Determining Geosynthetic Material Properties Pertinent to Reinforced Pavement Design: Fid-Bau Portal

Determining Geosynthetic Material Properties Pertinent to Reinforced Pavement Design

Cuelho, E. V. / Perkins, S. W. / Ganeshan, S. K.

When designing any civil structure, it is necessary to determine the properties of the various material components under conditions pertinent to their eventual use. Geosynthetic reinforced earthen structures are no different. Standard tension tests currently exist to determine basic material properties of geosynthetics used to construct reinforced walls, slopes, embankments and other static structures. However, because these material tests apply slow monotonic loads at room temperature, they may not properly represent conditions pertinent to geosynthetic reinforced pavements. A number of research projects have been conductedn the past to investigate possible differences in material properties using various temperatures, confinements, load types, and strain rates. This research effort conducted an extensive literature review to study the effects of these four parameters on geosynthetic material properties. Additionally, material tests were conducted to determine how cyclic loading affects geosynthetic material properties. Modifications were made to the existing wide-width test protocols (ASTM D4595 for geotextiles, and ASTM D6637 for geogrids) to incorporate cyclic loads. These dynamic wide-width strain-controlled tension tests demonstrated great promise for providing values of elastic material properties. The results from these tests showed that the modulus of the geotextile materials changed at various levels of initial permanent strain, while the modulus of the geogrids remained relatively constant. Future testing will be conducted to further examine similar effects due to temperature, strain rate, load type and confinement.