Improving Reclamation's Field Investigations with the Rock Borehole Direct Shear Test
Can we acquire or develop a rock borehole direct shear test (RBST) device to better determine in-situ strengths for difficult to sample materials that are too strong to be characterized by conventional soil-testing field equipment?
Need and Benefit
Reclamation projects are founded on a variety of materials, from soft soils to hard rock. The materials between "soil" and "rock" are considered to be transition materials that are known to be difficult to sample and characterize. These difficulties result in greater uncertainty in designs of both existing and new structures. Transition materials are often encountered during Reclamation's field investigations and represent significant challenges in terms of sampling and lab testing. Significant resources are often expended to achieve less than ideal results. The RBST device can be used to determine shear strengths of transition materials in-situ. Sites underlain by transition materials are located in all of Reclamation's regions. At this time, the only way to characterize the transition materials is laboratory testing, which may not provide accurate results about field performance.
Contact the Principal Investigator for information about partners.
Bureau of Reclamation Review
The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.
Improving Reclamation’s Field Investigations with the Rock Borehole Direct Shear Test (final, PDF, 1.0MB)
By Evan Lindenbach
Research Product completed on September 30, 2019