Disclosed is a three-parameter strength reduction method for slope stability evaluation. The present disclosure reflects the difference in the attenuation and contribution of the cohesion, internal friction angle and tensile strength in the process of slope instability by reducing the three parameters by different reduction factors. Based on the sudden change of the characteristic point displacement of the slope as a criterion of slope instability, the present disclosure derives the fitting relationship between the characteristic point displacement and the cohesion reduction factor. The present disclosure assumes that the comprehensive safety factor satisfies a linear relationship with the cohesion reduction factor, the internal friction angle reduction factor and the tensile strength reduction factor and derives the relationship between the comprehensive safety factor and the cohesion reduction factor. Finally, the present disclosure summarizes and proposes a three-parameter strength reduction method and provides the steps for analyzing the slope stability through this method.

A miniature temperature-controlled triaxial tester for testing unsaturated soil suitable for micro-computer tomography (CT) scanning and a method thereby. The triaxial tester includes a device body, where the bottom of the device body is fixed on a base, and the top of the device body is provided with a strain control device. The device body includes a vertically arranged polymethyl methacrylate shell, a PMMA inner cover is nested inside the PMMA shell, and a vacuum gap is formed between the PMMA shell and the PMMA inner cover; a pressure cell is formed by a space defined by the PMMA inner cover, a sample accommodating area for accommodating a test sample is arranged in the pressure cell, a heating element is arranged below the sample accommodating area and connected to a temperature control device, and a temperature sensor is arranged inside the PMMA inner cover and connected to a receiver.

A method is described for continuously evaluating mechanical and micro structural properties of a rolled metallic material (L) in a cold deformation process, subjected to combinations of deformation forces selected among compression forces, traction forces and bending moment applied at low deformation speed in a range comprised between 1*10.sup.−4 and 10*10.sup.−4 s.sup.−1 which corresponds to laboratory static conditions and at high deformation speed in a range comprised between 0.1 and 10 s.sup.−1 which corresponds to dynamic pp conditions, the method comprising the step of: —measuring characteristic parameters of the cold deformation process under dynamic conditions, comprising at least one value of temperature (T), deformation (ε) and deformation speed ({acute over (ε)}) of the rolled sheet (L); characterized in that it further comprises the steps of: —calculating the traction yield strength at high deformation speed (σ.sub.YD) according to equation (I), being: σ.sub.c a compression strength of the rolled sheet (L) when a compression force (Fc) is applied thereon; σ.sub.t a traction strength of the rolled sheet (L) when traction forces (Tin, Tout) are applied thereon; σ.sub.bend a strength due to the bending of the rolled sheet (L) when a bending moment is applied thereon; and m, n, p are a first, a second and a third parameter respectively being a function of continuously-measured operating conditions of the cold deformation process and being a function of the rolled sheet (L) in terms of chemical composition and of preceding operating conditions of a hot deformation process, in terms of hot-rolling start and end temperature, winding temperature and grain size; calculating the traction yield strength at low deformation speed (σ.sub.YS) according to equation (II), being: σ.sub.YD the traction yield strength at high deformation speed; f a statistical optimization factor between data measured at low deformation speed and at high deformation speed; α a first characteristic parameter of the rolled sheet (L) being a function of a chemical composition of the rolled sheet (L) and of operating conditions of a hot deformation process of the rolled sheet (L); and β a second characteristic parameter of the rolled sheet (L) being a function of the cold deformation process calculated as (III), being {acute over (ε)} the deformation speed, Q an activation energy of the deformation of the rolled sheet (L) evaluated through laboratory tests, R the Boltzmann constant of ideal gases, and T the temperature of the rolled sheet (L).

The invention relates to a method for determining the replacement state of wear of a rope made of a textile fibre material, wherein, in the course of using the rope, the elongation of the rope is monitored over its entire length and the rope is discarded if the elongation of the rope over the entire length exceeds a predetermined maximum value (%). The method according to the invention is characterized in that also the local elongation of a discrete rope section is monitored and the rope is discarded if the local elongation of the rope section exceeds a predetermined maximum value (%), with the maximum value of the local elongation of the rope section being greater than the maximum value of the elongation of the rope over the entire length.

Provided is a deformation tester where a specimen is deformed after starting and can be observed and analyzed in any deformation state without removal. The tester includes: a detachable part repeating a relative displacement cycle of a second part to a first part, two portions of the specimen attached to a first and a second attachment portion of the first and the second part, the specimen deformed from a first to a second shape state and back to the first shape state during the cycle; and a main body part the detachable part is detachably attached to; wherein state retaining means for fixing a relative position of the second to the first part in at least one shape state is freely attachable to the detachable part mounted on the main body part and the detachable part with the state retaining means is freely attachable to the main body part.

A strain testing rig for testing an elongate specimen has at least three restraints arranged to be spaced apart along the elongate specimen. Each restraint engages the elongate specimen at a respective contact location such that the strain testing rig defines an independent strain zone between each pair of adjacent contact locations. A drive mechanism moves the at least three restraints to stretch each independent strain zone such that the length of each independent strain zone increases independent of strain in the other zones. The restraints can be pivotably connected end-to-end as a chain linkage. The drive mechanism drives the chain linkage from a first position in which a forward facing side of the chain linkage which opposes the specimen is substantially straight to a second position in which the forward facing side of the chain linkage is convexly curved.

A miniature temperature-controlled triaxial tester for testing unsaturated soil suitable for micro-computer tomography (CT) scanning and a method thereby. The triaxial tester includes a device body, where the bottom of the device body is fixed on a base, and the top of the device body is provided with a strain control device. The device body includes a vertically arranged polymethyl methacrylate shell, a PMMA inner cover is nested inside the PMMA shell, and a vacuum gap is formed between the PMMA shell and the PMMA inner cover; a pressure cell is formed by a space defined by the PMMA inner cover, a sample accommodating area for accommodating a test sample is arranged in the pressure cell, a heating element is arranged below the sample accommodating area and connected to a temperature control device, and a temperature sensor is arranged inside the PMMA inner cover and connected to a receiver.

A multiple degree of freedom sample stage or testing assembly including a multiple degree of freedom sample stage. The multiple degree of freedom sample stage includes a plurality of stages including linear, and one or more of rotation or tilt stages configured to position a sample in a plurality of orientations for access or observation by multiple instruments in a clustered volume that confines movement of the multiple degree of freedom sample stage. The multiple degree of freedom sample stage includes one or more clamping assemblies to statically hold the sample in place throughout observation and with the application of force to the sample, for instance by a mechanical testing instrument. Further, the multiple degree of freedom sample stage includes one or more cross roller bearing assemblies that substantially eliminate mechanical tolerance between elements of one or more stages in directions orthogonal to a moving axis of the respective stages.

A tribological testing simulator includes a base having a pair of catchers that clamp onto a specimen, a punch that is drawn through the specimen, and a plurality of sensors that take measurements of respective regions of the specimen. The sensors measure their respective regions of the specimen as it is drawn from an un-deformed state to a deformed state, and facilitate conducting a tensile strip friction test. In some embodiments, the catchers have flat inserts that facilitate conducting a strip stretch or draw test simultaneously with a tensile strip friction test. In other embodiments, the catchers include drawbead inserts that facilitate conducting a drawbead friction test simultaneously with a tensile strip friction test.

An impact test fixture capable of applying preload on a composite laminate, which is composed of a base, a clamping mechanism and a loading mechanism, where the clamping mechanism is positioned on an upper surface of the base and fixedly connected to the base through a bolt, and the loading mechanism is installed at an end of the base. A composite laminate is placed in a rectangular groove of the base. A first wedge block and a second wedge block are positioned in a base sliding groove between a pressing block and a baffle plate, and inclined planes of the two wedge blocks are oppositely installed; the baffle plate is matched with the base through a first fixing bolt and a second fixing bolt, a loading bolt passes through a screw hole at a side end of the base and is matched with the first wedge block.