Page 6 - CEGE Spring 2024

MAST CONT...
Ben Worsfold (Ph.D., University of California Berkeley) heard of the MAST Lab while at Berkeley, where he had worked with a one-dimensional setup for testing structures. In addition to the size, force, and degrees of freedom in the system, Worsfold is especially impressed with the ease of constraining out-of- plane motion, which is a challenge in a one-dimensional testing facility.
Paired with the MAST Lab at UMN is the Theodore V. Galambos Structural Laboratory, located in the Civil
Engineering Building. That lab is
well suited for large-scale testing of long span structures, such as bridge girders and other structures that do
not require the MAST Lab capabilities. The Galambos Lab features a universal testing machine capable of applying 600,000 pounds in compression. A new data acquisition system (DAQ), hydraulic control system, and upgrades to actuators have been ordered to increase that lab’s capabilities and efficiency and allowing for hybrid
simulation testing. Worsfold will soon be setting up the first experiment on the new equipment to test ultra-high performance concrete girders.
Future
Director Linderman is positive about the future for these labs. She notes that large-scale experiments are still needed because computer modeling, while advancing rapidly, cannot replace the need for testing.
She draws an example from her interest in Formula One Racing. “Every few years they change the specifications, and the cars need to be redeveloped. That industry has the finest designers, finest engineers, and the finest testing equipment. Yet on the first run, you still see parts flying off the newly designed cars. To me, that shows that modeling has not yet been perfected and speaks to the continuing need for large-scale, physical experiments.”
The MAST Lab is a valuable resource with extensive opportunities for real- world, large-scale structural experiments to test new materials, validate models, and test components for remediation
or retrofit in existing structures. And the MAST researchers are dreaming big!
You can support work of the MAST Lab by giving directly at https://z.umn.edu/ GivetoMASTLab or contact Contact Shannon Wolkerstorfer (External Relations) at swolkers@umn.edu for more information.
Huntington Bank Stadium, was built
to test large structural components or models. It has strong walls and a strong floor to accommodate the forces and weight required for such large-scale testing. Three main areas make up the testing space: staging, testing, and control.
The Staging Area allows large samples to be built, assembled, or delivered.
Once the sample is ready, it is moved into the Testing Area. Mounted at the top of the MAST Lab’s testing area is a steel crosshead that can precisely twist, compress, or stretch large samples with six degrees of freedom. Researchers can simulate many forms of stress to test building components or materials.
UMN’s MAST Lab is able to handle specimens 18 to 35 feet high and 20x20 feet in-plane; longer test specimens can
be placed at a diagonal. One of the
key features of the equipment is the hydraulic bearings, the largest of their kind designed by MTS. The bearings make it possible to apply large axial loads to test specimens while exhibiting minimal friction in the bearings when
imposing loading in the horizontal directions. Without this feature, it would be nearly impossible to know the amount of horizontal force going into the test structure versus the force necessary to overcome friction in the bearings.
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The laboratory, located east of
CONTROL ROOM
The testing mechanism is run from a control room with windows facing
the testing floor. The equipment is driven by specialized software devel- oped by MTS with collaboration from Professor Emeritus Carol Shield, who served as the Director of the labo- ratory through more than the first decade of its operation. In addition, the facility has impressive data collection capabilities and a large data repository from its days as a NEES facility.