A portable flexure fixture including a fixture housing, a translatable plug, a load ring, and a support ring. The fixture housing includes a first end opposite a second end, a plug receiving opening extending into the first end and a test opening extending into the second end. The support ring is disposed in the fixture housing. The translatable plug is insertable into the plug receiving opening of the fixture housing and is translatable in both a sample engaging direction and a sample releasing direction. Further, the load ring is coupled to the translatable plug and is positioned at a sample facing end of the translatable plug such that translation of the translatable plug in the sample engaging direction translates the load ring in the sample engaging direction and translation of the translatable plug in the sample releasing direction translates the load ring in the sample releasing direction.

Disclosed is a deepwater platform welded joint testing system. The testing system comprises a host unit, a hydraulic unit and a control unit, wherein the control unit is connected with the host unit and the hydraulic unit respectively; the host unit comprises a bearing frame placed on a bearing base, biaxial tension/compression loading oil cylinders mounted on the bearing frame, a lateral force resistant mechanism connected to the front ends of the biaxial tension/compression loading oil cylinders, counter-force supports fixed to the top end of the bearing frame and biaxial bending loading oil cylinders mounted on the counter-force supports. According to the deepwater platform welded joint testing system, through the independent or synergistic effect of the six loading oil cylinders, stretching and fatigue performance tests of a large complex structure under uniaxial tension/compression, uniaxial bending, biaxial tension/compression, biaxial bending and uniaxial/biaxial tension/compression and bending composite loads can be achieved.

Coal rock three-dimensional strain field visual system and method are provided under a complex geological structure. The system includes a stress condition simulation system and a strain monitoring system. The stress condition simulation system includes a similar simulation experiment rack, a loading system and a circular slideway. The method includes preparing a 3D printing wire, printing a strain visual similar model, simulating a stratum dip angle and a gas-containing condition, applying stress fields, recording a cracking and dyeing condition of microcapsules inside the model, and the like. The system can realize tracing the generation and development of internal cracks in simulation models with complex geological conditions, and tracing the three-dimensional movement of internal ink dots to draw four-dimensional images of displacement fields.

A device and method for testing the bearing capacity of grouped pillars in the inclined goaf under coupled biaxial static and disturbance stresses are provided. Four protection rings are arranged on a base, each protection ring is installed with one machine frame therein, a bottom end of the machine frame is connected with the base and a top end thereof is connected with a transverse frame. Sliding rails are arranged on two sides of the base, side frames are installed on the sliding rails. A vertical force loading device is arranged at a bottom of a workbench, transverse force loading devices are arranged on inner sides of the side frames respectively. A force disturbance device is arranged at the bottom of the transverse frame. An upper slidable clamping seat and an upper pressure disk are arranged above the samples, and a lower slidable clamping seat is arranged below the samples.

A device and method for testing bearing capacity of single-row grouped pillars in a horizontal goaf under biaxial loading is disclosed. Four fixed rings are arranged on testing machine base, and have stands installed therein respectively, bottom ends of the stands are connected with the base, top ends are connected with transverse frame, sliding rails are arranged on two sides of the base; the vertical force loading devices are arranged at a lower part of transverse frame and the horizontal force loading devices are arranged at inner sides of side frame. Simultaneous loading on multiple coal samples, rock samples, filling body samples, concrete samples, coal-filling samples and/or rock-filling samples can be achieved, the overall bearing capacity of a single-row group pillar system in the horizontal goaf under the biaxial compression condition can be obtained, and the mutual influence relation between grouped pillar individuals in the horizontal goaf can be attained.

A device and method for testing the bearing capacity of grouped pillars in the inclined goaf under coupled biaxial static and disturbance stresses are provided. Four protection rings are arranged on a base, each protection ring is installed with one machine frame therein, a bottom end of the machine frame is connected with the base and a top end thereof is connected with a transverse frame. Sliding rails are arranged on two sides of the base, side frames are installed on the sliding rails. A vertical force loading device is arranged at a bottom of a workbench, transverse force loading devices are arranged on inner sides of the side frames respectively. A force disturbance device is arranged at the bottom of the transverse frame. An upper slidable clamping seat and an upper pressure disk are arranged above the samples, and a lower slidable clamping seat is arranged below the samples.

Provided is a device for evaluating 360-degree bidirectional folding durability of a flexible material in which during a folding test of a film-type flexible material, a single folding device can implement both the infolding and outfolding of the flexible material relative to the unfolded state of the flexible material. To this end, the device includes: a fixing unit configured to fix a first side of the flexible material to be evaluated; a moving unit configured to fix a second side of the flexible material and disposed to be spaced apart from the fixing unit; a motion guide unit to which the fixing unit is fixed; and a motion unit connecting the motion guide unit with the moving unit.

The present disclosure discloses a reciprocating rock fracture friction-seepage characteristic test device and method. The test device includes an X-axis shear system, a Y-axis stress loading system, a Z-axis stress loading system, a servo oil source system, 5 a pore pressure loading system, and a host. The X-axis shear system includes an X-axis EDC controller, an upper shear box, a lower shear box, an X-axis left hydraulic cylinder, an X-axis right hydraulic cylinder, an X-axis left pressure head, an X-axis right pressure head, an X-axis left pressure sensor, an X-axis right pressure sensor, an X-axis displacement sensor, and an X-axis 10 displacement sensor. The pore pressure loading system includes an air cylinder, a pressure gauge, a pressure reducing valve, a fluid inlet pipeline, a fluid outlet pipeline, and a flowmeter.

A multiaxial fatigue machine comprising a rotational mechanism; a driven shaft arranged collinearly with a first power shaft of the rotational mechanism and a reciprocating mechanism. The rotational mechanism has a first motor and a first fastening element configured to be connected to a test element that can be also connected to a second fastening element of the driven shaft to transmit to said test element a rotational force produced by the first motor. The reciprocating mechanism has a second power shaft, a second motor, and a linear rotational transmission, wherein the reciprocating mechanism is configured to apply an alternating force on the test element.

A biaxial load test specimen includes a main body and four arms. The main body has a plurality of through-holes aligned along axial directions of two load axes orthogonal to each other. The four arms extend from the main body in the respective axial directions of the load axes. Each of the arms has a plurality of slit grooves extending, on respective extensions of the through-holes aligned in the axial directions, along the respective axial directions.