Proof Load Testing
Non-Destructive Verification of Post-Installed Anchor Performance
Proof load testing is a non-destructive test that verifies the correct installation of post-installed anchors by applying a controlled load to a predetermined proof load value. The proof load is typically 1.5 times the serviceability load per VicRoads Section 680, or calculated per BS 8539:2012+A1:2021 Annex B.3. The load is held for a minimum of 30 seconds and must not drop more than 10% during the hold period — any drop exceeding this threshold indicates a potential installation defect or substrate inadequacy requiring investigation.
Proof load testing is the primary quality assurance mechanism for safety-critical anchoring applications where failure could cause injury, structural collapse, or significant economic loss. Unlike ultimate load testing, proof testing does not damage the anchor — it confirms that the installed anchor can sustain its design load with adequate margin, and the anchor remains serviceable after testing. This makes proof testing the standard for production anchors that will remain in service.
ATA conducts proof load testing in both confined and unconfined configurations. Confined testing uses a reaction frame that bears on the concrete surface near the anchor, which restrains the concrete cone and produces higher apparent capacities. Unconfined testing uses a reaction frame with a clear span exceeding the concrete cone diameter, allowing the full failure mechanism to develop. The choice between confined and unconfined configuration is an engineering decision that depends on the in-service loading condition — ATA specifies the appropriate configuration based on the actual application geometry per AEFAC TN05 Volume 2.
Every proof load test is documented with applied load, hold duration, load decay during hold, and pass/fail determination against the specified acceptance criteria. Where displacement monitoring is specified, anchor movement under load is recorded simultaneously. ATA provides RPEQ-reviewed test reports that include test methodology, acceptance criteria derivation, individual test results, and statistical summary — the complete evidentiary basis for anchor acceptance or rejection.
Speak with an RPEQ-qualified structural engineer about this service.
Capabilities
Tension Proof Load Testing (Pull-Out)
Hydraulic application of axial tension load to post-installed anchors. Calibrated hollow-core hydraulic jacks with certified load cells. Load applied incrementally to proof load value per VicRoads Section 680 or BS 8539 Annex B.3.
Shear Proof Load Testing
Application of shear load to installed anchors using purpose-built shear loading apparatus. Required where the primary in-service load is shear rather than tension, or where combined tension-shear interaction must be verified.
Confined & Unconfined Test Configuration
Selection and setup of appropriate test configuration based on in-service loading geometry. Confined configuration for anchors loaded near edges or in groups; unconfined configuration for isolated anchors loaded away from edges, per AEFAC TN05 Vol 2.
Proof Load Derivation & Acceptance Criteria
Engineering derivation of proof load values from design loads, including safety factors per VicRoads Table 680.091, BS 8539 Annex B.3, or project-specific requirements. Written acceptance criteria issued before testing commences.
Calibrated Equipment with Current Certification
All hydraulic jacks, load cells, and pressure gauges carry current NATA-traceable calibration certificates. Calibration records are included in every test report as part of the quality assurance documentation.
On-Site Testing with Minimal Disruption
Portable testing equipment designed for site deployment. Testing conducted on active construction sites, operational buildings, and infrastructure with access coordination to minimise programme impact.
RPEQ-Reviewed Test Reports
Comprehensive test reports documenting methodology, acceptance criteria, individual test results, statistical analysis, and pass/fail determination. All reports reviewed by an RPEQ-qualified structural engineer.
Test Quantity Determination per Standards
Engineering determination of required test quantities per VicRoads Table 680.091 (percentage-based sampling) or BS 8539 (statistical method requiring minimum 15 tests, or simplified method requiring 5 tests). Quantity scaled to consequence of failure.
Frequently Asked Questions
What is proof load testing and when is it required?
Proof load testing is a non-destructive test that verifies the correct installation of a post-installed anchor by loading it to a predetermined proof load — typically 1.5 times the serviceability load. It is required for safety-critical applications per AS 5216:2021, where failure could result in injury, structural collapse, or significant economic loss. VicRoads Section 680 and AEFAC TN05 provide specific guidance on when proof testing is mandatory, including anchors supporting structural connections, façade systems, and overhead installations.
What is the difference between confined and unconfined testing?
In a confined test, the reaction frame bears on the concrete surface close to the anchor, which restrains the concrete cone failure mechanism and produces higher apparent capacities. In an unconfined test, the reaction frame spans beyond the concrete cone diameter, allowing the full failure mechanism to develop. Unconfined testing produces lower but more conservative results. The choice depends on the in-service loading condition — AEFAC TN05 Vol 2 provides guidance on selecting the appropriate configuration based on how the anchor is actually loaded in the structure.
How many anchors need to be proof tested?
Test quantity depends on the applicable standard and the consequence of failure. VicRoads Table 680.091 specifies percentage-based sampling rates that increase with consequence classification. BS 8539 requires a minimum of 15 tests for the statistical method or 5 tests for the simplified method. For critical applications, 100% testing may be specified. ATA determines the appropriate test quantity based on the specific project requirements, anchor type, substrate conditions, and consequence of failure.
Does proof load testing damage the anchor?
No. Proof load testing is a non-destructive test — the anchor is loaded to a fraction of its ultimate capacity and remains fully serviceable after testing. The proof load is specifically calculated to verify installation quality without exceeding the anchor's elastic capacity. This distinguishes proof testing from ultimate load testing, where the anchor is loaded to failure and cannot be reused.
What happens if an anchor fails a proof load test?
A proof load test failure indicates that the anchor could not sustain the required proof load, which means it may not achieve its design capacity in service. ATA documents the failure — load at failure, failure mode, and any displacement data — and reports this to the specifying engineer. The failed anchor is typically removed and replaced, and additional testing of adjacent anchors may be required to assess whether the failure is isolated or systematic. The failure mode (bond failure, cone failure, steel failure) provides diagnostic information about the cause.
Get a quote for Proof Load Testing
Every engagement begins with a direct conversation with an RPEQ-qualified structural engineer. Contact ATA to discuss your project and receive a detailed scope and quote.
Other Services
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Destructive Testing to Determine Actual Anchor Capacity in Specific Substrates
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Precision Measurement of Anchor Movement Under Load
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Engineering Guidance on Anchor Selection, Test Specification & Failure Criteria
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