Concrete Testing Laboratory

Lab Location: 122 Colton Hall
Lab PIs: Stephen George and Nasser Channaoui

High Performance Concrete Laboratory

With funding from the National Science Foundation, the High Performance Concrete Laboratory in the Civil and Environmental Engineering Department is the only academic facility capable of testing very high strength concretes under uniaxial as well as triaxial states of stress. The primary testing system at this facility is capable of applying up to one million pounds of axial load on specimens under computer controlled closed-loop environment. The system can be programmed to perform triaxial tests with confining pressures of up to 20,000 psi. Concrete specimens can be tested in special environmental chambers under simultaneous cyclic load, and thermal stress conditions. The system can be programmed to apply thermal cycles with amplitudes varying between -50oC to +200oC.

The facility is also equipped with two other closed-loop testing systems for testing of large size beams, and normal strength concretes. The materials processing component of the facility includes two computer controlled micro-sizers, and fractionators for particle size analysis and categorization of industrial by-product additives to concrete, i.e. fly-ash, microsilica, and blast furnace slags. There are two new curing rooms for developing controlled conditions and studying the effects of various combinations of thermal and moisture conditions during early stages of strength development in high performance concretes.

MTS Materials Testing Systems

As part of its teaching and research effort CEE operates several MTS load frame systems. Loads ranges between 50 and 1.2 million pounds are available. The million pound machine can crack an unreinforced concrete beam in such a way as to propagate the crack completely through the beam without splitting the beam; a tap with your fingers will finish it off. This control comes from an ability to choose control methods suitable for the needs of one’s test. These machines are used in undergraduate Strength of Materials labs as well as labs on the properties of concrete. They are used for graduate research, one machine having been instrumental in half a dozen PhDs and at least as many Masters Degrees. 

The million pound machine has helped one PhD to graduate and has four others in the pipeline. Finally, research projects ranging from “Fast-Track” concrete (2500 psi in 5 hr.) to studies of why dental implants loosen and the fatigue strength of roof bolts would have been impossible without these flexible, very precise machines.

1200 kip Very Stiff Load Frame

The king of our testing machines weighs 16,000 pounds and is used to characterize the properties of concrete and rocks. It tremendously expands our testing capabilities not only through its strength but also through a collection of load cells and unique extensometers. It can also be fitted with a 12,000 psi triaxial cell or a temperature control chamber to further extend its capabilities. Directed by a TestStar digital controller, the test procedure is limited only by the imagination.

Auxiliary units: 12000-psi triaxial chamber, Temperature Controlled Chamber
Load Ranges (range max.): 1000 kip, 600 kip in triaxial vessel, 200 kip, and 55 kip.
Extensometers (range max.): Dual Averaging, 0.15-in Circumferential, In-vessel Dual Averaging, in-vessel 0.3-in circumferential

100 kip Adjustable Load Frame

The most versatile of our testing fleet, this machine has been the mainstay of our materials testing program for many years. Accepting specimens up to 7-ft. tall and equipped with auxiliary extensometers and load cells, this machine is able again and again to solve our testing problems. This machine is central to our research in high strength concrete, fiber concrete, fly ash concrete, Fast Track concrete, non-symmetric columns, and a host of others studies. This machine is one of only a few in the country that routinely tests the direct tensile strength of concrete and concrete composites.

Load Ranges (range max.): 55 kip, 5 kip
Clip Gages (range max.): 0.02 in
Extensometers (range max.): 1.0 in, 0.2 in, 0.1 in.
Other Accessories: Computer Data Acquisition, years of odd fixturing​

Mixing and Aggregate Testing

• Temperature/Humidity Controlled Curing Rooms
• 1/4-cu.yd. Mixer
• Two 6-cu.ft. Drum Mixers
• 1-qt, 10-qt. Mortar Mixers
• Concrete Aggregates Testing Facilities
• 24-cu.ft. Blue M Oven
• 6-cu.ft. Temperature Controlled Water Bath

Testing Area

• Load Floor: 8 ft x 7 ft, 1 1/2-6 sockets on 2-ft centers, 50 kip pullout, 7 1/2- ft overhead clearance
• 2-ton Manual Overhead Crane
• Sulfur Capping Fume Hood

Research Projects

• Direct Tension Testing of Concrete
• High Strength Concrete
• Fly Ash Concrete
• Fiber Concrete
• Fracture Mechanics of Concrete
• Fast-Track Concrete
• Triaxial Behavior of High Strength Concrete
• Post-failure Behavior of Concrete
• Fatigue Testing of Concrete
• Polymer Concrete, Behavior of Eccentrically Loaded non-Symmetric Columns
• Rehabilitation of Concrete Beams using Carbon Fiber Reinforced Plastic
• Behavior of Plastic Structures
• Plastic Reinforcement of Damage Unreinforced Masonry Structures