A test apparatus for measuring strength of a specimen includes: a lower container having an opening that opens upward; an upper container having an opening that opens downward and being sized to be insertable into the opening of the lower container; a support unit that is provided in the opening of the lower container and supports the specimen; a pressing unit including an indenter that presses the specimen, and a load measurement unit that measures a load applied to the indenter; and a movement mechanism that moves the indenter closer and away relative to the support unit, in which when the specimen supported by the support unit is pressed by the indenter moved by the movement mechanism, the upper container is positioned so as to cover the specimen.

A method including obtaining a metal pipe with a longitudinal submerged arc weld, an axis of the longitudinal submerged arc weld being oriented parallel to a rotationally symmetric axis of the metal pipe and cutting a first test beam and a second test beam from the metal pipe with each test beam extending on both sides of the axis of the longitudinal submerged arc weld and has a cuboid shape. The method further including forming a double-beam assembly by clamping two spacers between the first and second test beams such that the two spacers are symmetrically disposed at an equal distance on either side the longitudinal submerged arc weld. The method further including immersing the double-beam assembly in a liquid test solution for a predetermined period of time before removing it from the liquid test solution and disassembling the double-beam. The method further including examining the first and the second test beam using a metallographic sectioning method.

A loading frame for fiber reinforced polymer (FRP)-concrete bond tests includes a standing guide tower, a base section, and a loading beam. The standing guide tower is perpendicularly mounted to the base section. A testing load is applied to the loading beam when performing a series of FRP-concrete bond tests. A sliding end of the loading beam is positioned into a channel within the standing guide tower allowing the loading beam to be positioned at a preferred height. The engagement between the loading beam and the standing guide tower reduces secondary forces. The loading frame is mobile and may also be used with existing testing devices and systems used to perform the series of FRP-concrete bond tests.

A test apparatus used for simulating debonding between a carbon fiber reinforced polymer (CFRP) and concrete in a CFRP-strengthened structure consists of a primary structural block, a secondary structural block, an adjustable hanger, a receiving slot, an attachment mechanism, a pull-off disk, a connecting plate having a plurality of rods. The adjustable hanger and the secondary structural block are slidably positioned into the receiving slot that traverses into a structural body of the primary structural block. The adjustable hanger is mainly used during double-shearing tests and mixed-mode tests, wherein both shearing and peeling is analyzed in mixed-mode tests. The secondary structural block is used in double-shear tests, mixed-mode tests, single-shear tests, tension pull-off tests, and beam-bend tests. The attachment mechanism, which holds the primary structural block, the secondary structural block, and the adjustable hanger together, is also used during single-shear tests and beam-bend tests.

A method including obtaining a metal pipe with a longitudinal submerged arc weld, an axis of the longitudinal submerged arc weld being oriented parallel to a rotationally symmetric axis of the metal pipe and cutting a first test beam and a second test beam from the metal pipe with each test beam extending on both sides of the axis of the longitudinal submerged arc weld and has a cuboid shape. The method further including forming a double-beam assembly by clamping two spacers between the first and second test beams such that the two spacers are symmetrically disposed at an equal distance on either side the longitudinal submerged arc weld. The method further including immersing the double-beam assembly in a liquid test solution for a predetermined period of time before removing it from the liquid test solution and disassembling the double-beam. The method further including examining the first and the second test beam using a metallographic sectioning method.

The invention relates to a force measuring arrangement (3) in particular for applying a test parameter to a specimen and/or for measuring a resistance force applied by the specimen, having at least one force absorption element (25), a first fastening device and a force transmission element (27), wherein the force absorption element (25) can be fastened to a force measuring device in a movable manner by means of the first fastening device, wherein the force absorption element (25) is designed to measure a relative force acting between two force absorption regions, namely a first force absorption region and a second force absorption region (51), wherein the first fastening device is able to be connected to the force absorption element (25) in a force-transmitting manner via the first force absorption region, wherein the second force absorption region (51) is able to be connected to the force transmission element (27) in a force-transmitting manner by means of a second fastening device, wherein the force transmission element (27) is designed to apply a test parameter to a specimen. The force measuring arrangement is notable in that the second fastening device has a magnet (37) that is designed to retain the force transmission element (27) at least in a state connected to the second force absorption region (51) in a force-transmitting manner.

A system for monitoring rock damage in deep engineering environment includes an acoustic emission sensor assembly and an acoustic emission amplifier assembly. The assemblies are mounted on a rock mechanics test system. The acoustic emission sensor clamp includes a coupling screw, as well as a clamp cover, a clamp cylinder, and a coupling panel threadedly connected in sequence. The acoustic emission amplifier assembly includes an acoustic emission amplifier, an upright column having a guide rail, a lifting support plate, and a support plate lifting oil cylinder. Additionally, an evaluation method based on acoustic emission tempo-spatial evolution laws is presented. According to the properties of acoustic emission, fractal characteristics of damage evolution processes of rock test pieces are analyzed and the relationship between stress, energy and fractal dimension in the whole process of tensile deformation damage of the rock test pieces is obtained.

Described herein are examples of improved material (and/or universal) testing machines having a lower crossbeam that may be moved via a drive system of the material testing machine. In some examples, this may be accomplished via drive shafts with different threading in upper and lower portions, and/or independent drive systems for upper and lower crossbeams. The ability to dynamically adjust (e.g., raise) the lower crossbeam may allow an operator to interact with test samples at a more comfortable height, and reduce the need for an operator to repeatedly bend and/or kneel.

An example material testing apparatus (100) includes: guide means (110); sample test means (120) for holding a sample (130) and applying a test force to the sample (130); a crosshead (150) arranged to support at least a portion the sample test means (120), wherein the crosshead (150) is moveable about the guide means (110); crosshead drive means (180) for moving the crosshead (150) generally vertically about the guide means (110), wherein the crosshead drive means (180) is driven by an electric machine (302) in a driving configuration; and a controller (170) arranged to: configure the electric machine (302) into the driving configuration; control the crosshead drive means (180) to move the crosshead (150) generally vertically about the guide means (110); and configure the electric machine (302) into a braking configuration, wherein in the braking configuration a winding of the electric machine (302) is connected together with a low resistance connection.

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.