A laboratory process to determine the time-dependent increased interface frictional behavior between soil and construction materials

摘要

The increase of frictional resistance is an important aspect to the investigation of increased residual shear strength of such geotechnical projects as landslide remediation, friction pile capacity, and some trenchless technologies. This increase is typically attributed to the dissipation of induced excess pore water pressure, soil aging, or both. Aging has been defined as a time-dependent increase of soil friction angle at a constant effective stress similar to the secondary compression after the primary consolidation and appears to be more prominent in clays than sands. Researchers have used laboratory testing to study the frictional behavior between clay and solid material for many decades. However, the investigation of shear resistance increase at a constant effective stress over time using laboratory experimentation is limited. A simple experimental process has been developed to better identify the behavior of the increase of frictional resistance with time using a standard direct shear device. The procedure introduces a surface of a soil specimen to a sample of construction material to allow the simulation of structure installation and then long-term consolidation prior to testing the interfacial shear strength. The data provided within this study shows that consolidation time as well as OCR increases the frictional strength between soil and concrete.