Continuous Surface Wave (CSW): Services from the ground, down

Principle of Operation

The seismic energy source of the continuous surface wave equipment, with operating range of 5-100 Hz, produces surface or ‘Rayleigh’ waves which propagate across the ground surface. These are detected by the system of geophones and analysed by the software. The laptop-based software uses the data to provide a stiffnes vs depth profile. Office based post-processing can provide shear wave velocity profiles, and subsequently mechanical properties of the ground such as shear modulus and elastic (Young’s) modulus.

Design Features

Our Continuous Surface Wave testing equipment provides a detailed, economic method of ground stiffness profiling without the requirement for intrusive works.

The equipment consists of:

• An oscillating seismic energy source or ‘shaker’ capable of frequencies as low as 5Hz  with a 0.1Hz resolution.
• A system of geophone sensors which detect the generated surface waves .
• Control unit and amplifier.
• USB connection to laptop.

Key Benefits

• Provides depth profiling up to 30m.
• Achieves rapid results whilst avoiding invasive testing.
• Enables measurement of ground stiffness with strong correlation to the results of CBR & SPT testing.
• Automated test software allows customisable testing for areas of interest.
• Lightweight and portable.

Technical Information

• Computer Interface: USB Connection
• Data Acquisition: 16 Bit
• Unit Dimensions: 400 x 380 x 150mm
• Seismic Energy Source Dimensions: 450 x 350 x 180mm
• Power: 12-24 VDC or 110 VAC
• Control Unit Weight: 10kg
• Seismic Energy Source Weight: 70kg