11 results about "Strainmeter" patented technology

The application discloses a tunnel surrounding rock strength reserve monitoring device and an evaluation method, relates to the field of tunnel surrounding rock stress monitoring, and comprises a main stem, at least two three-way supports which are arranged at intervals along the axial direction of the main stem, and a data processing module; each three-way support is provided with a strain gauge corresponding to the axial direction, the radial direction and the ring direction of the tunnel; the data processing module is used for calculating the internal stress according to the external stress of the tunnel measured by the strain gauge. The application solves the problem that most of the existing monitoring technologies can only monitor the supporting structure, and can accurately evaluate the stability of the tunnel surrounding rock, and the cost is relatively low.

The invention discloses a ground stress measurement method based on rock core radial deformation and differential strain fusion, which comprises the following steps: acquiring a drill hole wall image and a rock core surface image, identifying common features according to the drill hole wall image and the rock core surface image, and mapping azimuth information of the common features of the drill hole wall image into the rock core surface image; measuring radial deformation data of the rock core, calculating a radial deformation curve, determining a principal stress direction according to wave crest and wave trough positions of the radial deformation curve, cutting the rock core according to the radial deformation data, marking end surfaces along the wave crest and wave trough directions, and respectively arranging strain gauges on the three surfaces to measure three-dimensional strain. The main strain ratio is calculated according to the three-dimensional strain, three main stress absolute values are calculated according to the radial deformation of the rock core and the main strain ratio, and the complex behavior of the rock core in the stress release process is reflected more accurately through a machine learning algorithm, so that the measurement precision in the main stress direction is remarkably improved.

This invention discloses a three-string multifunctional measuring anchor and its measurement method, belonging to the field of geotechnical engineering monitoring technology. The anchor consists of an anchor section and three-string steel wire strain gauges connected coaxially in alternating configurations. The three steel wires are distributed at 120° intervals along the circumferential cross-section. The strain gauge center column is stiffly matched to the anchor body and can be arranged according to the magnitude of the bending moment. During measurement, the three-string steel wire strain gauges are first calibrated, followed by installation, frequency acquisition, and data calculation. This allows for the simultaneous acquisition of the anchor's axial strain, maximum curvature and direction, axial force, and maximum bending moment. Based on the curvature, further integration can be performed to obtain the deflection and internal settlement curves of the soil and rock mass, determining the maximum settlement value and location. This invention features a segmented combined structure with flexible length adaptation, enabling remote automated monitoring. It combines axial force, bending moment, and internal deformation monitoring functions of the soil and rock mass, and can be used for safety monitoring of tunnels, slopes, foundation pits, and underground mining engineering.

Method for performing a strain measurement on a component (10), wherein a strain gauge (12) is attached to the surface of the component (10) and the strain measurement on the component (10) is carried out using the strain gauge (12). The component (10) consists, at least in the area of ​​the component (10) where the strain gauge (12) is attached to the surface of the component (10), of an anisotropic and / or inhomogeneous material, wherein the anisotropy and / or inhomogeneity of the material is caused, at least substantially, by the fact that the material has components (14) which are arranged in the material in such a way that they form a regular pattern of periodically repeating structures.Before attaching the strain gauge (12) to the component (10), the pattern is detected with a detection device in an area where the strain gauge (12) is to be attached to the surface of the component (10), and the exact position and / or orientation in which the strain gauge (12) is attached to the surface is selected depending on the detected pattern.

The invention discloses a stable prevention and control test device for a roadway crossed coal pillar type irregular island working face, which is characterized in that corresponding stones, soil, coal briquettes, coal cinder and the like are filled and tamped in a top plate cavity of a top plate module to form rock and soil so as to simulate the geological condition of a real roadway top plate, and a triaxial strain gauge and a top plate separation instrument are buried in the rock and soil; therefore, the stress and deformation conditions of the rock soil can be detected. During a test, the top plate module is disassembled, assembled and transferred by using the side conveying module and the lifting module, which is very labor-saving and convenient. In the test process, the lifting oil cylinder can be adopted to drive the upper support to ascend and descend so as to assist in loading and unloading the top plate module and exert initial pressure on rock soil, and then the multiple pressure exerting cylinders are utilized to exert point-shaped pressure on the pressure exerting blocks and the pressure exerting plates so as to simulate confining pressure at different positions of the roadway top plate. Meanwhile, an impact hammer of the impact module can be used for applying impact force at different positions to the upper support, and the impact force can be conducted to the pressure applying block and the pressure applying plate, so that rock burst is simulated.

The utility model relates to the field of earth crust stress strain observation, in particular to an indoor complete machine calibration device for a vertical drilling strain gauge, which comprises a mounting frame, a pressurizing assembly is arranged on one side of the mounting frame and used for changing the vertical stress of surrounding rock, and a mounting plate is fixedly connected to one side of the mounting frame and used for fixing the mounting plate. One side of the mounting plate is fixedly connected with a positioning assembly, the cylindrical surface of the positioning assembly is provided with a driving mechanism, the driving mechanism is in threaded connection with the positioning assembly, the cylindrical surface of the positioning assembly is rotatably connected with a fixing device, and the fixing device is matched with the driving mechanism. And meanwhile, indoor calibration of the whole machine is effectively performed.

The application discloses a tunnel hole wall secondary stress recovery test method and device, and relates to the technical field of tunnel construction surveying.The method is that firstly, an integrated combined strain gauge containing strain gauges in 0° direction, 45° direction, 90° direction and-45° direction and the like is pasted on the end surface of a rock core; secondly, initial strain values in each direction are measured and recorded; thirdly, the rock core is placed between upper and lower saddle-shaped cushion blocks, and the rock core is subjected to secondary stress recovery test in each direction; finally, the 0° direction and the 90° direction are divided into a group, the-45° direction and the 45° direction are divided into another group, the stress values recovered by two perpendicular directions in each group are regarded as confining pressures, and the final secondary stress measurement result is corrected in combination with the known mapping relationship between the confining pressures and the confining pressure influence coefficient, so that the measurement precision of the secondary stress of the hole wall surrounding rock can be greatly improved without using regional tectonic stress for estimation.

This invention relates to the field of existing tunnel engineering technology, specifically to a method for measuring the internal forces of existing tunnel lining structures. The method includes: setting up a measurement space within the tunnel; locating a first measurement point and a second measurement point within the measurement space; drilling a first core borehole and a first measuring small borehole at the first measurement point along a direction perpendicular to the tunnel lining surface; drilling a first hollow concrete cylinder including the first measuring small borehole and a second hollow concrete cylinder including the second measuring small borehole; drilling until the readings no longer change with drilling depth; removing the first and second hollow concrete cylinders and rereading all strain gauge readings. This method for measuring the internal forces of existing tunnel lining structures can accurately assess the stress state of the tunnel structure, providing a basis for developing remediation plans for the tunnel structure.

To provide strain gauges that do not require amplification circuits or power supplies.SOLUTION: A strain gauge 100 has a heterojunction photoelectric conversion element 10 and electrode pairs 21,22 that sandwich the heterojunction photoelectric conversion element, and at least one of the P-type semiconductor 12 and N-type semiconductor 11 at the PN junction of the heterojunction photoelectric conversion element is a piezoelectric semiconductor.SELECTED DRAWING: Figure 1

The invention relates to the technical field of ground stress measurement, and discloses a protolith stress measurement method suitable for weakly cemented soft rock disintegrated when meeting cementized.The protolith stress measurement method comprises the steps that compressed air is used for replacing water to serve as a powder discharging medium, and drilling construction is conducted; in the drilling process, the drilling area is cooled through a cooling medium, and the temperature is monitored to keep the rock mass temperature constant; installing a hollow inclusion strain gauge in the drill hole; drilling a rock core under a water-free condition, and completely taking out the rock core; according to the strain change measured by the hollow inclusion strain gauge before and after coring, the stress value of the protolith is calculated. According to the method, a dry drilling process of discharging powder by compressed air and controlling temperature by liquid nitrogen is adopted, so that the contact between water and weakly cemented soft rock is thoroughly avoided, and drilling and coring can be smoothly implemented on a stratum which cannot be subjected to primary rock stress measurement originally and is disintegrated when meeting cement.