We have two laboratories qualified to provide ASR testing
Alkali-Silica Reactivity (ASR) testing requires a qualified laboratory capable of performing the test according to established standards. We have performed over 1,500 ASR tests during the 25 years that we have offered this service and have consistently received accreditation.
Our Gray, Maine and Somersworth, New Hampshire locations are qualified to perform Alkali-Silica Reactivity testing for projects located in most states, including MassDOT submittal samples. These laboratories are approved for ASTM C1260, ASTM C1567 and AASHTO T303 testing for the 2025 cement concrete producer submission cycle. These tests are also included in the laboratory’s AASHTO accreditation scope.
What is ASR testing and why is it important for your project?
Alkali Silica Reaction (ASR) is a chemical reaction that occurs within concrete, which can lead to structural damage. When alkalis in the cement react with certain aggregates, it forms a gel-like substance around the aggregate particles. As this gel expands, it causes cracking and, in some cases, premature failure of the concrete.
For ASR to take place, three key factors must be present:
- Alkalis in the cement
- Silica in the aggregate
- Sufficient moisture
ASR can drastically shorten the lifespan of concrete structures. It can affect a wide range of structures, including exterior slabs, pavements, bridges, tanks, dams, and retaining walls—particularly those exposed to water, saltwater, or de-icing chemicals.
Fine and coarse aggregate can be tested for the potential of ASR. The testing process can take either 16 or 30 days to complete once the sample is cast, depending on the specification and agency requirements. This time frame doesn’t include preparation or reporting time. We perform ASR tests using established methods, such as ASTM C1260, ASTM C1567, and AASHTO T303.
How is the testing done?
- Prepared samples are molded into rectangular bars or prisms.
- Stainless steel gauge studs are installed in the molds and remain embedded in the samples.
- Samples are cured and an initial length reading is taken in a length comparator.
- Samples are placed in a heated solution of sodium hydroxide.
- Length readings are taken periodically to detect the expansion of the samples.
Interested in learning more?
Our team members are responsive to your needs and can help coordinate a testing timeline that best fits your schedule without compromising the quality of the test results. Having two laboratories qualified to provide this service gives us the capacity to take in more samples. To find out more call our Gray office at (207) 657.2866, our Somersworth office at (603) 692.0088, or use our online contact us form.
