ASTM Standards for PIT and CSL — A Complete Guide

In deep foundation testing, standards are the backbone of consistency and credibility. Whether you're evaluating a bored pile with pulse echo or using crosshole sonic logging (CSL) in drilled shafts, following globally accepted protocols ensures your data is repeatable, compliant, and defensible. 

Two of the most widely applied standards in this field are ASTM D5882 and ASTM D6760—governing low-strain integrity testing (PIT) and CSL, respectively. If you’re a QA engineer or certification body navigating between methods, specs, and documentation, this guide offers a complete breakdown. 

Explore official documentation and tools from Piletest’s ASTM compliance resources to align your projects with international quality benchmarks. 

1. Why ASTM Standards Matter in Deep Foundation Testing 

Ensuring Repeatability and Transparency 

ASTM standards provide a uniform testing framework so results are: 

· Comparable across projects and teams 

· Auditable by regulators and clients 

· Actionable during inspections or remediation 

For engineers working across multiple job sites—or even across borders—ASTM’s rigor enables confidence in every waveform or signal reviewed. 

Global Acceptance and ISO/EN Harmonization 

ASTM methods are widely accepted across the U.S., Middle East, South America, and parts of Asia. Many are also harmonized with European and ISO standards, enabling consistent QA for international infrastructure projects. 

2. Overview of ASTM D5882 – Low-Strain Integrity Testing (PIT) 

What Is Covered 

ASTM D5882 defines procedures for low-strain integrity tests on deep foundations using a small hammer and sensor on the pile head. The objective is to detect: 

· Cracks or voids 

· Changes in pile cross-section (i.e. Necking, Bulging)

· Pile toe reflections (for length estimation) 

· Suitable for non-slender piles

Required Equipment 

· A lightweight handheld hammer

· A wave sensor (accelerometer) 

· Data acquisition hardware  

· Reflectogram interpretation software 

Wave Interpretation 

A properly executed PIT test yields a clear reflectogram, where changes in signal timing and amplitude reveal potential defects. ASTM D5882 requires clean, flat pile tops and consistent hammer energy to minimize distortion. 

3. Overview of ASTM D6760 – Crosshole Sonic Logging (CSL) 

What It Covers 

ASTM D6760 applies to Crosshole Sonic Logging, used primarily in drilled shafts with embedded access tubes. It uses transmitter-receiver pairs lowered into parallel tubes to send ultrasonic pulses across the shaft. 

What It Detects 

· Flaws and Anomalies between tubes (profiles)

· Defects like

· Voids and inclusions 

· Honeycombing or lack of consolidation 

Test Configuration & Software 

· Access Tube on pile reinforcement cage 30cm apart (usually 3–4 tubes per shaft) 

· Scanning depths and acoustic signal logging between any two access tubes 

· CSL signal analysis and tomography (CHUM system by Piletest is a top tool in this space) 

Visit ASTM D6760’s technical page for deeper insight into these methods and test geometry requirements. 

4. ASTM D5882 vs D6760: Side-by-Side Comparison 

Feature	ASTM D5882 (PIT)	ASTM D6760 (CSL)
Use Case	Integrity of driven or bored piles	Quality control in drilled shafts
Equipment	Hammer, sensor, PC/tablet/smartphone	Access tubes, transducers, CSL hardware and software
Signal Type	Surface wave reflection	Crosshole sonic transmission
Sensitivity	Moderate (good for single  defect in a pile)	High (detects and anomalies with te ability to asses defect shape and volume with tomography)
Prep Required	Clean pile top	Installed access tubes during casting
Key Limitation	Less effective in soft soil damping	Tubes must be installed pre-construction
Result Type	Reflectogram	Waveform speed & energy. Based on FAT (First Arrival Time) and RE (Relative Energy)

These methods are often used together, offering complementary insights. PIT is quicker and lower cost. CSL gives higher resolution data, especially for critical infrastructure. 

5. ISO/EN Equivalents and International Compatibility 

European and ISO Standards 

· AFNOR P160-2,4 – which is equivalnet to ASTM D5882 (PIT)

· AFNOR NF P 94-160-1 which is equivalent tp ASTM D6760 (CSL)

· Definitions vary in waveform interpretation and reporting format 

· Tolerances for anomaly detection and depth increments may differ 

Harmonizing Across Projects 

Global projects often adopt ASTM as a baseline while aligning output formats to regional specs. Using dual-compliant tools makes cross-border QA easier. 

6. Test Protocols, Calibration, and QA Requirements 

Test Protocols for PIT (ASTM D5882) 

· Recommended 3 test points per large diameter pile 

· Averaging of multiple impacts per pile

· Calibrate hammer impact (if instrumented) 

· Optional filtering and sharpening for noisy piles 

· Optional site averaging for referencing values

Test Protocols for CSL (ASTM D6760) 

· 2–4 tubes spaced at equal intervals and not more than 30cm apart 

· Transmitter-receiver lowered simultaneously 

· Full depth scan with overlap zones 

· Interpretation requires trained analysts or CSL software 

Tools That Simplify QA: CHUM CSL System 

Piletest’s CHUM CSL tool includes: 

· 3D tomography 

· Relative Energy in comparison to FAT 

· DFI qualification templates based on FAT and RE

· AGC (automatic Gain Control) of received signal  

7. Reporting Standards and Best Practices 

Required Report Fields (Both Standards) 

· Pile ID and dimensions 

· Pile image and GPS location

· Test date and technician info 

· Signal velocity and settings 

· Annotated waveforms or acoustic logs 

· Ground SPT value and date of pile casting

Format Tips 

· Use locked PDFs for client delivery 

· Include color-coded charts for visual QA 

· Archive raw data for 5–10 years (or per project spec

Traceability 

Use consistent pile IDs across drawings, reports, and logs. Make sure timestamp metadata aligns with site records for auditing. 

Conclusion & Resources 

ASTM D5882 and D6760 provide a solid foundation for quality control in deep foundation construction. From surface reflectograms to crosshole sonic analysis, these methods help engineers and certifiers uphold structural safety and construction quality. 

Use ASTM D5882 tools and D6760 CSL systems to ensure compliance and clarity in every inspection. Need real-time analytics or international-ready reporting? Explore the CHUM system brochure for advanced CSL testing. 

Frequently asked questions

Q1: What’s the main difference between D5882 and D6760?

D5882 is for surface-based wave reflection (PIT), while D6760 involves crosshole logging between embedded access tubes (CSL).

Q2: Are both standards accepted internationally?

Yes, both are widely accepted and partially aligned with EN and ISO standards.

Q3: How often should PIT or CSL devices be calibrated?

Calibration is recommended before major jobs, depending on manufacturer guidance and client requirements.

Q4: Can I run both tests on the same pile?

Not typically. But some do PIT on all for screening and CSL on questionable piles with access tubes.

Q5: What if a test fails ASTM thresholds?

Further investigation is required—usually CSL tomography, excavation, or load testing—depending on flaw severity and project criticality.