Soil Electrical resistivity testing

What is In-situ Electrical Resistivity Testing?

The In-situ Electrical Resistivity Test is a fundamental geophysical method used to investigate the subsurface electrical properties of soil and rock formations. By measuring the electrical resistivity directly at the project site, this test provides valuable insights into soil composition, moisture content, degree of compaction, and the presence of voids or contaminants.

Why Conduct an In-situ Resistivity Test?

• Site Investigation and Characterization: Helps identify different soil layers and their properties.
• Foundation Design: Assists in assessing soil stability and bearing capacity.
• Groundwater Exploration: Detects the presence and flow of groundwater and contaminants.
• Corrosion Assessment: Evaluates the likelihood of corrosion in underground structures.
• Environmental Monitoring: Monitors pollutant migration and contamination spread.

How the Test Works

The test involves injecting electrical current into the ground through a set of electrodes and measuring the resulting potential difference. The resistivity is calculated based on the current, voltage, and electrode configurations. Data is collected at various depths and locations to produce a detailed resistivity profile of the subsurface.

Methods and Equipment Used

• Equipment: Advanced resistivity meters, electrode arrays (e.g., Wenner, Schlumberger, Dipole-Dipole configurations).
• Procedures:
  • Site preparation and electrode installation.
  • Sequential measurements at different depths and positions.
  • Data logging and real-time analysis.
• Data Interpretation: Utilizing software to generate resistivity profiles and maps.

Applications of In-situ Resistivity Testing

• Site characterization for construction projects
• Assessing ground suitability and geotechnical properties
• Locating underground utilities and voids
• Monitoring environmental pollution and remediation
• Groundwater probing and hydrogeological studies

Benefits of In-situ Resistivity Testing

• Non-Destructive: No excavation or extensive disturbance.
• Cost-Effective: Reduces the need for extensive drilling.
• Rapid Data Collection: Provides near real-time results.
• Versatile: Applicable to various soil and rock types.