Testing and Modeling the Behavior of Riverbed and Blasted Quarried Rockfill Materials

Abstract

Modeled rockfill materials were obtained from nine sites (two riverbed and seven quarried) from different projects in India and Nepal, and drained triaxial tests were conducted with specimens that were 381 mm in diameter and 813 mm high. Index properties of the rockfill materials, namely, unconfined compressive strength (UCS) and uncompacted void content (UVC), were determined. An elastoplastic hierarchical singe-surface (HISS) constitutive model was used to characterize the behavior of modeled rockfill materials. The predicted stress-strain-volume change behavior was compared with the observed behavior, and it was found that both observed and predicted behavior matched closely. Procedures have been developed to predict the shear strength and elastic parameters of rockfill materials using the index properties, namely, UCS, UVC, and relative density (RD), and predictions were made satisfactorily. Predicted shear strength and elastic parameters were compared with the experimental values, and it was observed that both values matched closely. Then these procedures were used to predict the elastic and shear strength parameters of large-size prototype rockfill materials. Relationships were also developed between index properties and strength parameters of modeled rockfill materials and were used to predict the strength parameters for the prototype rockfill materials. Using the predicted material parameters, the stress-strain-volume change behavior of prototype rockfill material was predicted using the elastoplastic HISS constitutive model.