A cyclic dynamic loading-confining pressure instantaneous unloading test device includes a load-supporting frame system, a cyclic dynamic loading system, a confining pressure loading system, a monitoring system, a control system and a data analysis system; the top of the load-supporting frame system is equipped with the cyclic dynamic loading system, the cyclic dynamic loading system is connected with the control system, the bottom of the load-supporting frame system is equipped with the confining pressure loading system, the cyclic dynamic loading system and the confining pressure loading system are equipped with the monitoring system, the monitoring system and the control system are connected with the data analysis system.

The invention discloses a method and a system for predicting the corrosion fatigue life of prestressed concrete bridges. A corrosion level of the strand is predicted to obtain the residual tension force of a structure. A stress concentration factor is integrated to consider the stress concentration effect caused by pitting corrosion, and a growth model of the elastic stress of the strand under the coupled effect of corrosion and fatigue is proposed. A growth model of the plastic stress of the strand is established using a cross-section loss of the strand as a fatigue damage parameter based on a degenerated elastic modulus of the concrete after fatigue. Failure criteria for the concrete, the strand, and a longitudinal tension bar are defined, so that a set of methods for analyzing the life of a prestressed concrete bridge subjected to corrosive environment and fatigue load are formed.

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 true triaxial testing system for disturbance experiment with broadband and low amplitude of a high pressure hard rock includes a low-frequency disturbance true triaxial mechanism, a variable-frequency low-speed disturbance rod mechanism and a rapid single-side unloading type specimen box. The low-frequency disturbance true triaxial mechanism and the variable-frequency low-speed disturbance rod mechanism are distributed along a straight line. The low-frequency disturbance true triaxial mechanism is independently used or cooperates with the variable-frequency low-speed disturbance rod mechanism for use. The rapid single-side unloading type specimen box cooperates with the low-frequency disturbance true triaxial mechanism for use.

A triaxial rock mechanics test system for high-strain-rate cyclic dynamic loading is provided, including: a host loading module, a dynamic cyclic loading module, and a dynamic measurement module. The host loading module includes a loading frame, a triaxial pressure mechanism and an actuator that are provided inside the loading frame. The dynamic cyclic loading module includes a driving mechanism, a fixed mechanism and a mobile mechanism. The dynamic measurement module is configured to acquire axial pressure data, radial deformation data and axial deformation data of the rock sample during a test. In the triaxial rock mechanics test system for high-strain-rate cyclic dynamic loading of the present invention, an energetic rod is driven by an electrical explosion of a metal wire to generate a strong shock wave with controllable peak pressure, duration and waveform.

An atomic-force-microscope-based apparatus and method including hardware and software, configured to collect, in a dynamic fashion, and analyze data representing mechanical properties of soft materials on a nanoscale, to map viscoelastic properties of a soft-material sample. The use of the apparatus as an addition to the existing atomic-force microscope device.

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.

The present invention relates to a corrosion-fatigue-coupled test method and device for a steel bridge deck. The method includes: 1) installing an orthotropic steel bridge deck (OSBD) and pasting filter paper; 2) installing a sodium chloride solution delivery pipe; 3) installing an infrared (IR) lamp; 4) preparing a corrosive solution; 5) coupling corrosion and fatigue; and 6) acquiring test data. A device constructed by using the method includes a to-be-tested OSBD, a support device, a pressure pump, a water tank, a monitoring device, an IR lamp, a plastic water pipe, a thermostat and a rotary sprayer. The present invention solves the problem of laboratory accelerated corrosion of the OSBD. The present invention fully considers a coupling effect of a corrosive medium and an alternating stress, so that the created simulation environment is close to a service environment of the OSBD, and the test data are effective and reliable.

The present invention relates to an experimental apparatus for researching characteristics of subsea tunnel at bottom of seabed under wave, comprising main control system, wave making test system, rock and soil confining pressure test system and water level regulation test system, wherein a bottom of the rock and soil confining pressure test system is connected with the water level regulation test system; a bottom of the wave making test system is connected with the rock and soil confining pressure test system; and all test systems are electrically connected with the main control system. The experimental apparatus, when being small, may simulate the situation of the subsea tunnel under a nonlinear complex wave, may consider the common action of the seabed and the wave, and may regulate water levels and soil pressures, having perfect functions and effectively exploring the effect of various aspects on the subsea tunnel.

Provided is an apparatus for fatigue testing a bulge tool having a WH-type skeleton, the apparatus including: a fixing bracket having tool holes penetrated through opposite sides thereof; a tool housing coupled to the tool hole of the fixing bracket and having the bulge tool inserted and installed therein; a moving rail installed at one side of the fixing bracket in a lengthwise direction of the tool housing and providing a reciprocating movement path facing the tool housing; a moving bracket reciprocating along the moving rail; a pusher protrudingly installed from the moving bracket toward the tool housing and moving in and out of the bulge tool; a measurement means installed between the pusher and the moving bracket, measuring a load applied to the bulge tool; and a drive means for generating power reciprocating the moving bracket on the moving rail.