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Comparison of geoenvironmental properties of caustic and noncaustic oil sand fine tailingsMiller, Warren Gregory Unknown Date
No description available.
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Optimization of steam/solvent injection methods: Application of hybrid techniques with improved algorithm configurationAlgosayir, Muhammad M Unknown Date
No description available.
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The techno-economics of bitumen recovery from oil and tar sands as a complement to oil exploration in Nigeria / E. OrireOrire, Endurance January 2009 (has links)
The Nigeria economy is wholly dependent on revenue from oil. However, bitumen has been discovered in
the country since 1903 and has remained untapped over the years. The need for the country to
complement oil exploration with the huge bitumen deposit cannot be overemphasized. This will help to
improve the country's gross domestic product (GDP) and revenue available to government. Bitumen is
classifled as heavy crude with API (American petroleum Institute) number ranging between 50 and 110
and occurs in Nigeria, Canada, Saudi Arabia, Venezuela etc from which petroleum products could be
derived.
This dissertation looked at the Canadian experience by comparing the oil and tar sand deposit found in Canada with particular reference to Athabasca (Grosmont, Wabiskaw McMurray and Nsiku) with
that in Nigeria with a view of transferring process technology from Canada to Nigeria. The Nigeria and Athabasca tar sands occur in the same type of environment. These are the deltaic, fluvial marine deposit in an incised valley with similar reservoir, chemical and physical properties. However, the Nigeria tar sand is more asphaltenic and also contains more resin and as such will yield more product volume during
hydro cracking albeit more acidic. The differences in the components (viscosity, resin and asphaltenes
contents, sulphur and heavy metal contents) of the tar sands is within the limit of technology adaptation.
Any of the technologies used in Athabasca, Canada is adaptable to Nigeria according to the findings of this research.
The techno-economics of some of the process technologies are. x-rayed using the PTAC (petroleum
technology alliance Canada) technology recovery model in order to obtain their unit cost for Nigeria
bitumen. The unit cost of processed bitumen adopting steam assisted gravity drainage (SAGD), in situ
combustion (ISC) and cyclic steam stimulation (CSS) process technology is 40.59, 25.00 and 44.14
Canadian dollars respectively. The unit cost in Canada using the same process technology is 57.27, 25.00
and 61.33 Canadian dollars respectively. The unit cost in Nigeria is substantively lesser than in Canada.
A trade off is thereafter done using life cycle costing so as to select the best process technology for the
Nigeria oil/tar sands. The net present value/internal rate of return is found to be B$3,062/36.35% for
steam assisted gravity drainage, B$I,570124.51 % for cyclic steam stimulation and B$3,503/39.64% for in
situ combustion. Though in situ combustion returned the highest net present value and internal rate of
return, it proved not to be the best option for Nigeria due to environmental concern and response time to
production. The best viable option for the Nigeria tar sand was then deemed to be steam assisted gravity
drainage.
An integrated oil strategy coupled with cogeneration using MSAR was also seen to considerably amplify
the benefits accruable from bitumen exploration; therefore, an investment in bitumen exploration in
Nigeria is a wise economic decision. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2010.
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The techno-economics of bitumen recovery from oil and tar sands as a complement to oil exploration in Nigeria / E. OrireOrire, Endurance January 2009 (has links)
The Nigeria economy is wholly dependent on revenue from oil. However, bitumen has been discovered in
the country since 1903 and has remained untapped over the years. The need for the country to
complement oil exploration with the huge bitumen deposit cannot be overemphasized. This will help to
improve the country's gross domestic product (GDP) and revenue available to government. Bitumen is
classifled as heavy crude with API (American petroleum Institute) number ranging between 50 and 110
and occurs in Nigeria, Canada, Saudi Arabia, Venezuela etc from which petroleum products could be
derived.
This dissertation looked at the Canadian experience by comparing the oil and tar sand deposit found in Canada with particular reference to Athabasca (Grosmont, Wabiskaw McMurray and Nsiku) with
that in Nigeria with a view of transferring process technology from Canada to Nigeria. The Nigeria and Athabasca tar sands occur in the same type of environment. These are the deltaic, fluvial marine deposit in an incised valley with similar reservoir, chemical and physical properties. However, the Nigeria tar sand is more asphaltenic and also contains more resin and as such will yield more product volume during
hydro cracking albeit more acidic. The differences in the components (viscosity, resin and asphaltenes
contents, sulphur and heavy metal contents) of the tar sands is within the limit of technology adaptation.
Any of the technologies used in Athabasca, Canada is adaptable to Nigeria according to the findings of this research.
The techno-economics of some of the process technologies are. x-rayed using the PTAC (petroleum
technology alliance Canada) technology recovery model in order to obtain their unit cost for Nigeria
bitumen. The unit cost of processed bitumen adopting steam assisted gravity drainage (SAGD), in situ
combustion (ISC) and cyclic steam stimulation (CSS) process technology is 40.59, 25.00 and 44.14
Canadian dollars respectively. The unit cost in Canada using the same process technology is 57.27, 25.00
and 61.33 Canadian dollars respectively. The unit cost in Nigeria is substantively lesser than in Canada.
A trade off is thereafter done using life cycle costing so as to select the best process technology for the
Nigeria oil/tar sands. The net present value/internal rate of return is found to be B$3,062/36.35% for
steam assisted gravity drainage, B$I,570124.51 % for cyclic steam stimulation and B$3,503/39.64% for in
situ combustion. Though in situ combustion returned the highest net present value and internal rate of
return, it proved not to be the best option for Nigeria due to environmental concern and response time to
production. The best viable option for the Nigeria tar sand was then deemed to be steam assisted gravity
drainage.
An integrated oil strategy coupled with cogeneration using MSAR was also seen to considerably amplify
the benefits accruable from bitumen exploration; therefore, an investment in bitumen exploration in
Nigeria is a wise economic decision. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2010.
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Modellierung bleibender Verformungen des Asphalts mit einem hypoplastischen Stoffgesetz der BodenmechanikGajári, György 31 January 2013 (has links) (PDF)
Die Arbeit dient der numerischen Simulation der Spurbildung in Asphaltstraßen und der Herstellung widerstandsfähiger Asphaltmischungen. Zur Modellbildung musste die physikalisch-mechanische Ursache der bleibenden Verformungen bei hohen Temperaturen geklärt werden. Im Gegensatz zu bisher existierenden Stoffmodellen ist in dieser Arbeit das Verhalten teilgesättigter granulerer Stoffe unter zyklischer Belastung als die Grundlage der Untersuchung gewählt worden. Diese zeigen bei entsprechend hoher Sättigung der Hohlräume des mineralischen Korngerüsts unter zyklischer Scherbeanspruchung und bei gleichzeitigem Druck das Phänomen der „zyklischen Mobilität”. Die Erklärung dafür ist die Verdichtungsneigung des Korngerüstes und die Inkompressibilität des Porenfluids, wodurch Porenüberdrücke entstehen. Zyklische Mobilität bedeutet den Abfall der Steifigkeit. Durch die Zunahme der Dehnungsamplituden infolge zyklischer Scherbelastung und der Irreversibilität des granularen Materials verursacht dieses Verhalten die erhöhte Spurbildungsneigung.
Die richtige Modellwahl konnte durch systematische experimentelle Ergebnisse belegt werden. Die monotonen triaxialen Kompressionsversuche beweisen die Barotropie und Pyknotropie der Steifigkeit, der Festigkeit und der Dilatanz des mineralischen Korngerüstes. Durch Kompression unter zyklischem Scheren wird die Existenz eines optimalen Bitumengehalts bewiesen, bei welchem die höchste Dichte des Kornegerüstes erreicht werden kann. Bei Mischungen über dem optimalen Bindemittelgehalt wird der Porenfluidüberdruck durch Druckmessungen im Mörtel nachgewiesen.
Für den Strassenbauasphalt ist erstmalig zur numerischen Simulation das aus Karlsruhe stammende, mit der „intergranularen Dehnung” erweiterte hypoplastische Stoffgesetz herangezogen worden. Den Schwerpunkt der Arbeit bildet die Bestimmung der hypoplastischen Stoffparameter und die Überprüfung des gewählten Stoffgesetzes durch Nachrechnung von zyklischen Einfachscherversuchen und Triaxialversuchen. In einer selbstentwickelten Torsionszelle wird durch unmittelbare Messung gezeigt, dass der Bitumengehalt über dem Optimum die Schubsteifigkeit verringert. Die Triaxialversuche beweisen die Möglichkeit des Eintretens der zyklischen Mobilität und dadurch die extreme Neigung zur Spurbildung. Diese Messungen beweisen die praktische Bedeutung des optimalen Bitumengehaltes. Das positive Ergebnis der Überprüfung des genanntes Stoffgesetzes liefert die theoretische Unterstützung der experimentellen Ergebnisse. Diese können als Grundlage einer neuen Perspektive in der rechnerischen Prognose sowie beim Entwurf und bei der Herstellung von Asphaltmischungen dienen.
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Mathematical and Statistical Investigation of Steamflooding in Naturally Fractured Carbonate Heavy Oil ReservoirsShafiei, Ali 25 March 2013 (has links)
A significant amount of Viscous Oil (e.g., heavy oil, extra heavy oil, and bitumen) is trapped in Naturally Fractured Carbonate Reservoirs also known as NFCRs. The word VO endowment in NFCRs is estimated at ~ 2 Trillion barrels mostly reported in Canada, the USA, Russia, and the Middle East. To date, contributions to the world daily oil production from this immense energy resource remains negligible mainly due to the lack of appropriate production technologies. Implementation of a VO production technology such as steam injection is expensive (high capital investment), time-consuming, and people-intensive. Hence, before selecting a production technology for detailed economic analysis, use of cursory or broad screening tools or guides is a convenient means of gaining a quick overview of the technical feasibility of the various possible production technologies applied to a particular reservoir. Technical screening tools are only available for the purpose of evaluation of the reservoir performance parameters in oil sands for various thermal VO exploitation technologies such as Steam Assisted Gravity Drainage (SAGD), Cyclic Steam Stimulation (CSS), Horizontal well Cyclic steam Stimulation (HCS), and so on. Nevertheless, such tools are not applicable for VO NFCRs assessment without considerable modifications due to the different nature of these two reservoir types (e.g., presence and effects of fracture network on reservoir behavior, wettability, lithology, fabric, pore structure, and so on) and also different mechanisms of energy and mass transport. Considering the lack of robust and rapid technical reservoir screening tools for the purpose of quick assessment and performance prediction for VO NFCRs under thermal stimulation (e.g., steamflooding), developing such fast and precise tools seems inevitable and desirable.
In this dissertation, an attempt was made to develop new screening tools for the purpose of reservoir performance prediction in VO NFCRs using all the field and laboratory available data on a particular thermal technology (vertical well steamflooding). Considering the complex and heterogeneous nature of the NFCRs, there is great uncertainty associated with the geological nature of the NFCRs such as fracture and porosity distribution in the reservoir which will affect any modeling tasks aiming at modeling of processes involved in thermal VO production from these types of technically difficult and economically unattractive reservoirs. Therefore, several modeling and analyses technqiues were used in order to understand the main parameters controlling the steamflooding process in NFCRs and also cope with the uncertainties associated with the nature of geologic, reservoir and fluid properties data. Thermal geomechanics effects are well-known in VO production from oil sands using thermal technologies such as SAGD and cyclic steam processes. Hence, possible impacts of thermal processes on VO NFCRs performance was studied despite the lack of adequate field data.
This dissertation makes the following contributions to the literature and the oil industry: Two new statistical correlations were developed, introduced, and examined which can be utilized for the purpose of estimation of Cumulative Steam to Oil Ratio (CSOR) and Recovery Factor (RF) as measures of process performance and technical viability during vertical well steamflooding in VO Naturally Fractured Carbonate Reservoirs (NFCRs). The proposed correlations include vital parameters such as in situ fluid and reservoir properties. The data used are taken from experimental studies and also field trials of vertical well steamflooding pilots in viscous oil NFCRs reported in the literature. The error percentage for the proposed correlations is < 10% for the worst case and contains fewer empirical constants compared with existing correlations for oil sands. The interactions between the parameters were also considered. The initial oil saturation and oil viscosity are the most important predictive factors. The proposed correlations successfully predicted steam/oil ratios and recovery factors in two heavy oil NFCRs. These correlations are reported for the first time in the literature for this type of VO reservoirs.
A 3-D mathematical model was developed, presented, and examined in this research work, investigating various parameters and mechanisms affecting VO recovery from NFCRs using vertical well steamflooding. The governing equations are written for the matrix and fractured medium, separately. Uncertainties associated with the shape factor for the communication between the matrix and fracture is eliminated through setting a continuity boundary condition at the interface. Using this boundary condition, the solution method employed differs from the most of the modeling simulations reported in the literature. A Newton-Raphson approach was also used for solving mass and energy balance equations. RF and CSOR were obtained as a function of steam injection rate and temperature and characteristics of the fractured media such as matrix size and permeability. The numerical solution clearly shows that fractures play an important role in better conduction of heat into the matrix part. It was also concluded that the matrix block size and total permeability are the most important parameters affecting the dependent variables involved in steamflooding.
A hybrid Artificial Neural Network model optimized by co-implementation of a Particle Swarm Optimization method (ANN-PSO) was developed, presented, and tested in this research work for the purpose of estimation of the CSOR and RF during vertical well steamflooding in VO NFCRs. The developed PSO-ANN model, conventional ANN models, and statistical correlations were examined using field data. Comparison of the predictions and field data implies superiority of the proposed PSO-ANN model with an absolute average error percentage < 6.5% , a determination coefficient (R2) > 0.98, and Mean Squared Error (MSE) < 0.06, a substantial improvement in comparison with conventional ANN model and empirical correlations for prediction of RF and CSOR. This indicates excellent potential for application of hybrid PSO-ANN models to screen VO NFCRs for steamflooding. This is the first time that the ANN technique has been applied for the purpose of performance prediction of steamflooding in VO NFCRs and also reported in the literature. The predictive PSO-ANN model and statistical correlations have strong potentials to be merged with heavy oil recovery modeling softwares available for thermal methods. This combination is expected to speed up their performance, reduce their uncertainty, and enhance their prediction and modeling capabilities.
An integrated geological-geophysical-geomechanical approach was designed, presented, and applied in the case of a NFCR for the purpose of fracture and in situ stresses characterization in NFCRs. The proposed methodology can be applied for fracture and in situ stresses characterization which is beneficial to various aspects of asset development such as well placement, drilling, production, thermal reservoir modeling incorporating geomechanics effects, technology assessment and so on. A conceptual study was also conducted on geomechanics effects in VO NFCRs during steamflooding which is not yet well understood and still requires further field, laboratory, and theoretical studies. This can be considered as a small step forward in this area identifying positive potential of such knowledge to the design of large scale thermal operations in VO NFCRs.
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Mathematical and Statistical Investigation of Steamflooding in Naturally Fractured Carbonate Heavy Oil ReservoirsShafiei, Ali 25 March 2013 (has links)
A significant amount of Viscous Oil (e.g., heavy oil, extra heavy oil, and bitumen) is trapped in Naturally Fractured Carbonate Reservoirs also known as NFCRs. The word VO endowment in NFCRs is estimated at ~ 2 Trillion barrels mostly reported in Canada, the USA, Russia, and the Middle East. To date, contributions to the world daily oil production from this immense energy resource remains negligible mainly due to the lack of appropriate production technologies. Implementation of a VO production technology such as steam injection is expensive (high capital investment), time-consuming, and people-intensive. Hence, before selecting a production technology for detailed economic analysis, use of cursory or broad screening tools or guides is a convenient means of gaining a quick overview of the technical feasibility of the various possible production technologies applied to a particular reservoir. Technical screening tools are only available for the purpose of evaluation of the reservoir performance parameters in oil sands for various thermal VO exploitation technologies such as Steam Assisted Gravity Drainage (SAGD), Cyclic Steam Stimulation (CSS), Horizontal well Cyclic steam Stimulation (HCS), and so on. Nevertheless, such tools are not applicable for VO NFCRs assessment without considerable modifications due to the different nature of these two reservoir types (e.g., presence and effects of fracture network on reservoir behavior, wettability, lithology, fabric, pore structure, and so on) and also different mechanisms of energy and mass transport. Considering the lack of robust and rapid technical reservoir screening tools for the purpose of quick assessment and performance prediction for VO NFCRs under thermal stimulation (e.g., steamflooding), developing such fast and precise tools seems inevitable and desirable.
In this dissertation, an attempt was made to develop new screening tools for the purpose of reservoir performance prediction in VO NFCRs using all the field and laboratory available data on a particular thermal technology (vertical well steamflooding). Considering the complex and heterogeneous nature of the NFCRs, there is great uncertainty associated with the geological nature of the NFCRs such as fracture and porosity distribution in the reservoir which will affect any modeling tasks aiming at modeling of processes involved in thermal VO production from these types of technically difficult and economically unattractive reservoirs. Therefore, several modeling and analyses technqiues were used in order to understand the main parameters controlling the steamflooding process in NFCRs and also cope with the uncertainties associated with the nature of geologic, reservoir and fluid properties data. Thermal geomechanics effects are well-known in VO production from oil sands using thermal technologies such as SAGD and cyclic steam processes. Hence, possible impacts of thermal processes on VO NFCRs performance was studied despite the lack of adequate field data.
This dissertation makes the following contributions to the literature and the oil industry: Two new statistical correlations were developed, introduced, and examined which can be utilized for the purpose of estimation of Cumulative Steam to Oil Ratio (CSOR) and Recovery Factor (RF) as measures of process performance and technical viability during vertical well steamflooding in VO Naturally Fractured Carbonate Reservoirs (NFCRs). The proposed correlations include vital parameters such as in situ fluid and reservoir properties. The data used are taken from experimental studies and also field trials of vertical well steamflooding pilots in viscous oil NFCRs reported in the literature. The error percentage for the proposed correlations is < 10% for the worst case and contains fewer empirical constants compared with existing correlations for oil sands. The interactions between the parameters were also considered. The initial oil saturation and oil viscosity are the most important predictive factors. The proposed correlations successfully predicted steam/oil ratios and recovery factors in two heavy oil NFCRs. These correlations are reported for the first time in the literature for this type of VO reservoirs.
A 3-D mathematical model was developed, presented, and examined in this research work, investigating various parameters and mechanisms affecting VO recovery from NFCRs using vertical well steamflooding. The governing equations are written for the matrix and fractured medium, separately. Uncertainties associated with the shape factor for the communication between the matrix and fracture is eliminated through setting a continuity boundary condition at the interface. Using this boundary condition, the solution method employed differs from the most of the modeling simulations reported in the literature. A Newton-Raphson approach was also used for solving mass and energy balance equations. RF and CSOR were obtained as a function of steam injection rate and temperature and characteristics of the fractured media such as matrix size and permeability. The numerical solution clearly shows that fractures play an important role in better conduction of heat into the matrix part. It was also concluded that the matrix block size and total permeability are the most important parameters affecting the dependent variables involved in steamflooding.
A hybrid Artificial Neural Network model optimized by co-implementation of a Particle Swarm Optimization method (ANN-PSO) was developed, presented, and tested in this research work for the purpose of estimation of the CSOR and RF during vertical well steamflooding in VO NFCRs. The developed PSO-ANN model, conventional ANN models, and statistical correlations were examined using field data. Comparison of the predictions and field data implies superiority of the proposed PSO-ANN model with an absolute average error percentage < 6.5% , a determination coefficient (R2) > 0.98, and Mean Squared Error (MSE) < 0.06, a substantial improvement in comparison with conventional ANN model and empirical correlations for prediction of RF and CSOR. This indicates excellent potential for application of hybrid PSO-ANN models to screen VO NFCRs for steamflooding. This is the first time that the ANN technique has been applied for the purpose of performance prediction of steamflooding in VO NFCRs and also reported in the literature. The predictive PSO-ANN model and statistical correlations have strong potentials to be merged with heavy oil recovery modeling softwares available for thermal methods. This combination is expected to speed up their performance, reduce their uncertainty, and enhance their prediction and modeling capabilities.
An integrated geological-geophysical-geomechanical approach was designed, presented, and applied in the case of a NFCR for the purpose of fracture and in situ stresses characterization in NFCRs. The proposed methodology can be applied for fracture and in situ stresses characterization which is beneficial to various aspects of asset development such as well placement, drilling, production, thermal reservoir modeling incorporating geomechanics effects, technology assessment and so on. A conceptual study was also conducted on geomechanics effects in VO NFCRs during steamflooding which is not yet well understood and still requires further field, laboratory, and theoretical studies. This can be considered as a small step forward in this area identifying positive potential of such knowledge to the design of large scale thermal operations in VO NFCRs.
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Rendre possible un espace intermédiaire de dialogue pour coconstruire de nouvelles solutions de prévention dans un contexte d’incertitude : cas des travaux de revêtements routiers / To made possible an intermediate space for dialogue to co-construct new prevention solutions in a context of uncertainly : Case of road surfacing worksJudon, Nathalie 19 October 2017 (has links)
Dans le contexte d’incertitude actuel entourant la problématique de l’exposition au bitume dans les travaux de revêtement routier, la thèse vise l’élaboration de principes généraux et de méthodes d’action pour des solutions préventives nouvelles permettant d’enrichir les dispositifs de prévention existants. Dans cette perspective, nous avons développé une démarche centrée sur l’association des travailleurs de tout niveau hiérarchique (opérateurs, encadrement de proximité, préventeurs et décideurs) autour « d’objets intermédiaires de prévention » afin de soutenir un débat collectif. Ce débat collectif est envisagé comme une pratique réflexive sur l’activité de travail, elle-même considérée comme la condition d’un langage commun, permettant de changer des choix initiaux et constituant une ressource pour les apprentissages mutuels entre acteurs. Pour cela, nous avons développé, repris et enrichi la notion de représentation des risques qui favorise la mise en visibilité et la reconnaissance des savoirs construits, développés et portés par les travailleurs sur leur activité et sur les façons de se protéger des dangers. Ces représentations du risque et ces savoir-faire sont un élément déterminant de la prévention car ils s’exercent à la fois dans des modes normaux et dégradés de l’activité et sont issus de l’expérience et d’une construction sociale. Nous avons développé une connaissance précise de l’activité des opérateurs de mise en oeuvre d’enrobés dans deux agences de travaux publics, qui a mis en évidence que les acteurs de terrain possèdent des connaissances fines sur les risques chimiques. Ces représentations, essentiellement permises par l’expérience du corps et des sens, ne sont pas toujours convocables pour mettre en oeuvre des activités de protection dans l’activité de travail. Elles seraient empêchées voire « enkystées » quand il semble impossible aux travailleurs de faire autrement avec la nécessité de gérer aléas, variabilités et autres dangers présents et quand leur pouvoir d’agir leur apparait comme inexistant. Pourtant, nous montrons qu’elles deviennent accessibles à partir de références à la sphère intime et domestique dans des activités réflexives qui mobilisent à la fois des données d’observations, de mesures et des verbalisations. Dans une perspective de recherche en prévention, l’objet de la thèse est alors d’établir un dialogue entre différents mondes, institutionnels et de l’entreprise, afin de permettre aux acteurs de s’investir et de mobiliser leurs ressources individuelles, collectives et organisationnelles pour proposer des solutions de prévention. Cet « espace intermédiaire de dialogue » est rendu possible par la co-construction d’objets intermédiaires en capacité 1- de produire et soutenir un débat autour des pratiques effectives des opérateurs et de leurs représentations au regard des dispositifs de sécurité existants et 2- d’être support aux dialogues et aux apprentissages mutuels. Ces objets intermédiaires de prévention sont in fine des entités circulantes pour la coproduction d’un savoir pour l’action : produire des connaissances et générer collectivement des solutions innovantes de prévention. / In the context of current uncertainty surrounding the problem of exposure to bitumen in road surfacing (coating), the aim of the thesis is to set up general principles and methods of action for new preventive solutions that will enrich the existing measures. In this perspective, we have developed an approach centred on the association of workers at all hierarchical levels (operators, proximity managers, prevention workers and decision-makers) around "intermediary objects of prevention" in order to support a collective debate. This collective debate is seen as a reflective practice on work activity, which is itself seen as the condition of a common language, allowing for initial choices to be changed and a resource for mutual learning between actors. To this end, we have developed, reworked and enriched the notion of risk representation, which promotes the visibility and recognition of the knowledge built, developed and carried by workers on their activities and on ways to protect themselves from dangers or hazards. These representations of risk and the know-hows are a decisive element of prevention because they are applied in both normal and degraded modes of the activity and are derived from experience and social construction. We have developed a fine and precise knowledge of the activity of asphalt processing operators in two public works agencies, which highlighted that the players in the field have a detailed knowledge of chemical risks. These representations, which were essentially made possible by the experience of the body and the senses, cannot always been called up with a view to setting up protective measures in the work activity. They would be prevented or even "encysted" when it seems impossible for workers to do otherwise with the need to manage the hazards, variability and other dangers present and when their power to act seems to them to be non existent. And yet, we show that they become accessible from references to the intimate and domestic sphere in reflexive activities that mobilize both data from observations, measurements and verbalizations. From a preventive research perspective, the aim of the thesis is to establish a dialogue between different institutional and corporate worlds so as to enable the actors to get involved and mobilize their individual, collective and organizational resources to propose prevention solutions. This "intermediate space for dialogue" is made possible by the coconstruction of intermediate objects capable of 1- producing and supporting a debate about the current practices of the operators and their representations with regard to the existing safety devices and 2- supporting dialogues and mutual learning. These intermediate prevention objects are ultimately circulating entities for the co-production of knowledge for action: to generate knowledge and to collectively generate innovative prevention solutions.
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Navrhování nízkohlučných asfaltových směsí / Design of low-noise asphalt mixturesŘehulka, Martin January 2020 (has links)
The Master’s thesis is focused on low-noise asphalt mixtures in general, namely asphalt concrete for very thin layers with low noise (BBTM 8 NH) and stone mastic asphalt with low noise (SMA 8 NH). The first half of the thesis describes basic types of asphalt mixtures with low noise, requirements for raw materials (aggregates and asphalt), noise emissions and their measurement methods. The second part deals the design of BBTM 8 NH and SMA 8 NH so that they have the same voids. Subsequently, their parameters were tested. Acoustic absorption, resistence against permanent deformation and stiffness. Test methods are described and evaluated.
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Návrh asfaltových směsí typu SAL určených pro opravu cementobetonových krytů / Design of SAL asphalt mixtures for rehabilitation of concrete pavementsVlk, Radomír January 2015 (has links)
This master's thesis describes how to use the asphalt layer called Stress Absorbing Layer (SAL) and comparises it with other types of SAL with different types of asphalt binders. In the first theoretical part is SAL generally described. In the second part is SAL practically tested and described.
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