A bond test apparatus includes a test tool, a stage for mounting a bond for testing, and a drive mechanism comprising a voice coil. The voice coil is coupled to either the stage or to the test tool and is configured to provide relative movement between the stage and the test tool such that the bond applies a test force to the test tool. The bond test apparatus can also include a velocity sensor configured to sense an instantaneous relative velocity between the stage and the test tool, and a controller configured to control the drive mechanism in response to a signal from the velocity sensor. The bond test apparatus can also include a retarding mechanism coupled to the stage or the test tool and configured to apply, in response to relative movement between the stage and the test tool, a retarding force opposing the driving force.

An example material testing machine includes: a first crosshead; a first drive shaft configured to move the first crosshead when actuated; a housing comprising an air inlet and an air outlet; a drive motor within the housing and configured to actuate the first drive shaft; a motor drive circuit configured to provide electrical power to the drive motor; and a motor drive cooling system configured to cool the motor drive circuit, the motor drive cooling system comprising: a cooling fan configured to generate an airflow from the air inlet of the housing to the air outlet of the housing, wherein a total surface area of the air outlet is greater than a total surface area of the air inlet such that an air pressure of the airflow decreases from the air inlet towards the air outlet; a duct configured to direct a path of the airflow between the air inlet and the air outlet; and a heat sink thermally coupled to the motor drive circuit and positioned within the airflow in the duct.

A sensor apparatus for footwear includes at least one pair of light sources and at least one pair of light receivers, each light receiver being positioned and configured to receive light emitted from a respective one of the light sources. A pair of movable curtains functions to adjust the amount of light received by the pair of light receivers. The curtains are movable conjointly such that the amount of light received by one of the light receivers is inversely proportional to the amount of light received by the other light receiver. (FIG. 1B).

The present invention concerns a device and method for selectively or simultaneously measuring shear strength and pore water pressure of a soil in the field. The device includes a rod adapted to be at least partially inserted into the soil and rotated. The rod has a soil engaging portion and an opposed coupling portion configured to be coupled to a torque applying machine or device. The device further includes at least one vane blade extending at least partially along and from the soil engaging portion of the rod for shearing the soil when rotated together with the rod. At plurality of pore water pressure sensors are operatively associated with at least one of the soil engaging portion and the at least one vane blade. The sensors are configured to sense pressure indicative of the pore water pressure of the soil while the at least one vane blade shears the soil.

A device is for detecting compaction and shear strength characteristics of an asphalt mixture during construction compaction. The device includes a fixed frame and a detection system. The detection system includes a display, a control panel, a test claw, an electric motor, a lift switch, a torque sensor and a temperature sensor. The control panel includes a power switch for controlling the electric motor and a speed regulator for controlling a rotation speed of the test claw. An output end of the electric motor is connected to an input end of the torque sensor, and an output end of the torque sensor is connected to an input end of the test claw. An output end of the test claw is provided with a claw-shaped blade. The claw-shaped blade is provided therein with the temperature sensor.

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 device for testing overall anchorage performance of a basalt fiber reinforced plastic (BFRP) anchor cable includes an anchor cable anchoring system and a data acquisition system. The anchor cable anchoring system includes a test bed, BFRP arranged over the test bed, and a distributed optical fiber bonded to a surface of the BFRP, the test bed being provided with an anchoring section at one end and an outer anchoring section at the other end, the anchoring section anchors one end of the BFRP, and the outer anchoring section anchors the other end of the BFRP. The data acquisition system includes a modem and a grating connected to two ends of the distributed optical fiber in series, and a center hole jack and a dynamometer arranged between the outer anchoring section and an end of the test bed, and the BFRP penetrates the center hole jack and the dynamometer.

To prevent a crack from occurring on a sheared end face due to press forming, a technology is provided for evaluating and predicting a crack limit of the sheared end face of a metal sheet and determining press forming conditions. In a deformation limit evaluation method for, when deforming by press forming a metal sheet subjected to shearing, evaluating a deformation limit of the sheared end face of the metal sheet, the deformation limit is evaluated by an index value obtained from two stress gradients at an evaluation position among stress distributions occurring in the vicinity of the sheared end face of the metal sheet due to the press forming, which gradients are a stress gradient in a sheet thickness direction and a stress gradient in a direction away from the sheared end face.

Disclosed is a testing device for measuring interfacial shear properties between fibers and media, including a main body, which is a rectangular plate-like structure with L-shaped plates provided at the bottom ends of the main body, a connecting rod provided at a top right of the main body, a groove provided at the top of the main body; and four rotating grooves are provided inside the groove. The rotating grooves are cylindrical structures with raised centers at both ends; and a mounting piece is installed above the left end of the main body; a magnet of a displacement micrometer is connected to a tension trolley, a high-definition camera is turned on, weights are added into a loading bucket and the fiber movement is observed until the fiber is pulled out or sliding friction occurs, and then the camera is stopped and accurate data is tested.

Characterizing the decay of the microstructure of a drilling fluid gel using a model based on two exponential functions. Based on the model, identify at least two components of the decay model comprising a fast decay component and a slow decay component, wherein the fast decay component decays more quickly than the slow decay component. The decay of the microstructure of the gel over a time period can be determined using a rheometer or viscometer. Wellbore processes, including start up and tripping operations can be optimized based on the determination of the fast decay component and/or a slow decay component of the drilling fluid gel.