Concrete stress monitoring method and device
By designing a concrete stress monitoring device including sleeves, load bearing plates, isolation plates, sensors, and connectors, the problem of difficulty in directly measuring concrete load stress in the prior art is solved, and high-precision stress monitoring is achieved, errors are eliminated and the impact of concrete deformation is offset.
Patent Information
- Application Number
- CN202510256920.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2025-05-27
AI Technical Summary
The prior art is difficult to directly measure stress under load in concrete structures, and indirect strain measurement methods are prone to introduce errors, making it difficult to distinguish between stresses caused by load stress and other deformations.
A concrete stress monitoring device is designed, including a sleeve, a load bearing plate, an isolation plate, a sensor, a first connector and a second connector. Direct measurement of stress is achieved by isolating the concrete in the inner cavity of the sleeve from the external concrete and using the connector to transmit load stress to the sensor.
The device can directly measure the load-acting stress of the concrete structure, eliminate the errors introduced by strain measurement, improve the test accuracy, and automatically offset the shrinkage and other deformation of concrete to ensure the accuracy of the measurement results.
Smart Images
Figure CN120043662A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of civil engineering testing technologies, and particularly to a method and device for monitoring concrete stress. Background Art
[0002] Since the stress-strain state of concrete is relatively complex and there are many influencing factors, in engineering inspections, the stress of concrete is usually measured indirectly through strain. Since it is difficult to distinguish which factor affects the strain during the strain measurement process, it is also difficult to distinguish the stress corresponding to the measured strain. For example, plastic deformation that causes volume change of the casting body before the initial setting and hardening of concrete, chemical shrinkage deformation and temperature deformation under long-term hydration after concrete casting and setting, creep deformation and normal load deformation of concrete under the action of service stress, etc. These influencing factors include some chemical actions (such as shrinkage and creep), some environmental actions (such as temperature, wind, snow, vibration, etc.), some self-weight and service load actions, and so on. In the prior art methods for indirectly measuring concrete stress by strain, since the strain measured by the sensor includes the action effect of the load and the comprehensive effects of temperature, shrinkage and creep, the calculated stress is also a comprehensive stress, and it is difficult to independently separate the service load effect of the concrete structure from the comprehensive effect.
[0003] The stress-strain change under load is the most intuitive manifestation of structural performance inspection. If stress is measured by strain and the elastic modulus at the corresponding time, it will inevitably increase the cost of obtaining the true value of the elastic modulus and the uncertainty of the test results introduced by the comprehensive strain, and some deformations of the structure do not generate stress. In some application scenarios of actual projects, such as the pressure test for the acceptance of the containment construction of nuclear power plants and the in-service performance acceptance pressure test of the structure during subsequent operation, as well as the safety monitoring of the change in the bottom stress of the dam caused by the rise and fall of the water level, etc., it is necessary to know the change in the structural mechanical properties caused by the load change. Therefore, direct stress measurement becomes very meaningful.
[0004] Many methods for measuring the stress of concrete structures have been proposed in the prior art, and each method has its specific application scenarios, advantages and disadvantages. Conventional methods include:
[0005] 1. Strain electrical measurement method: Measure the internal / surface strain of the structure by embedding or surface-pasting strain gauges / strain gauges, and calculate the stress in combination with the established theory and measured elastic modulus of concrete.
[0006] 2. Ultrasonic method: Calculate the stress by measuring the change in the propagation speed of ultrasonic waves in the material. This method often requires measuring the acoustoelastic coefficient of concrete, and the acoustoelastic coefficient of concrete ultrasonic waves is not a fixed coefficient. For this inhomogeneous viscoelastic-plastic material like concrete, the acoustoelastic coefficient may be affected by various factors, including the constituent materials of concrete, technological conditions, internal quality, and external environment during testing. In practical applications, the acoustoelastic coefficient is usually determined through experiments.
[0007] 3. Fiber Bragg grating strain method: Use Fiber Bragg grating sensors to measure the strain of the structure. In essence, it is equivalent to the strain electrical measurement method, except that the working principles of the sensors used are different.
[0008] 4. Pressure cell detection method: Use embedded pressure cells to directly measure the compressive stress of concrete. This method cannot measure tensile stress, and the measured compressive stress contains components of shrinkage stress.
[0009] The above-mentioned first and third methods are indirect methods for measuring stress through strain in the prior art. Usually, based on the strain changes measured by strain gauges and combined with the elastic modulus of concrete, the corresponding stress is calculated. In engineering practice, since the measured strain may include deformations that do not generate stress; moreover, the deformation may also include other non-force deformations such as shrinkage; in addition, concrete itself undergoes hydration and will shrink and expand to a certain extent with environmental changes, and creep will occur under the action of continuous loads, and the elastic modulus of concrete also changes with time. Therefore, calculating the actual stress of concrete through strain and the elastic modulus at a specific time will increase the error of the measurement results and make the finally calculated stress inaccurate. Although the fourth method can directly measure the pressure, the measured is the comprehensive pressure, still unable to distinguish the load stress, and at the same time, it cannot measure the tensile stress. Summary of the Invention
[0010] In view of this, the present application provides a method and device for monitoring concrete stress, so as to directly monitor the concrete stress of a concrete structure.
[0011] The technical solution of the present application is specifically implemented as follows:
[0012] A concrete stress monitoring device, the device includes: a sleeve, a bearing plate, a partition plate, a sensor, a first connecting member, and a second connecting member;
[0013] The bearing plate and the partition plate are respectively arranged at both ends of the sleeve, so as to form an independent cavity inside the sleeve;
[0014] The sensor is arranged in the cavity of the sleeve, and the rear end of the sensor is fixedly connected to the bearing plate;
[0015] The first connecting member is inserted through the partition board. The rear end of the first connecting member is located in the cavity of the sleeve, and the front end of the first connecting member is located outside the sleeve.
[0016] The second connecting member is arranged in the cavity of the sleeve. The rear end of the second connecting member is fixedly connected to the front end of the sensor, and the front end of the second connecting member is a free end.
[0017] Preferably, the first connecting member and the second connecting member are Y-shaped connecting screws.
[0018] Preferably, the ratio of the length of the first connecting member extending into the concrete in the inner cavity of the sleeve to the diameter of the concrete in the inner cavity of the sleeve is a preset first ratio.
[0019] The ratio of the length of the second connecting member extending into the concrete in the inner cavity of the sleeve to the diameter of the concrete in the inner cavity of the sleeve is a preset second ratio.
[0020] Preferably, the sleeve and the bearing plate are connected by bonding.
[0021] The sleeve and the partition board are connected by sleeving.
[0022] Preferably, the rear end of the sensor and the bearing plate are fixedly connected by welding.
[0023] Alternatively, the sensor and the bearing plate are formed by integral molding.
[0024] Preferably, the sensor is a force sensor or a pressure cell.
[0025] Preferably, the force sensor is a vibrating wire force sensor, a resistive force sensor or a fiber Bragg grating force sensor.
[0026] Preferably, the pressure cell is a vibrating wire pressure cell, a resistive pressure cell or a fiber Bragg grating pressure cell.
[0027] Preferably, the sleeve adopts a thin-wall structure.
[0028] The sleeve is a filter made of a material that is both breathable and water-permeable.
[0029] In this application, a concrete stress monitoring method is also proposed. The method includes:
[0030] When pouring concrete for the concrete structure to be monitored, open the partition board on the above-mentioned concrete stress monitoring device, so that the inner cavity of the sleeve is filled with corresponding concrete and vibrated compactly.
[0031] Insert the first connecting piece of the concrete stress monitoring device into the concrete in the inner cavity of the sleeve, fill the concrete in the sleeve, and then install and fix the isolation plate at one end of the sleeve.
[0032] Install the above-mentioned concrete stress monitoring device in the preset main stress direction of the concrete structure to be monitored.
[0033] Cure the concrete inside the sleeve and the concrete outside the sleeve under the same conditions.
[0034] Monitor the stress of the concrete of the concrete structure to be monitored according to the measurement data of the sensor.
[0035] As can be seen above, in the concrete stress monitoring method and device in the present application, since a sleeve, a bearing plate, an isolation plate, a sensor, a first connecting piece and a second connecting piece are provided in the concrete stress monitoring device, the concrete in the inner cavity of the sleeve can be isolated from the concrete outside, forming a relatively independent structure; the first connecting piece can be used to connect the external concrete and the internal core concrete, and transfer the force value or stress of the external concrete to the internal core concrete; the second connecting piece can connect the sensor and the internal core concrete, so that the force value or stress of the internal core concrete can be transferred to the sensor; the bearing plate can transfer the force value or stress of the internal core concrete to the external concrete, and can evenly transfer the load of the external concrete to the sensor; the sensor can measure the force value or stress of the internal core concrete and obtain corresponding measurement data. Therefore, the concrete stress of the concrete structure to be monitored can be directly monitored according to the measurement data of the sensor. Since the shrinkage and other deformations of the concrete inside and outside the sleeve can be automatically offset without affecting the measurement result of the load action, the concrete stress monitoring method and device in the present application have the direct measurement ability of the stress change of the load action. Description of the Drawings
[0036] Figure 1 It is a schematic structural diagram of the concrete stress monitoring device in a specific embodiment of the present application.
[0037] Figure 2 It is a schematic structural diagram of the concrete stress monitoring device in another specific embodiment of the present application.
[0038] Figure 3 It is a schematic flow diagram of the concrete stress monitoring method in a specific embodiment of the present application. Detailed Embodiments
[0039] To make the technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the drawings and specific embodiments.
[0040] Figure 1 Schematic diagram of the concrete stress monitoring device in the specific embodiment of the present application. As Figure 1 shown, the concrete stress monitoring device in the specific embodiment of the present application may include: a sleeve 11, a bearing plate 12, a separator plate 13, a sensor 14, a first connecting member 15 and a second connecting member 16;
[0041] The bearing plate and the separator plate are respectively arranged at both ends of the sleeve, so as to form an independent cavity inside the sleeve;
[0042] The sensor is arranged in the cavity of the sleeve, and the rear end of the sensor is fixedly connected to the bearing plate;
[0043] The first connecting member is inserted through the separator plate, the rear end of the first connecting member is located inside the cavity of the sleeve, and the front end of the first connecting member is located outside the sleeve;
[0044] The second connecting member is arranged inside the cavity of the sleeve, the rear end of the second connecting member is fixedly connected to the front end of the sensor, and the front end of the second connection is a free end.
[0045] In the technical solution of the present application, when the above-mentioned concrete stress monitoring device is used, when the concrete structure or component to be monitored is poured with concrete, the isolation plate on the above-mentioned concrete stress monitoring device can be opened, so that the corresponding concrete (i.e., concrete equivalent to the concrete structure or component to be monitored) is filled in the internal cavity of the sleeve, and the concrete in the internal cavity of the sleeve is vibrated and compacted. Subsequently, the first connecting member is inserted into the concrete in the internal cavity of the sleeve, the concrete in the sleeve is filled, and the concrete in the internal cavity of the sleeve is vibrated and compacted, and then the isolation plate is installed, so that the isolation plate is installed at one end of the sleeve and fixed, so that the concrete in the internal cavity of the sleeve is isolated from the external concrete, forming a relatively independent structure, which can be called internal core sample concrete (i.e., concrete in the internal cavity of the sleeve). Then, the above-mentioned concrete stress monitoring device is installed in the preset main force direction of the concrete structure or component to be monitored. The internal core sample concrete, as a part of the entire structure, is in the same environment as the external concrete. Therefore, when the concrete outside the sleeve is cured, it is equivalent to curing the concrete inside the sleeve under the same conditions. Therefore, the concrete inside and outside the sleeve can be in the same state while maintaining relative independence and isolation. The front end of the first connecting member is set in the concrete outside, and the rear end is set in the internal core concrete. Therefore, the first connecting member can be used to connect the external concrete and the internal core concrete, so as to transfer the force value or stress of the external concrete to the internal core concrete. In addition, the load-bearing plate set at the other end of the sleeve has sufficient rigidity and an enlarged cross-sectional portion, which can be used to transfer the force value or stress of the internal core concrete to the external concrete, and can evenly transfer the load of the external concrete to the sensor. The front end of the sensor is in direct contact with the internal core concrete, and the rear end of the second connecting member is welded to the front end of the sensor structure. The front end is equivalent to being inserted into the internal core concrete, so that the sensor and the internal core concrete can be connected, so that the force value or stress of the internal core concrete can be transferred to the sensor. The sensor can measure the force value or stress transmitted from the internal core concrete; if the internal core concrete transmits a force value, the stress of the internal core concrete can be directly calculated according to the force value and the area of action of the force value.
[0046] For example, suppose the stress of the concrete outside the sleeve and the stress of the concrete inside the core are σ 1 and σ 2 , in general, σ 1 and σ 2The difference between them is very small and can be ignored. Therefore, the stress of the concrete in the internal core sample measured can be equated to the stress of the concrete outside the sleeve. So, it can be assumed that the stress of the concrete outside the sleeve and the stress of the concrete in the internal core sample are σ, the acting force on the concrete in the internal core sample is F, and the stress area of the concrete in the internal core sample is A (the sleeve can adopt a thin-walled structure, so its weakening of the acting area and its own influence on force transmission can be ignored). Then, we can get: σ = F / A.
[0047] Since the sensor can measure the force value or stress of the concrete in the internal core sample and obtain corresponding measurement data, therefore, by acquiring the measurement data of the sensor, the stress monitoring of the concrete can be carried out. Since the deformations such as shrinkage of the concrete inside and outside the sleeve can be automatically offset without affecting the measurement result of the load action, the above-mentioned concrete stress monitoring device can be used to monitor the stress of the corresponding concrete under the action of load change of the concrete structure to be monitored.
[0048] In addition, in the technical solution of the present application, the above-mentioned concrete stress monitoring method and device can be implemented through a variety of specific implementation manners. The following will take several of these specific manners as examples to introduce the technical solution of the present application in detail.
[0049] For example, as an example, in a specific embodiment of the present application, the sleeve 11 and the bearing plate 12 can be connected by an adhesive bonding method, or can be connected by other connection methods, which will not be listed one by one here.
[0050] For another example, as an example, in a specific embodiment of the present application, the sleeve 11 and the isolation plate 13 can be connected by a socket connection method, or can be connected by other connection methods, which will not be listed one by one here.
[0051] For another example, as an example, in a specific embodiment of the present application, the rear end of the sensor 14 and the bearing plate 12 can be fixedly connected by a welding method, or can be fixedly connected by other connection methods, or the sensor 14 and the bearing plate 12 can also be formed by an integral molding method.
[0052] For another example, as an example, in a specific embodiment of the present application, the rear end of the second connector 16 and the front end of the sensor 14 can be fixedly connected by a welding method, or can be fixedly connected by other connection methods.
[0053] In addition, as an example, in a specific embodiment of the present application, the sensor can be a force sensor or a pressure cell, or can be other suitable sensors, which will not be listed one by one here.
[0054] In addition, as an example, in a specific embodiment of the present application, the force sensor may be a vibrating-wire force sensor, a resistive force sensor, or a fiber grating force sensor, or other suitable force sensors, which are not listed here one by one.
[0055] In addition, as an example, in a specific embodiment of the present application, the pressure cell may be a vibrating-wire pressure cell, a resistive pressure cell, or a fiber grating pressure cell, or other suitable pressure cells, which are not listed here one by one.
[0056] In addition, as an example, Figure 2 As shown, in a specific embodiment of the present application, the first connecting member and the second connecting member may be a Y-shaped connecting screw, or other suitable connecting members, which are not listed here one by one.
[0057] In addition, as an example, in a specific embodiment of the present application, the sleeve may adopt a thin-wall structure, so as to reduce the influence of the sleeve and its inner wall on the measurement result.
[0058] In addition, as an example, in a specific embodiment of the present application, the sleeve can be a filter made of a material that is both air-permeable and water-permeable, thereby ensuring that the concrete inside and outside the sleeve are relatively independently isolated, and that environmental parameters or conditions such as temperature and humidity remain consistent.
[0059] In addition, as an example, in a specific embodiment of the present application, the ratio of the length of the first connecting member extending into the internal core concrete to the diameter of the internal core concrete is a preset first ratio, and the ratio of the length of the second connecting member extending into the internal core concrete to the diameter of the internal core concrete is a preset second ratio. By setting the above ratios and the type of the connecting member, it can be ensured that the first connecting member and the second connecting member can equally transmit the force value of the external concrete within the design range of the bearing capacity of the device, and at the same time, the contact surface between the connecting member and the concrete will not slip.
[0060] In the technical solution of the present application, the above-mentioned first ratio and second ratio can be pre-set according to the needs of the actual application scenario and the relevant requirements and / or standards of the professional field, and they are not listed one by one here.
[0061] Figure 3 FIG. 1 is a flow chart of the concrete stress monitoring method in the embodiment of the present application. Figure 3 As shown, the concrete stress monitoring method in the embodiment of the present application includes the following steps:
[0062] Step 201, when the concrete structure to be monitored is being poured with concrete, the isolation plate on the concrete stress monitoring device is opened, so that the inner cavity of the sleeve is filled with corresponding concrete and vibrated to be dense.
[0063] In the technical solution of the present application, when the concrete of the concrete structure to be monitored is poured, the inner cavity of the sleeve of the concrete stress monitoring device can also be filled with the corresponding concrete, so that the concrete in the inner cavity of the sleeve is the same as that in the concrete structure to be monitored, and the concrete inside and outside the sleeve is in the same state.
[0064] Step 202: Insert the first connector of the concrete stress monitoring device into the concrete in the inner cavity of the sleeve, fill the concrete in the sleeve, and then install and fix the isolation plate at one end of the sleeve.
[0065] In the technical solution of the present application, it is also necessary to insert the first connector of the concrete stress monitoring device into the concrete in the inner cavity of the sleeve, then fill the concrete in the sleeve, and vibrate the concrete in the inner cavity of the sleeve until it is dense. Subsequently, install and fix the isolation plate at one end of the sleeve to seal the sleeve, so that the concrete in the inner cavity of the sleeve is isolated from the external concrete, forming a relatively independent structure, that is, the internal core concrete, and the front end of the first connector is arranged in the external concrete, and the rear end is arranged in the internal core concrete. Therefore, the external concrete and the internal core concrete can be connected through the first connector, so as to transfer the force value or stress of the external concrete to the internal core concrete.
[0066] Step 203: Install the above-mentioned concrete stress monitoring device in the preset main stress direction of the concrete structure to be monitored.
[0067] In the technical solution of the present application, the concrete stress monitoring device can be first set in the concrete structure to be monitored. Specifically, it can be installed in the preset main stress direction of the concrete structure to be monitored.
[0068] Step 204: Cure the concrete inside the sleeve and the concrete outside the sleeve under the same conditions.
[0069] In the technical solution of the present application, after the concrete stress monitoring device is set, since the concrete in the inner cavity of the sleeve is the same as that in the concrete structure to be monitored, and the concrete inside and outside the sleeve is in the same environment, when curing the concrete outside the sleeve, it is equivalent to curing the concrete inside the sleeve under the same conditions. Therefore, while the concrete inside and outside the sleeve remains relatively independently isolated, it can be in the same state.
[0070] Step 205: Monitor the stress of the concrete of the concrete structure to be monitored according to the measurement data of the sensor.
[0071] In the technical solution of the present application, since the sensor can measure the force value or stress of the internal core concrete and obtain corresponding measurement data, the measurement data of the sensor can be acquired, and the stress monitoring of the concrete structure to be monitored can be carried out based on the measurement data of the sensor.
[0072] For example, since the concrete inside the sleeve is in the same state as the concrete outside the sleeve, the load of the concrete outside the sleeve can transfer the corresponding stress to the concrete inside the sleeve (i.e., the internal core concrete) through the first connecting member, and then transfer the corresponding stress to the sensor through the second connecting member. The sensor can measure the force value or stress transferred from the internal core concrete; if the force value transferred from the internal core concrete is measured, the stress of the internal core concrete can be directly calculated according to the force value and the acting area of the force value. Therefore, the sensor can measure the force value or stress of the internal core concrete and obtain corresponding measurement data, so that the stress monitoring of the concrete structure to be monitored can be carried out based on the measurement data of the sensor.
[0073] In addition, as an example, in a specific embodiment of the present application, the cable of the sensor can be led out and connected to the data processing device, so that the data processing device can acquire the measurement data of the sensor through the cable, and thus the stress monitoring of the concrete structure to be monitored can be carried out based on the measurement data of the sensor.
[0074] Therefore, through the above steps 201 to 205, the above concrete stress monitoring device can be used to monitor the stress of the corresponding concrete under the action of load change of the concrete structure to be monitored, and the deformation such as shrinkage inside and outside the sleeve of the concrete itself can be offset without affecting the measurement result of the load action.
[0075] In summary, in the technical solution of the present application, since a sleeve, a bearing plate, a partition plate, a sensor, a first connecting member, and a second connecting member are provided in the concrete stress monitoring device, the concrete in the inner cavity of the sleeve can be isolated from the external concrete to form a relatively independent structure; the first connecting member can be used to connect the external concrete and the inner core concrete, and transfer the force value or stress of the external concrete to the inner core concrete; the second connecting member can connect the sensor to the inner core concrete, so that the force value or stress of the inner core concrete can be transferred to the sensor; the bearing plate can transfer the force value or stress of the inner core concrete to the external concrete, and evenly transfer the load of the external concrete to the sensor; the sensor can measure the force value or stress of the inner core concrete and obtain corresponding measurement data. Therefore, the concrete stress of the concrete structure to be monitored can be directly monitored according to the measurement data of the sensor. Since the deformations such as shrinkage of the concrete inside and outside the sleeve can be automatically offset without affecting the measurement result of the load effect, the concrete stress monitoring method and device in the present application have the ability to directly measure the stress change under the load effect.
[0076] In the technical solution of the present application, the stress of concrete can be directly measured by the above-mentioned concrete stress monitoring method and device, rather than by indirect measurement through strain. Therefore, various errors introduced by strain measurement can be eliminated, and the test accuracy can be effectively improved; moreover, the technical solution of the present application can be used not only for compressive stress measurement but also for tensile stress measurement. In addition, the concrete stress monitoring device in the present application can directly offset the non-loading deformation stress of concrete (for example, the stress generated by the self-volume deformation of concrete), correct the temperature deformation stress under the constraint effect, and the measured stress is the stress under the action of the service load; moreover, it does not need to cooperate with the measurement of the non-stress gauge, and the device itself can eliminate the deformation (such as shrinkage and creep) that does not generate stress and needs to be measured by the non-stress gauge in the indirect strain measurement. In addition, the stress measured by the technical solution of the present application is the value caused by the action of the structural and / or component load. For the performance evaluation of the structure, such as the construction acceptance of the containment and the pressure test during in-service acceptance, it has the most direct effect on inspecting the mechanical performance of the containment and is also a two-way inspection of the loading value. Moreover, the concrete stress monitoring device of the present application no longer has excessive requirements on the state of the concrete, and no longer requires that the elastic modulus of the concrete is constant or needs to give the measured value through additional experiments. At the same time, the inner core concrete in the concrete stress monitoring device of the present application uses the same concrete as the structure to be measured, and has the same characteristics such as shrinkage, expansion, elastic modulus change, temperature correlation, and potential creep, etc. Therefore, it can ensure that the measured stress is representative. In addition, the concrete stress monitoring device of the present application can achieve the equivalent transfer of the external force value through the connecting member, so that the monitoring of the external stress can be equivalently replaced by the measurement of the internal stress.
[0077] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.
Claims
1. A concrete stress monitoring device, characterized in that: The device comprises: a sleeve, a bearing plate, an isolation plate, a sensor, a first connecting member and a second connecting member; The bearing plate and the isolation plate are respectively arranged at two ends of the sleeve so that an independent cavity is formed inside the sleeve; The sensor is arranged in the cavity of the sleeve, and the rear end of the sensor is fixedly connected to the bearing plate; The first connecting member is inserted into the isolation plate, the rear end of the first connecting member is located in the cavity of the sleeve, and the front end of the first connecting member is located outside the sleeve; The second connecting member is arranged in the cavity of the sleeve, the rear end of the second connecting member is fixedly connected to the front end of the sensor, and the front end of the second connection is a free end.
2. The device according to claim 1, characterized in that: The first connecting member and the second connecting member are Y-shaped connecting screws.
3. The device according to claim 1 or 2, characterized in that: The ratio of the length of the first connecting member extending into the concrete in the inner cavity of the sleeve to the diameter of the concrete in the inner cavity of the sleeve is a preset first ratio; The ratio of the length of the second connecting member extending into the concrete in the inner cavity of the sleeve to the diameter of the concrete in the inner cavity of the sleeve is a preset second ratio.
4. The device according to claim 1, characterized in that: The sleeve is connected to the bearing plate by bonding; The sleeve is connected to the isolation plate by sleeve connection.
5. The device according to claim 1, characterized in that: The rear end of the sensor is fixedly connected to the bearing plate by welding; Alternatively, the sensor and the load-bearing plate are formed in one piece.
6. The device according to claim 1, characterized in that: The sensor is a force sensor or a pressure cell.
7. The device according to claim 6, characterized in that: The force sensor is a vibrating-wire force sensor, a resistive force sensor or a fiber grating force sensor.
8. The device according to claim 7, characterized in that: The pressure cell is a vibrating-wire pressure cell, a resistive pressure cell or a fiber grating pressure cell.
9. The device according to claim 1, characterized in that: The sleeve adopts a thin-wall structure; The sleeve is a filter made of a material that is both air-permeable and water-permeable.
10. A method for monitoring concrete stress, characterized in that: The method includes: When the concrete structure to be monitored is being poured with concrete, the isolation plate on the concrete stress monitoring device according to any one of claims 1 to 9 is opened, so that the internal cavity of the sleeve is filled with corresponding concrete and vibrated to be dense; Inserting the first connecting piece of the concrete stress monitoring device into the concrete in the inner cavity of the sleeve to fill the inner cavity of the sleeve with concrete, and then installing the isolation plate at one end of the sleeve and fixing it; Install the above concrete stress monitoring device in the preset main force direction of the concrete structure to be monitored; The concrete inside the sleeve is cured under the same conditions as the concrete outside the sleeve; The concrete stress of the concrete structure to be monitored is monitored according to the measurement data of the sensor.