Isothermal calorimetry is a technique to accurately measure the heat released by hydration reactions between water and cement. It is also used to study the effect of different admixtures on the cement hydration rate. Performing the isothermal calorimetry test at different temperatures makes it possible to calculate the cement activation energy. The TAM Air calorimeter consists of eight channels and functions in a temperature range of 20 C to 40 C.
This 20-kip capacity hydraulic actuator is mounted on a testing frame and powered by a 60 GPM Sauer-Sundstrand pump. The actuator is controlled by a MTS Test Star IIm 7-axis controller. The load frame can be used to test small-scale specimen, such as in the accelerated dowel damage test shown on the right. In this test, a concrete beam is generated with a dowel spanning a simulated joint. The are testing in fatigue loading to evaluate dowel performance over high numbers of vehicle loads.
The ALF is a large testing frame postioned over a concrete foundation slab. Mounted on theload frame are four (4) 100 kip hydraulic actuators, which are powered by a 60 GPM Sauer-Sundstrand pump and controlled by a MTS Test Star IIm 7-axis controller. This allows for independent operation of eahc actuator or opertation of multiple actuators simultaneously. The ALF is designed to perform testing on full-scale pavement joints under cyclic vehicle loading. Tension and compression tests can be performed with these actuators.
The Instron 600DX is the lab’s primary compression and tension machine for small concrete, stone, steel, and even wooden samples. Hydraulic-powered with loading force up to 135,000 lbs (600 kN), the Instron features both compression and tension loading bays and is compatible with several different loading heads for ASTM C39, C78, C469, C496, D7012, and several other tests. The Instron is controlled via Partner software to provide precise control over loading, customizable test parameters, and detailed readouts and graphs depicting loading, stress, strain, and failure over time.
The Testmark, a CM-4000 series, is the secondary compression testing machine for concrete samples, typically used in ASTM C39, C78, and C496 tests. It features a valve-controlled hydraulic pump capable of supplying over 100,000 lbs of compressive force, steel fragment guard doors front and back, and a digital load-indicating unit to provide the results.
Combined with different types of sensors, dataloggers and multiplexers are used to measure the response of a concrete sample under different mechanical and thermal loads. Deformation, length change, and temperature change are between the parameters that are measured to calculate some of the concrete's engineering properties such as stiffness and coefficient of thermal expansion.
The fatigue load frame is equipped with a 5.5-kip actuator, powered by a 2.6 GPM hydraulic pump, and controlled by the MTS FlexTest 40 controller. The frame is currently configured to fatigue concrete beams in third-point bending. The test set-up pictured is used to investigate the effects of overloads on the fatigue performance of concrete beams.