Has Diamond Grinding Been A Cost Effective Pavement Preservation Treatment In Australia?

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.

Assessment Of Factors Affecting Road Pavement Design And Remedial Actions

Many factors such as number of vehicles, speed, climatic conditions and other factors affect are to be considered for the design of pavement. In this article we will discuss about the factors influencing pavement design. Pavements are engineered structures which are used as roads, runways, parking areas, etc. Ground or surface transportation is the most widely used transportation in the world. So, construction of pavements should be done as it is strong and durable for their design life. There are so many factors which influencing the pavement design. The factors may be of loading, environment, materials used etc. Which are as follows Wheel load, Axle configuration, Contact pressure, Vehicle speed, Repetition of loads, Subgrade type, Temperature and Precipitation. This paper aims to present a review on the performance, problems and possible remedial measures practices for roads constructed on these problematic soils in the country. Finally, emphasis should be given to the importance in construction in this kind of soil of strictly applying engineered design of geometric, drainage, pavement thickness, material selection and proportioning. Thus, those concerned bodies shall decide to accept and control the risk associated with construction on this soil or not, or to decide that more detail study is required to allow for extra design and construction preemptive measures once the potential problem has been identified and the end user convinced of the cost-savings in adopting a pro-active approach.