A load frame for applying a tensile load to a test sample during a test or measurement includes a first gripper for gripping a first end of the test sample, a second gripper for gripping a second end of the test sample, and a tensioner for applying the tensile load to the test sample. The load frame further includes a first end tube that encircles the first gripper, a second end tube that encircles the second gripper, and a center tube that encircles a mid-portion of the test sample during the test or measurement. A system such as a wave-generating system may be used to measure the test sample through the center tube during a test or measurement.