Top PDF Assessment of Skid Resistance of Road Pavements

Assessment of Skid Resistance of Road Pavements

Assessment of Skid Resistance of Road Pavements

Abstract. The quality of the paved road depends not only on the decisions of the road designer and the work carried out but also on the materials used. Most of the aggregates used are imported from other countries. However, the usage of domestic materials reduces the cost of the road pavement and the use of aggregates produced by a special production technology in Lithuania, i.e., dolomite aggregates instead of granite aggregates. Experimental studies were carried out on the skid resistance of the road surface. It was found that the coefficient of skid resistance met the requirements for surface dressing with dolomite aggregate, and the results were analysed with 95% probability. This coefficient partially met the requirements for asphalt concrete, while it did not meet the requirements at all for stone mastic asphalt. The surface roughness, however, met the requirements for road sections where granite aggregates were used instead of dolomite in mixes of surface dressing and asphalt concrete. The analysis was carried out considering the volume of traffic and the service life of the individual road sections. It was determined that it was suitable for a 5-year guarantee period to perform the surface dressing, wearing course of asphalt concrete and stone mastic asphalt with dolomite aggregate where part of heavy vehicles is less than 20% of traffic flow. The use of granite aggregates was justified only in the road where heavy vehicles dominated.
Show more

12 Read more

An experimental-based model for the assessment of the mechanical properties of road pavements using ground-penetrating radar

An experimental-based model for the assessment of the mechanical properties of road pavements using ground-penetrating radar

Tests for the collection of ground-truth data of pavement stiffness are carried out using the LFWD 218. Prima 100 manufactured by Carl Bro Pavement Consultants Kolding[r]

28 Read more

New apparatus for skid testing : assessment for dusty surfaces

New apparatus for skid testing : assessment for dusty surfaces

Skid resistance act as a friction force when a vehicle moves. It is an important property for safe maneuver of vehicles. The effect of dust surface on the road surface is highly significance to motorcycle where its maneuver depends largely on the balance and stability of the friction force. Riding hazard occurs when motorcycle is side by side with a large vehicle. Large vehicle would travel near center of the road thus motorcycle is force to ride along the dusty path. A slight skidding would end up with an injuries accident. Although there is no actual statistical count of such accident or those slight injuries caused by own crash, the risk of hazard is not to be underestimated. The skid resistance property is controlled by both the pavement and tyre of vehicle. The contact surfaces of both become the key to skid property. Thus, it is of highly importance to identify the effect of dust on road surface toward the skidding resistance property.
Show more

49 Read more

Impact of Volcanic Ash on Road and Airfield Surface Skid Resistance

Impact of Volcanic Ash on Road and Airfield Surface Skid Resistance

Most studies of exposed critical infrastructure have generally focussed on very large eruptions and ashfall deposits >10 mm thick, rarely reporting the effects from ashfall <10 mm thick [10]. This presents a source of uncertainty for emergency management planning and loss assessment models, which is important, as thin deposits are more frequent and often cover larger areas [15]. Some notable eruptions that have led to reported reduced skid resistance on roads in the past are highlighted in Table 1. It has been suggested that impacts start at ~2-3 mm ash thickness [2], although there have been few studies that have quantified such impacts in detail. Indeed, the limited quantitative data available from historic observations generally relates impacts to approximate depths of ash, which may not be the best metric: ash characteristics such as particle size, ash type, degree of soluble components and wetness, may influence or even control the level of skid resistance. We investigate the importance of these alternative characteristics in this paper.
Show more

39 Read more

Soil stabilisation in road pavements

Soil stabilisation in road pavements

Following test pits conducted by RMS geotechnical branch it was recommended that the pavement be rehabilitated using insitu lime stabilisation combined with imported unbound granular material for an overlay. The final design included a 120mm unbound granular overlay with material that met RMS material specification 3051 for a traffic category of B (Design number of Equivalent Standard Axles, DESA), and a depth of stabilisation of 200mm with 3% lime additive. It was also noted in the design brief that the associated road pavement repair is were to provide a desirable 20 year design life, however this may be governed a cost assessment. Due to geotechnical recommendations and financial constraints, the project was divided up into three sections of 700m, 500m and 250m across a 2.5km stretch to target the pavement areas of highest priority. This project was resourced utilising a mixture of RMS direct control resources and sub-contractors.
Show more

103 Read more

Estimating and Reducing the Release of Greenhouse Gases in Local Road Pavement Constructions

Estimating and Reducing the Release of Greenhouse Gases in Local Road Pavement Constructions

Abstract— Local roads, which comprise 91% of the road networks in Indonesia, are a vital part of the transportation infrastructure. The construction of local roads has had some negative impacts on the environment, one of the most significant of which is the release of greenhouse gases (GHG). In order to develop a strategy for sustainable development in transportation infrastructure, it is essential that GHG emissions be reduced in the local road construction cycle. The aims of this study were to estimate the release of GHG and to elaborate on efforts to reduce GHG emissions in the construction of both rigid and flexible local road pavements. First, a life cycle assessment was performed to calculate the energy consumption and amount of GHG emissions. Next, some possible approaches were explored and elaborated on to seek opportunities to reduce GHG emissions, and therefore, enhance the sustainability of local road constructions. The results showed that material processing and material transportation contributed to 74.0-75.2% and 24.7-26.5% of GHG emissions, respectively. It is also known from the stepwise analysis that the significant predictor to form the amount of GHG both on the rigid and flexible pavement is the distance of the aggregate source to batching/asphalt mixing plant. Hence, the strategies for the reduction of GHG emissions, in this case, might be carried out by substituting current construction materials (cement and asphalt) with less intensive GHG emissions materials, and by reducing the distance for the transportation of the aggregates. The result shows that the first proposed strategy, which is substituting cement or asphalt with fly ash and reclaimed asphalt reduces more GHG than the second one.
Show more

7 Read more

Pavement Friction and Skid Resistance Measurement Methods: A Literature Review

Pavement Friction and Skid Resistance Measurement Methods: A Literature Review

Although there are multiple causative factors involved in highway accidents, investiga- tions on factors influence traffic accidents, have consistently shown a link between crashes and pavement surface characteristics, such as friction and texture. Thus, for developing effective solutions to reduce potentially hazardous situations, there is a re- quirement for depth studies on these parameters and understanding the relationship between them [1]. Pavement surface friction is a measure of safety for driving on the road pavements and has a great role in reducing accidents especially in wet weather conditions [2]-[4]. An essential part of the vehicle-pavement interaction is friction force between the tire and the pavement surface. It gives the vehicle the ability to have safe acceleration, maneuver, corner, and stop operations [5]. The friction force devel- oped at the contact zone between tire and pavement is called skid resistance [6]. The skid resistance is related to many factors and it is known to be a function of pavement construction materials [7] [8], pavement roughness [9], and surface conditions [10].
Show more

29 Read more

Effect of Pavement Friction Factors on Skid Resistance of Highway Pavements using Prediction Models

Effect of Pavement Friction Factors on Skid Resistance of Highway Pavements using Prediction Models

Due to the high association among the road skid resistance and collision percentage, it necessitates an enhanced system for all-inclusive material selection and admixture design. The mixture designers are constantly encountered with the task of choosing the proper aggregates. Moreover, it is essential to acknowledge the frictional traits of aggregates and their capability to endure the refining act of the ensuing traffic [17]. Taking into consideration these significant features, they prevent the possibility of extra expenses for surface management. The preservation and restoration budget of pavements may be minimized through enhancement of an all-inclusive structure for aggregate selection established on a quantitative assessment of the physical attributes of aggregate correlated to the skid resistance of the road [17]. Accordingly, the skid number does not signify the halting features of the vehicle, motorist, or weather conditions, nevertheless, it is an advantageous tool that can be utilized in assessing the surface friction traits depending on the aggregate forms, asphalt mixture design and the road structure techniques [18].
Show more

7 Read more

The Effect Of Surface Texture On Skid Resistance Of Asphalt Pavements

The Effect Of Surface Texture On Skid Resistance Of Asphalt Pavements

Studies by Kamel and Musgrove (1981) revealed that some 54 percent reduction of accidents in wet weather and about 29 percent reduction on total were possible when a pavement of high skid resistance was used. This fact was seconded by Masad et al. (2007). It is also known from the studies, that the skid resistance of a pavement surface is associated with two main characteristic properties, and they are the microtexture and the macrotexture of the pavement. Briefly, it can be said that microtexture depends mainly on the aggregate shape, its characteristics, mineralogy, and the macrotexture is dependent on mix properties, aggregate gradation, etc. (Masad et al., 2007). The Macrotexture of the pavement surface is held as one of the prominent contributory Abstract: One of the most important factors contributing to road traffic accidents in today’s busy world is lack of adequate skid resistance on roads. Adequate friction at road-tyre interface reduces skidding in both wet and dry weather conditions. As typical maintenance policies are costly and disruptive, the situation cries out to construct pavements sufficiently skid resistant in the first place. This thesis analyses the influence of Mean Texture Depth (MTD), aggregate size, spacing between aggregates (edge-to-edge), on Skid Resistance. Finally, the effect of friction on Braking Distance was investigated. Additionally, the influence of varying void contents is considered. British Pendulum Test and Sand Patch Test were performed to account for micro and macrotexture of the samples respectively. The research used asphalt concrete slabs manufactured in the laboratory with varying void content and cores from a certified engineering company. The results are presented and analyzed. In most of the cases, the cores produced justifiable results, where Skid Resistance in terms of both MTD and friction coefficient decreased with increasing spacing (edge-to-edge) and decreasing aggregate size. But, the results obtained in some cases while studying the slabs were not as expected.
Show more

19 Read more

The determination of the texture depth, skidding resistance and roughness index of various bituminous road surfaces

The determination of the texture depth, skidding resistance and roughness index of various bituminous road surfaces

Generally the road pavement structure is classified into the sub-grade, sub- base, road base and the surfacing which consist of binding course and wearing course. The wearing course is the exposed topmost layer that provides the travel path, skid resistance, safety and comfort to the road user. In view of this the study investigated specifically the pavement surface frictional characteristics, skid resistance, texture depth and the International roughness index of these categories of bitumen pavements, ACW14, ACW20, SMA14and surface dressed surfaces.
Show more

18 Read more

Pavement Evaluation of the Nairobi Eastern By-Pass Road

Pavement Evaluation of the Nairobi Eastern By-Pass Road

A detailed visual condition survey was undertaken on each travelling lanes. Table 5 gives a summary of the visual data collected with respect to the various homogenous sections. The results show that none of the sections had visible pot holes, cracks or unchecked drainage. The average visual condition survey (VCS) index was 0.0 implying that the visual characteristic of the road was generally in a good condition and could be remedied through regular light maintenance. However, although there was no section with serious visible distresses, the averages of the speed among the sections differed significantly with some sections having average speed of as high as 63.0 kph for homogenous section 8 and as low as 31.8kph in section 12 of the road.
Show more

8 Read more

The Effects of Road and Other Pavement Materials on Urban Heat Island (A Case Study of Port Harcourt City)

The Effects of Road and Other Pavement Materials on Urban Heat Island (A Case Study of Port Harcourt City)

The research suggests that further research should focus on other aspects of the environment such as Flora and fauna. The impacts of urban heat island on urban residents especially in the study area are enormous as its com- bined effect with the global change in temperature has exacerbated impact on residents of the city of Port Har- court. There has been reported cases of heat rashes epidemic, psychological restlessness as a result of excessive heat at night and day and increased ground level ozone. The research recommends the review of the Port Har- court Master plan or a total urban renewal programme in the city of Port Harcourt to incorporate more green- belts and open spaces for planting of tree instead of pavements and concreted areas. This will create a conducive environment for work and for living. It will also reduce the effects of (UHI) and ultimately improve the comfort and living conditions of the residents of the city.
Show more

13 Read more

Life Cycle Cost Analysis of Flexible Pavements and Rigid Pavements in Urban Areas

Life Cycle Cost Analysis of Flexible Pavements and Rigid Pavements in Urban Areas

In this study the cost required for initial construction and for maintenance of the pavements is calculated by using net present value method of life cycle cost analysis. IRC SP-30 (2009) gives the formula for net present value. Agency costs are calculated from the district schedule of rates of Public Works Department (PWD) Pune region. The procedures of

7 Read more

Polymeric Waste Material In Concrete For Road Pavements

Polymeric Waste Material In Concrete For Road Pavements

better performance over a period of time. Waste plastic such as carry bags, disposable cups and laminated pouches like chips, pan masala, aluminum foil and packaging material used for biscuits, chocolates, milk and grocery items can be used for surfacing roads.Use of plastic along with the bitumen in construction of roads not only increases its life and smoothness but also makes it economically sound and environment friendly. Plastic waste is used as modifier of bitumen to improve some of bitumen properties Roads that are constructed using plastic waste are known as Plastic Roads and are found to perform better compared to those constructed with conventional bitumen. Further it has been found that such roads were not subjected to stripping when come in contact with water. Use of higher percentage of plastic waste reduces the need of bitumen by 10%. It also increases the strength and performance of the road.
Show more

9 Read more

The erosion of the form and quality of central Hobart's spaces : planning for repair

The erosion of the form and quality of central Hobart's spaces : planning for repair

•Road Pavements The major streets within the study area, particularly Collins, Elizabeth, Liverpool and Murray, that delineate the central city block should have the road pavement width [r]

162 Read more

 Reducing erosion from forest roads and skid trails by management practices

 Reducing erosion from forest roads and skid trails by management practices

affecting surface erosion on roads and skid trails is climate such as rainfall intensity and duration, snowfall, wind etc. (Byblyuk et al. 2010; Fu et al. 2010). Other factors that can affect erosion are the quality of forest road surfacing material (asphalt road surfacing with the lowest effect and native road surfacing with ruts with the highest effect on erosion and with the 0.03 and 2 surfacing factors, respectively) and traffic (main highway and blocked road with the traffic factors of 120 and 0.1, respec- tively) especially during wet weather (Akay et al. 2008; Khalipoor et al. 2008). Also, slope steep- ness is an important factor in soil erosion by water. Steep roads and skid trails lead to greater erosion rates (Luce, Black 2001; Sidle et al. 2006; Bybly- uk et al. 2010; Fu et al. 2010). Slope length also has a significant role in erosion. As Luce and Black (1999) found out, an increase in both road length and gradient can lead to increased erosion. They stated that erosion is proportional to the product of road length and the square of slope (E~LS 2 ). Fi-
Show more

5 Read more

The Effect of Asphalt Concrete Micro & Macro Texture on Skid Resistance

The Effect of Asphalt Concrete Micro & Macro Texture on Skid Resistance

Accepted: 5 January 2013 Skid resistance and road condition are common indices of road safety; therefore providing adequate skidding resistance will reduce the incidence of road accidents. The surface macrotexture has a large effect on the characteristics of road surface skidding, which is the focus of this research. During the study, the mean texture depth of the road surface was measured, in order to determine the conditions that ensure the maximum contact area between the vehicle tires and road surface during wet conditions. The Pavement Guideline No. 234 was consulted for the test procedure and road surface composition, which used open and dense graded crushed lime aggregates with varying percentages of bitumen applied to the mix design. The samples were then tested to assess their stability using the Marshall and Gyratory Tests. The results showed that with the application and evaluation of the sand patch method, where the effect of the macrotexture on skidding resistance was analyzed with various gradations, there was an improved higher skidding resistance and a subsequent projected reduction of accidents with an increased safety.
Show more

14 Read more

Investigations of factors affecting pendulum test value on asphaltic concrete surfaces

Investigations of factors affecting pendulum test value on asphaltic concrete surfaces

One major factor contributes to road accident is skidding as there is connection between vehicle tyre and pavement. The worst skidding ever happen is during wet pavement condition during rainy day. Besides that, a research shows that skidding contributes to 25% of wet road accidents in United Kingdom (Kennedy et al., 1990).

20 Read more

<p>Phenotypic and Genotypic Assessment of Antibiotic Resistance of <em>Staphylococcus aureus</em> Bacteria Isolated from Retail Meat</p>

<p>Phenotypic and Genotypic Assessment of Antibiotic Resistance of <em>Staphylococcus aureus</em> Bacteria Isolated from Retail Meat</p>

Results: Forty-eight out of 485 (9.89%) raw retail meat samples were contaminated with S. aureus. Raw retail buffalo meat (16%) had the highest incidence of S. aureus, while raw camel meat (4%) had the lowest. S. aureus bacteria exhibited the uppermost incidence of resistance toward tetracycline (79.16%), penicillin (72.91%), gentamicin (60.41%), and doxycycline (41.666%). The incidence of resistance toward chloramphenicol (8.33%), levo- fl oxacin (22.91%), rifampin (22.91%), and azithromycin (25%) was lower than other exam- ined antibiotics. The most routinely detected antibiotic resistance genes were blaZ (58.33%), tetK (52.08%), aacA-D (33.33%), and ermA (27.08%). Cat1 (4.16%), rpoB (10.41%), msrA (12.50%), grlA (12.50%), linA (14.58%), and dfrA1 (16.66%) had the lower incidence rate. Conclusion: Raw meat of animals may be sources of resistant S. aureus which pose a hygienic threat about the consumption of raw meat. Nevertheless, further investigations are essential to understand supplementary epidemiological features of S. aureus in retail meat.
Show more

11 Read more

Fly Ash (F - Class): Oppertiunities For Sustainable Development Of Low Cost Rural Roads

Fly Ash (F - Class): Oppertiunities For Sustainable Development Of Low Cost Rural Roads

[5] Guru vittal u. k., scientist satander kumar scientist, deepchandra, head sr div. dr. p. k. sikadar, Director Central Road Research Institute New Delhi."Utilization of fly ash in road construction". CE and CR April 99 Pp 60-63. Rigid Pavement Division, Maharashtra Engineer's Research Institute Nashik "Study of fly ash samples from Eklahre Thermal Power Station".

6 Read more

Show all 10000 documents...