ASTRA True Interval Seismic CPT Testing

Calculating shear wave velocity requires recording shear wave travel time between two depths. Traditionally, this meant taking two separate hammer strikes — one for each depth — using a standard seismic CPT testing. With a TRUE INTERVAL SEISMIC CPT TESTING, the process becomes simpler and more precise. Two sensors are positioned EXACTLY 0.5 METERS APART, allowing a SINGLE HAMMER STRIKE to be recorded at both depths at the same time. This design eliminates the variability introduced by multiple strikes, improving data consistency. It also saves valuable time in the field, reducing operator fatigue, and the chance of error. The result: FASTER TESTING, CLEANER DATA, AND GREATER CONFIDENCE IN YOUR SHEAR WAVE VELOCITY CALCULATIONS.

Benefits of Geoprobe^® ASTRA True Interval Seismic CPT Testing 

• Increased accuracy: sensors spaced exactly 0.5 m apart capture waves from the same hammer strike. Real-time software visualization confirms successful strikes in the field.
• Easier in the field: sensors 0.5 meters apart rather than 1 meter increases seismic wave resolution without extra effort. By collecting data from two locations at once, see real-time velocity calculations plotted as pushing cone.
• Simpler set up: swap out one cone section and keep your existing electronics to enjoy true interval seismic simplicity. With a piezotrigger on the shear plate, there’s no need to wire the plate and hammer — whether using traditional or true interval seismic.