An object of the present invention is to provide a durometer enabling a contact portion in contact with an object to perform smooth piston motion. The durometer includes a main body unit including a movable unit pressed continuously against an object to be measured, a first sensor outputting acceleration information corresponding to an acceleration of movement of a contact part of the object to be measured in contact with the movable unit in a pressing direction, a second sensor outputting reactive force information corresponding to a reactive force at the contact part of the object to be measured in contact with the movable unit, a motor, a crank mechanism driven by the motor and causing the main body unit and the movable unit to perform piston motion, and at least one buffering member disposed on a periphery of the main body unit.

An object of the present invention is to provide a durometer enabling a contact portion in contact with an object to perform smooth piston motion. The durometer includes a main body unit including a movable unit pressed continuously against an object to be measured, a first sensor outputting acceleration information corresponding to an acceleration of movement of a contact part of the object to be measured in contact with the movable unit in a pressing direction, a second sensor outputting reactive force information corresponding to a reactive force at the contact part of the object to be measured in contact with the movable unit, a motor, a crank mechanism driven by the motor and causing the main body unit and the movable unit to perform piston motion, and at least one buffering member disposed on a periphery of the main body unit.

A methods and systems for determining a change in condition of a rock bolt. Some methods may comprise, at a first point in time, propagating shear and longitudinal ultrasonic waves along the rock bolt to measure a first time of flight for each of the shear and longitudinal waves, at a second point in time after the first point in time, propagating shear and longitudinal ultrasonic waves along the rock bolt to measure a second time of flight for each of the shear and longitudinal waves, and using the relative changes of the first and second time of flights, determining the change in condition of the rock bolt section.

A methods and systems for determining a change in condition of a rock bolt. Some methods may comprise, at a first point in time, propagating shear and longitudinal ultrasonic waves along the rock bolt to measure a first time of flight for each of the shear and longitudinal waves, at a second point in time after the first point in time, propagating shear and longitudinal ultrasonic waves along the rock bolt to measure a second time of flight for each of the shear and longitudinal waves, and using the relative changes of the first and second time of flights, determining the change in condition of the rock bolt section.

An actuator control system, mechanical testing system, and method for adaptive control of an actuator of a mechanical testing device is provided. The method includes applying a mechanical load to the specimen with the actuator, resulting in receiving a load sensor signal from a load sensor and a displacement sensor signal from a displacement sensor, deriving lumped dynamics of the mechanical testing device by analyzing a phase and magnitude relationship between a current command of a motor of the mechanical testing device and a resultant deflection of the specimen, and controlling the actuator based on the derived lumped dynamics of the mechanical testing device such that the controlling results in a stable motion.

An actuator control system, mechanical testing system, and method for adaptive control of an actuator of a mechanical testing device is provided. The method includes applying a mechanical load to the specimen with the actuator, resulting in receiving a load sensor signal from a load sensor and a displacement sensor signal from a displacement sensor, deriving lumped dynamics of the mechanical testing device by analyzing a phase and magnitude relationship between a current command of a motor of the mechanical testing device and a resultant deflection of the specimen, and controlling the actuator based on the derived lumped dynamics of the mechanical testing device such that the controlling results in a stable motion.

Disclosed is a pressure-bearing device for simulating an excavation unloading test of a high-energy-storage rock mass. The pressure-bearing device comprises pressure-bearing blocks, a casing pipe and sealing rings, wherein the two pressure-bearing blocks are respectively arranged at two ends of a to-be-tested rock mass; the casing pipe can be arranged outside the to-be-tested rock mass and the pressure-bearing blocks in a sleeving mode and is attached to the to-be-tested rock mass and the pressure-bearing blocks; and the sealing rings are arranged outside the pressure-bearing blocks and the casing pipe in a sleeving mode, so that the sealing rings can be tightly pressed on the casing pipe and the pressure-bearing blocks through fastening elements. Further disclosed is a sealing method for simulating an excavation unloading test of a high-energy-storage rock mass.

Disclosed is a pressure-bearing device for simulating an excavation unloading test of a high-energy-storage rock mass. The pressure-bearing device comprises pressure-bearing blocks, a casing pipe and sealing rings, wherein the two pressure-bearing blocks are respectively arranged at two ends of a to-be-tested rock mass; the casing pipe can be arranged outside the to-be-tested rock mass and the pressure-bearing blocks in a sleeving mode and is attached to the to-be-tested rock mass and the pressure-bearing blocks; and the sealing rings are arranged outside the pressure-bearing blocks and the casing pipe in a sleeving mode, so that the sealing rings can be tightly pressed on the casing pipe and the pressure-bearing blocks through fastening elements. Further disclosed is a sealing method for simulating an excavation unloading test of a high-energy-storage rock mass.

A system for measuring loading on a test specimen. The system includes the test specimen arranged between a first loading bar and a second loading bar. The system further includes a first loading unit and a second loading unit configured to apply a first load and a second load to the first and second loading bars, respectively. The system further includes a first clamp and a second clamp configured to hold the first and second loading bars against the first and second loads, respectively. The system further includes a clamp actuating unit configured to selectively release at least the first clamp. The clamp actuating unit further includes a controller configured to electrically actuate at least one first electromechanical transducer from a retained state to a released state to release the first clamp, such that the first loading bar applies a first loading wave to the test specimen.

A system for measuring loading on a test specimen. The system includes the test specimen arranged between a first loading bar and a second loading bar. The system further includes a first loading unit and a second loading unit configured to apply a first load and a second load to the first and second loading bars, respectively. The system further includes a first clamp and a second clamp configured to hold the first and second loading bars against the first and second loads, respectively. The system further includes a clamp actuating unit configured to selectively release at least the first clamp. The clamp actuating unit further includes a controller configured to electrically actuate at least one first electromechanical transducer from a retained state to a released state to release the first clamp, such that the first loading bar applies a first loading wave to the test specimen.