Добірка наукової літератури з теми "Surface wearing course"

The bonding strength provided by the tack coat between asphalt concrete layers at the interface is considered as an essential issue in the performance of the flexible pavement throughout its service life. However, the surface texture of the pavement surface exhibits another essential issue in the bond strength. In this investigation, three layers of asphalt concrete (base, binder and wearing) courses with (25, 19, and 12.5) mm of nominal maximum size of aggregates have been prepared using roller compactor. Rapid curing cutback RC-70 and cationic medium setting emulsion CMS have been implemented as tack coats with three application rates. The slab specimens were subjected to mean texture depth determination using sand patch method. Core specimens of 102 mm diameter were obtained from the prepared slab samples and subjected to interface bond strength test with the aid of a special manufactured mold. Test results were analyzed and compared. It was concluded that when RC-70 tack coat was implemented, asphalt concrete binder course laid on base course exhibited the highest shear strength of 1600 kPa at an application rate of 0.33 liter/m2 when compared to other application rates. Asphalt concrete wearing course laid on binder course exhibited the highest shear strength of 1515 kPa at an application rate of 0.15 liter/m2 when compared to other application rates. When CMS tack coat was implemented, asphalt concrete binder course laid on base course exhibited the highest shear strength of 1620 kPa at an application rate of 0.23 liter/m2 when compared to other application rates. Finally, the asphalt concrete wearing course laid on binder course exhibited the highest shear strength of 2272 kPa at an application rate of 0.23 liter/m2 when compared to other application rates.

There are many innovative highway surfaces. One it is the surface from porous asphalt. The purpose of construction this pavements is to absorb rainwater and to reduce the noise of the wearing course. The evaluation of the effectiveness of these features can be carried out by various methods including statistical method, CPX, or equivalent noise measurement. During exploitation, the following is assessed: the impact of factors as air humidity, wind, or intensity and the structure of road traffi c during the period of exploitation. This study presents an analysis of measurement results and methods for assessing the impact of these factors, which can be used to plan the reconstruction of porous wearing course.

Abstract The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

AbstractThe aggregate applied for the wearing course has a significant influence on skid resistance of road surfaces. However, it is difficult to evaluate the behaviour of road surface in use on the basis of the Polished Stone Value (PSV) determined for the aggregate according to the so called ‘British method’. The British method, which is currently used in many countries, does not allow to determine the influence of neither the grain size of the aggregate nor the type of the wearing course on skid resistance of road surface. The present paper suggests a method for evaluation of the British Pendulum Number (BPN) for road surfaces in laboratory conditions. The authors assumed the BPN for polished slabs, made from asphalt mixtures, as the criterion. The index was measured with the British Pendulum Tester. The simulation of the process was conducted on research stand (called slab polisher) built at Bialystok University of Technology (BUT). The results of laboratory tests indicate that surfaces from asphalt concrete (AC) have slightly higher values of BPN in comparison with the values determined for surfaces made from stone mastic asphalt (SMA).

Currently, a large part of the forest roads that were built using the bituminous surface technology in the second half of the last century have been worn out. This means that forest owners and forest managers urgently need to determine the amount and extent of this damage and establish a suitable repair plan, which demands both time and staff. The aim of the study is to verify whether it is possible, and with what precision, to detect the damage of the wearing course by means of unmanned aerial systems, which would facilitate and accelerate this process and possibly make it cheaper. A 3D model of a forest road was created using photos of the current state of a damaged part of a forest road. The aerial photographs were taken by an unmanned aircraft. To verify the accuracy of the model, cross sections of the road surface were surveyed tachymetrically and compared with the cross sections created in the 3D model in ArcMap, from photogrammetric pointcloud using aerial photographs from the unmanned aircraft. The RMSE of the values of the control points in the 3D model cross sections compared to the values of the points in the tachymetric measurement of the cross sections reached to within 0.0198 m. The results of the tested road section showed that the unmanned aerial systems can be used to detect the forest road surface damage with the difference in accuracy being up to 2 cm compared with the accuracy of the current tachymetric methods. Based on the results we can conclude that the used method is appropriate for detailed monitoring of the condition of the asphalt wearing course of forest roads and allows for a precise and objective localization and quantification of damage.

An evaluation of the acoustic and surface characteristics of different Canadian pavement types was carried out in 2013 at the test track of the Centre for Pavement and Transportation Technology at the University of Waterloo. Noise testing was performed to determine the coefficient of noise absorption on cored samples and noise emissions in the field using the close proximity and the on-board sound intensity methods. Wearing course characteristics were evaluated with field testing, including visual condition surveys, evaluation of frictional properties with the British Pendulum tester, mean texture depth measurements, and surface profile and roughness evaluation with a walking profiler. As of the time of testing, the noise testing results indicate comparable acoustic properties in both flexible and rigid pavement sections, despite differences in the initial pavement materials, mixes, and surface finishing. With increasing pavement age, the amount of noise emissions increases as the pavement surface is worn down. Comparable friction values are also observed in all pavement sections, in line with the noise testing results. However, this is largely based on the initial construction values. Surface distresses are also not uniformly distributed: they are more severe in the oldest sections and more frequent in the loaded lane, which carries the heaviest traffic loads.

Stiffness is an important mechanical characteristic of asphalt mixtures used in the wearing course. It is one of the determining factors in the generation of tyre/road noise. The dynamic stiffness of the upper layer of the road surface depends on the physical and mechanical properties of the materials it is composed of, and traffic load. Determination of dynamic stiffness, both in laboratory conditions and in situ, requires consideration of many other factors. Tests of dynamic properties of road surfaces in field conditions are most often conducted with the help of modal hammers. Impulse excitation results are usually less accurate than those in the application of modal exciters. The test stand was constructed, comprising a tripod, 32-channel and 24-bit data acquisition system, exciter, signal amplifier, impedance head, single-axis piezoelectric accelerometers and a stinger. The test stand and the proposed method of measuring dynamic stiffness do not require the determination of the resonance frequency of the tested specimen and can be used both on various types of bituminous mixtures of varying shape and dimensions, as well as directly on the upper surface of the wearing course of bituminous pavements. The test results showed that the type of bituminous mixture used in the wearing course significantly affects its dynamic stiffness. The dynamic stiffness level of asphalt concrete, stone mastic asphalt and porous asphalt layers was determined to be similar. The addition of rubber granulates significantly reduced its rigidity, which is very beneficial from the point of view of reducing the tyre/road noise.

<p>Susunan lapisan perkerasan jalan mempunyai fungsi untuk menopang dan mendistribusikan beban lalu lintas dengan tujuan tidak menimbulkan kegagalan konstruksi atau kerusakan yang berarti terhadap konstruksi jalan yang sudah terbentuk. Berkaitan dengan kinerja lapis permukaan perkerasan jalan (<em>surface course</em>) yang berpegang pada prinsip <em>long life performance</em>, maka guna mewujudkan hal tersebut dibuatlah suatu rancangan campuran rencana (<em>Design Mix Formula, </em>DMF) sesuai dengan fungsi jalan. Tujuan penelitian adalah menganalisa nilai stabilitas dan fleksibilitas terhadap nilai porositas campuran aspal panas akibat <em>poor graded</em> campuran AC-WC spesifikasi teknik PU Bina Marga Tahun 2010 yang menyimpang dari rancangan campuran rencana optimum berdasarkan pengujian di laboratorium dengan menggunakan metode Marshall. Berdasarkan target awal gradasi campuran agregat beton aspal Laston AC-WC sesuai spesikasi teknis Bina Marga Tahun 2010 diperoleh nilai Kadar Aspal Optimum (KAO) sebesar 6,1%. Penyimpangan target gradasi campuran agregat mengakibatkan perubahan sifat campuran panas beton aspal Laston AC-WC. Penyimpangan sifat campuran beton aspal Laston AC-WC kondisi KAO = 6,1% terbesar terjadi pada target gradasi senjang campuran agregat tipe 2 terhadap target gradasi awal campuran agregat Laston AC-WC.</p>

Haul road pavement condition has long been considered as having a significant influence on the efficiency of haulage in surface mining. However limited literature exists relating wearing course condition with performance, resulting in mine operators not maximising the potential value of their haul road assets. This project focuses on defining current issues associated with the functional performance of haul roads, through a case study involving three iron ore mines in the Pilbara region of Western Australia. Consequently attempts are then made to relate material properties to performance so that existing criteria can be verified or refined. Cementitious stabilisation and naturally occurring gravels found adjacent to the mines involved in the case study are then trialled via laboratory testing, show promise and lead to a recommendation of subsequent field trials. Pavement lifetime costing is finally completed with the Pilbara environment as the basis, utilising the most appropriate models currently available for pavement condition and vehicle operating and maintenance costs. This resulted in a lack of variability due to material properties, with maintenance variables having a greater effect. Lastly it is found that potential production loss values (net reduction in ore hauled) outweigh expenditure on improved maintenance practice or even material treatments.

The diploma thesis deals with the problems of pavement surface skid resistence of wearing course of asphalt mixtures with R-material. Specifically, it is a mixture of type ACO 11 (asphalt concrete for wearing layers). In the theoretical part of the thesis there are dismantled the problems of Antiskid properties of the road surface and recycling of R-material. The practical part is dedicated to the design and laboratory production of the asphalt mixture ACO 11 without admixture of R-material and with content of 38 % R-material. In addition, the results of the measurement of friction coefficient after smoothed for these bitumen mixtures are shown in the work. The aim of the thesis was to determine the influence of the increased content of R-material on the anti-skid properties of the road surface as it is planned to update the standard ČSN EN 13108-1, which will allow the use of up to 40 % R-material into the mixtures of type ACO 11.

La production de l’huile de palme génère plusieurs déchets dont les coques de noix de palmistes (CNP). Face à l’épuisement des ressources naturelles, utilisables en technique routière, la valorisation des déchets agricoles comme les coques de noix de palmiste constitue une solution alternative d’avenir pour les pays producteurs du palmier à huile. Cette thèse étudie l’utilisation des coques de noix de palmiste comme agrégat grossier dans la formulation des composites, proposables comme matériaux de couches d’assises des chaussées à faible trafic. La première partie du manuscrit traite de l’élaboration des mélanges des coques de noix de palmiste et de la terre de barre (terre latéritique abondante dans le sud du Bénin) pour une utilisation en couche de fondation. Les proportions volumiques de chaque composite sont déterminées par la loi parabolique de Fuller-Thompson. Au laboratoire, les essais géotechniques sur le sol latéritique et sur les composites ont montré que l’ajout de 61% des CNP à la terre de barre augmente l’indice CBR de 76% à 95% de l’optimum Proctor Modifié. L’ajout de 15% de sable lagunaire dans la formulation a permis de réduire la plasticité de 29%. Ainsi, le composite (39 % de sol latéritique + 61 % de CNP) avec un indice CBR égal à 30 et le composite (45 % de sol latéritique, 40 % de CNP et 15 % de sable de lagune) avec un indice CBR égal à 41 sont utilisables en couche de fondation des routes à faible trafic. La deuxième partie est consacrée au remplacement dans un béton bitumineux semi grenu 0/10 utilisable en couche de roulement des gros granulats classiques par les coques de noix de palmiste. Les différentes compositions granulaires sont obtenues par le modèle d’empilement compressible de De Larrard. La tenue à l’eau, étudiée à travers l’essai de Duriez montre que les CNP peuvent remplacer les granulats grossiers dans les enrobés des chaussées à faible trafic. La valorisation des coques de noix de palmistes en technique routière, constitue une grosse solution technico- économique dans le désenclavement des milieux ruraux des pays tropicaux et surtout pour le transport des produits des zones de production vers celles de transformation et de consommation
The production of palm oil generates several wastes including palm kernel shells (PKS). Facing the depletion of natural resources that can be used in pavement construction, the recovery of agricultural waste such as palm kernel shells is an alternative solution for the future for oil palm producing countries. This thesis studies the use of palm kernel shells as coarse aggregate in the formulation of composites materials. The latter can be used as subbase course materials for low-traffic pavements. The first part of the manuscript deals with the production of mixtures of palm kernel shells and lateritic soil (lateritic soil abundant in the south of Benin) for use as a foundation layer. Parabolic law of Fuller-Thompson is utilized to determine the volume proportions of each composite. In the laboratory, geotechnical experiments on lateritic soil and on composites have shown that the addition of 61% PKS increases the CBR index from 76% to 95% of the Modified Proctor optimum. The addition of 15% lagoon sand in the formulation decreases the plasticity by 29%. Thus, the composites with a CBR index of 30 (39% lateritic soil + 61% PKS) and 41 (45% lateritic soil, 40% PKS and 15% lagoon sand) can be used in the foundation layer for low traffic roads. The second part focuses on the substitution of the traditional coarse aggregates by palm kernel shells in a semi-grained bituminous concrete 0/10. This type of asphalt is usable in surface wearing course. The different granular compositions are obtained by the compressible stacking model of De Larrard. The moisture resistance, studied through the Duriez test, shows that PKS can be a good alternative of coarse aggregates in lightly trafficked pavement mixes. The valorization of palm kernel shells in transportation technology is a major technical and economical solution to provide a better access to the rural areas in tropical countries. Especially, it can be useful for the transport of products from production areas to those of processing and consumption

Road safety is a complex problem. It is influenced mainly by the driver, the vehicle and the road surface. This thesis is focused on the road surface properties and especially skid resistance that directly affect the braking distance and keeping the vehicle in the horizontal curves and thus traffic accidents. The thesis deals with the durability of pavement surface skid resistance, the type of pavement layers and aggregate polishing used in wearing course. The aim of this thesis was to develop the methodology for improvement of road surfaces skid resistance durability and implementation of functional test for their assessment.

Unpaved mine haul roads provide the principal means of material transport on surface strip coal mines. With the expansion of surface mining in South Africa and in particular coal strip mining, the use of ultra-heavy off-highway trucks, currently capable of hauling payloads in excess of 160t, has become commonplace. Design and management of these roads was based primarily on local experience and adopted empirical guidelines. This design method served its purpose in an era when off-highway trucks were lighter and less financial outlay was required, both in terms of initial pavement construction costs, ongoing road maintenance costs and vehicle maintenance costs. As the trend in increasing truck size continues, these current pavement design and management systems proved inadequate. Not only would the maintenance costs of existing roads increase, vehicle operating and maintenance costs would also increase prohibitively. The primary objective of this research was the development of a portable and practical total haul road design and management methodology that encompasses both pavement strength, wearing course functionality and road maintenance management components. The structural design concerns the ability of a haul road to carry the imposed loads without the need for excessive maintenance. A revised mechanistically derived structural design is presented together with the associated limiting design criteria and recommended target effective elastic modulus values for the construction materials available. The placement of those materials as pavement layers, such as to optimise their performance both as individual layers and over the entire structure is analysed. Functional design aspects refer to the ability of the haul road to perform its function, i.e to provide an economic, safe and vehicle friendly ride. This is dictated to a large degree through the choice, application and maintenance of wearing course materials. The development and analysis of suitable material selection guidelines for use in haul road functional design was allied to the development of a qualitative defect assessment and ranking methodology in order to assess the utility of established performance related selection guidelines and as a basis for revised functional performance parameter specification. A revised range of parameters was derived based on road-user acceptability criteria. By "analysing the trends evident in the individual defect rankings, the predictive capability of the specification was enhanced by depicting the typical functional defects arising when departures are made from the recommended material property limits. Maintenance design concerns the optimal frequency of wearing course maintenance commensurate with minimum vehicle operating and road maintenance costs. A qualitative road roughness evaluation technique was developed as a precursor to the development of a model for roughness progression. Expressions were developed to enable direct comparison to be made between the qualitative roughness defect score and International Roughness Index (IRI). The second element of a maintenance management system was based on models of the variation of vehicle operating and road maintenance costs with a road roughness model. The combination of these models enabled the optimal maintenance strategy to be sought based on the minimisation of these costs. Sub-optimal maintenance strategies were seen to be associated with unwarranted expenditure on total road-user costs. This thesis makes a contribution to the state of knowledge through the development and synthesis of structural, functional and maintenance management aspects of haul road design. The adoption of these revised and improved haul road design methodologies are associated with potentially significant cost savings and operational improvements. AFRIKAANS: Ongeplaveide mynvervoerpaaie voorsien die primêre vervoer metode van materiaal in steenkoolstrookdagmyne. Met die uitbreiding van dagmynbou in Suid-Afrika en in besonder in die steenkoolstrookmynbou, het die gebruik van swaar vervoertrokke alledaags geword. Ontwerp en bestuur van hierdie paaie was hoofsaaldik gebaseer op plaaslike ondervinding en empiriese riglyne. Hierdie ontwerp metode het sy doel gedien in 'n tydperk waarin die trokke ligter en 'n kleiner finansiele uitleg nodig was, beide in tenne van inisiele plaveisel konstruksie kostes en voortdurende padonderhoudskostes en voertuig instanthoudingkostes. Soos wat die tendens van toename in trokgrootte voortduur, sal die huidige plaveisel ontwerp en bestuursstelsels onvoldoende wees. Nie aIleen sal die ondershoudskostes van bestaande paaie verhoog nie, maar voertuigbedryf en -instandhoudingkostes sal buitensporig word. Die primêre doel van die navorsing was die ontwikkeling van 'n oordraagbare en praktiese totale vervoerpadontwerp en bestuursmetodiek wat die plaveiselsterkte, slytlaag funksionele werkverrigting en padonderhoudbestuur komponente insluit. Die strukturele ontwerp behels die vermoe van 'n vervoerpad om die toegepaste las te kan dra sonder die noodsaaklikheid van buitensporige onderhoud. 'n Hersiene meganisties strukturele ontwerp word aangebied tesame met die geassosieerde ontwerpkriterium en aanbevole effektiewe elastisiteitsmoduluswaardes vir die beskikbare konstruksie materiaa1. Die plasing van daardie materiale as plaveisellae, om sodanig hulle werkverrigting te optimeer is, as beide individuele lae en oor die hele struktuur, geanaliseer. verrig, naamlik om 'n ekonomiese, veilige en voertuigvriendelike rit te voorsien. Die ontwikkeling en analise van geskikte materiaal seleksie is gekoppel aan die ontwikkeling van 'n kwalitatiewe defek waardebepaling en ranglys metodiek om die bruikbaarheid van vasgestelde prestasie-verwante seleksie riglyne te kan bepaal en as basis vir hersiene funksionele prestasie parameter spesiftkasies. 'n Hersiene reeks parameters is afgelei, gebaseer op padverbruiker aanvaarbaarheids kriterium. Deur analise van die tendens in die individuele defek ranglys, is die voorspelbaarheids vennoe van die spesifIkasies verhoog deur die uitwysing van tipiese funksionele defekte wat voorkom wanneer afgewyk word van aanbevole materiaal parameter beperkings. Die onderhoud aspek van vervoerpad ontwerp kan nie afsonderlik van die strukturele en funksionele ontwerp aspekte oorweeg word nie. Onderhoudontwerp behels die optimale frekwensie van slytlaag onderhoud eweredig aan die minimum. voertuigbedryf en padonderhoudskostes. 'n Kwalitatiewe pad ongelykheid evaluasie tegniek is ontwikkel as 'n voorloper tot die ontwikkeling van 'n ongelykheid progressie model. Uitdrukkings is ontwikkel om direkte vergelyking tussen ongelykheid defektelling en Internasionale ongelykbeids indeks (IRI) moontlik te maak. Die tweede element van 'n onderhouds bestuurstelsel is gebaseer op modele van die variasie van die voertuigbedryf en instandhoudingkoste en padongelykbeid. Die kombinasie van hierdie modelle stel die verbruiker in staat om die optimale onderhoudstrategie te soek. 'n Sub-optimale padonderhouds strategie was geassosieer met buitensporige besteding op totale padverbruikers koste. Hierdie proefskrif lewer 'n bydrae tot die staat van kennis deur die ontwikkeling en samevoeging van die strukturele, funksionele en onderhoud bestuurs aspekte van mynvervoerpadontwerp. Die ingebruikneming van die hersiene en verbeterde vervaerpad antwerp en bestuur metodiek het die potensiaal am beduidende koste besparings te verwesenlik.
Thesis (PhD)--University of Pretoria, 2011.
Civil Engineering
unrestricted

The pebble is on the beach, once more, unmarked by its brief contact with human sentience. Almost unmarked. The fingerprints that it lightly bears will, however, be washed away by the next tide. It has a long future, still, but probably not as a pebble—though quite how long it remains as a pebble may well depend on human action. Not on immediate, direct human action—whether it is scooped up by a digger and converted into concrete for a sea-front esplanade, for instance, or even collected as a souvenir by some passing tourist. Either of these fates should cause only a brief deflection from its long-term future (the esplanade is, after all, only a cliff to be attacked by the elements, while beach souvenirs are soon discarded). A larger perturbation of its trajectory more probably hinges on wider human effects—but more of that anon. We might assume, first, that nature runs its course. A pebble on a beach, its natural environment, is changing all the time. Not long ago, it was part of a slab of slate in a cliff, then it briefly became an angular chunk of rock, before the waves and water smoothed it down. They are still smoothing it, wearing away at it, making it smaller. Even the contact with human hands probably removed a grain or two. A pebble has the appearance of permanence, but it is not permanent. How long does it take to wear down a pebble? This can happen astonishingly quickly. Even over a single tide, being washed backwards and forwards by every incoming wave, a pebble can become detectably lighter—by less than one tenth of one per cent, admittedly, but that weight difference can easily be measured using modern electronic scales. Over a season, on an exposed part of the coast, a pebble can lose between a third and a half of its mass. The rates will vary—on a stormy day the banging of pebbles against each other can produce distinct percussion marks on their surfaces, while on a calm day the attrition rate will drop markedly. Night and day, though, the pebble is disintegrating.

This paper focuses on problem of loss aggregates on the surface layer of pavements in particular sites such as approaches to roundabouts and pedestrian crossings. Obtaining a long life-wearing course requires more than can be achieved by improving the properties of the wearing course in it. Generally, the traffic loads, temperature variations, the intrusion of water and freeze-thaw cycles, which will reduce the life of the wearing course, regardless of how well it is designed and constructed. The wearing course is an important interdependent component of the whole pavement. A durable and faultless wearing course acts to protect the base layers against the intrusion of water from above, which is essential to maintain its strength and serviceable life. The objective of this study is to evaluate the wear of a controlled set of pavements with various aggregate mixtures. A single parameter is not enough to describe the mechanisms of surface damage but we propose relationships between the constituents used in pavements and loss of aggregates.

Rice husk ash (RHA) is a by-product of rice milling. Its use as soil stabilizer is a way to replace the final disposal with environmental benefit. However, RHA is not cementitious itself but when mixed with lime forms cements which improve the soil properties. A research of performance of a silty sandy soil modified with RHA and lime as wearing course layer of low-volume roads was conducted through two full-scale test sections with different pavements built in Artigas, northern Uruguay. The alkaline reactivity of RHA is low because the husk burning is not controlled. The soil-RHA-lime mix design was conducted according to the Thompson’s Method. The pavement test sections were monitored through deflection measures by Benkelman beam and observations of surface condition. The deflections decreased over time in both test sections due to the development of cementation of the study materials. After one year, the dust emission was reduced, the wet skid resistance of pavement surfaces improved and there was not rutting. The researched pavements have had a good performance under the existing traffic and environmental conditions, demonstrating that wearing course layer of silty sand modified with RHA and lime is an alternative to improve the condition of low-volume roads and to replace the final disposal of RHA, with environmental, social and economic benefits.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3451

Abstract This project focuses on development of method to recycle the onshore drill cuttings waste and use them in road application. The hazardous characteristics of the drill cuttings waste are also tested and evaluated to address concerns in both safety and environment aspects. The project goals are to recycle drill cuttings waste into new use, reduce environmental footprint and waste management cost, as well as promote corporate social responsibility and sustainability development. Potential use of drill cuttings contaminated with synthetic based mud as part of material for road application were investigated. Samples of the drill cuttings were tested for presence of heavy metal. Laboratory tests were performed to evaluate suitable percentage of drill cuttings to be incorporate into aggregate for road pavement. Pilot recycled drill cuttings road was constructed at PTTEP Rapid Scale-Up Center. The environmental impact assessment on soil, surface water, and underground water around pilot road areas are also carried out to investigate potential environmental impact of the pilot road. Results on heavy metal tests indicate that the drill cuttings are non-hazard with concentration of heavy metal within standards specified in the Department of Mineral Fuel Notification on Petroleum Waste Management dated 28 Feb 2013 and is safe for recycling in road application. Laboratory tests performed in collaboration with the Department of Rural Road indicate that 6% of drill cuttings can be incorporated into aggregate for construction of binding course and wearing course of hot-mixed asphalt road. A 1.2-kilometer pilot recycled drill cuttings road with 6% drill cutting incorporated was then constructed at PTTEP Rapid Scale-Up Center (RASC). The pilot road is used as an access road and road surrounding the PTTEP RASC. Samples of soil around pilot area as well as surface water and underground water from public water and from water drains nearest to the pilot road areas were taken for analysis prior to and after the construction of the pilot recycled drill cuttings road to investigate potential leakage and to assess potential environmental impact of the pilot road to the public water. The water analysis results are within acceptable standards in accordance to the Notification of the National Environmental Board. The pilot recycled drill cuttings road project is consulted and endorsed by the Department of Mineral Fuel and is the first implementation on drill cutting waste utilization in Thailand. It offers cost effective and environmentally sound recycling method for drill cutting waste management and serve as example of circular model for exploration and production waste.

Australia introduced conventional longitudinal diamond grinding of highway concrete pavements in 2009 with the purchase of two "4‐foot" highway grinding machines by two contractors. The availability of these machines in Australia has enabled contractors to improve ride quality of new pavements, rather than accept a deduction to the tendered rate for the supply and placement of concrete pavement. Grinding of new concrete base is permitted up to an IRI of 3.5 m/km, thereby reducing the need to remove and replace concrete pavement which met the specified thickness, strength and density, but not ride quality. More importantly, with the introduction of the grinding machines, asset managers have the opportunity to use diamond grinding to treat existing concrete pavements that have a rough ride, or when the textured surface no longer meets specified levels for skid resistance. Although the primary use of diamond grinding was to improve ride quality of new and existing concrete pavements, it has also been used to: treat stepping across transverse contraction joints in PCP, improve skid resistance at roundabouts, improve both ride quality and texture for JRCP pavements (greater than 40 years of age) with a thin wearing course and spalling in the asphalt at transverse joints. The above treatments to concrete pavement allow asset preservation and avoid high reconstruction costs. The Austroads concrete pavement design procedure is based on the PCA design method and road smoothness is not a design parameter, unlike the USA approach to concrete pavement design where ride quality is a design input. There is still much work to be done to convince asset managers in Australia that the removal of the high areas of a concrete pavement to smooth the surface, reduces the dynamic wheel loading and minimises accumulated fatigue stress in the concrete. This paper reviews the last 10 years of diamond grinding projects and the success of this pavement preservation treatment for new and existing urban and rural concrete pavements in Australia. Recommendations to reduce the cost of diamond grinding concrete pavements and extend the use of this treatment are also provided.

The wear prediction of artificial joints is a very difficult task due to several factors. First, one could notice a large domain of joint loading due to the wide spectrum of common activities. Secondary, to account for the evolution of contact conditions due to wearing could imply a high level of nonlinearity and time-consuming algorithms in order to solve. The authors tried to overcome all these difficulties by using a complex predictive model that combines statistical evaluation, nonlinear mechanical analyses of load transfer by the contact interface and tribological estimations of the wear characteristics. After a theoretical description of the predictive model, one could notice an application for an artificial Total Hip Prosthesis — a frictional CoCr alloy on ultra high molecular weight polyethylene (UHMWPE) couple. Several loading regimes are considered as characteristic for the common activity of the patient (normal walking, stair ascending and descending). For every regime a dynamic Finite Element simulation of the frictional contact was performed establishing the contact traces and the contact pressure distribution. Those characteristics combined with the frequencies of the activities considered are input data for computing a special point function which distribution over the contact surface could be a good measure of the wearing regime, qualitatively as quantitatively.

In this work, a model to evaluate the abrasive wear between two semi-cylindrical entities is presented. The entities represent the average roughness radius, of the contact surfaces formed between the femoral head and acetabular cup of a hip prosthesis. The contact couples employed in this work are CrCoMo-UHMWPE and DLC-UHMWPE. Here three different interference distances were employed: 1, 2.5 and 40 percent of the mean radius roughness of the UHMWPE. The energy method proposed here determines the maximum contact stresses, from where the maximum point of distortional energy is obtained. This is then linked to the geometry of the cylindrical entity, which then gives the initial failure point. Subsequent similar calculations provide with the trajectory of the wearing path. The percentage of the abrasive wear obtained from this method was compared to Archard’s method. It was noted that the percentage of Archard’s wear is a ten in million part from the total volume, while that the percentage of Energy’s wear is between 2.760% and 7.055%, when an interference distance S = 0.5 μm, was employed. It was also found that the CrCoMo-UHMWPE couple exhibited 22.84% of volume lost compared with the 2.95% of the DLC-UHMWPE couple.