Constitutive Modelling of Joints under Cyclic Loading. Part 3. Cyclic Multi Degree-of-Freedom Shear Device with Pore Water Pressure
Abstract
The previous device described in Part 1 of this Final Report allowed testing of joints and interfaces under dry conditions. This device needed certain modifications such as inclusion of pore water pressure, need to reduce or avoid moment effects due to the eccentricity of the normal and shear loads, need to increase the loading capacity, and need to install devices to measure pore water pressures at the joints and additional devices to measure displacements and stresses. Thus a new loading frame and circular test device were designed and fabricated. This brief report describes details of the frame, test device and electronic control and data acquisition system. The newly developed dynamic direct-shear device is designed to hold an 7.5-inch diameter 3-inch thick upper sample and a 9-inch diameter 3-inch thick lower sample. As the lower sample is larger than the upper sample, the interface area always remains constant during the test. A normal stress of 400 psi (2.7 MPa) and a shear stress of 550 psi (3.9 MPa) can be applied and developed at the interface. Both of these stresses may be increased by modification of the device. The horizontal actuator attaches right at the level of the interface so no significant moment is induced at the interface by the push or pull of the top box. Keywords: Computers, Control systems, Hydraulic systems, Friction, Test equipment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1988
- Accession Number
- ADA200234
Entities
Organizations
- University of Arizona