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Vývoj nového druhu lehčeného podlahového potěru se samonivelační funkcí / Development of a new type of lightweight self-levelling floor screedŠenk, Josef January 2015 (has links)
This thesis is focused on development of a new type of lightweight self-levelling floor screed. The aim of this thesis is to develop lightweight screed with self-levelling function, which could be stored in a dry mixture in bags or silos, designed for use with only addition of water.
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En utredning av olika miljöaspekters betydelse vid renovering / A study on the importance of different sustainability aspects in real estate renovationStanojlovic, Natalija, Nordström, Oscar January 2020 (has links)
De senaste åren har frågan om hållbar utveckling tagit allt större plats i samhällsdebatter. När det gäller fastighetssektorn har denna fråga och miljömål främst riktats mot nybyggnationer. Samtidigt byggdes majoriteten av fastigheterna i Sverige innan 1970 och ersätts av nya byggnader i en hastighet på 1–3% per år. Med det i åtanke påträffas ett stort gap som den här studien har för avsikt att adressera. Detta genom att undersöka miljöaspekters påverkan vid renoveringar av byggnader och specifikt med hänsyn till materialval av golv. Studien undersöker tre olika perspektiv. Genom en litteraturstudie har ett urval av golvmaterial utretts med avseende på klimatpåverkan mätt som Global Warming Potential (GWP100), energiåtgång och kemiska restprodukter. Därefter har en analys gjorts över vilka krav och riktlinjer som ställs från miljöcertifieringssystemets sida genom en dokumentanalys och slutligen har miljöaspekternas betydelse vid renovering ur ett fastighetsbolags perspektiv undersökts genom en fallstudie hos fastighetsbolaget Hufvudstaden. Litteraturstudien visade på, för de undersökta miljöaspekterna, att linoleumgolv presterar bäst på en kort tidshorisont på 8 år och parkettgolv presterar bättre än de andra golvtyperna i en tidshorisont på över 20 år. Ett flertal av de inhämtade studierna undersökte även kemiska restprodukter, slutsatsen blev att de ämnen som studierna tog upp inte anses att vara farliga. Däremot bör det ej uteslutas att golven kan producera andra kemiska restprodukter som kan ha en negativ påverkan på sin omgivning. Gällande certifieringssystemen framgick det att material har en mindre roll i certifieringsprocessen, maximalt 12—14 % av de totala poängen. Det visade sig att de lägger vikt på att renoveringsarbete tidigt planeras för hållbara processer, bland annat genom att välja material med hållbarhet i åtanke och underhålla det med omsorg. Utifrån certifieringssystemens villkor och rekommendationer ses parkettgolv som det mest lämpade valet utav de undersökta golvtyperna. I fastighets- och byggbranschen premieras oftast parkettgolv utav de undersökta golven i detta arbete. Både IVL Svenska Miljöinstitutet och fastighetsbolaget Hufvudstaden anser att golvet är det mest lämpade vid renoveringar med en lång livslängd i åtanke. / The issue of sustainability has been highlighted more frequently in recent years. In the case of the real estate industry the environmental objectives have primarily been set with respect to new construction. However, the majority of the properties in Sweden were built before the 1970’s and buildings are replaced at a rate of only 1-3% per year. Keeping this in mind, an important research gap is present. This study aims to contribute to the narrowing of that gap by examining the environmental impacts of renovations in existing buildings and specifically with respect to the choice of flooring materials. The study was conducted through three perspectives. Firstly, by examining literature on a selection of flooring materials with regards to Global Warming Potential (GWP100), energy consumption and chemical residues. Secondly by analyzing guidelines provided by sustainability certifications through a document analysis. The last perspective was studying the choice of flooring material from a real estate company point of view, conducted through a case study. The literature study showed, for the investigated environmental aspects, that linoleum floors perform best on a short time horizon of 8 years and parquet floors perform in a longer time horizon of over 20 years. A number of the examined studies also investigated the chemical residues from the materials that may have a negative impact on the environment, but the conclusion was that the substances were not shown to be dangerous. However, it should not be ruled out that the floors may produce other chemical residues that may have a negative impact on their surroundings. Regarding the certification systems, it was found that materials play a smaller role in the certification process, a maximum of 12-14% of the total points. It turned out that certification systems place emphasis on early planning for sustainable processes in construction, including choosing materials with sustainability in mind and maintaining them with care. Based on the conditions and recommendations of the certification systems, parquet floors are seen as the most suitable choice of the floor types examined. The real estate and construction industry commend the parquet floors out of the examined flooring types, due to its ability to be maintained and its long life-span.
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Le processus d'innovation environnementale face à ses contradictions : le cas du secteur des revêtements de sol résilients / The process of environmental innovation facing up its contradictions : the case of the sector of resilient flooringDebref, Romain 13 October 2014 (has links)
Comme une sorte de revers de la médaille, la fin des « Trente Glorieuses » est marquée par la reconnaissance de la problématique environnementale et les crises pétrolières des années 1970. La première grande conférence de l'ONU consacrée à l'environnement humain à Stockholm en 1972 se déroule dans contexte où scientifiques, industriels et politiques s'interrogent sur les modalités permettant de créer un nouveau modèle de société. De la croissance « vertes » en passant par la décroissance, les propositions ne manquent pas. Depuis le Sommet de la Terre de Rio en 1992, c'est du côté du changement technique, de l'innovation et des industriels que tous les regards sont rivés aujourd'hui. Seulement, la doctrine de l'innovation environnementale et les méthodes en matière d'éco-conception restent fragiles.Depuis la Révolution industrielle, le secteur des revêtements de sol résilients, ou souples, accompagne l'évolution des modes de vie au sein des habitations et représente un symbole d'une société de consommation de masse. Aux proies aux controverses, nous nous proposons de décrire comment les industriels de ce secteur gèrent et intègrent la pression environnementale ; et en particulier comment, de fait, mobilisent-ils le processus d'innovation environnementale pour résister à cette pression. / As a kind of a flipside of the coin, the end of the "Thirty Glorious Years" is marked by the recognition of environmental issues and the oil crises of the 1970s The first major UN conference dedicated to the Human Environment in Stockholm 1972 takes place in context where scientists, industrialists and politicians are questioning the methods for creating a new model of society. To The “Green Growth” to “degrowth”, proposals abound since this last decade. Since the Earth Summit in Rio in 1992, technical change, innovation and industry are the center of attention. But the doctrine of environmental innovation and methods for eco-design are still fragile.Since the Industrial Revolution, the sector of resilient floorings follows lifestyles whilst keeping its symbol of a society of mass consumption. Prey to controversies, we propose to describe how the industry manage and integrate environmental pressure; and especially how they mobilized the process of environmental innovation to withstand pressure.
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Indicadores críticos da manufatura de pisos de madeira maciça / Critical indicators applied to manufacture of solid wood flooringSoares, Philipe Ricardo Casemiro 27 January 2010 (has links)
A implementação de programas de qualidade na linha de produção tem sido utilizada por empresas para garantir a competitividade em um mercado cada dia mais competitivo. A busca por equilíbrio entre qualidade e custos é uma constante na área industrial e, neste contexto, melhorias no processo produtivo são fundamentais. No setor florestal, responsável por 3,5% do PIB do país em 2007, a gestão da qualidade aplicada à linha de produção é recente e muitos aspectos importantes não são considerados. O objetivo deste trabalho foi identificar e avaliar os pontos críticos do processo de produção de uma empresa de processamento da madeira. Para tanto, a pesquisa foi dividida em três etapas. A primeira foi o mapeamento do processo da empresa e a elaboração de fluxogramas para as atividades. A segunda fase foi a identificação e avaliação dos pontos críticos por entrevistas com funcionários, utilizando metodologia FMEA (Failure Mode and Effect Analysis) e diagramas de Ishikawa, que relaciona as falhas com suas possíveis causas. A terceira fase foi a avaliação do processo produtivo, empregando o controle estatístico do processo nos principais pontos críticos e a determinação da capacidade do processo pelo índice Cpk. Os resultados mostraram a existência de 6 sub-processos, sendo dois críticos. Nesses setores foram identificados 15 pontos críticos, com cinco deles selecionados para serem avaliados. Os gráficos de controle para variáveis indicaram que o processo produtivo da empresa é instável quanto ao item peças fora de dimensão em ambos setores, enquanto o índice Cpk permitiu concluir que a empresa não é capaz de produzir pisos de madeira dentro das especificações. Para os atributos, o processo era estável, exceto para peças marcadas pela lixa. A causa de não conformidades mais significativa foi a aferição dos equipamentos de medição, que resultou em processos com baixa variação, porém com médias distantes das especificações. / The implementation of quality programs in line production has been used by companies to guarantee the competitiveness in a market more competitive every day. The search for balance between quality and costs is a constant in industrial area and, in this context, improvements in the productive process are fundamentals. In the forest sector, responsible for 3,5% of the countrys GDP in 2007, the quality management applied to the line production is recent and many important aspects are not considered. This study aimed to identify and evaluate the critical points of the process of production of a company of wood processing. Therefore, the research was divided in three stages. The first one was the process mapping of the company and the elaboration of flowcharts for the activities. The second phase was identify and evaluate the critical points for interviews with employees, using FMEA (Failure Mode and Effect Analysis) methodology and Ishikawas diagram, which relates the failure with their possible causes. The third phase was the evaluation of the productive process, applying statistical process control in the main critical points and the determination of the process capability for the Cpk index. The results showed the existence of 6 processes, two of them critical. In those sectors 15 critical points were indentified and 5 were selected for evaluation. The control charts for variables indicated that the process is unstable for the item pieces out of dimension in both processes, while the Cpk index allowed to conclude that the company is not capable to produce wood flooring according to the specifications. For the attributes, the process was stable, except for pieces marked by the sandpaper. The more significant cause of non-conformities was the gauging of the measurement equipments, that resulted in processes with low variation, however with means far from the specifications.
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Emissions of organic compounds from technosphere articles : Measurements and modeling of mass transfer from consumer goods and building materials to air and waterHolmgren, Tomas January 2013 (has links)
This thesis describes the development of a generic model for predicting the emissions of organic compounds from materials used in the manufacture of various goods and products. Many products contain organic substances that are not bound to the matrix formed by their constituent materials and are thus able to dissociate from the material and become transferred into the surrounding environment. A wide range of materials and products are used in modern societies, and many compounds deriving from these materials are regarded as emerging pollutants in both indoor and outdoor environments. The model uses three components to describe the transfer of compounds from materials to the surrounding environment: partitioning of the compound between the material and its surroundings based on linear free energy relationships, diffusion within the material based on the Piringer equation, and convective mass transfer in air or water based on an empirical flat surface model. The model’s predictive capacity was tested against three experimental case studies: emissions of plasticizers from vinyl flooring and triphenyl phosphate from LCD screens into the air, and leaching of organophosphates from concrete into water. The rates of emission from vinyl flooring were clearly affected by the number of layers comprising the material. Triphenyl phosphate was found in the front surface of all tested flat screens and its rates of emission were related to the nature of the screen and its operating temperature. The model accurately predicted emissions into the air and leaching from concrete into water once modified to include modules that describe dissolution from surfaces and diffusion in water-filled pores. The model was then used to investigate emissions on the national scale. It was found that the rates of emission from vinyl flooring are not changing over time, and that the total mass of emitted material is dependent on annual sales volumes and the expected life span of the vinyl flooring. Moreover, the additive used has a large effect on the emitted mass. Emissions from flat screen displays depend strongly on their operating temperatures: displays with high working temperatures that are active for extended periods of time produce more emissions. The model was also used to study the release of organophosphates from the concrete used to make a bridge, which depended on the flow of water under the bridge, the temperature, the porosity of the concrete, and the additive’s water solubility. Data on annual sales volumes and the total surface area of sold goods are essential when studying emissions on a national scale. National retailers’ organizations are valuable sources of such information. When adequate data are not available, it is necessary to perform uncertainty analyses to determine the impact of uncertainty in the modeling of different stages of the emissions process in different scenarios.
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Evaluating profitability of solid timber production from 15 year old pruned and thinned Eucalyptus nitens (Deane & Maiden) in CanterburySatchell, Stuart Dean January 2015 (has links)
This case study investigated profitability of a small stand of fast-grown Eucalyptus nitens in Canterbury for sawn timber production. This stand was pruned and thinned and then harvested at 15 years old. An estimate of per-hectare log yields and diameters was made from the stand. Sample logs were sawn, dried and profiled, then products quantified. Log prices were estimated using the residual value method. Prices were summed for sawn products from each log, from which processing expenses and sawmill profit were deducted for an estimate of log value. In the absence of market prices for sawn E. nitens products empirical estimates of price were derived from market survey data. Predictive models were produced from estimated stand log yields along with predicted product revenues and processing costs from sample logs. These were used for estimating per-hectare log residual values from the case study stand trees. Financial returns to the grower were then calculated as discounted cash flows from the estimated log residual values per hectare, taking into account grower costs along with harvesting and transport costs. Best-practice processing methods were identified from the literature and applied as a productivity benchmark. Methods were developed with the view to standardising data across research efforts that seek to improve grade recoveries for E. nitens. A range of factors were investigated that potentially influenced E. nitens log residual value in this case study, including log diameter and log position. Outcomes included a reasonably favourable return on investment for the grower. However, this depended on a number of factors such as land price, distance from processor, product prices, grading methods, drying methods and level of sawmill profit. The application of contemporary best practice small-scale processing methods indicates that E. nitens has potential as a profitable plantation species for solid timber production.
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Avaliação estrutural de um pavimento flexível de base constituída de solo laterítico, através dos ensaios deflectométricos e pressiométricos. / Structural evaluation of a flexible base floor composed of lateritic soil, through the deflectometric and pressiometric tests.RODRIGUES, John Kennedy Guedes. 07 November 2018 (has links)
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Previous issue date: 1992-07 / Este trabalho consiste na avaliação estrutural de um pavimento flexível de base constituída de Material laterítico, localizado entre os municípios de Sapé, Marí e Guarabira (PB-055), objetivando avaliar o desempenho estrutural da base, bem como das outras camadas que compõem o pavimento, ao longo de 7km. Para isso, como forma de obtenção de parâmetros estruturais para posterior avaliação, optou-se pelos seguin tes ensaios: a) Ensaio Deflectométrico com a viga Benkelman, utilizando-se "metodologia
não destrutiva, para avaliação estrutural de pavimentos flexíveis, através da interpretação das Bacias de Deformação" Desenvolvida pelos professores." João M . Fabrício at alii 1988); b) Ensaio Pressiométrico com o Pressiômetro de Pavimentação,
desenvolvido por Briaud e Shields na Universidade de Ottawa no Canadá (1979), ensaiando a sub-base e o subleito. Os parâmetros estruturais, obtidos com os respectivos ensaios, além de servirem como indicadores das condições estruturais das camadas do pavimento, foram correlacionados e ajustados matematicamente. No tocante ao desempenho da base laterítica e do pavimento como um todo, observou-se que os parâmetros estruturais deflectométricos obtidos se enquadram dentro dos limites pré-estabelecidos pela metodologia adotada, o que confirmou o seu bom desempenho. Com relação às ajustagens, foram obtidas equações bastante significativas. O que demonstra uma alta afirmação dos dois ensaios utilizados nesta pesquisa, respaldando seus valores teóricos e interpretativos, muito bons para serem utilizados como parâmetros de avaliação de pavimentos flexíveis. / This work describes the structural evaluation of a flexible pavement, 7 Km long linking the districts of Sapé, Marí and Guarabira (PB- 055) Paraiba State, Northeast Brazil. The structural performance of its layers including the lateritic basement was investigated and data were obtained following the methology described below: a) Test Deflectometer with the B e n k e 1 m a n Bean following a. Nondestructive methodology for the evaluation of flexible pavements through the interpretation of the "Basin Deflection" developed by J.M. Fabricio et al (1988); b) Pressuremeter test of both the sub-grade and the sub-base by using the pressuremeter of pavements developed by Briaud and Shields (1979). The results analysed helped as indicators the structural conditions of the layers and also were correleted and adjusted mathematically for the derivation of equations. the structural deflectometric parameters determined for the lateritic basement and for the methodology used and confirmed it's good performance. Analysis of the significant equations developed in this study renders support for the good quality of the tests performance during the investigations recommending them very good for that evaluation of flexible pavements.
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Indicadores críticos da manufatura de pisos de madeira maciça / Critical indicators applied to manufacture of solid wood flooringPhilipe Ricardo Casemiro Soares 27 January 2010 (has links)
A implementação de programas de qualidade na linha de produção tem sido utilizada por empresas para garantir a competitividade em um mercado cada dia mais competitivo. A busca por equilíbrio entre qualidade e custos é uma constante na área industrial e, neste contexto, melhorias no processo produtivo são fundamentais. No setor florestal, responsável por 3,5% do PIB do país em 2007, a gestão da qualidade aplicada à linha de produção é recente e muitos aspectos importantes não são considerados. O objetivo deste trabalho foi identificar e avaliar os pontos críticos do processo de produção de uma empresa de processamento da madeira. Para tanto, a pesquisa foi dividida em três etapas. A primeira foi o mapeamento do processo da empresa e a elaboração de fluxogramas para as atividades. A segunda fase foi a identificação e avaliação dos pontos críticos por entrevistas com funcionários, utilizando metodologia FMEA (Failure Mode and Effect Analysis) e diagramas de Ishikawa, que relaciona as falhas com suas possíveis causas. A terceira fase foi a avaliação do processo produtivo, empregando o controle estatístico do processo nos principais pontos críticos e a determinação da capacidade do processo pelo índice Cpk. Os resultados mostraram a existência de 6 sub-processos, sendo dois críticos. Nesses setores foram identificados 15 pontos críticos, com cinco deles selecionados para serem avaliados. Os gráficos de controle para variáveis indicaram que o processo produtivo da empresa é instável quanto ao item peças fora de dimensão em ambos setores, enquanto o índice Cpk permitiu concluir que a empresa não é capaz de produzir pisos de madeira dentro das especificações. Para os atributos, o processo era estável, exceto para peças marcadas pela lixa. A causa de não conformidades mais significativa foi a aferição dos equipamentos de medição, que resultou em processos com baixa variação, porém com médias distantes das especificações. / The implementation of quality programs in line production has been used by companies to guarantee the competitiveness in a market more competitive every day. The search for balance between quality and costs is a constant in industrial area and, in this context, improvements in the productive process are fundamentals. In the forest sector, responsible for 3,5% of the countrys GDP in 2007, the quality management applied to the line production is recent and many important aspects are not considered. This study aimed to identify and evaluate the critical points of the process of production of a company of wood processing. Therefore, the research was divided in three stages. The first one was the process mapping of the company and the elaboration of flowcharts for the activities. The second phase was identify and evaluate the critical points for interviews with employees, using FMEA (Failure Mode and Effect Analysis) methodology and Ishikawas diagram, which relates the failure with their possible causes. The third phase was the evaluation of the productive process, applying statistical process control in the main critical points and the determination of the process capability for the Cpk index. The results showed the existence of 6 processes, two of them critical. In those sectors 15 critical points were indentified and 5 were selected for evaluation. The control charts for variables indicated that the process is unstable for the item pieces out of dimension in both processes, while the Cpk index allowed to conclude that the company is not capable to produce wood flooring according to the specifications. For the attributes, the process was stable, except for pieces marked by the sandpaper. The more significant cause of non-conformities was the gauging of the measurement equipments, that resulted in processes with low variation, however with means far from the specifications.
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Ověřování možnosti využití recyklovaného autoskla jako náhrady křemičitého písku v polymerbetonových průmyslových podlahách / The diploma thesis was prepared in cooperation with Atemit. The thesis describes the specific composition and properties of polymer industrial substrates from Atemit research.Šácha, Dominik January 2019 (has links)
This diploma thesis has goal to find out possibility of substitution sand in polymer crete flooring system by recycling car glass. Polymer crete is made from sand and epoxy resin. Companies use it in industrial flooring system. Polymercrete industrial flooring systems are new types of floor surface. It aims to customers with high requirements to floor properties and short time of realisation. Polymercrete floors are 4-6 mm thin. They are waterproof, they has higher compressive strength then 60 MPa and tensile strength is more than 20 MPa. Polymercretes does not make dust. This study includes also suggestion of recycling process to make glass sand from car glass windows. The diploma thesis was prepared in cooperation with company Atemit, s.r.o.
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Analyse der Druckbelastung unter der Rinderklaue mittels eines folienbasierten Druckmesssystems auf verschiedenen StallbödenOehme, Benjamin 26 November 2018 (has links)
Einleitung:
Klauenerkrankungen und Lahmheiten stellen ein großes ökonomisches sowie tierschutzrelevantes Problem in der modernen Milchviehhaltung dar. Diese werden wesentlich durch die Haltung auf harten Böden wie Beton oder Gussasphalt begünstigt. Daher werden in Rinderställen vermehrt Gummi-Laufflächenbeläge eingebaut, welche die mechanischen Belastungen und somit potentielle Schädigungen der Klauen reduzieren sollen. Die Einwirkung von Kräften in Abhängigkeit unterschiedlicher Böden auf die Klauenfußungsfläche kann mittels Druckmessung untersucht werden. Um dabei den direkten kinetischen Einfluss des Bodens auf die Fußungsfläche ermitteln zu können, sind dünne Sensorfolien nötig.
Ziele der Untersuchung:
Ziel der Arbeit war es, zunächst ein Ex-vivo-Belastungsmodell für isolierte Rindergliedmaßen zu etablieren, um mit einem folienbasierten Druckmesssystem den direkten kinetischen Einfluss verschiedener Untergründe auf die Fußungsfläche der Klauen zu ermitteln. Anschließend sollte dieses Messsystem erstmals unter lebenden Rindern angewendet werden.
Tiere, Material und Methoden:
Insgesamt wurden drei Versuche durchgeführt, in denen die kinetischen Einflüsse von Betonboden sowie mindestens einem Gummiboden der Firma Gummiwerk KRAIBURG Elastik GmbH & Co. KG anhand folgender Parameter untersucht wurden: Kraftverteilung, Belastungsfläche sowie durchschnittlicher und maximaler Druck. Die Datenerfassung erfolgte mit dem Hoof™System (Tekscan®). Zunächst wurde ein Ex-vivo-Versuch mit einem speziell für diese Messung angefertigten Belastungsgerät durchgeführt. Damit wurden zwölf linke isolierte distale Hintergliedmaßen auf Betonboden sowie drei Laufgang-Gummimatten (KARERA P, KURA P und profiKURA P) belastet. Außerdem wurde in diesem Versuch neben den oben aufgeführten Parametern zusätzlich die Kraft- und Druckverteilung innerhalb definierter Bereiche unter der Klaue analysiert. Diese Versuchsanordnung wurde anschließend in einen statischen In-vivo-Versuch mit elf auf Beton und KURA P Gummiboden stehenden, adulten Milchkühen überführt. Außerdem wurden die Sensorfolien in einem zweiten In-vivo-Versuch unter den Klauen der linken Hintergliedmaße von zehn adulten Milchkühen angebracht und die kinetischen Einflüsse von Beton und KURA P Gummiboden im Stand und beim Laufen ermittelt. Die statistischen Vergleiche zwischen den Böden wurden gepaart für die Klauen bzw. Kühe sowie zwischen den Versuchen mittels Wilcoxon-Vorzeichen-Rang-Test mit anschließender Post-Hoc-Korrektur nach Bonferroni-Holm berechnet. Für alle Resultate mit einer Wahrscheinlichkeit von p < 0,05 wurde eine statistische Signifikanz angenommen. Zusätzlich wurden im Laufen die Kraft-Zeit-Kurven einzeln für die laterale und mediale Klaue aufgezeichnet.
Ergebnisse:
In allen Versuchen sowie auf allen untersuchten Böden lastete die Kraft signifikant mehr auf den lateralen als auf den medialen Klauen. Die belastete Fläche war auf allen Gummiböden signifikant größer als auf Betonboden. Dadurch zeigten sich auf allen Gummiböden signifikant geringere Druckbelastungen als auf Betonboden: Der durchschnittliche Druck fiel im Ex-vivo-Versuch auf allen untersuchten Gummiböden im Mittel 34 - 44 % geringer aus als auf Betonboden (44,69 ± 5,39 N/cm²), während die Durchschnittsdruckwerte in den In-vivo-Versuchen auf KURA P-Gummiboden im Mittel um 16 - 21 % geringer waren als auf Beton (statisch: 32,05 ± 4,56 N/cm² bis 35,74 ± 7,66 N/cm², dynamisch: 46,60 ± 13,94 N/cm² bis 55,60 ± 9,78 N/cm²). Der auf die Klauen wirkende Maximaldruck war im Ex-vivo-Versuch auf den getesteten Gummiböden im Mittel 33 - 45 % geringer als auf Beton (130,31 ± 23,29 N/cm²) und in den In-vivo-Versuchen auf KURA P-Gummiboden im Mittel 28 - 32 % geringer als auf dem Betonboden (statisch: 92,12 ± 8,83 N/cm² bis 104,79 ± 20,40 N/cm², dynamisch: 158,47 ± 37,66 N/cm²). Die Kraft-Zeit-Kurven des dynamischen In-vivo-Versuchs zeigten weitgehend biphasische Verläufe mit lokalen Maxima bei 29 % und 79 % der Stützphase. Es traten jedoch interindividuell sowie jeweils zwischen lateralen und medialen Klauen deutliche Unterschiede im Kurvenverlauf auf.
Schlussfolgerungen:
Das Hoof™System konnte erfolgreich bei Rindern eingesetzt werden. Mit dem Belastungsgerät konnten standardisierte Messwiederholungen auf verschiedenen Untergründen durchgeführt werden. Künftig können damit weitere Untergründe sowie neue Klauenpflegetechniken zunächst ex vivo evaluiert werden, bevor sie an lebenden Rindern Anwendung finden. In allen Versuchen war auf Gummiboden eine mechanische Entlastung der Klauenfußungsfläche zu verzeichnen, was die Vermutung nahelegt, dass diese Böden einen Beitrag zur nachhaltigen Verbesserung der Klauengesundheit in der konventionellen Milchviehhaltung leisten können. / Introduction:
Claw lesions and lameness are amongst the major problems in modern dairy husbandry. They are mainly caused by keeping the cows on hard, unyielding floors like concrete or mastic asphalt. Therefore preventively, an increasing number of farmers install rubber floorings in the walking alleys to minimize the mechanical stress to the sole and consequently reduce damage of the claws. The kinetic effect of different flooring types to the sole can be analyzed by means of pressure measurement. In order to detect the direct kinetic impact of the tested flooring, thin sensor foils capturing the interactions between claw and floor are required.
Aims of the study:
In the present study, an ex vivo load applicator was to be developed in order to use a foil-based pressure measurement system to determine the direct kinetic effect of different flooring types on the claws’ soles. Furthermore, this system was to be applied to live dairy cows for the first time.
Materials and Methods:
Three trials were conducted in which the kinetic effects of concrete and at least one rubber flooring (Gummiwerk KRAIBURG Elastik GmbH & Co. KG) were analyzed considering the following parameters: force balance, contact area, mean pressure and maximum pressure. Data acquisition was performed with the Tekscan® Hoof™System. Initially, an ex vivo trial was carried out with a purpose-built load applicator. Using this method, twelve left isolated distal hind limbs were loaded on concrete and three rubber floorings (KARERA P, KURA P and profiKURA P). Beside the parameters mentioned above, force and pressure distribution were analyzed within the separate areas of the claw’s sole. Afterwards, this test setting was transposed into a static in vivo trial with eleven adult dairy cows standing on concrete and KURA P rubber mats, respectively. Subsequently, the sensor foils were attached under the left hind limbs of ten adult dairy cows and the kinetic impacts of concrete and KURA P rubber flooring were determined during standing and walking. Statistical analysis was conducted using the Wilcoxon signed-rank test in combination with Holm-Bonferroni post hoc correction. Differences were considered to be significant at p < 0.05. In addition to the parameters mentioned above, force-time-curves of the walking cows were captured separately for the lateral and medial claw.
Results:
In all trials and on all tested floorings load was distributed unevenly between the claws at the expense of the lateral claw. The contact area was larger on all rubber floorings than on concrete. Therefore, the mean and maximum pressure loads were lower on all rubber floorings compared to concrete: In the ex vivo trial the mean pressure was, on average, 34 - 44 % lower on all rubber floorings than on concrete (44.69 ± 5.39 N/cm²), while in the in vivo measures the mean pressure was, on average, 16 - 21 % lower on KURA P rubber flooring compared to concrete (static: between 32.05 ± 4.56 N/cm² and 35.74 ± 7.66 N/cm², dynamic: between 46.60 ± 13.94 N/cm² and 55.60 ± 9.78 N/cm²). The maximum pressure loads in the ex vivo measures were, on average, 33 - 45 % lower on the tested rubber floorings than on concrete (130.31 ± 23.29 N/cm²) and in the in vivo trials, on average, 28 - 32 % lower on KURA P rubber flooring compared to concrete (static: between 92.12 ± 8.83 N/cm² and 104.79 ± 20.40 N/cm², dynamic: 158.47 ± 37.66 N/cm²). The force-time-curves of the dynamic in vivo study essentially showed biphasic curve progression with local peaks at 29 and 79 % of the stance phase. However, considerable differences in the curve progression between individuals as well as between the respective lateral and medial claw were found.
Conclusions:
The Hoof™System was applied successfully in dairy cattle claws for the first time. With the load applicator standardized repeated measurements on different floorings were conducted. In the future, more flooring systems as well as novel claw trimming methods can be evaluated using this setup before they are applied on live cattle. In all trials, a mechanical relief for the sole on the rubber floorings was determined. This leads to the conclusion that these floorings may contribute to a sustainable improvement of claw health in conventional dairy husbandry.
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