Downhole Seismic Test

Downhole seismic testing is a geophysical method used to measure the seismic wave velocities (P-wave and S-wave) of subsurface materials at different depths. This test is crucial for site-specific seismic design, ground response analysis, and soil classification in accordance with international codes. The process involves placing geophones in a borehole and generating seismic waves at the surface to record their travel times through soil and rock layers. The data helps determine dynamic soil properties needed for earthquake-resistant structural design.

Key aspects include:

• Measures P-wave (compressional) and S-wave (shear) velocities
• Performed using a vertical borehole with downhole geophones
• Supports seismic site classification (e.g., as per Eurocode 8, IBC)
• Determines soil stiffness and dynamic properties
• Essential for ground response and liquefaction analysis
• Accurate, depth-specific data for seismic and geotechnical design