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 test system includes subsystems for application to a test sample of a range of conditions that might be encountered in an actual application. Conditions may include the presence of particular fluid environments, temperatures, pressures, and mechanical loads including tensile and bending loads. The system is particularly suited for elongated samples such as tubular products used in oil and gas applications, though a range of samples may be tested.

A double-cross composite fabric membrane biaxial tensile strength test piece is provided, including a core region and four cantilevers. The four cantilevers extend outwards around the core region and form a cross shape. Each cantilever is connected to the core region via an edge transition region. An end portion of the cantilever is a clamping section. The clamping section is provided with a clamping end rubber rod. The clamping end rubber rod is used for connecting to a clamp of a biaxial tensile testing machine. The clamping section is three-layered. The cantilever and the edge transition region are double-layered. The core region is single-layered. The edge transition region is in the shape of a quadrangle rounded at four corners. A manufacturing method of the test piece is also provided.

A stand-alone miniature in-situ multiaxial universal testing equipment, is disclosed herein. The device comprises a multi-axial loading fixture unit, a data processing unit, an image capturing unit, a data acquisition unit, motor unit, loading jaw, loading heads, displacement sensor, lighting unit and telecentric lens. The device is a stand-alone, in-plane, in-situ miniaturized multiaxial loading fixture that is capable of loading a wide variety of samples including but not limited to, metallic, ceramics and composites.. The loading fixture is capable of in-plane tension, in-plane compression in one-direction or two directions both independently and simultaneously and as well 4-point bending loading of the samples.

A universal materials testing machine is disclosed. In one embodiment, the machine comprises a plurality of grips holding a circular material specimen sheet; the grips being capable of pulling the material specimen radially outward. Each grip is connected to a force measurement sensor such as a load cell. The grip and the load cell assembly is connected to a linear actuator assembly. The linear actuator assembly comprises a motor connected to an arm that can move along a straight line. The actuator pulls or pushes the load cell and grip assembly. A camera module captures images of the specimen while being stretched or released. A data processing system gathers camera module images along with force measurements from the load cells. An analysis module running on the data processing unit computes stress and strain measurements and fits them to user selectable material model.

A method for determining material parameters includes applying a character grid over a planar sample, clamping the planar sample in a frame in accordance with directions of orthotropy of the planar sample; collecting a first set of data that describes a first position of the character grid; applying predetermined normal and shear stresses to the planar sample thereby bringing the planar sample into a deformed state and changing the position of the character grid; collecting a second set of data that describes a second position of the character grid, determining a relative position change of the character grid by correlating the collected first set of data and the second set of data; determining a relative displacement and a current distortion state of the planar sample; determining a deformation equilibrium of the deformed state of the planar sample; and calculating the material parameters from the deformation equilibrium.

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 p-y curve-based element test device is provided. An upper support plate is located above a lower support plate and is fixedly connected to the lower support plate through truss supports symmetrically arranged on left and right sides, and at least one truss support is arranged on each side. A sample container, a servo consolidation mechanism and multidirectional servo actuators are connected to the truss support on the two sides. The servo consolidation mechanism is located above the sample container, and the multidirectional servo actuators are arranged above the servo consolidation mechanism and below the sample container, respectively. Identical loads are synchronously applied from above and below to realize horizontal movement of a pile element to simulate the load condition of a soil body, and a pressure is applied by a servo consolidation device to simulate the stress condition of the soil body at a certain depth.

Aspects of the technology relate to an apparatus and method for testing a material for use in a lighter-than-air craft deployable in the stratosphere. The apparatus and method may include and use a base plate and at least one ring component to attach to the base plate to secure a portion of the material. The at least one ring component has an elliptical shape including a minor radius having a first predetermined length and a major radius having a second predetermined length. The base plate receives a gas to inflate and pressurize the portion of the material. The first predetermined length and second predetermined length are selected to impart a stress ratio up to a predetermined maximum ratio onto the portion of the material through a predetermined temperature range when the portion of the material is inflated to a predetermined pressure.

A p-y curve-based element test device is provided. An upper support plate is located above a lower support plate and is fixedly connected to the lower support plate through truss supports symmetrically arranged on left and right sides, and at least one truss support is arranged on each side. A sample container, a servo consolidation mechanism and multidirectional servo actuators are connected to the truss support on the two sides. The servo consolidation mechanism is located above the sample container, and the multidirectional servo actuators are arranged above the servo consolidation mechanism and below the sample container, respectively. Identical loads are synchronously applied from above and below to realize horizontal movement of a pile element to simulate the load condition of a soil body, and a pressure is applied by a servo consolidation device to simulate the stress condition of the soil body at a certain depth.