Construction Materials Testing – Asphalt
We perform a variety of asphalt laboratory tests to help evaluate mixture properties and document material characteristics for paving projects. Our services include testing asphalt content, aggregate gradation, drilled core density, and maximum theoretical density. We also provide asphalt plant and field services.
Laboratory Testing
Asphalt Content and Aggregate Gradation
The asphalt content test measures the percentage of asphalt binder in the mixture and provides the aggregate gradation. Binder is removed through ignition or approved solvent extraction, and the remaining aggregate is analyzed through sieve testing. These tests help document mixture components and compare gradation to project specifications.
Density of Drilled Cores (Bulk Specific Gravity)
Density testing on drilled cores helps assess the in‑place condition of the asphalt pavement. A bulk specific gravity test measures the weight of a hot‑mix asphalt (HMA) core under three conditions:
- dry
- saturated‑surface‑dry (SSD), where water fills the air voids
- submerged in water
Using these measurements, we calculate values such as bulk specific gravity, apparent specific gravity, bulk SSD specific gravity, and absorption.
Maximum Theoretical Density (Gmm) and Percent Compaction
The theoretical maximum specific gravity (Gmm) represents the specific gravity of an HMA mixture with all air voids removed. This value is determined in the laboratory and is used as a reference point for evaluating pavement compaction. Percent compaction is calculated by comparing drilled‑core density to the maximum theoretical density.
Asphalt Plant Services
We provide independent Quality Assurance (QA) testing and observation during asphalt production to support agency and project‑specific acceptance requirements. Services include:
- sampling of Hot Mix Asphalt (HMA) from haul units
- gradation and asphalt content testing
- bulk specific gravity testing
- theoretical maximum density
- volumetric analysis and air void determination
- verification of job mix formula (JMF) compliance
- observation of plant operations, stockpiles, and production controls
- documentation of daily production quantities and test results
Our team works collaboratively with plant QC staff while maintaining the independence required for QA and acceptance testing. Our experience includes municipal, DOT, and airport paving projects across multiple asphalt producers and mix designs.
Asphalt Field Services
Our asphalt field services support paving operations through on‑site observation, sampling, and testing during placement. Common activities include:
- observing paving operations and placement procedures
- measuring loose mat temperature and thickness
- sampling in‑place asphalt for density and acceptance testing
- coordinating with plant testing results
- documenting quantities placed and daily paving activities
Coordinating field and plant services provides clients with a clear, comprehensive understanding of asphalt quality from production through installation. Integrated services support communication between plant and paving operations, promote consistency in reporting, and reduce administrative effort for owners and engineers.
Frequently Asked Questions
Asphalt testing and inspection should be planned early in the project to align with specifications and construction schedules. Early coordination helps support efficient testing and reduces the chance of disrupting paving operations.
Compaction is a key factor in pavement performance. Insufficient compaction can allow air and water into the pavement, accelerating aging and deterioration. Density testing helps verify that compaction levels meet project requirements.
Asphalt cores provide laboratory‑measured density and are typically used for acceptance testing. Density gauges offer fast, non‑destructive readings that support quality control during construction. Gauge results must be correlated to core results to determine true density values.