with the aim of creating transparency regarding the software solutions available on the market. 15 software programs for office buildings and 13 software programs for residential buildings were examined with regard to the determination of energy demand according to DIN V 18599 and with regard to energy consumption. [source] Untersuchung des Wärmeschutzes von Außenecken über unbeheizten Kellern in Wohngebäuden , die Achillesferse von massiven Außenwänden mit äußerer Wärmedämmung?BAUPHYSIK, Issue 4 2004Christoph Geyer Dr. rer. nat. Außenwände von Wohngebäuden werden häufig als massive Mauerwerkswände mit einer außenliegenden Wärmedämmung erstellt. Bei dieser Wandkonstruktion trennt aber der Mauerwerkssockel der massiven Außenwand im Erdgeschoß die Wärmedämmebene der Außenwand von der Wärmedämmebene der Kellerdecke über einem unbeheizten Keller. Hierdurch entsteht eine linienförmige Wärmebrücke. Die für den Mindestwärmeschutz kritischste Stelle tritt an der Außenecke im Erdgeschoß auf, wo sich je zwei dieser linienförmigen Wärmebrücken überlagern. Daher wird die minimale raumseitige Oberflächentemperatur an dieser Ecke für die Beurteilung des Mindestwärmeschutzes der Konstruktion herangezogen. Durch eine Vielzahl von dreidimensionalen Wärmebrückenberechnungen werden die Konstruktionseigenschaften der angrenzenden ebenen Bauteile herausgearbeitet, welche die minimale, raumseitige Oberflächentemperatur in der Außenecke über einem unbeheizten Keller und damit den Mindestwärmeschutz der Konstruktion beeinflussen. Es zeigt sich, daß eine minimale raumseitige Oberflächentemperatur in der Außenecke von 12, 6 °C erst mit Wärmedurchlaßwiderständen der Tragschale bzw. der gesamten Wandkonstruktion nachgewiesen werden kann, die wesentlich höher als 1, 2 m2K/W sind. Damit ist für diese Art von Außenwänden ein Mindestwärmeschutz nach Tabelle 3, DIN 4108-2 [1] mit einer Anforderung an den Wärmedurchlasswiderstand von R , 1,2 m2K/W nicht ausreichend, um den Mindestwärmeschutz auch für die Außenecke im Erdgeschoß rechnerisch nachweisen zu können. Es wird daher vorgeschlagen, ergänzende Hinweise in die Norm aufzunehmen. Examination of the thermal insulation characteristics of external corners above unheated basements in dwellings , the Achilles' heel of heavy-weight external walls with thermal insulation on the outside? External walls in dwellings consist often of a heavy-weight wall and a thermal insulation fixed outside. With this construction the insulation of the external wall is separated by the plinth of the external wall from the thermal insulation incorporated in the slab above an unheated basement. This results in a thermal bridge along the edge of the basement slab. The most critical point of the construction with regard to thermal protection occurs at the exterior corner at ground floor level, where two linear thermal bridges overlay. For this reason the minimum inner surface temperature of the corner is used to estimate the heat protection of the construction. A number of calculations of the minimum temperature at the interior surface of this three dimensional thermal bridge is performed to evaluate the parameters of the adjacent construction details which affect the minimum temperature at the inner surface of the corner. To reach the minimum temperature at he inner surface of the corner of 12.6 °C demanded by the German standard DIN 4108-2 as the minimum requirement of heat protection for thermal bridges, thermal resistances of the whole wall construction much higher than 1.2 m2K/W are necessary. For this construction type of exterior walls a thermal resistance of 1.2 m2K/W as demanded in table 3 of the German standard DIN 4108-2 as a minimum heat insulation for exterior walls can be shown to be insufficient to assure a minimum temperature of 12.6 °C at the inner surface of the corner at ground floor level. Thus it is proposed to add additional notes concerning this construction type in this standard. [source] Baulicher Brandschutz für großflächige Dächer , Kommentar zur neuen Fassung von DIN 18234BAUPHYSIK, Issue 2 2004Dieter Brein Dipl.-Ing. Dächer, die die in DIN 18234 Teile 1 bis 4 beschriebenen Anforderungen erfüllen, können das Brandschutzniveau von großflächigen Dächern bei Brandbeanspruchung von unten ohne klassifizierbare Feuerwiderstandsdauer erheblich verbessern. Ein Brand im Innenraum wird das Dach damit entweder nicht mehr oder nur noch so verzögert am Brandgeschehen beteiligen können, daß eine rechtzeitig alarmierte und eintreffende Feuerwehr realistische Chancen erhält, das Brandereignis noch auf eine kleinere Fläche beschränkt vorzufinden und bekämpfen zu können. Die Aufnahme von DIN 18234 als ein Regeldachaufbau in die MusterIndustriebau-Richtlinie (MIndBauRL) war ein erster wichtiger Schritt der baurechtlichen Anerkennung dieser Norm. Es bleibt zu wünschen, daß die positiven Möglichkeiten nun auch bei den künftig überarbeiteten bauordnungsrechtlichen Vorschriften anderer Sonderbauten berücksichtigt werden können. Fire safety of large roofs for buildings , commentary on the new version of DIN 18234 Compliance with the requirements of DIN 18234 can significantly improve the fire safety of large roofs without classifiable fire resistance. A fire inside the building is thus prevented from spreading to the roof, or spreading to the roof is delayed to such an extent that the fire brigade, provided it was notified immediately and arrives in good time, has a realistic chance of finding the fire contained within a smaller area, so that it can be dealt with successfully. Inclusion of DIN 18234 as a roof construction standard in the German model guidelines for industrial buildings (MIndBauRL) was a first, but important step for the acceptance of this standard as part of the building regulation framework. It is hoped that the opportunities offered by the standard can now also be taken up in future revisions of guidelines for other special-purpose buildings. [source] Teil 2: Trittschalldämmung , Flankentrittschallpegel und TrittschallminderungBAUPHYSIK, Issue 2 2004Elmar Sälzer Dipl.-Ing. Im Teil 1 [1] der insgesamt dreiteiligen Darstellung des Schallschutzes von Hohlraumböden wurde über die geschichtliche Entwicklung der seit Anfang der 1980er Jahre auf den Markt gekommenen Hohlraumböden, die wesentlichen Konstruktionsprinzipien solcher Böden und über die Schallängsdämmung, dargestellt durch die bewertete Norm-Flankenpegeldifferenz, berichtet. Im vorliegenden zweiten Teil werden die beiden Aspekte der Trittschalldämmung, und zwar des Flankentrittschallpegels , der früher auch als horizontale Trittschalldämmung bezeichnet wurde , und der Trittschallminderung (früher Trittschallverbesserung) dargestellt. Der nachfolgenden Darstellung der beiden Parameter der Trittschalldämmung liegen ca. 150 Messungen im schalltechnischen Labor zu Grunde, die zum großen Teil noch nach DIN 52 210 [3], in jüngerer Zeit selbstverständlich nach DIN EN ISO 140-12 [4] durchgeführt wurden. Sound protection of cavity floors. Part 2: Impact sound insulation , namely impact sound flanking level and impact sound reduction In part 1 [1] of this three-part report on cavity floor sound protection, the history of the development of cavity floors introduced on the market since the early 1980s, the main design principles of such floors, and the concepts of flanking level reduction and weighted standard flanking level difference were illustrated. This second part examines two aspects of impact sound insulation, namely impact sound flanking level , previously sometimes referred to as horizontal impact sound insulation , and impact sound reduction. The following discussion of these two impact sound insulation parameters is based on approximately 150 measurements in an acoustics laboratory. The bulk of the measurements was carried out according to DIN 52 210 [3], more recent measurements according to DIN EN ISO 140-12 [4]. [source] Zur Auswahl eines geeigneten Verfahrens für die Berücksichtigung der Mitwirkung des Betons auf ZugBAUTECHNIK, Issue 7 2010Ulrich Quast Univ.-Prof. i. R. Dr.-Ing. Tension Stiffening; Different Methods; Stress-Strain Relationship; Moment-Curvature Relationship; Cracked Section; Circular Tube Section Stahlbetonbau Reinforced Concrete Construction Abstract Die Auswahl eines geeigneten Verfahrens zur Berücksichtigung der Mitwirkung des Betons auf Zug sollte nach DIN 1045-1:2001-07, 8.5.1 (9), in Abhängigkeit von der jeweiligen Bemessungsaufgabe getroffen werden. In den Erläuterungen zu DIN 1045-1 wird im Heft 525 des DAfStb als einziges Verfahren nur die Verringerung der Betonstahldehnung mit einer modifizierten Spannungs-Dehnungslinie für Betonstahl erläutert. Verfahren, die mittlere wirksame Betonzugspannungen in der Betonzugzone berücksichtigen, werden erwähnt aber nicht erläutert. Mit den Ergebnissen nachgerechneter Moment-Verkrümmungs-Werte von Stahlbetonröhren aus drei Versuchen mit unterschiedlichen Längskräften wird gezeigt, dass die Mitwirkung des Betons auf Zug mit dem Verfahren nach Heft 525 DAfStb nur bei reiner Biegung befriedigend erfasst wird. Bei Biegung mit Längskraft werden besser mittlere wirksame Betonzugspannungen berücksichtigt. Es werden vier unterschiedliche Ansätze für die Betonzugspannungen besprochen. On the selection of an adequate method for considering the contribution of concrete in tension. The selection of an adequate method for considering the contribution of concrete in tension should according to DIN 1045-1:2001-07, 8.5.1 (9), be chosen with respect to the particular design problem. The explanations to DIN 1045-1 in book 525 from DAfStb describe only one method, the method which reduces the steel strain taking a modified stress-strain relationship into account. Methods that consider mean effective concrete stresses in tension are mentioned but not explained. The results of recomputed moment-curvature values from three tests with different longitudinal forces show that the method in book 525 DAfStb covers the contribution of concrete in tension only for reinforced concrete members without longitudinal forces. For members with longitudinal forces methods with mean effective concrete stresses give better agreements. Four different assumptions for the concrete stresses in tension are discussed. [source] Zur Diskussion des Böenreaktionsfaktors G nach DIN 1055-4:2005BAUTECHNIK, Issue 10 2009BayIKBau Robert Hertle Dr.-Ing., Beratender Ingenieur VBI, Prüfingenieur für Standsicherheit vpi Allgemeines; Baumechanik; General Topics; Structural Mechanics Abstract Mit Einführung der DIN 1055-4:2005 fand ein Paradigmenwechsel bei der Beschreibung der Windlasten statt. Das bisherige, deterministische Konzept zur Definition der Windeinwirkung wurde verlassen und durch ein auf stochastischen Überlegungen fußendes ersetzt. Für Konstruktionen und Bauwerke, die nicht schwingungsanfällig unter böigen Windeinwirkungen sind, ergeben sich daraus keine nennenswerten Änderungen bei der rechnerischen Untersuchung. Für die Analyse von schwingungsanfälligen Konstruktionen hat diese Neukonzeption tiefgreifende Konsequenzen. Die bekannte und einfach zu handhabende Ermittlung des Böenreaktionsfaktors auf Grundlage der Normen der achtziger und neunziger Jahre des vergangenen Jahrhunderts wurde durch ein komplexes, unübersichtliches und mit einfachen Ingenieurmethoden nicht mehr zu überprüfendes Berechnungsschema abgelöst. In diesem Beitrag wird dieses Schema diskutiert, und es wird ein einfaches Näherungsverfahren zur Ermittlung der Böenreaktion einer Konstruktion vorgeschlagen, welches, insbesondere vor dem Hintergrund der sonstigen Unschärfen und Unsicherheiten einer Berechnung, ausreichende Genauigkeit zeigt. On the discussion of the gust reaction factor acc. DIN 1055-4:2005. With the introduction of DIN 1055-4:2005 a change of paradigm concerning the description of wind loads took place. The previous concept, based on a deterministic view, was replaced by an approach using stochastic considerations. For constructions and buildings deemed to be not susceptible to gust action, no significant changes within the structural analysis arise. Enormous consequences, on the other hand, have to be faced when analyzing structures susceptible to gust action. The well known and easy to handle method for calculating the gust reaction factor using the standards of the 80th and 90th of the last century, was redeemed by a complex, partly confused calculation scheme which is not checkable with usual engineering tools. In the following paper this calculation scheme is discussed. Following to this discussion, a simplified method for calculating the gust reaction factor is presented. The accuracy of this method lies, having the usual uncertainties and deficits of structural analyses in mind, in an acceptable range. [source] Die neue Schneelastnorm DIN 1055-5, kritisch hinterfragtBAUTECHNIK, Issue 10 2009Wolfgang Schwind Dipl.-Ing. (FH) Die neue Schneelastnorm DIN 1055-5:7/2005 brachte vor allem in den höhergelegenen Orten der Zone 3 erhebliche Erhöhungen der Schneelast, die bis zum Zweifachen der bisher anzusetzenden Belastung reicht. Auch die neuen Formeln für die Belastung von aneinandergereihten Dächern, von Shed- und Tonnendächern sowie die Behandlung von Höhensprüngen und Trauflasten erscheint problematisch. In diesem Beitrag wird versucht, Unstimmigkeiten der Norm aufzuzeigen. The current snow load standard DIN 1055-5 , a critical review. The current snow load standard DIN 1055-5:7/2005 caused a considerable increase of snow load, particularly in more elevated areas located in zone 3. It doubles the amount of snow load capacity , compared to the old standard. The new equations for calculating snow loads for adjacent roofs, shed roofs and arched roofs as well as the handling differences in altitude and gutter load seems problematic. This paper tries to show the inconsistencies of current standard. [source] DIN 1052:2008-12 Neue Grundlagen für Entwurf, Berechnung und Bemessung von Holzbauwerken , Teil 5 (2): Aussteifungen von Holztragwerken (Fortsetzung aus Heft 7/09 und Schluss)BAUTECHNIK, Issue 8 2009Karin Lißner Dr.-Ing. Holzbau; Timber Construction Abstract Es werden die Grundlagen zur Aussteifung von Holztragwerken dargelegt und an Beispielen erläutert. DIN 1052:2008-12 , New basics for design, calculation and dimensioning of timber structures, Part 5 (2): Construction of bracing in wooden structures. Basics of bracing in wooden structures are given and amplified by several examples. (Continuation of part 5 (1), number 7/09) [source] Nutzungskosten: DIN 18960-2008 , Leistungsfähige Grundlage für die zielorientierte Planung der LebenszykluskostenBAUTECHNIK, Issue 7 2008Udo Blecken em. Die DIN 18960 , Nutzungskosten im Hochbau , ist in überarbeiteter Form im Februar 2008 herausgegeben worden. Sie ist durch Ergänzungen zu einem vollumfänglichen Controllingkonzept (Nutzungskostenvorgabe, -ermittlung, -kontrolle und -steuerung) weiterentwickelt worden, die dem Bauherrn eine kostengesicherte Nutzungskostenplanung ermöglicht. Mit dieser Norm liegt nun eine ökonomisch und ökologisch wichtige Grundlage für den Planungsprozess vor. Im Folgenden sollen die Neuerungen der Norm 18960 beschrieben, die angrenzenden Normen und wichtigen Merkmale erläutert, das Controllingkonzept inkl. eines Berechnungsbeispiels unter Einschluss von Risikoüberlegungen dargestellt und Planungsvertragsfragen besprochen werden. User costs of buildings DIN 18960 , a performance basis for planning of life cycle costs. An updated version of the DIN 18960 , user costs of buildings , has been published in February 2008. The norm has been further developed with supplements to a comprehensive controlling concept (usage cost estimate, usage cost calculation, usage cost monitoring and usage cost management), which provides the builder with the tools to plan the usage costs in a cost-controlled manner. This norm, furthermore, provides an economically and ecologically important basis for the planning process. The new aspects of the DIN 18960 are outlined, the related norms and important features are explained, the controlling concept including a calculation example that considers risk factors is described and questions regarding planning contracts are discussed. [source] Beitrag zur Berechnung der Durchbiegung von Stahlbetonbauteilen und Kritik an der ÖNORM B 4700BAUTECHNIK, Issue 5 2008Zivilingenieur für Bauwesen i. R. Friedrich Schäfer Dipl.-Ing. Im Folgenden wird eine Berechnung der Durchbiegung des Stahlbetons angegeben. Diese unterscheidet sich gegenüber früheren Durchbiegungsberechnungen der ÖNORM B4700 , Stahlbetontragwerke (EUROCODE-nahe Berechnung, Bemessung und konstruktive Durchbildung) , und ÖNORM B4200/8 dadurch, dass unter anderem Versuchsresultate berücksichtigt und die Vorgänge wirklichkeitsnah erfasst werden. Die nach den oben genannten ÖNORMEN berechneten und überhöhten Tragwerke in Österreich sind nach Jahrzehnten noch überhöht. Dies kann unter anderem als Indiz für eine falsche Durchbiegungsberechnung angesehen werden. Es wird daher empfohlen, die in der ÖNORM B4700 , Stahlbetontragwerke , angegebene Berechnungsmethode der Durchbiegung des Stahlbetons erstens aus der Norm zu entfernen, da diese, wie wir zeigen werden, nicht richtig ist; zweitens sich wie in der DIN 1045 auf eine Angabe der Schlankheiten zu beschränken und eventuell die Durchbiegung nach den hier angegebenen Überlegungen zu berechnen und drittens diese dem Bauingenieur zu überlassen und auf diese Weise auch die Qualen der Bauingenieure zu beenden. Da die Normen auch den Stand der Technik darstellen und eingehalten werden müssen, stellt dies zusätzlich ein rechtliches Problem dar. Wie gezeigt wird, beinhaltet die angegebene Methode der Berechnung der Durchbiegung in der ÖNORM B4700 schon im Ansatz schwere Gedankenfehler und falsche Voraussetzungen. A contribution to the calculation of the deflection of reinforced concrete members. Stated below you will find a calculation of the deflection of reinforced concrete. It differs from former calculations of the deflection according to the Austrian standard ÖNORM B4700 , reinforced concrete structures (EUROCODE-based calculation, dimensioning and constructive design) , and Austrian standard ÖNORM B4200/8 in that it takes into consideration, among others, the results of tests and represents the processes realistically. The load-bearing structures in Austria which were calculated according to the above-mentioned Austrian standards and feature a precamber still have a camber after decades. This may be regarded, among others, as an indication for an incorrect calculation of the deflection. It is therefore requested that the calculation method for the deflection of reinforced concrete specified in ÖNORM B4700 , reinforced concrete structures , firstly, be removed from this standard because it is not correct, as will be shown; secondly, restrict itself to stating the slendernesses, as is the case with DIN 1045, and to calculate the deflection according to the considerations contained in this paper, for example; and thirdly, to leave the calculation method to the structural engineers, which would also put an end to their anguish. Since the standards also represent the state of the art and have to be observed, this additionally poses a legal problem. As will be shown, the method for calculating the deflection according to ÖNORM B4700 contains serious errors of thought and wrong presuppositions in its basic approach, already. [source] DIN 1052:2004 , Neue Grundlagen für Entwurf, Berechnung und Bemessung von Holzbauwerken , Teil 3: Bemessung von einteiligen HolzbauteilenBAUTECHNIK, Issue 4 2008Karin Lißner Dr.-Ing. Es werden die Nachweise für die Grenzzustände der Tragfähigkeit für einteilige Holzbauteile unter Zug-, Druck- und Biegebeanspruchung beschrieben. DIN 1052:2004 , New basics for design, calculation and dimensioning of timber structures, Part 3: Ultimate limit states design method of Timber elements. This Article describes the verification of load bearing safety for timber elements, which are stressed from tension, compression and bending according to the ultimate limit state design method. [source] Verdichtungserddruck bei leichter VerdichtungBAUTECHNIK, Issue 3 2008Dietrich Franke Univ.-Prof. i. R. Dr.-Ing. habil. Der Erddruck auf hinterfüllte Wände wird durch die Verdichtung der Hinterfüllung erhöht. In vielen Fällen reicht eine leichte Verdichtung zur Vermeidung größerer Setzungen aus. In Auswertung entsprechender Erddruckmessungen, die in der Vergangenheit in Stuttgart und Dresden durchgeführt wurden, lassen sich die Angaben der neuen DIN 4085 für leichte Verdichtung ergänzen, wenn bestimmte Einschränkungen bei der Auswahl der Verdichtungsgeräte eingehalten werden. Earth pressure due to light compaction. The earth pressure acting on backfilled walls is increased by compaction. A light compaction suffices in many cases to prevent larger settlements. Earth pressure measurements were performed in the past in Stuttgart and Dresden. Based on these measurements, the specifications of the new DIN 4085 are complemented for light compaction. [source] Nachweis der Gebrauchstauglichkeit von Bauteilen aus Stahlbeton nach DIN 1045 und nach EC 2BAUTECHNIK, Issue 10 2007Richard Friedrich Dr.-Ing. Der Beitrag behandelt die häufig vorkommenden biegebeanspruchten Bauteile mit rechteckförmigem Querschnitt aus normalfestem Normalbeton C 20 bis C 50 mit einseitiger Bewehrung aus Betonstahl BSt 500. Bei der Berechnung der Durchbiegung w wird das Betonkriechen und -schwinden berücksichtigt, bei der Berechnung der Rißbreite wk und der Spannungen ,c und ,s das Kriechen allein. Design of reinforced concrete members for serviceability after DIN 1045 and after EC 2. Considered are the frequently used members with rectangular cross section in normal strength normal concrete C 20 up to C 50 and one-sided reinforcement with steel BSt 500. For the calculation of the deflection w, both concrete creep and shrinkage are taken into consideration, for the calculation of the crack width wk and the stresses ,c and ,s the creep only. [source] | ||||||||||||||||||||||||||||||||||