The GDS Back Pressured Shearbox (BPS) is used
for direct shear testing on soil specimens with varying degrees of
pore pressure by controlling the back pressure of the specimen.
The complete system runs using GDSLAB control and data acquisition
software. This allows standard direct shear tests to be carried out
as well as advanced unsaturated tests under computer control.
An unsaturated version is available where both the pore water and pore air pressures of
the specimen may be controlled. The unsaturated BPS is based on a
saturated back pressured direct shear device,
modified to allow the measurement and control of matric suction (the
difference between the pore air and water pressures).
Download full
specification datasheet as
pdf
[219kb]
GDSLAB software
for GDSBPS video introduction
click
here...
Related
link:
Durham University (UK) video on Research
TV website using the GDS back pressured shearbox to
predict lansdslides
click
here for more...
What are its
uses
Control parameters include:
Shear force and displacement
Effective stress control
Total stress control
Axial (normal) force and displacement
(with
optional axial actuator)
Pore water (back) pressures
Pore air pressures (unsaturated version)
Overview of
features
The GDS BPS is unique to GDS.
The system can be supplied as a
complete, ready to-test system.
The GDS BPS is fully integrated into
and supported by GDSLAB.
GDS can customise most products to
match the required specification
Flexible data output which can be
imported directly into Microsoft® Excel.
Developed from a design brief from the
University of Durham, UK (saturated version) and Dr Liangtong
Zhang of Zhejiang
University, China (unsaturated version).
GDS
Instruments is an ISO 9001:2000 credited company.
