Novel markers that can be attached physically to a tensile specimen with a center guide to allow for measuring correct strain, as well as a binder that fixes and holds a pin guide to its location on the specimen during the test.

A tension load fixture for applying tension or loading forces to a specimen comprises a pair of tension arms and an imaging device. The pair of tension arms are configured to releasably couple to opposite end regions of a specimen and to apply tension or loading forces to the specimen. The specimen is configured to be positioned between the pair of tension arms and defines a notch between the opposite end regions of the specimen. The notch extends from a side of the specimen to a middle region of the specimen. The imaging device is configured to capture one or more images of the middle region of the specimen and is configured to rotate about a central axis of the tension load fixture that is proximate to the middle region of the specimen to facilitate generation of a three-dimensional image of the middle region of the specimen as the specimen is subjected to tension or loading forces.

A racquet including a frame including a head portion, a handle portion, and a throat portion. The head portion is a tubular structure including inner and outer peripheral walls, each having inner and outer surfaces. The head portion of the racquet being formed of a fiber composite material. The fiber composite material includes a plurality of ply arrangements. Each includes a pair of plies defining first and second angles with respect to a composite axis. A section of the outer peripheral wall from the inner surface to the outer surface includes at least three ply arrangements overlaying each other, and the first and second angles of at least two of the at least three ply arrangements being at least 35 degrees. When the racquet is tested under a racquet torsional stability test, the racquet has an angular deflection of less than 5.5 degrees about a longitudinal axis.

An apparatus for testing paving samples includes a base that includes a paving sample tray about the cabinet and configured for translation relative to the cabinet. A roller is configured for imparting compressive forces to a sample carried by the sample tray. An arm is configured for moving the roller from a stowed position to an in-use position where the roller contacts the sample. A cylinder assembly having a piston therein supplies pressure forces to the arm to move the arm from the stowed position to the in-use position, wherein a depth of travel of the arm is limited by the sample. As the sample is compressed, the depth of travel increases. A measurement device is in communication with the cylinder for determining an amount of travel of the arm to thus determine an amount of compression of the sample.

A racquet including a frame including a head portion, a handle portion, and a throat portion. The head portion forms a hoop that defines a string bed plane. The head portion of the racquet being formed of a fiber composite material. When the racquet is tested under a racquet forward/rearward bending test, the racquet has a forward/rearward deflection with respect to the longitudinal axis of at least 8.5 mm when measured in a direction that is perpendicular to the string bed plane and perpendicular to the longitudinal axis. When the racquet is tested under a racquet torsional stability test, the racquet has an angular deflection of less than 5.5 degrees about a longitudinal axis.

A racquet extending along a longitudinal axis and including a frame including a head portion, a handle portion, and a throat portion. The head portion forms a hoop that defines a string bed plane. At least the head portion and the throat portion of the frame are formed at least in part of a fiber composite material. When the racquet is tested under the racquet lateral bending test, the racquet has a lateral deflection of at least 6.0 mm when measured in a direction that is parallel to the string bed plane and perpendicular to the longitudinal axis.

A device and a method for testing tensile resistance of multiple-row grouped pillars in an inclined goaf are provided. The bottoms of stands of the device are connected with a testing machine base, and the tops of the stands of the device are connected with a transverse frame; an upper slideable clamping seat and a lower slideable clamping seat are semi-cylindrical blocks, multiple lower loading jaws that are positioned to have a same central line are arranged on the lower slideable clamping seat, each of the lower loading jaws is opposite to a corresponding one of the upper loading jaws, the lower loading jaws are welded to the lower slideable clamping sea to test the tensile resistance of samples together; the upper part of the upper slideable clamping seat is connected with an upper pressure disk, and the lower slideable clamping seat is connected with a lower pressure disk.

The disclosure provides a variable dip fault slip simulation test method, which relates to the technical field of indoor simulation test of underground engineering. The variable dip fault slip simulation test method of the disclosure adopts a sample device and a loading device, which includes the following steps: Step 1. sample preparation; Step 2. sample assembly; Step 3. loading preparation; Step 4. sample loading. The variable dip fault slip simulation test method of the disclosure can prepare rock like samples with different dip interfaces, simulate the slip failure process of faults with different dip angles, as well as the normal dip slip and reverse dip slip of faults, facilitate the operation of slip simulation test, and collect test data automatically and accurately.

A Bauschinger effect test fixture that cooperates with a test machine for stretching and compressing materials to perform a Bauschinger effect test on a test piece having a symmetrical configuration with two wide ends and a narrow middle part. The fixture includes two identical split bodies, where each split body has a base provided, longitudinally from a central part to one end of the base, with a limiting groove corresponding to a half of the profile of the test piece. Two sides of the groove are arranged symmetrically with a plurality of threaded through holes and a cover is provided along its central axis with two threaded through holes with which the test piece is pressed tightly by bolts. An end of the cover corresponding to a notch of the limiting groove is provided with a through groove configured for placing a stress ultrasonic detection probe on the test piece.

A device is provided for determining material properties of a material, preferably a wood or a wooden material, having a pin arrangement having at least two pins, a drive unit for at least partially driving the pins into the material using a defined force, and a measuring unit for measuring both the penetration depth of at least one of the at least two pins and also an electrical resistance between two of the pins.