The present invention relates to a stress-strain testing system for a large-diameter steel pipe pile of an offshore wind turbine and a construction method, comprising a steel pipe pile, wherein copper belt type sensor cables are correspondingly welded on both sides of the steel pipe pile along an axis direction; each sensor cable is sequentially covered with an epoxy adhesive, gold foil paper and an angle steel welded on the steel pipe pile centering on the copper belt type sensor cable; a fiber core of each copper belt type sensor cable is transferred into a high-strength armored optical cable by a special fixture and then is led out; and the high-strength armored optical cable is connected with a Brillouin optical fiber demodulator. The present invention is applicable to the field of foundation engineering testing and detection technology.

Methods of detecting pipeline weakening are described herein. The methods include creating a pressure wave in a fluid flowing in a pipeline using an input transducer located at a first position along the pipeline; measuring the pressure wave using an output transducer positioned at a second position along the pipeline that is spaced from the first position, and generating an output signal based on the pressure wave; analyzing the output signal to determine a stiffness of a sidewall of the pipeline positioned between the input transducer and output transducer; and determining if the sidewall includes a defect based on the stiffness of the sidewall, including analyzing a frequency response of the output signal to detect the defect.

A method is provided. An actual fatigue curve limit is determined for actual stress of a drilling component based on an actual yield strength of a material of the drilling component. A plurality of drilling parameters is simulated for the drilling component to determine one or more estimated stresses enacted on the drilling component for one or more combinations of the plurality of drilling parameters. A component life cycle of the drilling component is determined based on the actual fatigue curve limit and the plurality of drilling parameters. A consumed component life of the drilling component is determined for an actual drilling step utilizing the drilling component, and a remaining life of the drilling component after the actual drilling step is determined.

There is a viscoelastic strain sensor that includes a sensing layer including a viscoelastic material, the viscoelastic material including a viscoelastic hydrogel and a conductive nanofiller. The viscoelastic material has a fractional resistance change that increases with an increase of an applied tensile strain, and the viscoelastic material has a fractional resistance change that decreases with an applied compressional strain.

A system for determining parameters of porous media or material, which in an embodiment is biological tissue, includes an actuator and a displacement monitor. The actuator is adapted to apply a displacement to tissue at a particular frequency selected from a range of frequencies, and the force monitor adapted to monitor a mechanical response of tissue. The system also has a processor coupled to drive the actuator and to read the mechanical response, the processor coupled to execute from memory a poroelastic model of mechanical properties of the material, and a convergence procedure for determining parameters for the poroelastic model such that the model predicts mechanical response of the tissue to within limits.

A method for testing an arresting unit (15) for locking a foldable wing tip portion (11) to a wing (5) that includes a fixed wing (9), a foldable wing tip portion (11), and a folded position, an actuation unit (13) for actuating movement of the foldable wing tip portion (11), and an arresting unit (15) for locking the foldable wing tip portion (11). The method includes: locking the foldable wing tip portion (11) in the extended position by the arresting unit (15), controlling the actuation unit (13) to move the foldable wing tip portion (11) in the direction towards the folded position, such that the foldable wing tip portion (11) urges against the arresting unit (15) with a predefined test load, detecting deformation of the arresting unit (15) during or after application of the test load, and comparing the detected deformation to a predefined threshold deformation.

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.

A testing device for simultaneously testing two rotor blades and/or two rotor blade segments for a wind power installation, to a method for simultaneously testing two rotor blades and/or two rotor blade segments for a wind power installation, to a method for testing a rotor blade and/or a rotor blade segment for a wind power installation, and to the use of a testing device for testing a rotor blade and/or a rotor blade segment for a wind power installation and/or for simultaneously testing two rotor blades and/or two rotor blade segments for a wind power installation. The testing device comprises a first adapter element for fastening thereto a first rotor blade or rotor blade segment, a second adapter element for fastening thereto a second rotor blade or rotor blade segment, a support structure to which the first and the second adapter element are fastened so as to be rotatable about a common rotation axis, an excitation device which is configured to apply a static and/or cyclic load to the first and/or the second rotor blade or rotor blade segment, wherein the first and the second adapter element are connected to each other.

Disclosed is a material testing system that includes a fixture, a frame, a load sensor, a displacement sensor and a computer system coupled to the material testing system. The computer system includes one or more processors, one or more memory devices coupled to the one or more processors, one or more computer readable storage devices coupled to the one or more processors, wherein the one or more storage devices contain program code executable by the one or more processors via the one or more memory devices to implement a method for detecting a change in a material testing sequence. A computer program product that implements a method for detecting a change in a material test sequence, and methods for detecting a change in a material test sequence or fatigue test is further disclosed.

There is a viscoelastic strain sensor that includes a sensing layer including a viscoelastic material, the viscoelastic material including a viscoelastic hydrogel and a conductive nanofiller. The viscoelastic material has a fractional resistance change that increases with an increase of an applied tensile strain, and the viscoelastic material has a fractional resistance change that decreases with an applied compressional strain.