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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

ESTUDO DE TIPOLOGIAS DE LAJES QUANTO AO ISOLAMENTO AO RUÍDO DE IMPACTO / STUDY OF TYPOLOGIES OF FLOOR-SUPPORT IN REGARD TO ISOLATION OF NOISE IMPACT

Pereyron, Daniel 24 October 2008 (has links)
The current research focuses on the environmental comfort in the civil construction and refers to a comparative analysis related to the acoustic isolation of reinforced concrete pavement which is submitted to noise of impact. According to thestandards ISO-140/VII, the measurements were taken in situ by using appropriate equipment for this purpose. In order to achieve the aims of this dissertation, unfinished constructions which used different typologies of floor-support (slab) in their structural system were chosen as the object of measurement and, this way, uncovered slabs could be measured. Therefore a better evaluation of their performance was possible and the sound isolation was related to the impact noise, providing evidence of the acoustic isolation. The analysis and interpretation of the results were undertaken through tables and graphs that, according to ISO 717-2, show the performance of each slab and a possible comparison among them. This is also a contributing factor to civil construction professionals as being a working instrument and it serves as a data base for a better understanding towards these materials performance. In this way, minimal values of acoustic comfort may be estimated in a near future. / A presente pesquisa concentra-se na área de conforto ambiental na construção civil e refere-se a uma análise comparativa quanto ao desempenho do isolamento acústico de tipologias de lajes submetidas a ruído de impacto. Os ensaios foram realizados in situ , em conformidade com as normas da ISO-140/VII, utilizando equipamentos adequados para este fim. Para o desenvolvimento desta dissertação, escolheram-se como objetos de medição obras ainda em fase de construção que tivessem utilizado como sistema estrutural as lajes maciça, nervurada, pré-moldada convencional e pré-moldada treliçada, possibilitando assim a medição das lajes em osso , ou seja, sem o revestimento de piso. Dessa forma, foi permitida uma melhor avaliação do desempenho dessas, relacionando o isolamento sonoro ao ruído de impacto, evidenciando assim o desempenho acústico deste sistema. A análise e interpretação dos resultados foram realizadas através de tabelas e gráficos que, de acordo com a ISO 717-2, demonstram o desempenho de cada laje, permitindo-nos assim traçar um comparativo entre essas, o que contribui como ferramenta de trabalho para os profissionais da construção civil e serve como base de dados para um melhor conhecimento do desempenho destes materiais. Desse modo, valores mínimos de conforto acústico ao usuário da construção civil podem vir a serem traçados futuramente.
22

Lávka pro pěší / Footbridge

Londa, Jan January 2019 (has links)
The diploma thesis deals with design and assessment of pedestrian and bicycle footbridges across the river Moravia in Olomouc. The main material used in the design is S355 steel. At the beginning of the thesis, two variants are compared, from which one is subsequently selected for a more detailed design and assessment. The main supporting element of the selected variant are two parabolic arcs inclined to one another, on which the coupling of the intermediate bridge is suspended by means of the rods. The construction span is 54m.
23

Nonlinear FEM load bearing capacity assessment of a concrete bridge subjected to support settlements : Case of a continious slab bridge with angled supports

Hansson, Daniel January 2013 (has links)
A nonlinear finite element analysis was performed for an existing road bridge in order to see if that could show a higher load bearing capacity, as an alternative to repairing or replacing. The regular linear analysis had shown that the bridge could not take any traffic load due to the effects from large and uneven support settlements. It is a five-span reinforced concrete bridge with a continuous slab on supports made out of rows of columns. The width-to-span ratio was around 1 and the supports were angled up to about 30°, giving rise to a complex three-dimensional behaviour, which was seen and studied in the nonlinear results. Since the bending moment was the limiting factor, the nonlinear analysis focused on that. The direct result was that the load bearing capacity was 730 kN for the traffic vehicle boogie load, B, in the ultimate limit state. This was however only for the load case tested, and several more disadvantageous vehicle positions may exist. Other aspects also became limiting, as the maximum allowed vertical deflection in the serviceability limit state was reached at 457 kN. The most restraining though, was the shear capacity from the linear analysis; 78 kN, since it was not possible to simulate that type of failure with the shell elements used in the nonlinear finite element analysis. The main aim of the thesis was nonetheless reached, since the nonlinear analysis was able to show a significant increase in load bearing capacity.  A comparison was made with the settlements for the nonlinear case, to see how much influence they had on the load bearing capacity for traffic load. This was performed for both the bridge and a simple two-span beam. Both showed that there was no effect on the load bearing capacity in the ultimate limit. One thing to note was that the full settlements were applied, and with no relaxation due to creep.  Another aim of the thesis was to make comments on the practical usability of the nonlinear finite element method in load bearing capacity assessments. A linear analysis was performed before the nonlinear in order to be able to determine the load case to be used in the latter. This worked well, as the strengths of the two methods could then be utilized. Convergence problems were however encountered for the nonlinear when using the regular static solver. Due to this, the dynamic explicit calculation scheme was used instead, treating the case as quasi-static. This managed to produce enough usable results. It was concluded that the nonlinear finite element method is useable for assessment calculations, but that its strengths and weaknesses must be known in order to make it an efficient method.
24

Nosná železobetonová konstrukce vícepodlažního obytného objektu / Load-bearing reinforced concrete structure of a multi-storey residential building

Badány, Kristián January 2022 (has links)
The objective of the diploma thesis is a design and check of load-bearing concrete structure of multi-storey residential building. The building is located in Brno. The total ground plan’s dimensions are 39,32 x 22,58 metres, total height of the building in the highest point is 10,29 metres. The object is three-storey building with rectangular plan with partial basement designed as cast-in-place concrete frame and two above-ground floor designed as reinforced concrete walls and masonry walls. Load-bearing floor structures are designed as reinforced concrete slabs. Drawing documentation is included.
25

Nonlinear FEM load bearing capacity of a concrete bridge subjected to support settlements : Case of a continuous slab bridge with angled supports

Hansson, Daniel January 2013 (has links)
A nonlinear finite element analysis was performed for an existing road bridge in order to see if that could show a higher load bearing capacity, as an alternative to repairing or replacing. The regular linear analysis had shown that the bridge could not take any traffic load due to the effects from large and uneven support settlements. It is a five-span reinforced concrete bridge with a continuous slab on supports made out of rows of columns. The width-to-span ratio was around 1 and the supports were angled up to about 30°, giving rise to a complex three-dimensional behaviour, which was seen and studied in the nonlinear results. Since the bending moment was the limiting factor, the nonlinear analysis focused on that. The direct result was that the load bearing capacity was 730 kN for the traffic vehicle boogie load, B, in the ultimate limit state. This was however only for the load case tested, and several more disadvantageous vehicle positions may exist. Other aspects also became limiting, as the maximum allowed vertical deflection in the serviceability limit state was reached at 457 kN. The most restraining though, was the shear capacity from the linear analysis; 78 kN, since it was not possible to simulate that type of failure with the shell elements used in the nonlinear finite element analysis. The main aim of the thesis was nonetheless reached, since the nonlinear analysis was able to show a significant increase in load bearing capacity. A comparison was made with the settlements for the nonlinear case, to see how much influence they had on the load bearing capacity for traffic load. This was performed for both the bridge and a simple two-span beam. Both showed that there was no effect on the load bearing capacity in the ultimate limit. One thing to note was that the full settlements were applied, and with no relaxation due to creep. Another aim of the thesis was to make comments on the practical usability of the nonlinear finite element method in load bearing capacity assessments. A linear analysis was performed before the nonlinear in order to be able to determine the load case to be used in the latter. This worked well, as the strengths of the two methods could then be utilized. Convergence problems were however encountered for the nonlinear when using the regular static solver. Due to this, the dynamic explicit calculation scheme was used instead, treating the case as quasi-static. This managed to produce enough usable results. It was concluded that the nonlinear finite element method is useable for assessment calculations, but that its strengths and weaknesses must be known in order to make it an efficient method.
26

Projektering av en parkourbyggnad med förstärkning vid öppning i betongbjälklag / Designing of a building intended for parkour with a strengthened floor opening

Mickus, Deividas, Grujcic, Stefan January 2021 (has links)
Parkour är i grunden en konstform som kan utövas i olika miljöer oavsett om det är på enparkouranläggning eller på offentliga platser. Att utföra parkour är konsten att hitta och använda föremålsom hinder eller hjälpmedel för träning och för att utveckla rörelser. Aktiviteten går ut på ta sig frånpunkt A till punkt B på det snabbaste, smidigaste och effektivaste sättet. Bortsett från att parkour idaganses som en laglig idrottslig aktivitet anses den fortfarande som en typ av vandalism. Vad kan det beropå? Det beror främst på att en del parkourister väljer att utföra parkour på offentliga platser istället förspecifikt anpassade platser. Vad är anledningen att välja offentliga platser? Problemet att utföra parkour på specifikt anpassade platser är att de antingen inte är anpassade till enstörre målgrupp eller så är de ensidiga och saknar variation. Med det sagt begränsas aktiviteten till attendast enstaka förmågor kan testas. Projektering av en tvåplans parkourbyggnad i betong med öppningi bjälklaget är ytterligare ett sätt att testa en förmåga inom aktiviteten. Att utföra en sådan byggnad medrätt redskap, utformning och konstruktionslösningar krävde därför vägledning från en arkitekt och enkonstruktör. I rapporten redovisas olika typer av stomplan och studier bakom förstärkningsåtgärder vid öppning ibjälklag, för att besvara frågan: hur kan en öppning förstärkas om den saknar stöd i närheten? Val avstomplan och förstärkningsmetod har tagit hänsyn till dimensionering för böjande moment, men ävenatt projektet handlar om nyproduktion och estetiska aspekter som examensarbetet grundar sig på. Äventekniska och ekonomiska synpunkter är avgörande faktorer för valet. Tre stomplaner analyserades, men endast en stomplan valdes ut för vidare undersökning. Underarbetsgången behandlas olika förstärkningsmetoder som förstärkning med krage i form av armering ochförstärkning för fri kant. Förutom studie av förstärkningsmetoder dimensionerades betongplattan i olikatjocklekar med hänsyn till armeringsbehov. Rapporten grundades på ett finita elementprogram, FEM-Design 3D Structure, som användes förframtagning av moment och tvärkraft för olika modeller. För att underlätta arbetet gjordes ett flertalförenklingar som raka väggar vid hörn, hålet betraktas som rektangulärt, hinder/väggar på plattantolkades som laster m.m. Målet med förenklingar var att minska felmarginal som uppkommer i finitaelementmodell som sedan påverkar resultatet. Den slutsats som kan dras från resultat i FEM-Design, var att öppningen sänkte moment i plattan. Detberodde på att med en projekterad öppning kunde plattan delas upp i två mindre spännvidder. Vidareeftersträvades en förstärkningsåtgärd som inriktas till att förstyva plattan vid de kritiska områden ochsamtidigt uppfylla kraven som examensarbetet grundar sig på. Resultatet visade att det går åt mindrearmering för att öka momentkapacitet än för att minska på dimensionerande moment. Det betyder attdet blir mer ekonomiskt att åstadkomma en högre bärförmåga genom att höja momentkapaciteten än attminska dimensionerande moment med olika förstärkningsmetoder. Det som uppvisade bäst resultat var“stomplan 2” och användning av finita elementstorlek 0,15 m. Med analys av armering m.h.t. plattansolika tjocklekar kunde tjockleken 325 mm säkerställas och valet av 300 mm med förstärkning för frikant kunde visas som det bästa alternativet av de undersökta plattorna. / In general parkour is a form of art that can be performed in many different locations such as parkourparks or public places. The art of parkour is to find and use different objects as obstacles or as asupplement for training and development of different moves. Despite the fact that parkour is a legalactivity, it is still considered to be a type of vandalism. What is the reason for that? It is due to the factthat practitioners of parkour prefer to exercise in public places rather than limiting themselves inspecifically designed ones. Why do practitioners opt for exercising in public places? Firstly, the problem with those places is that they are not adapted for adults or they are ill-equipped andlack variation. Therefore, an activity gets limited because only a few abilities can be worked on.Designing a two-story concrete building intended for parkour with a floor opening is another way totest ability to parkour. In order to design that kind of building with the right appliance, shape andconstructive solutions, assistance from an architect and a constructor is required. This report shows different types of frameworks and studies behind strengthening solutions for a flooropening to find an answer for the following question: how can a floor opening be strengthened withouthaving the support for it in close proximity? Decisions of the framework and strengthening method areprimarily considered by bending moment, but also new productions and aesthetics of the building, whatthis dissertation is based on. The technical and economical aspects are also important for this decision. Three frameworks are analyzed, however only one of them will be chosen for further analysis. Theworking process shows various strengthening methods, for example strengthening by reinforcing theshape of the collar and strengthening the free edges. In addition to the study of strengthening methodsfor the floor opening, the concrete slab is analyzed in different thicknesses by considering the need ofthe reinforcements. The design is based on a finite element software FEM-Design 3D Structure that was used for calculationof moment and shear forces. Some simplifications were made to lighten the work. For example, straightwalls in the corners, floor opening was considered as a square, obstacles/walls on the slab wereinterpreted as a load, and many more. The aim of the simplifications is to reduce the room for errors inthe finite element model which has a potential to affect the results later on. The conclusion on the outcome of the models in FEM-design was that the opening reduces moment inthe slab. As a result of a projected opening, the slab was separated into two smaller spans. It furtherrequired a strengthening method to increase stiffness in the critical area and at the same time archivethe criterium for this dissertation. The results have shown that it requires less reinforcement byincreasing moment of resistance than reducing dimensioning moment on slab. That means that it ismore economical to increase the moment of resistance than to increase stiffness around opening withdifferent strengthening methods. Framework No.2 and usage of mesh size 0,15 m have shown the bestresults in this report. Analysis of reinforcement based on slab thickness gave a result of 325 mm whichled to a choice of slab 300 mm with reinforcement for free edges as the best alternative.
27

Increased Traffic Loads on Swedish Highway Bridges : A Case study of the bridge at highway interchange Värö

Forsberg, Fredrik January 2017 (has links)
The Swedish government is planning to increase the maximum vehicle gross load regulations on parts of the national roads from the present 60 t, for the load carrying capacity class BK1, to 74 t, for the proposed new load carrying capacity class BK4. The initial implementation of the new load carrying capacity class for 74 t vehicles will only regard major highways and important roads, however, at a later stage the plan is to implement the new BK4 class on the full current BK1 road network. The biggest obstacle which arises when implementing these increased traffic loads is insufficient load carrying capacity for the bridges on the road network.   Thus, the objective of this thesis is to examine and analyze the effects of the increased traffic loads on Swedish road bridges. In order to identify the structural effects of the load increase, and draw general conclusions regarding the effects on the bridge network as a whole, a case study with load carrying capacity calculations is carried out on a two-span concrete slab fram bridge at a highway interchange in Värö in western Sweden. The bridge is classified as critical by Trafikverket. The load carrying capacity calculation is carried out using the Swedish standards, in which maximum load values for the axle load, A, and the bogie load, B, is calculated.   The load effects acting on the bridge are calculated using the finite element software BRIGADE/Standard, with input traffic A and B loads amounting to 12 t and 21 t respectively for the new BK4 class and to 12 t and 18 t respectively for class BK1. In addition to the load carrying capacity calculations with BK4 traffic loads, a comparison is carried out between the results obtained when using the axle- and bogie loads from the BK1 versus the BK4 load carrying capacity class in the load carrying capacity calculations.   The load carrying capacity calculations performed on the studied bridge shows that the capacity of the bridge, both in regards to moment and shear force, is insufficient to meet the new, increased, BK4 A/B – requirements. The critical A/B – values for the whole bridge are 17 t and 18 t respectively, to be compared with the required 12- and 21 t limit for the new BK4 load carrying capacity class, thus, making the load carrying capacity of the bridge inadequate. The critical A/B – values appear for the longitudinal shear force load case at the point where the shear force reinforcement over the column support ends. Moreover, the difference between the results obtained when using the BK1 versus the BK4 traffic loads in the calculations were found to be negligible.   Due to the differing properties and characteristics of each individual bridge on the Swedish road network it is difficult to make general statements regarding the effects of the increased traffic loads on the bridge network as a whole. Specific load carrying capacity calculations will need to be performed on each individual bridge in order to evaluate its capability to withstand the new increased BK4 traffic load. However, capacity calculations regarding the BK1 load carrying capacity class can, with sufficient accuracy, be used to evaluate the capability of a bridge to withstand the increased traffic loads in the BK4 load carrying capacity class, thus, making it easier to evaluate the strengthening needs for the bridge network as a whole. / Sveriges regering planerar en utökning av den maximalt tillåtna bruttovikten för fordon på delar av det allmänna vägnätet från den nuvarande begränsningen på 60 t, för bärighetsklass BK1, till 74 t, för den nya föreslagna bärighetsklassen BK4. I det första skedet kommer den nya bärighetsklassen, för fordon med bruttovikt upp till 74 t, bara att implementeras på stora motorvägar och andra ur transportsynpunkt viktiga vägar, men, i ett senare skede finns också planer på att implementera den nya bärighetsklassen, BK4, på hela det nuvarande BK1 vägnätet. Det största problemet som förväntas uppkomma under införandet av de nya, ökade, trafiklasterna är otillräcklig bärighet på vägnätets broar.   Således är målet med denna uppsats att undersöka och analysera effekterna av dessa ökade trafiklaster för broar på det Svenska vägnätet. För att identifiera effekterna, och dra generella slutsatser, gällande denna ökade trafiklast för broarna på det Svenska vägnätet i sin helhet kommer en fallstudie med bärighetsberäkningar utföras på en plattrambro vid trafikplats Värö - en bro som Trafikverket bedömer som kritisk. Bärighetsberäkningen utförs enligt svenska standarder, där maximala tillåtna värden på axellasten, A, och bogielasten, B, beräknas.   Lasteffekterna som verkar på bron beräknas med hjälp finita element programvaran BRIGADE/Standard med trafiklaster, A och B, som uppgår till 12  respektive 21 t för den nya BK4 bärighetsklassen och 12 respektive 18 t för bärighetsklass BK1. Som tillägg till bärighetsberäkningarna med BK4 laster utförs också en jämförelse av resultaten som uppkommer när axel- och bogielasterna från BK1 respektive BK4 används i beräkningarna.    Bärighetsberäkningarna på den studerade bron visar att brons kapacitet, både gällande moment och tvärkraft, är otillräcklig när den belastas med de ökade BK4 trafiklasterna. De kritiska A- och B- värdena för bron är 17 respektive 18 t, värden som skall jämföras med kraven på 12 respektive 21 t för den nya bärighetsklassen BK4 – därmed är brons bärighet otillräcklig. De kritiska A- och B-värdena för bron uppkommer för lastfallet med longitudinell tvärkraft vid punkten där tvärkraftsarmeringen över mittstödet slutar verka. Jämförelsen mellan beräkningsresultaten som uppkom med trafiklaster enligt BK1 respektive BK4 visade att skillnaden mellan beräkningsresultaten var försumbar.   På grund av de varierande egenskaperna hos varje enskild bro på det Svenska vägnätet är det svårt att dra generella slutsatser gällande effekterna av lastökningen för vägnätet som helhet. Specifika bärighetsberäkningar måste utföras på varje individuell bro för att kunna utvärdera dess kapacitet att klara av de nya, ökade, BK4 trafiklasterna. Emellertid kan bärighetsberäkningar som beträffar bärighetsklassen BK1, med tillräcklig tillförlitlighet, användas för att bedöma en bros möjlighet att motstå de ökade trafiklasterna i den nya bärighetsklassen BK4, vilket förenklar utvärderingen av vilka broar som kräver förstärkning.
28

Statická analýza konstrukce pro zpracování odpadu / Static Analysis of Waste Treatment Plant Structure

Luliak, Ondřej January 2015 (has links)
Master thesis deals with static analysis of construction of hall type for waste treatment. Thesis includes design and structural assessment of main support elements of construction. This is two-aisled combined skeleton object. The roof system is composed of steel truss structure.
29

Bjälklag i Betong är billigare än Korslimmat trä : en jämförelse mellan bjälklagskonstruktioner

Kareliusson, Filip, Lipecki, Thomas January 2017 (has links)
Byggnadstaktenav flerbostadshus i Sverige ligger på en hög nivå och ökar. Detta medför kravpå en snabb byggprocess. En lösning för att snabba på byggprocessen äranvändandet av prefabricerade delar. Författarnas uppgift, i samarbete med WSPSverige AB, är att utveckla ett hjälpmedel för konstruktörer som jämför fyraolika bjälklag, varav ett i korslimmat trä, två prefabricerade betongelementoch en platsgjuten konstruktion. Målet är att framställa en tabell som beaktarfaktorer som påverkar valet av stomsystem och som presenterar vilket avbjälklagen som är mest kostnadseffektivt. Rapporten sammanställdes under 10veckor och avgränsades till bjälklag i flerbostadshus upplagda på två stöd somuppfyller relevanta krav för dimensionering, beaktar torktid med fastaförutsättningar, leveranstid avseende produktionstid hos de prefabriceradeelementen och miljöpåverkan avseende CO2-ekvivalenta utsläpp iproduktionsskedet. Studiens resultat grundar sig på litteraturstudier ochintervjuer, kalkylhjälpmedel och beräkningsprogram som är vanliga i branschen.Resultatet visar att: · trä genererar lägst koldioxidutsläpp avbjälklagsalternativen · betong är, ur ett brand- och ljudperspektiv, detlämpligaste materialet · korslimmade träbjälklaget får den högsta byggnadshöjdenoch den högsta kostnaden per kvadratmeter · håldäcksbjälklag har den kortaste leveranstiden · det slakarmerade plattbärlag samt det platsgjutnabetongbjälklaget har längst torktid · den platsgjutna bjälklagskonstruktionen är detmest kostnadseffektiva bjälklaget av de fyra som har jämförts. / The building pace of multi apartment houses in Sweden is at a high leveland is increasing. This induces demands of a quick building process. Onesolution to quicken the building process is the use of prefabricated elements.The authors’ task, in collaboration with WSP Sverige AB, is to develop anaiding tool for engineers who compare different slabs, one cross laminatedwood, two precast concrete components and one construction cast in-place. Thegoal is to produce a table that considers factors that affects the choice ofstructure and presents which of the slabs that is most cost effective. Thepaper was compiled over a period of 10 weeks and limited to slabs inmulti-apartment buildings supported on two sides that meet relevantrequirements for dimensioning, consider hydration time with set conditions,delivery time regarding production time for the precast components andenvironmental effects considering CO2-equivalent emissions in the productionstage. The results of the study are founded on literature and interviews,calculation-aids and computational programs that are common in the industry.The outcome shows that: · woodgenerates the least amount of carbondioxide emissions of the slab alternatives · concrete is, from a fire- and acoustic perspective, the most suitable material · thecross laminated slab renders the highest cross-section and the highest cost persquare meter · hollow core slabs has the shortest delivery time · theconventionally reinforced precast slabs and the in-situ cast floor slabs havethe longest hydration times · thein situ slab is the most cost effective slab of the four that have beencompared. / <p>Betyg 170707, H14.</p>
30

Transfert d'un composé organo-chloré depuis une zone source localisée en zone non saturée d'un aquifère poreux vers l'interface sol-air : expérimentations et modélisations associées / Transfer of an organo-chlorinated compound from a source area located in the unsaturated zone of a porous aquifer to the soil-air interface : experiments and modelling related

Marzougui Jaafar, Salsabil 29 January 2013 (has links)
Deux expériences ont été menées sur la plate-forme expérimentale "SCERES" afin d'évaluer les concentrations et les flux de vapeurs de TCE dans SCERES en présence de deux dalles de béton fissurées installées, l'une après l'autre, à la surface de SCERES. Cet aquifère poreux est un milieu hétérogène de grande échelle (25 x 12 x 3 m3). Les résultats ont montré que le panache de vapeur de TCE couvre la plupart du bassin au bout de 3 semaines depuis la création de la zone source de TCE dans le sous sol. L'hétérogénéité du site SCERES a engendrée une distribution verticale non uniforme de la concentration de vapeurs de TCE. La simulation du panache de vapeur dans SCERES a été effectuée au moyen du code de calcul multiphasique "SIMUSCOPP". La présence sur SCERES de la dalle de béton, un milieu peu perméable et peu diffusif, a constitué une "barrière" en vue du transfert de vapeurs de TCE vers l'interface dalle/atmosphère. Afin de mieux quantifier le flux de vapeurs à travers la dalle de béton, une étude de coefficient de diffusion et de perméabilité des deux dalles a été réalisée. Un mouvement vertical ascendant du toit de la nappe a généré un fort gradient de pression motrice de l'air du sol. Ceci a engendré une forte augmentation des flux de vapeurs à l'interface sol/atmosphère. La quantification de ces flux de vapeurs a été effectuée à l'aide d'une solution semi analytique basée sur la loi de Fick et la loi de Darcy en tenant compte à la fois de l'effet de gradient de pression motrice et l'effet de densité de vapeurs sur le transfert de vapeurs vers la surface du sol. L'intrusion de vapeurs de TCE dans le bâtiment modèle, installé sur la dalle de béton, a été générée par une mise en dépression dans ce dernier. Ce qui a fait augmenter la concentration de vapeurs de TCE sous la dalle ainsi dans le bâtiment. La simulation de l'intrusion de vapeurs dans l'air intérieur de bâtiment a été réalisée par l'intermédiaire du code de calcul multiphysics "COMSOL", avec lequel nous avons démontré l'évolution de la concentration de vapeurs obtenues expérimentalement dans le bâtiment et qui dépend directement de la variation spatio-temporelle du flux massique à travers la dalle. / Two experiments were conducted on the experimental platform "SCERES" to assess the TCE vapour concentrations and fluxes in SCERES with two concrete slabs installed, one after the other, on the ground surface. This artificial aquifer is a large scale (25 x 12 x 3 m3) heterogeneous porous medium. The results showed that the TCE vapour plume covers most of the basin 3 weeks after the creation of the TCE source area in unsaturated zone. The heterogeneity of SCERES has generated a non uniform vertical distribution of the TCE vapour concentration. Simulation of vapour plume in SCERES was carried out by the multiphase code "SIMUSCOPP".The presence in SCERES of a low permeability and low diffusive medium compared to the sand in the basin,as a concrete slab, constituted a "barrier" for the transfer of TCE vapour to the interface concrete slab / atmosphere. To better quantify the TOE fluxes through the concrete slab, a study of diffusion coefficient and permeability of both concrete slabs was done. An upward vertical movement of the water table has generated a strong soil air pressure driving gradient, which led to a strong increase in the TCE vapour concentrations near the surface which has increased the vapour fluxes at the interface soil / atmosphere. Quantification of vapour fluxes at the interfaces soil / atmosphere and concrete slab / atmosphere was performed using a semi analytical approach based onFick's and Darcy's laws by taking into account both the effect of the driving pressure gradient and the effect of density vapour on the vapour transfer towards the soil surface.The intrusion of TCE vapours into the model building installed on the concrete slab was generated by creating a vacuum. The results showed that, during the TCE vapour suction from the model building, the concentration of TCE vapours under the concrete slab and in the building increases. Simulation of vapour intrusion into indoor air was done by the computational Multiphysics code "COMSOL", allowing simulation of the evolution of the vapour concentration obtained experimentally in the building. Il was shown that they depend directly on the spatial-temporal variation of the mass flux through the slab.

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