The Spectral Analysis of Surface Waves (SASW)
system provides compact, lightweight and easy-to use equipment for
the analysis of surface waves. It allows fast, non-invasive testing
for all soil types, including residual soils and fractured soft
rock. Typically used in site
investigations for foundation engineering design and settlement
prediction, SASW is also suited for the rapid sub-grade evaluation
for roads, tracks and runways.
Download full
specification datasheet as
pdf
[274kb]
What are its
uses
The system performs an on-line Fast Fourier Transform (FFT) on the
acquired data with automatic stacking and trigger arming allowing
for as many as 15 separate records per minute to be acquired for a
single test. The stacked data can be manually or automatically
‘picked’ to create an on-line stiffness v depth plot. The GDS SASW
system uses impulse or transient energy sources to measure the
seismic wave velocity. A variety of energy sources may be used, for
example.
Hammers or drop weights using the
accurate remote triggering facility.
Non-user controlled energy sources (eg
dynamic compaction rig) may be triggered manually from the control
unit.
The GDS SASW system is based on the GDS Surface Wave Control Unit
which is also configured for use as the main control unit for the
GDS Continuous Surface Wave
System (CSWS). The CSWS uses a vibrating energy source run at single
frequencies under the control of the unit.
New for
Version III
Simultaneous sampling of all channels
Designed to be more ruggedised/robust
Smaller and lighter (version III
weighs only 5.5kg).
Greater power efficiency
GDS
Instruments is an ISO 9001:2000 credited company.
