5.1 The rolling wheel load test is primarily intended as a performance test to quantify the benefits of geosynthetics in pavement structures as recommended by AASHTO R 50-09. Performance is predominantly defined in terms of TBR.

5.2 This test is used to accelerate rutting in a roadway cross section using a rolling wheel. The results from similarly constructed rolling wheel load tests are useful to evaluate and compare the performance of various products or designs. The results from these tests are most relevant to roads having similar design characteristics (material strengths and thicknesses). The extrapolation of results to designs that deviate significantly from the parameters tested may not be accurate, and performance calculations made at significantly different traffic levels than the expected service life of an actual pavement may not provide an accurate estimate of the benefits actually realized.

5.3 The number of traffic passes applied by the trafficking system can be designed to correspond to the number of equivalent single-axle loads (ESALs) used in the AASHTO 1993 pavement design equation, provided it uses load, wheel sizes, and tire pressures associated with that design method.

5.4 The test method is applicable to geosynthetics and construction materials used in typical pavement applications.

5.5 This test method produces test data that can be used to compare geosynthetic products, construction methods, and cross section configurations used in the design of roads and other paved or unpaved structures.

5.6 This test can be used to characterize specific behaviors of the geosynthetic under the conditions tested by including sensors to measure stresses and strains within the pavement cross section or on the geosynthetic itself. Sensors should be appropriately sized and installed to minimize their influence on the test results.

5.7 The relationship between traffic passes and deformation is a function of the composite stiffness of the constructed system and the interdependence between the individual components of the design.

1.1 This standard practice outlines the requirements associated with the construction and testing of full-scale unpaved and paved roadway cross sections, with and without geosynthetics, that are built in a controlled manner and trafficked using a rolling wheel load.

1.2 Test section performance from these tests is normally calculated as a function of life extension, but can also be determined based on structural improvement. Life extension is related to the number of traffic passes that can be accommodated by a particular configuration when compared to a similarly constructed control. Structural improvements are based on elemental or system-wide stiffness increases.

1.3 The rolling wheel load test is intended to be a performance test conducted as closely as possible to as-built unpaved and paved roadway cross sections. It has been used as a tool to compare the performance of different geosynthetics using the same traffic conditions for various conditions, such as soil types, material strengths, layer thicknesses, and construction procedures for a variety of pavement applications.

1.4 Units—The values stated in SI units are to be regarded as the standard. Values in parentheses are for information only.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.