​RAM GeoServices specializes in non-destructive testing of deep foundations, employing advanced methods such as Crosshole Sonic Logging (CSL) and Pile Integrity Testing (PIT) to assess the integrity of concrete structures. With a proven track record of evaluating over 5,000 shafts and piles across diverse environments—from Alaska’s subarctic conditions to Arizona’s deserts—we collaborate closely with owners, general contractors, and specialty subcontractors to ensure foundations perform as designed.​

We adhere strictly to ASTM standards, specifically ASTM D6760 for CSL and ASTM D5882 for PIT, ensuring our testing and reporting meet industry benchmarks. Our data interpretation aligns with the latest peer-reviewed guidelines, which often surpass traditional DOT/FHWA specifications. Notably, the 2019 Deep Foundations Institute paper, “Terminology and Evaluation Criteria for Crosshole Sonic Logging (CSL) as Applied to Deep Foundations,” serves as the foundation for defect criteria utilized by leading global CSL equipment manufacturers, including Pile Test (Israel/UK) and PDI (Pyle Dynamics Inc., Cleveland, Ohio).​

By integrating these rigorous standards and advanced testing methodologies, RAM GeoServices delivers precise evaluations of deep foundation integrity, ensuring safety and reliability in every project.

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Terminology and Evaluation Criteria for Crosshole Sonic Logging (CSL) as Applied to Deep Foundations

Summary of the Paper:

Terminology and Evaluation Criteria for Crosshole Sonic Logging (CSL) as Applied to Deep Foundations

This paper, published by the Deep Foundations Institute (DFI) in 2019, provides a comprehensive review of Crosshole Sonic Logging (CSL) testing for deep foundations, including its terminology, evaluation criteria, and best practices for interpretation.

Key Insights:

• Purpose of CSL Testing: CSL is a non-destructive method used to assess the integrity of drilled shafts by identifying anomalies such as voids, soil intrusions, necking, segregation, and other potential defects that could impact structural performance.
• Industry Challenges: Over time, CSL rating criteria have become inconsistent, with variations in acceptance thresholds across regulatory agencies. The paper highlights that first arrival time (FAT) and relative energy measurements, commonly used for shaft acceptance, may not be sufficient alone to determine foundation integrity.
• Updated CSL Rating Criteria: The document introduces a new classification system for CSL results:
  1. Class A (Acceptable): Minor variations that do not affect shaft integrity.
  2. Class B (Conditionally Acceptable): Requires further evaluation but may not necessitate corrective action.
  3. Class C (Highly Abnormal): Requires additional testing, potential remediation, or engineering assessment before acceptance.
• Limitations of CSL Testing: The paper emphasizes that CSL results alone should not be the sole determinant for shaft acceptance. Instead, results should be evaluated alongside construction records, coring, and other non-destructive testing methods to ensure an accurate assessment.
• Industry Recommendations: The authors advocate for adopting standardized CSL interpretation guidelines and integrating them into future industry codes and specifications.

By implementing the recommendations outlined in this paper, engineers and contractors can enhance the reliability of CSL testing, reduce misinterpretations, and improve the long-term performance of deep foundations.