40-Foot Beam System
A uniquely configured MTI-100K system for testing 40-foot long I-Joist composite wood beams is operating at the J M Huber facility in Maysville, GA.. The load frame required several radical modifications to accomplish the planned beam tests.
A 40-foot long by 26-inch high steel I-Beam had to pass through the lower portion of the load frame and be rigidly attached to the lower reaction surface of the frame at the center of the beam span! The drive motor was rotated 90 degrees and passes out the rear cover of the frame. The chain drive coupling the two loading ball screws was relocated from the frame base up to the top of the machine. Finally, the frame height was extended an additional 16 inches to accommodate beams up to 24 inches in depth.
A smaller 20-foot steel I-Beam hangs below the moving crosshead by means of a pivot attachment. The pivot allows the upper beam to 'float' to provide equally distributed force at the two loading points. Two 'Floating' load support points can be easily positioned anywhere along the base beam to permit testing of beams of any length up to the full 40 feet. Two similar floating loading points are suspended from the upper loading beam. (The loading point are all large radius, pivoting loading heads and also include the longitudinal degree of freedom required by ASTM D-198 test method for lumber in structural sizes.)
Multiple sets of adjustable lateral supports can be positioned anywhere along the beam, and can be easily configured for any required width.
Finally a special deflection sensor array (6 sensors) is mounted below the beam to accurately measure the deflection of the center of the beam with respect to the supports.
The control and measurement system calculates all parameters specified in ASTM D-109 and D-5055.
Similar extended length beam testing systems can be configured for you based upon any of the standard MTI floor-model load frames. A 60-foot beam length is the maximum supported. Shorter span length systems are readily available.
