When it comes to roads, pavements, and platforms, not all soil is created equal. Understanding how much load your subgrade can support is critical for safety, compliance, and long-term performance. That’s why CBR Testing — or California Bearing Ratio Testing — is one of the most valuable tools in construction.
At Ideal Geotech, we provide fast, standards-compliant CBR testing services across NSW, QLD, and the ACT. Our tests deliver precise soil strength data for pavement design, council approval, and engineering certification.
1.What Is a CBR Test?
CBR (California Bearing Ratio) testing is a geotechnical test that measures the load-bearing capacity of soil or subgrade materials. It simulates the impact of vehicle loads on the ground and provides a percentage value that indicates soil strength. The higher the CBR value, the stronger the soil.
This data is essential for:
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Designing road bases and subgrades
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Determining pavement layer thicknesses
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Planning earthworks platforms for buildings and industrial sites
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Engineering driveways, access roads, and heavy-duty pavements
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Meeting council or RMS specifications for subdivision and infrastructure works
2. When Do You Need a CBR Test?
You’ll typically require CBR testing when your project includes:
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Roads, driveways, or pavement construction
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Vehicle traffic over natural or compacted fill
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Gravel bases for warehouses or industrial buildings
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Structural slabs supported on engineered fill
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Construction Certification (CC) or subdivision approvals
Many local councils and Transport for NSW (RMS) guidelines mandate minimum CBR values (e.g., 15%, 25%) depending on surface usage — making accurate testing a compliance necessity.
3. How We Perform CBR Testing
At Ideal Geotech, we offer both laboratory-based and in-situ field CBR testing, depending on your project requirements.
🧪 Lab-Based CBR Testing
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Samples are collected from site or submitted to our NATA-aligned lab
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Soils are compacted into moulds following AS1289 standards
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A plunger simulates loading while penetration resistance is measured
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CBR % value is calculated from load-penetration curves
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Soaked testing is available to replicate worst-case water conditions
🚧 In-Situ CBR Testing (On-Site)
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Performed directly on compacted fill or prepared subgrades
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Provides real-time results for construction QA or as-built certification
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Ideal for fast-paced projects where quick verification is essential
4. What’s Included in a CBR Testing Report?
Every CBR test report from Ideal Geotech is engineered for clarity, compliance, and immediate usability:
✅ CBR % values for each depth or layer tested
✅ Soil classification, moisture content, and density readings
✅ Optional: Soaked vs. unsoaked CBR comparisons
✅ Clear interpretation for use in design and council submission
✅ Reports delivered per sample or bundled within full geotechnical packages
Our reports are structured for easy review by engineers, certifiers, and council planners.
5. Why Choose Ideal Geotech for CBR Testing?
✔️ AS1289-compliant procedures trusted by engineers and regulators
✔️ Flexible service options – lab-based or on-site testing
✔️ Fast turnaround with clear, no-jargon reporting
✔️ Transparent, per-test pricing or package options
✔️ Coverage across NSW, ACT, and QLD
From road upgrades to subdivision approvals, we help you take control with dependable data, every time.
6. Book Your CBR Test Today
Need accurate CBR testing for your construction project?
Whether you’re building a driveway, road, or earthworks platform, Ideal Geotech delivers fast, professional service backed by engineering expertise.
Order Our Geotechnical Services Now
