Check out our Concrete Laboratory capabilities and equipment!

Equipment and Testing

Mixing:

The Concrete Laboratory has the capability to mix pastes with a high-shear mixer, a vacuum mixer, or a small planetary mixer. Mortars are prepared with three different sizes of planetary mixers. Concrete is prepared with a 2 ft3 pan mixer, a 0.75 ft3 or 6 ft3 drum mixer, and a high-shear mixer.

Curing:

Curing and conditioning is performed using temperature-controlled curing tanks, a walk-in environmental chamber, and three smaller environmental chambers. A separate room maintains a specific temperature and relative humidity condition during testing.

Fresh Properties:

Fresh property testing includes air content testing (using the volumetric method, pressure method, and super air meter), unit weight, and setting (using the automatic setting time apparatus and penetration testers). Automatic setting time and penetrometer equipment can identify set times on most materials.

Workability:

Workability is assessed with a slump cone, the box test, a flow table, and a dynamic shear rheometer.

Volume Instability:
 

Plastic, chemical, drying, and autogenous shrinkage can all be measured using testing apparatuses in the Concrete Laboratory. Volume change is a leading cause of concrete cracking, and incorporates many design, materials, and environmental variables. The Concrete Laboratory has one of few dual ring tests in the United States, allowing us to correlate measured temperature-induced strain to stress which indicates cracking potential of a material. We can also measure coefficients of thermal expansion.

Mechanical Testing:

Within the concrete laboratory, we have hydraulic testing equipment that can load up to one million lbs, 500,000 lbs, and 325,000 lbs for determining compressive strength, split tensile strength, elastic modulus, and Poisson’s ratio. In addition, we perform flexural strength and bond pull-off testing.

Durability Testing:
 

Depending on the needs of a project, durability testing may incorporate any combination of surface resistivity, bulk resistivity, water absorption, freeze-thaw, chloride migration, chloride ponding and titration, and corrosion potentials. The Concrete Laboratory can also express pore solution from fresh and hardened concrete specimens to understand ionic concentrations within the system.

Microstructural Characterization:

The Concrete Laboratory can monitor hydration reactions over time using an isothermal calorimeter or a semi-adiabatic calorimeter, perform titration to understand ionic concentrations, cycle relative humidity exposure to measure concrete response using the dynamic vapor sorption analyzer, identify the presence of calcium oxychloride using the low temperature differential scanning calorimeter, and determine oxide contents using x-ray fluorescence.

Physical Characterization:

The Concrete Laboratory can perform physical characterizations such as Blaine fineness testing, density, specific surface area, and aggregate gradations.