Run Static Compression Test (ML/QML) for pile foundations, guiding field engineers through load scheduling, settlement measurements, acceptance decisions, and documentation while explicitly excluding constant rate of penetration (CRP) procedures.
- Define ML or QML method, exclude CRP, align with approved plan.
- Set load increments, hold times, and settlement reading intervals.
- Capture calibrated readings, photos, signatures, and traceable data exports.
- Interactive, commentable checklist with export and QR code verification.
The checklist
Pre-Test Planning
- Confirm the selected test method is Maintained Load (ML) or Quick Maintained Load (QML) and explicitly exclude CRP.
- Review approved test plan and project specifications; verify test load (TL) and acceptance criteria are defined and signed off.
- Verify pile identification, cut-off level, and datum; record GPS coordinates and pile head elevation to ±5 mm accuracy with photos.
- Confirm safety controls: exclusion zone, lifting plan, hydraulic hose ratings, and emergency depressurization; document toolbox talk attendance signatures.
Equipment Setup and Calibration
- Check hydraulic jack capacity ≥ 1.2× maximum TL and stroke adequate; attach calibration certificate dated within 6 months.
- Verify load cell or pressure gauge resolution ≤ 1% full scale and calibration traceable; photograph serial numbers and gauges at zero.
- Install at least three settlement gauges (dial or LVDT) with 0.01 mm resolution on an independent reference beam; zero within ±0.02 mm.
- Set reference beam supports outside the influence zone (≥3 pile diameters from test pile); measure beam movement ≤0.1 mm during seating.
Reaction and Alignment
- Verify reaction frame/anchors capacity ≥ 1.25× maximum TL with approved layout; capture proof calculations and as-built photos.
- Align jack and load cell with pile axis; check eccentricity ≤ 3 mm using straightedge/plumb and shim as needed; photo evidence.
Load Schedule and Instrumentation
- Prepare load increments (e.g., 0.25 TL steps to target TL) and unloading sequence per approved plan; record exact kN values.
- Define ML hold criterion (e.g., settlement rate threshold) and QML hold times per approved project specifications; document criteria on sheet.
- Set reading intervals: at each increment record at 0, 1, 2, 4, 8, 15, 30, 45, 60 min (ML) or per QML intervals; time-sync devices to UTC.
- Mark pile head gauge targets; establish temperature log (±1 °C) to support thermal correction if required; photo the setup.
Testing Execution (ML)
- Apply seating load 5–10% TL; verify gauges stable (≤0.1 mm drift over 5 min) before starting first increment; record baseline.
- Load in planned increments using jack and load cell; maintain each increment until ML hold criterion is met; log kN and mm at intervals.
- At maximum TL, hold until settlement rate meets criterion; record creep data and photograph gauge faces and data logger display.
Testing Execution (QML)
- For QML, increase load in increments, holding each for the shorter approved duration or rate criterion; capture readings at defined times.
- Limit load adjustments to ≤5% TL per correction; avoid overshoot >2% of target step; document any corrective actions in comments.
Data Recording and Acceptance
- Unload in decrements to zero; measure rebound at 0, 5, 10, 15, 30, 60 min; compute net settlement and elastic recovery.
- Generate load–settlement curve; apply any specified corrections; compare results to acceptance criteria per approved project specifications and authority requirements.
- Flag nonconformance if criteria are not met; notify stakeholders; plan retest or mitigation per approved procedures; attach NCR reference.
Post-Test and Demobilization
- Depressurize hydraulics gradually; remove reaction and reference beam without disturbing gauges; inspect pile head for damage; photo condition.
- Archive raw data, calibration certs, photos, and signed field sheets; export CSV/PDF; embed QR code for record authentication.
Preview the printable checklist
Preview page one below. Open the image or download the PDF for all pages.
At a glance
- This checklist standardizes ML and QML static compression testing for piles, from method confirmation and load scheduling to settlement measurement, data interpretation, and acceptance aligned with approved project specifications and authority requirements.
- Technicians get precise instructions for instrumentation setup, calibrated load application, reading intervals, and creep/rebound capture. Evidence requirements ensure traceability, including photos of gauges, data exports, and signatures with time-synchronized records.
- Interactive online checklist with tick, comment, and export features secured by QR code.
- Clear acceptance guidance compares measured settlements and creep rates against the approved criteria, helping teams avoid misinterpretation, minimize retests, and deliver reliable capacity assessments suitable for design validation and compliance.
How to Use This ML/QML Static Compression Test Checklist
- Preparation: Review the approved test plan, method (ML or QML), and acceptance criteria. Assemble calibrated jack, load cell/pressure gauge, reference beam, 0.01 mm gauges, temperature logger, PPE, and barricades. Verify reaction capacity and safety controls.
- Site Setup: Position reaction system and reference beam outside the influence zone. Align jack with pile axis, check eccentricity, and zero gauges. Time-sync all devices and photograph serial numbers and initial readings.
- Configure Load Schedule: Define increments, holds, and reading intervals for ML or QML per the approved plan. Record target kN values and overshoot limits before starting.
- Execute Test: Apply seating load, then run increments per schedule. Maintain holds to the defined rate or time criterion. Record settlements, creep, and rebound with photos of instruments.
- Using the Interactive Checklist: Start interactive mode, tick each step as completed, add comments for deviations, and attach photos or data files. Export the running log to PDF/Excel for review.
- Analysis and Acceptance: Build the load–settlement curve, apply specified corrections, and compare results with acceptance criteria. Note pass/fail with rationale and supporting evidence.
- Sign-Off: Capture digital signatures from responsible parties, distribute the report to stakeholders, archive records, and validate authenticity via the embedded QR code.
Purpose, Scope, and Method Selection
Static compression testing verifies pile capacity and load–settlement response under controlled, measured loading. This checklist covers Maintained Load (ML) and Quick Maintained Load (QML) methods only; constant rate of penetration (CRP) is excluded. Use it to plan the load schedule, define hold criteria, and structure settlement measurements in SI units. Selecting ML or QML should reflect geotechnical objectives, schedule, and specification requirements. ML emphasizes time-dependent behavior via longer holds, while QML prioritizes efficiency with shorter stabilization periods. Clear documentation—the approved plan, calibration certificates, and time-synchronized readings—protects data integrity and reduces disputes. Safety controls and reaction design prevent instability and accidental releases. By tightening method selection, evidence capture, and acceptance referencing, you avoid premature unloading, misread gauges, and incomplete creep or rebound data. The result is a defensible curve and a clear pass/fail decision for design validation and compliance.
- Use ML for detailed creep and rebound behavior.
- Use QML for efficient, compliant verification.
- Exclude CRP; do not apply constant penetration rate.
- Synchronize time sources across all instruments.
- Ground decisions in the approved test plan.
Instrumentation, Load Scheduling, and Readings
Accurate settlements depend on stable references and calibrated sensors. Install at least three displacement gauges on an independent reference beam positioned outside the influence zone. Verify jack, load cell, and gauges with current certificates and record serials. Define load increments and holds in the plan, including reading intervals that align with ML or QML methodology. Control overshoot and adjust pressure in small steps to hit target loads. Record baseline readings after seating load, then capture settlements and creep during each stage. At peak load, maintain the hold until the specified rate threshold is met; upon unloading, document rebound at defined times. Photos of gauge faces and data-logger screens support traceability. Temperature logs and beam movement checks help interpret anomalies and filter noise from true settlement response.
- Place reference beam beyond three diameters.
- Gauge resolution 0.01 mm or better.
- Control load overshoot within 2% of target.
- Record creep and rebound explicitly.
- Photograph instruments at each key step.
Acceptance, Reporting, and Evidence Control
Acceptance hinges on comparing the measured load–settlement behavior against the approved project specifications and authority requirements. Generate the curve, compute net settlements, and apply any specified corrections, such as elastic shortening adjustments. Review creep rates, maximum settlements at target load, and recovery on unloading. If the pile passes, compile a signed report with calibrated instrument evidence, time-stamped readings, photos, and data exports. If it fails, issue a nonconformance, notify stakeholders, and plan remedial action or a retest. Use the interactive checklist to add clarifying comments, link calculations, and ensure all deliverables are archived with a QR-verified record. Consistency and completeness reduce disputes and accelerate approvals.
- Compare against approved acceptance criteria.
- Attach certificates, photos, and raw exports.
- Document any deviations with comments.
- Secure signatures and approval routing.
- Archive with QR authentication link.