In order to minimise the cost of constructing low volume roads (LVRs), it is essential that optimum use is made of locally available, naturally occurring materials. However, conflicts often arise between material acce...In order to minimise the cost of constructing low volume roads (LVRs), it is essential that optimum use is made of locally available, naturally occurring materials. However, conflicts often arise between material acceptability, as defined by conventional test methods and specifications, and material suitability in terms of actual engineering performance as a “fit-for-purpose” road construction material. To avoid such conflicts, it is crucial to adopt appropriate test methods and specifications for selecting construction materials. This paper presents a materials evaluation framework for optimizing the utilisation of materials in LVR pavements based on the use of the Dynamic Cone Penetrometer (DCP). This approach enables materials to be selected on the basis of their “fitness-for-purpose”. It avoids suitable materials from being rejected based on one or other of the traditionally specified parameters not being complied with, even though their strength, as measured by the DCP penetration rate (DN value in mm/blow) of the soil, may be adequate. Investigations of the properties of a wide range of locally available materials that have been used successfully in the construction of LVRs have confirmed the validity of the materials evaluation framework.展开更多
Widespread implementation of the DCP-DN design method for low volume roads has been promoted internationally over the past decade or so. The method has progressed from a simple determination of the in situ CBR investi...Widespread implementation of the DCP-DN design method for low volume roads has been promoted internationally over the past decade or so. The method has progressed from a simple determination of the in situ CBR investigation based on DCP-CBR correlations with respective cover requirements to a more sophisticated method using the DCP penetration data directly and omitting any need to use correlations with the CBR. This paper summarises the development of the method, and some of its advantages and compares the design structures with other recognised and widely implemented designs.展开更多
文摘In order to minimise the cost of constructing low volume roads (LVRs), it is essential that optimum use is made of locally available, naturally occurring materials. However, conflicts often arise between material acceptability, as defined by conventional test methods and specifications, and material suitability in terms of actual engineering performance as a “fit-for-purpose” road construction material. To avoid such conflicts, it is crucial to adopt appropriate test methods and specifications for selecting construction materials. This paper presents a materials evaluation framework for optimizing the utilisation of materials in LVR pavements based on the use of the Dynamic Cone Penetrometer (DCP). This approach enables materials to be selected on the basis of their “fitness-for-purpose”. It avoids suitable materials from being rejected based on one or other of the traditionally specified parameters not being complied with, even though their strength, as measured by the DCP penetration rate (DN value in mm/blow) of the soil, may be adequate. Investigations of the properties of a wide range of locally available materials that have been used successfully in the construction of LVRs have confirmed the validity of the materials evaluation framework.
文摘Widespread implementation of the DCP-DN design method for low volume roads has been promoted internationally over the past decade or so. The method has progressed from a simple determination of the in situ CBR investigation based on DCP-CBR correlations with respective cover requirements to a more sophisticated method using the DCP penetration data directly and omitting any need to use correlations with the CBR. This paper summarises the development of the method, and some of its advantages and compares the design structures with other recognised and widely implemented designs.