Automatic Concrete Compression Testing Machines

Gilson Automatic Concrete Compression Machines perform complete strength tests for concrete cylinders, beams, cubes, cores, and other sample types, with minimal operator input. Operator interaction is only necessary for sample preparation and positioning, and for removal of samples after test completion. A single selection on the touchscreen controller initiates the automated test cycle.


250,000lbf Automatic Concrete Compression Machines
Models: AC-250, AC-250F, AC-250M, AC-250MF, AC-250MR, AC-250MRF
325,000lbf Automatic Concrete Compression Machines
Models: AC-325, AC-325F, AC-325M, AC-325MF, AC-325MR, AC-325MRF
450,000lbf Automatic Concrete Compression Machines
Models: AC-450, AC-450F, AC-450M, AC-450MF, AC-450MR, AC-450MRF

The Automatic controllers are programmed to follow the specification requirements of the selected test for specimen contact, pre-loading, rate of load, break detection, data acquisition, and return of the piston to the home position. Variations in load rates and applications are eliminated, ensuring accurate, repeatable, and documented results that strictly conform to ASTM and AASHTO test methods. Automated testing and documentation of results also lead to higher rates of productivity with fewer errors.

Automatic Compression Machine Comparison

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Sample type, test method, entry of specimen data, and test parameters are selected on the Windows-based touchscreen controller. Force, stress, and rate of load are displayed continuously, with options for graphing. The quiet and energy-efficient automated drive system regulates load rate and applied force by feedback during sample loading.

USB and LAN ports, along with Wi-Fi capability, allow easy data collection via flash drive or transfer to the user’s PC or network for reporting of results. Test data can be printed individually or transferred in summary form. Testing laboratory, sample ID, and client information are entered and stored for improved accuracy in reporting and distribution.

The integrated electric motor and hydraulic pump system operate at variable speeds depending on loading demands to achieve and maintain required pressures. This energy-efficient configuration reduces heat build-up, extends the surface life of the hydraulic components, and is noticeably quieter. Rugged welded steel frames exceed ACI 363 requirements for system rigidity, and top-mounted pistons avoid wear from accumulated test debris.

Safety features include a large emergency stop button, a hydraulic relief valve to prevent loading beyond machine capacity, and a limit switch that stops the piston from advancing beyond its limit. Hinged fragment guard doors are made from clear Lexan® to permit the operator to view the sample during testing while still ensuring safety.

All Automatic Compression Machine units are supplied ready for compression strength testing of 6x12in (152x305mm) concrete cylinders with user-supplied unbonded neoprene capping pads and steel retainers. A full suite of Compression Machine Accessories is available for tests of flexural beams, cubes, tensile splitting, and other configurations of cylinders and cores.

In addition to these methods, models that perform ASTM C469 Modulus of Elasticity (MOE) and Poisson’s Ratio on 4 or 6in (101 or 152mm) cylinders feature either one or two LVDT inputs and other factory modifications. Compressometer and Compressometer/ Extensometer testing fixtures for MOE and Poisson’s ratio testing must be purchased separately.

Automatic Concrete Compression Machines are available with power supply options of 110V, 60Hz or 230V, 50Hz electrical systems.