A test method for characterizing the mechanical properties including the surface adhesion energy γ on the basis of the experimentally derived P-A relationship, where P means the indentation load under the penetration depth h of an indenter pressed onto a test specimen with surface adhesion, and A means the contact area of indentation at the contact radius a under the applied load of P. This test method enables the implementation for quantitatively as well as simultaneously characterizing the adhesion energy as well as the various mechanical properties (elastic/elastoplastic/viscoelastic properties) of soft materials.

A footprint generator capable of applying a constant force includes: a base plate in which a target surface may be on an upper surface of the base plate; a shoe mounting member that is apart from the upper surface of the base plate and capable of mounting a shoe; a driving unit that is apart from the upper surface of the base plate and capable of moving the shoe mounting member up and down; and a force measuring unit configured to measure an impact force when the shoe mounting member descends and contacts the shoe with the target surface to generate a footprint on the target surface.

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.

An instrument and method for mechanical properties in situ testing of materials under a high temperature and complex mechanical loads are provided. The instrument includes: a support frame module used to provide a stable support and an effective vibration isolation for each functional module of the instrument; a high-frequency fatigue load applying module used to apply a high-frequency fatigue load on a tested sample; a static-dynamic mechanical load applying module used to apply a combination of static-dynamic tension/compression/bending loads on the tested sample; a high/low temperature applying module used to apply a variable temperature environment from a low temperature to a high temperature on the tested sample; and an in-situ monitoring module that may integrate a surface deformation damage measurement assembly, a three-dimensional strain measurement assembly, a microstructure measurement assembly, and an internal damage detection assembly according to a practical testing requirement.

An instrument and method for mechanical properties in situ testing of materials under a high temperature and complex mechanical loads are provided. The instrument includes: a support frame module used to provide a stable support and an effective vibration isolation for each functional module of the instrument; a high-frequency fatigue load applying module used to apply a high-frequency fatigue load on a tested sample; a static-dynamic mechanical load applying module used to apply a combination of static-dynamic tension/compression/bending loads on the tested sample; a high/low temperature applying module used to apply a variable temperature environment from a low temperature to a high temperature on the tested sample; and an in-situ monitoring module that may integrate a surface deformation damage measurement assembly, a three-dimensional strain measurement assembly, a microstructure measurement assembly, and an internal damage detection assembly according to a practical testing requirement.

A marine climate environment-bending load collaborative acceleration test method is provided, including conducting a static bending load loading test in an outdoor marine climate environment, conducting an alternate cycle of a dynamic bending load loading test in the outdoor marine climate environment and a test in the outdoor marine climate environment, and conducting an alternate cycle of the dynamic bending load loading test and the static bending load loading test in the outdoor marine climate environment. In the present disclosure, an acceleration rate of the marine climate environment-bending load collaborative acceleration test reaches over 8 times that of the test in the outdoor marine climate environment by taking the maximum bending force as an evaluation index, which may achieve a change from a static test to a static and dynamic combined test for examining and evaluating the environmental adaptability of the metal material.

The invention discloses an experimental system of surrounding rock and lining structure under unequal surrounding pressure and water pressure, comprising: reaction wall, lining structure, external water pressure loading mechanism, internal water pressure loading mechanism, prestress-loading mechanism, surrounding rock layer and monitoring device. The Experimental System can simulate the stress characteristics and related deformation characteristics of the surrounding rock of the tunnel and the lining structure of the water conveyance tunnel under complex internal and external loads in the actual environment, and can help to analyze and study the broken appearance of the lining structure and the crack distribution after cracking.

A method of determining a minimum wall thickness for a pipe joint for use in a subsea pipeline comprises the steps of: i) determining an internal diameter of the pipe joint; ii) determining a minimum allowable hydrostatic pressure at the depth at which the pipe joint is to be used; iii) determining a target wall thickness for the pipe joint, the target wall thickness corresponding to the internal diameter and the minimum allowable hydrostatic pressure; iv) manufacturing a plurality of preliminary pipe joints having the internal diameter and the target wall thickness; v) carrying out external pressure collapse tests resulting in data representative of the hydrostatic collapse pressures at which the plurality of preliminary pipe joints collapse; vi) determining a probability distribution corresponding to the data based on a statistical tail model derived from Extreme Value Theory; vii) determining from the probability distribution a hydrostatic collapse pressure occurring with a probability of 10.sup.−5 or lower; and, viii) determining a wall thickness of the pipe joint corresponding to the internal diameter and the hydrostatic collapse pressure.

Provided is a tensile testing machine that includes a testing machine main body having a hydraulic actuator, the tensile testing machine including an estimation unit that estimates a response characteristic of the tensile testing machine, in which the estimation unit obtains the response characteristic of the testing machine main body in a state in which a first set value used for a tensile test performed by the tensile testing machine is set as a control parameter specifying operation of the hydraulic actuator, and estimates, based on the obtained response characteristic of the testing machine main body, the response characteristic of the tensile testing machine in a state in which a second set value different from the first set value is set as the control parameter.

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.