No / Porous road surfaces offer an effective means of reducing the generation and propagation of noise from road traffic. However, the porosity of these surfaces can deteriorate over time, leading to a reduction in their noise reducing properties. Efficient methods are therefore required for monitoring this performance. Existing techniques for performing in-situ measurements of acoustic absorption are unsuitable for use within the traffic stream. Static measurements using time domain Maximum Length Sequence (MLS) based techniques have been demonstrated to offer advantages over traditional techniques, presenting the opportunity for measurements under dynamic conditions. This paper describes the design of a system for carrying out dynamic MLS-based measurements. Results are presented which demonstrate that stable dynamic measurements can be carried out at speeds of up to 30 km/h.

<p>Nowadays, NRTS (Nighttime Road Traffic Safety) and energy saving are very hot topics in transportation field. This thesis investigates a general optimal model for minimizing NRTAs (nighttime road traffic accidents) and power consumption of the road lighting. To establish this model, the relationship between N/D RTAs (Night to Day Road Traffic Accidents) ratio and road lighting condition and the relationship between power consumption and road lighting condition have been studied and explained. A media variable “economic cost” has been chosen which is used for making a connection between these two relationships. The evaluations of NRTAs and power consumption from cost point of view are introduced as well. The impacts of each internal factor defined by author are explained carefully. The result of the model based on these relationships and internal influencing factors is presented in the paper. Finally, the recommendations for reducing NRTAs and/or power consumption, as well as other interesting areas for further study are presented.</p>

Nowadays, NRTS (Nighttime Road Traffic Safety) and energy saving are very hot topics in transportation field. This thesis investigates a general optimal model for minimizing NRTAs (nighttime road traffic accidents) and power consumption of the road lighting. To establish this model, the relationship between N/D RTAs (Night to Day Road Traffic Accidents) ratio and road lighting condition and the relationship between power consumption and road lighting condition have been studied and explained. A media variable “economic cost” has been chosen which is used for making a connection between these two relationships. The evaluations of NRTAs and power consumption from cost point of view are introduced as well. The impacts of each internal factor defined by author are explained carefully. The result of the model based on these relationships and internal influencing factors is presented in the paper. Finally, the recommendations for reducing NRTAs and/or power consumption, as well as other interesting areas for further study are presented.

National and international studies and statistics show that road trauma is the leading cause of injury and death of children to age 14 years. One contributing element of this trauma among children relates to pedestrian accidents. Reducing child pedestrian trauma is a complex problem requiring a multi-faceted approach. One approach is through education. This evaluative study explored the links between the implementation of RoadSmart, a new primary school road safety education program developed by VicRoads, and the road crossing behaviour of children in year 2.A process-outcome approach was employed which focused on both the implementation and outcome components of the year 2 "Walking safely" component of the RoadSmart program. RoadSmart offers children first-hand experiences of real-traffic situations and comprises two major parts - school based learning sequences and take-home activities, designed to involve parents/carers in educating their children about road safety. Pre and post unobtrusive observations were undertaken of participating children crossing the road at an unmarked mid-block location and were matched for 44 children. The program was also systematically observed in the classrooms of these students. The findings imply that if teachers implement RoadSmart in the intended manner, students cross roads more safely. Overall findings from this evaluation concur with those of other researchers(Demetre et al., 1993; Rivara, 1990; Roberts, 1980; Thomson et al., 1996), that children under 9 possess capabilities that can be fostered through education and real-street experience to enable them to function more effectively in the traffic environment.

No description available.

Thèse réalisée en cotutelle, sous la direction de M. Philippe Despoix (Université de Montréal) et de M. Michel Marie (Université Sorbonne Nouvelle-Paris 3) / Apparu au lendemain de la Seconde Guerre mondiale avec la publication en 1957 d’On the Road de Jack Kerouac et la sortie, 12 ans plus tard, d’Easy Rider de Dennis Hopper, le road novel et le road movie constituent à nos yeux les deux versants de ce que nous avons choisi de nommer le récit de la route. Devant l’absence de réelle étude conjointe entre les deux formes et la persistance d’amalgames, nous souhaitons mettre en évidence ce qui permettrait de distinguer le road novel et le road movie d’autres récits d’errance. Un tel travail nécessite la mise au jour d’un outil d’analyse intermédial permettant d’embrasser de concert des œuvres relevant d’expressions médiatiques différentes. Nous proposons donc de recourir au concept de chronotope développé par Bakhtine en littérature, et dont il a été démontré il y a peu qu’il est aussi susceptible de s’appliquer à un objet cinématographique. Nous posons que road novel et road movie reposent sur la combinaison d’un ensemble de chronotopes fondamentaux : celui de la route, dans le contexte de la motorisation et des non-lieux de la postmodernité, et celui du seuil, compris comme l’expression du tournant d’une vie. La présence d’une dimension parodique nous amène en outre à mobiliser un autre concept bakhtinien : celui de carnavalesque, qui s’articulerait justement autour des chronotopes de la route et du seuil définis précédemment. Afin de procéder à cette analyse chronotopique, nous nous appuyons sur un corpus d’œuvres empruntées au répertoire américain, québécois et allemand, en raison notamment des multiples passerelles susceptibles d’être érigées entre ces différentes cultures. / Appearing in the wake of World War II, with the publication in 1957 of On the Road by Jack Kerouac, followed 12 years later with the screening of Denis Hopper’s Easy Rider, the road novel and road movie constitute, we argue, two sides of what we call the road narrative. Faced with a lack of comprehensive studies embracing both sides concurrently, and with recurrent amalgams, we reflect on the components differentiating the road novel and road movie from other types of wandering stories. Such a project calls for the construction of an intermedial apparatus, enabling us to jointly encompass artworks belonging to different media formats. Consequently, we build on the concept of the chronotope, as developed by Bakhtin as a tool for literary criticism, and recently extended by scholars to cinematographic objects. We show how road novels and road movies emerge from the combination of two fundamental chronotopes: that of the road, exemplified by a postmodern universe dominated by motor vehicles and non-places, and that of the threshold, understood as the expression of a critical turn in one’s life. The noted presence of a parodic dimension in road narratives calls for the introduction of an additional bakhtinian concept: the carnivalesque, which, as we show, can be articulated in relation to the previously defined road and threshold chronotopes. For this chronotopical analysis, we selected artworks from the American, Quebecois and German repertoires, a choice justified by the numerous potential connections to be established between those three different cultures.

Apparu au lendemain de la Seconde Guerre mondiale avec la publication en 1957 d’On the Road de Jack Kerouac et la sortie, 12 ans plus tard, d’Easy Rider de Dennis Hopper, le road novel et le road movie constituent à nos yeux les deux versants de ce que nous avons choisi de nommer le récit de la route. Devant l’absence de réelle étude conjointe entre les deux formes et la persistance d’amalgames, nous souhaitons mettre en évidence ce qui permettrait de distinguer le road novel et le road movie d’autres récits d’errance. Un tel travail nécessite la mise au jour d’un outil d’analyse intermédial permettant d’embrasser de concert des œuvres relevant d’expressions médiatiques différentes. Nous proposons donc de recourir au concept de chronotope développé par Bakhtine en littérature, et dont il a été démontré il y a peu qu’il est aussi susceptible de s’appliquer à un objet cinématographique. Nous posons que road novel et road movie reposent sur la combinaison d’un ensemble de chronotopes fondamentaux : celui de la route, dans le contexte de la motorisation et des non-lieux de la postmodernité, et celui du seuil, compris comme l’expression du tournant d’une vie. La présence d’une dimension parodique nous amène en outre à mobiliser un autre concept bakhtinien : celui de carnavalesque, qui s’articulerait justement autour des chronotopes de la route et du seuil définis précédemment. Afin de procéder à cette analyse chronotopique, nous nous appuyons sur un corpus d’œuvres empruntées au répertoire américain, québécois et allemand, en raison notamment des multiples passerelles susceptibles d’être érigées entre ces différentes cultures. / Appearing in the wake of World War II, with the publication in 1957 of On the Road by Jack Kerouac, followed 12 years later with the screening of Denis Hopper’s Easy Rider, the road novel and road movie constitute, we argue, two sides of what we call the road narrative. Faced with a lack of comprehensive studies embracing both sides concurrently, and with recurrent amalgams, we reflect on the components differentiating the road novel and road movie from other types of wandering stories. Such a project calls for the construction of an intermedial apparatus, enabling us to jointly encompass artworks belonging to different media formats. Consequently, we build on the concept of the chronotope, as developed by Bakhtin as a tool for literary criticism, and recently extended by scholars to cinematographic objects. We show how road novels and road movies emerge from the combination of two fundamental chronotopes: that of the road, exemplified by a postmodern universe dominated by motor vehicles and non-places, and that of the threshold, understood as the expression of a critical turn in one’s life. The noted presence of a parodic dimension in road narratives calls for the introduction of an additional bakhtinian concept: the carnivalesque, which, as we show, can be articulated in relation to the previously defined road and threshold chronotopes. For this chronotopical analysis, we selected artworks from the American, Quebecois and German repertoires, a choice justified by the numerous potential connections to be established between those three different cultures. / Thèse réalisée en cotutelle, sous la direction de M. Philippe Despoix (Université de Montréal) et de M. Michel Marie (Université Sorbonne Nouvelle-Paris 3)

The cost of a road construction over its service life is a function of design, quality of construction as well as maintenance strategies and operations. An optimal life-cycle cost for a road requires evaluations of the above mentioned components. Unfortunately, road designers often neglect a very important aspect, namely, the possibility to perform future maintenance activities. Focus is mainly directed towards other aspects such as investment costs, traffic safety, aesthetic appearance, regional development and environmental effects. This doctoral thesis presents the results of a research project aimed to increase consideration of road maintenance aspects in the planning and design process. The following subgoals were established: Identify the obstacles that prevent adequate consideration of future maintenance during the road planning and design process; and Examine optimisation of life-cycle costs as an approach towards increased efficiency during the road planning and design process. The research project started with a literature review aimed at evaluating the extent to which maintenance aspects are considered during road planning and design as an improvement potential for maintenance efficiency. Efforts made by road authorities to increase efficiency, especially maintenance efficiency, were evaluated. The results indicated that all the evaluated efforts had one thing in common, namely ignorance of the interrelationship between geometrical road design and maintenance as an effective tool to increase maintenance efficiency. Focus has mainly been on improving operating practises and maintenance procedures. This fact might also explain why some efforts to increase maintenance efficiency have been less successful. An investigation was conducted to identify the problems and difficulties, which obstruct due consideration of maintainability during the road planning and design process. A method called “Change Analysis” was used to analyse data collected during interviews with experts in road design and maintenance. The study indicated a complex combination of problems which result in inadequate consideration of maintenance aspects when planning and designing roads. The identified problems were classified into six categories: insufficient consulting, insufficient knowledge, regulations and specifications without consideration of maintenance aspects, insufficient planning and design activities, inadequate organisation and demands from other authorities. Several urgent needs for changes to eliminate these problems were identified. One of the problems identified in the above mentioned study as an obstacle for due consideration of maintenance aspects during road design was the absence of a model for calculating life-cycle costs for roads. Because of this lack of knowledge, the research project focused on implementing a new approach for calculating and analysing life-cycle costs for roads with emphasis on the relationship between road design and road maintainability. Road barriers were chosen as an example. The ambition is to develop this approach to cover other road components at a later stage. A study was conducted to quantify repair rates for barriers and associated repair costs as one of the major maintenance costs for road barriers. A method called “Case Study Research Method” was used to analyse the effect of several factors on barrier repairs costs, such as barrier type, road type, posted speed and seasonal effect. The analyses were based on documented data associated with 1625 repairs conducted in four different geographical regions in Sweden during 2006. A model for calculation of average repair costs per vehicle kilometres was created. Significant differences in the barrier repair costs were found between the studied barrier types. In another study, the injuries associated with road barrier collisions and the corresponding influencing factors were analysed. The analyses in this study were based on documented data from actual barrier collisions between 2005 and 2008 in Sweden. The result was used to calculate the cost for injuries associated with barrier collisions as a part of the socio-economic cost for road barriers. The results showed significant differences in the number of injuries associated with collisions with different barrier types. To calculate and analyse life-cycle costs for road barriers a new approach was developed based on a method called “Activity-based Life-cycle Costing”. By modelling uncertainties, the presented approach gives a possibility to identify and analyse factors crucial for optimising life-cycle costs. The study showed a great potential to increase road maintenance efficiency through road design. It also showed that road components with low investment costs might not be the best choice when including maintenance and socio-economic aspects. The difficulties and problems faced during the collection of data for calculating life-cycle costs for road barriers indicated a great need for improving current data collecting and archiving procedures. The research focused on Swedish road planning and design. However, the conclusions can be applied to other Nordic countries, where weather conditions and road design practices are similar. The general methodological approaches used in this research project may be applied also to other studies. / <p>QC 20110407</p>

Thesis(PhD (Civil Engineering))-- University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Bitumen based road surfacing seals and asphalt wearing courses have been used by society's Engineers "to counter the damage to the existing unsurfaced roadways by the newly developed automobile with its rubber driving wheels" since the early 1900's. Early experiments were conducted with both tar and bitumen to find a suitable material to alleviate the situation, and ongoing research has been carried out through the past century and into the new millennium, throughout the world, examining improvements, from materials used, to design and construction methods. However, there is still much to be understood, improved and refined, when considering road surfacing seal design. Pavement designers have the choice of utilizing either an asphalt (graded aggregate remanufactured with a bitumen binder and applied as a complete product) or a surfacing seal (including variations of bitumen binder sprayed onto the road surface, with the addition of single size stones, either in one or two layers of binder and aggregate, i.e. single or double seals) as a pavement wearing course. Current road surfacing seal design practice depends on empirical analysis and experience, being primarily a volumetric based assessment of bitumen application. This research project assesses South African seal design philosophy, investigates design areas where review or updating is required to accommodate changing bitumen sources and types, and traffic loading. Seal performance criteria are examined, with the development of a matrix of influences on seal performance. Using this, the need for a seal design method based on mechanistic material properties is proposed, and the prototype example of such a numerical model using finite element method is presented. To contribute further towards a performance related seal design method, the feasibility of modelling of road surfacing seals using mechanistic principles was examined. The potential of developing failure and fatigue criteria or relationships to enable assessment of the expected seal performance, with inclusion of different component material characteristics and variations, varying traffic and environmental conditions, was also examined. From assessment of literature, and understanding of the components of the seal, pavement, and influencing factors, a choice of numerical model of seal performance was made. The Finite Element Method (FEM) Analysis was selected for the purpose of modelling seal performance. The model was developed to enable examination of the interaction of individual seal components (i.e. stone and bitumen), at micro-mechanic scale. The prototype 3-dimensional numerical seal model was undertaken in 2002 and 2003 at Technical University Delft, using the CAPA research program. On the basis of the linear calculations the developed numerical prototype model is able to provide insight into seal behaviour and distinction between mechanical (seal geometry) and chemical (components) seal aspects, and insight into stress and strain development in the different seal types. Simulations of different seal, environmental and traffic scenarios are provided to demonstrate the potential of the model (excluding seal aggregate interlock and embedment effects at prototype stage). In order to provide data for the verification of the prototype numerical model, and to further contribute to the development of a performance related seal design method, performance tests were developed, with a new tool for assessment of comparative seal performance using the Model Mobile Load Simulator Accelerated Pavement Testing apparatus. The performance of each different seal binder type - Penetration grade Mumen, SBS, SBR, EVA and Bitumen Rubber - was undertaken. A methodology for the assessment of in-service seal performance was developed, and the performance of the respective seals reported. The results of this examination showed that each binder type has its unique contribution to seal performance. These new performance tests will be able to assist designers in the added determination of the fundamental binder properties on seal performance, and the seals' ability to contribute to the overall performance of the pavement. An additional comparative performance test method was developed to enable assessment of the effect of ageing and moisture, to complement the MMLS results. In summary, the performance testing has assisted in identifying the critical parameters a seal designer should consider during the design process. From this research, it is evident that the current seal design method requires further development to able designers to predict the effect of: Varying axle loads, tyre pressures and design speed; Varying characteristics of the different binders, (i.e. temperature - viscosity relationships, adhesion and visco-elastic behaviour); on the performance of seals. The major areas for suggested improvement in current seal design methods towards a performance based design method are: inclusion of variable traffic load and environmental characteristics, including temperature and moisture influences, and inclusion of mechanistic material characteristics into the design methodology. / AFRIKAANSE OPSOMMING: Bitumengebaseerde padoppervlakseellae en asfaltslytlae is sedert die 1900's deur ingenieurs gebruik as teenwig teen die skade wat die pas ontwikkelde voertuig met sy rubberwiele aan bestaande ryvlakke sonder oppervlakbehandeling aangerig het. In vroeëre eksperimente wat daarop gemik was om 'n geskikte materiaal te vind om die probleem teen te werk, is 'n kombinasie van teer en bitumen gebruik. Sedertdien word voortgesette navorsing steeds wêreldwyd gedoen om verbeterings te ondersoek, nie net ten opsigte van materiale nie maar ook ontwerp- en konstruksiemetodes. Wat die ontwerp van padoppervlakseëling betref is daar egter heelwat wat reg begryp, verbeter en verfyn moet word. Plaveiselontwerpers het die keuse om of 'n asfalt te gebruik (gegradeerde aggregaat voorafvervaardig met 'n bitumen bindmiddel en aangewend as 'n klaarproduk), of 'n oppervlakseël (een laag of twee lae [m.a.w. enkel- of dubbelseël] bitumen bindmiddel met aggregaat [enkelgrootte klippies] bygevoeg, gespuit op die padoppervlak). In die praktyk berus die ontwerp van padoppervlakseëling tans op empiriese analise en ervaring (wat hoofsaaklik 'n volumetriesgebaseerde assessering van die aanwending van bitumen is). Hierdie navorsingsprojek doen 'n waardebepaling van die Suid-Afrikaanse filosofie van seëlontwerp, en ondersoek ontwerpterreine wat hersiening of bywerking benodig om vir veranderende bitumenbronne en -tipes, asook verkeerslading, voorsiening te maak. Met die ontwikkeling van 'n matriks van die invloede op seëlprestasie is die kriteria vir seëlprestasie ondersoek. Op grond daarvan word aangevoer dat daar 'n behoefte is aan 'n seëlontwerpmetode gebaseer op die meganistiese eienskappe van materiaal, en word 'n voorbeeld van 'n numeriese modelprototipe wat die eindige-element-metode gebruik, voorgelê. Ten einde 'n verdere bydrae te lewer tot die ontwikkeling van 'n prestasiegerigte seëlontwerpmetode, is die uitvoerbaarheid van die modellering van padoppervlakseëllae gebaseer op meganistiese beginsels, ondersoek. Daar is ook ondersoek ingestel na die potensiaal vir die ontwikkeling van kriteria vir die vasstel van mislukking en vermoeidheid of verhoudinge wat die assessering van die verwagte seëlprestasie (ingesluit die verskillende kenmerke en variasies van seëlkomponentmateriaal en wisselende verkeers- en omgewingsomstandighede) moontlik kan maak. Met oorweging van die bestudeerde literatuur en 'n begrip van die komponente van seël, plaveisel en inwerkende faktore, is 'n keuse van 'n numeriese model vir seëlprestasie gemaak. Die eindige-element-metode (Finite Element Method [FEM]) is gekies as die analitiese metode vir die modellering van seëlprestasie. Die model is ontwikkel om die ondersoek van die interaksie tussen individuele seëlkomponente (klip en bitumen) op mikromeganiese skaal moontlik te maak. Die ontwikkeling van die driedimensionele, numeriese, model-seëlprototipe is tussen 2002 en 2003 by die Delft Tegniese Universiteit gedoen, met gebruikmaking van die CAPA-navorsingsprogram. Wat lineêre berekenings betref, kan die ontwikkelde numeriese modelprototipe 'n insig gee in seëlgedrag en in die onderskeid tussen aspekte van seëlgeometrie (meganies) en seëlkomponente (chemies), asook in die spanning- en vervormingsontwikkeling van die verskillende tipes seël. Simulasies van verskillende seël-, omgewings- en verkeerscenario's word voorgestel om die potensiaal van die modelprototipe te demonstreer. Met die oog daarop om data vir die verifikasie van die numeriese modelprototipe te voorsien, en om verder tot die ontwikkeling van 'n prestasiegerigte seëlontwerpmetode by te dra, is prestasietoetse, met 'n nuwe instrument vir die assessering van vergelykende seëlprestasie met behulp van die Model Mobile Load Simulator Accelerated Pavement Testing apparaat, ontwikkel. Die prestasie van elke verskillende tipe seëlbindmiddel- penetrasiegraad bitumen, SBS, SBR, EVA en bitumenrubber - is getoets. 'n Metodologie vir die assessering van die ingebruiksprestasie van seëllae is ontwikkel, en daar is verslag gedoen oor die prestasie van die verskillende seëllae. Die resultate van die ondersoek het getoon dat elke tipe bindmiddel 'n eie unieke bydrae tot die prestasie van die seël lewer. Die nuwe prestasietoets sal ontwerpers help met die bepaling van die grondliggende bindmiddeleienskappe wat by seëlprestasie ter sprake is, asook van die seël se vermoë om tot die algehele prestasie van die plaveisel by te dra. 'n Bykomende prestasievergelykingstoetsmetode vir die assessering van die effek van veroudering en vogtigheid is ontwikkel om die MMLS-resultate aan te vul. Ter opsomming, die prestasietoetsing het bygedra tot die identifisering van die kritiese parameters wat die seëlontwerper tydens die ontwerpproses in gedagte behoort te hou. Die navorsing wat gedoen is, dui daarop dat die huidige seëlontwerpmetode verder ontwikkel moet word om ontwerpers in staat te stel om die effek van die volgende te kan voorspel: Wisselende aslas, banddruk en ontwerpspoed; Verskillende kenmerke van die verskillende bindmiddels (bv. temperatuur viskositeitsverhoudinge, vashegting en viskoëlastiese gedrag). Wat huidige seëlontwerpmetodes betref, is die hoofterreine waarop 'n verbetering voorgestel word, die insluiting van veranderlike verkeerslas- en omgewingskenmerke, ingesluit die invloed van temperatuur en vogtigheid, en insluiting van meganistiese kenmerke van materiaal in die ontwerpmetodologie.

The erection of tollgates along the N1 freeway has triggered a great deal of interest. As a result of the toll fees, traffic has been diverted to alternative roads. This study investigates how traffic diverted from the toll road affect the welfare of users of the alternative road. The literature review provides a theoretical framework of economic impact assessment and road pricing. Furthermore, the literature study reviews previous studies of a similar nature and compare them with the findings of this study. There is no conclusive evidence that diversion of traffic from the N1 causes congestion on the R101 and has a negative impact on the economy of the region. On the contrary, evidence suggests that there was an initial diversion of traffic when the toll came into operation but that is slowly filtered back after six months. In the application of the RED model, economic benefits are derived from user benefits, which is a function of savings in VOC’s and time of normal and generated traffic on a road or saving due to an improvement in road safety, resulting from improved roads. A decrease in traffic has a measurable effect on vehicle travel speeds and travel time only when the roads are significantly congested. In the case of scenario 1 (including diversion), frequent maintenance needs to be performed under increased traffic. Increased traffic due to “diverted traffic” causes congestion in accidents and travelling time, which is a cost to the economy. Under scenario 2 (excluding diversion), it is assumed that ADT will return to normal. Due to lower levels of congestion and travelling times would be faster, while maintenance costs and accident rates would decrease. Scenario 2 is selected as being economically the most feasible option. It is clear that the R101 cannot cope with the current levels of traffic and congestion. One can speculate about the causes of the congestion but in order to derive at a solution to the problem more research needs to be done on the cause of the congestion in order to resolve the problem. / Dissertation (Magister Commercii)--University of Pretoria, 2007. / Economics / unrestricted