A method, system, device, and medium for testing strain of steel considering local bond stress effect

Abstract

This invention relates to the field of civil engineering technology, specifically providing a method, system, equipment, and medium for testing the strain of reinforcing steel bars considering the effect of local bond stress. The method includes: acquiring the parameters of the reinforcing steel bar to be tested and the specifications of the strain gauges; grinding the surface of the reinforcing steel bar to form a grinding plane according to the strain gauge specifications; attaching the strain gauges to the grinding plane and setting a protective layer for the strain gauges; threading the strain gauge wires through a wire protection device and fixing the wire protection device to complete the layout of a single measuring point; confirming the evaluation index of the weakening effect of the steel bar grinding; calculating the weakening ratio of the stress performance of the reinforcing steel bar by a single measuring point; calculating the maximum number of measuring points that can be arranged on a single reinforcing steel bar; arranging multiple measuring points along the axial direction of the reinforcing steel bar; and connecting the strain gauges at multiple measuring points to a strain measurement device to acquire the strain signal of the reinforcing steel bar in real time. Using the testing method of this invention, strain data from multiple measuring points can be acquired while meeting the requirements for the stress performance of the reinforcing steel bar, improving the accuracy of the measurement results.

Description

Technical Field

[0001] This invention relates to the field of civil engineering technology, and specifically to a method, system, equipment, and medium for testing the strain of reinforcing steel bars that takes into account the effect of local bond stress. Background Technology

[0002] Currently, there are two main methods for measuring the strain of reinforced concrete structures in indoor tests: installing a rebar gauge and attaching strain gauges. The first method, using a rebar gauge, significantly alters the shape of the rebar, strengthening the bond between the rebar and concrete, thus resulting in an underestimation of strain values ​​during actual testing. The second method, attaching strain gauges, often involves deep grooves in the rebar, which also significantly affects the rebar's load-bearing capacity, leading to distorted strain measurements. Furthermore, current techniques for protecting the measuring points often use insulating tape, which weakens the bond stress and results in overestimating strain values. In practical engineering applications, especially under complex stress conditions, the shortcomings of these two methods become more pronounced, leading to inaccurate measurement results.

[0003] In summary, there is an urgent need to provide a method, system, equipment, and medium for testing the strain of reinforcing bars that takes into account the effect of local bond stress, in order to solve the technical problems existing in the prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a method, system, device, and medium for testing the strain of reinforcing bars that takes into account the effect of local bond stress, so as to solve the technical problems existing in the prior art. The specific technical solution is as follows:

[0005] A method for testing the strain of reinforcing steel bars that takes into account the effect of local bond stress includes the following steps:

[0006] S1. Obtain the parameters of the steel reinforcement under test and the specifications of the strain gauge;

[0007] S2. According to the specifications of the strain gauge, determine a grinding area on one side of the longitudinal rib on the surface of the tested steel bar, and grind the area to form a grinding plane.

[0008] S3. Attach the strain gauge to the polished surface and set a strain gauge protective layer on the outer surface of the attached strain gauge;

[0009] S4. Insert the strain gauge wire into the wire protection device, and fix the wire protection device along the axis of the steel bar to be measured to one side of the longitudinal rib of the steel bar to complete the layout of a single measuring point;

[0010] S5. Evaluation indicators to confirm the weakening effect of rebar grinding. ; Calculate the reduction ratio of the stress performance of the tested steel bar by a single measuring point. ;

[0011] S6. Calculate the maximum number of measuring points that can be arranged on a single tested steel bar. ;

[0012] S7. Arrange multiple measuring points along the axial direction of the reinforcing bar being measured, following steps S1 to S4, with the number of measuring points not exceeding [number missing]. ;

[0013] S8. Connect the strain gauges at multiple measuring points to the strain measurement equipment to acquire the strain signal of the steel reinforcement in real time.

[0014] Furthermore, the surface of the tested reinforcing bar has one or at least two measuring points along one side of the longitudinal rib;

[0015] The grinding plane, strain gauge, and strain gauge protective layer are arranged one-to-one to form a single measuring point; the strain gauge protective layer includes a liquid insulating adhesive layer coated on the outer surface of the strain gauge.

[0016] Furthermore, in S2, the dimensions of the grinding surface are required as follows:

[0017] , ;

[0018] in: To grind the length of the flat surface; To grind the width of the surface; The length of the strain gauge; The width of the strain gauge;

[0019] Grinding depth for:

[0020] ;

[0021] in: The radius of the steel bar being measured is... The width of the strain gauge is in mm.

[0022] Furthermore, evaluation indicators for the weakening effect of rebar grinding. for:

[0023] ;

[0024] in: This refers to the anchorage length of the steel reinforcement after grinding. This refers to the anchorage length of the reinforcing steel bar before grinding. This is the reduction factor for the steel reinforcement section. This is the weakening coefficient for the bond performance of steel bars; To take the absolute value;

[0025] The percentage reduction in the stress performance of the tested steel reinforcement by a single measuring point yes:

[0026] .

[0027] Furthermore, S6 specifically refers to:

[0028] S6.1, The reduction ratio of the stress performance of the tested steel bar based on a single measuring point ,calculate The reduction ratio of the stress performance of the tested steel bar at each measuring point :

[0029] ;

[0030] ;

[0031] in: This refers to the effective bond length of the reinforcing steel. The ratio of the length of the grinding plane of a single strain gauge to the effective bond length of the tested reinforcing bar along the reinforcing bar axis;

[0032] S6.2 Calculate the maximum number of measuring points that can be arranged on a single reinforcing bar being tested. Specifically:

[0033] Let the maximum allowable weakening ratio of a single tested steel bar be... ,but:

[0034] ;

[0035] The maximum number of measurement points for:

[0036] ;

[0037] in, This indicates rounding down to the nearest integer.

[0038] A strain testing system for reinforcing bars that considers the effect of local bond stress is used to implement the testing method described above. It includes one or at least two measuring points arranged along the axial direction of the reinforcing bar to be tested, spaced apart. Each measuring point includes a grinding surface, a strain gauge, and a strain gauge protective layer sequentially arranged on the reinforcing bar to be tested. The surface of the reinforcing bar to be tested has a grinding surface formed by grinding along one side of the longitudinal rib. The strain gauge is fixed to the grinding surface by an adhesive layer. The strain gauge protective layer is disposed on the outer surface of the strain gauge.

[0039] Furthermore, it also includes a conductor protection device, which is sleeved on the outside of the strain gauge conductor and arranged along the axial direction of the tested reinforcing bar and fixed to one side of its longitudinal rib.

[0040] The conductor protection device includes a capillary stainless steel tube; the outer diameter of the capillary stainless steel tube is not greater than the diameter of the reinforcing bar. 10% of the thickness, but not less than 1.5mm, if 10% If ≤ 1.5mm, then take 1.5mm.

[0041] Furthermore, the strain gauge protective layer comprises at least two layers of cured liquid insulating adhesive.

[0042] An electronic device includes a memory and a processor, the memory storing a computer program; the processor executes the computer program to implement the steel bar strain testing method considering the local bond stress effect as described above.

[0043] A readable storage medium storing a computer program, wherein a processor executes the computer program to implement the steel bar strain testing method considering the local bond stress effect as described above.

[0044] The application of the technical solution of the present invention has the following beneficial effects:

[0045] (1) The present invention provides a method for testing the strain of reinforcing bars considering the effect of local bond stress. The method includes: S1, obtaining the parameters of the reinforcing bar to be tested and the specifications of the strain gauge; S2, determining a grinding area on one side of the longitudinal rib of the reinforcing bar to be tested according to the specifications of the strain gauge, and grinding the area to form a grinding plane; S3, pasting the strain gauge onto the grinding plane, and setting a strain gauge protective layer on the outer surface of the pasted strain gauge; S4, threading the strain gauge wire into the wire protection device, and fixing the wire protection device along the axial direction of the reinforcing bar to one side of the longitudinal rib of the reinforcing bar to complete the layout of a single measuring point; S5, confirming the evaluation index of the weakening effect of the reinforcing bar grinding. ; Calculate the reduction ratio of the stress performance of the tested steel bar by a single measuring point. S6. Calculate the maximum number of measuring points that can be arranged on a single reinforcing bar being tested. S7. Arrange multiple measuring points along the axial direction of the reinforcing bar being measured, following steps S1 to S4, with the number of measuring points not exceeding [number missing]. S8. Connect strain gauges at multiple measuring points to a strain measurement device to acquire the strain signal of the reinforcing steel in real time. Using the testing method of this invention, strain data from multiple measuring points can be acquired while simultaneously meeting the stress performance requirements of the reinforcing steel, thus improving the accuracy of the measurement results.

[0046] (2) When the strain gauge is fixed in the traditional way (i.e., the measuring point is protected by wrapping the reinforcing bar with tape), the bond force transfer between the reinforcing bar and the concrete in the wrapped section is completely cut off, causing the axial force of the reinforcing bar in that section to no longer decrease along the length direction. The measured strain of the reinforcing bar will be significantly greater than the actual stress strain of the structure, resulting in a systematic false high error. In this invention, a grinding plane is set along one side of the longitudinal rib of the reinforcing bar being measured. Each grinding plane corresponds to a strain gauge, and liquid insulating glue is coated on the outer surface of the strain gauge for single-point protection. This method effectively increases the contact area between the reinforcing bar and the concrete, has little impact on the overall bond continuity between the two, and its impact on the bond stress and axial force transfer is only a high-order small quantity. Therefore, the measured strain of the reinforcing bar can truly reflect the actual stress state of the reinforcing bar in the structure.

[0047] (3) This invention provides a steel bar strain testing system considering the effect of local bond stress, comprising one or at least two measuring points arranged along the axial direction of the steel bar to be tested, and at intervals thereof; each measuring point includes a grinding surface, a strain gauge, and a strain gauge protective layer sequentially arranged on the steel bar to be tested; the surface of the steel bar to be tested has a grinding surface formed by grinding along one side of the longitudinal rib; the strain gauge is fixed to the grinding surface by an adhesive layer; the strain gauge protective layer is disposed on the outer surface of the strain gauge. The testing system of this invention, by setting a grinding surface to install the strain gauge and setting a strain gauge protective layer for each strain gauge, reduces the weakening of the bond stress of the steel bar compared with the traditional method, ensures the stress performance of the steel bar itself, and makes the measurement results more realistic and accurate.

[0048] (4) The present invention also includes a conductor protection device, which is sleeved on the outside of the strain gauge conductor and arranged along the axial direction of the tested steel bar and fixed on one side of its longitudinal rib. By setting the conductor protection device, the strain gauge conductor can be effectively protected, avoiding problems such as wire breakage in the casting environment of complex structures (such as semi-prefabricated structures), and improving the survival rate of the strain gauge.

[0049] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0050] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0051] Figure 1 This is a diagram showing the arrangement of multiple measuring points for the reinforcing steel bars being measured in this invention;

[0052] Figure 2 yes Figure 1A cross-sectional view of the location of the measuring point in the middle;

[0053] Figure 3 yes Figure 2 Detailed view;

[0054] Figure 4 These are schematic diagrams of the localized bond stress release phenomenon based on the strain gauge protective layer; wherein, (a) is a schematic diagram based on the traditional strain gauge protective layer, and (b) is a schematic diagram based on the strain gauge protective layer of the present invention.

[0055] Figure 5 This is a flowchart of the steel bar strain testing method considering the local bond stress effect in this invention;

[0056] Among them, 1. Concrete, 2. Reinforcing steel being tested, 3. Conductor protection device, 4. Strain gauge conductor, 5. Grinding surface, 6. Strain gauge, 7. Strain gauge protective layer, 8. Insulating tape. Detailed Implementation

[0057] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0058] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0059] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0060] Example:

[0061] See Figures 1-3 This embodiment provides a steel bar strain testing system that considers the effect of local bond stress, including multiple measuring points arranged along the axial direction of the steel bar 2 being tested; each measuring point includes a grinding surface 5, a strain gauge 6, and a strain gauge protective layer 7 sequentially arranged on the steel bar 2 being tested;

[0062] In this embodiment, the tested reinforcing bar 2 is a stressed reinforcing bar in a reinforced concrete structure. A strain measuring point grinding area is set on one side of the longitudinal rib of the reinforcing bar 2. The grinding area is locally micro-grinded and leveled using a grinding wheel machine, so that the surface of the reinforcing bar forms a grinding plane 5 that matches the size of the strain gauge 6. This is to ensure reliable adhesion between the strain gauge 6 and the reinforcing bar substrate, while avoiding the impact of large-scale grooving on the cross-section and bonding performance of the reinforcing bar.

[0063] The strain gauge 6 is fixed to the polished surface 5 by an adhesive layer (such as quick-drying glue or 502 glue), which achieves a firm bond between the strain gauge sensitive grid and the steel reinforcement substrate, so that the strain gauge 6 can synchronously reflect the real strain response of the steel reinforcement under tension, compression and combined action.

[0064] The strain gauge protective layer 7 is disposed on the outer surface of the strain gauge 6. In this embodiment, the strain gauge protective layer 7 is formed by coating liquid insulating adhesive layer by layer. Preferably, at least two layers of the liquid insulating adhesive are coated on the surface of the strain gauge 6. After the liquid insulating adhesive is cured, a flexible protective shell with waterproof, moisture-proof, vibration-proof and alkali corrosion-resistant capabilities is formed on the outside of the strain gauge 6 to prevent the strain gauge 6 from falling off, short-circuiting or failing in the concrete pouring, vibration and service environment.

[0065] When strain gauge 6 is protected with a protective layer, different protective measures will also affect the bond stress during the reinforcement loading process. See Figure 4 When the traditional method is used, that is, the measuring point is protected by wrapping the reinforcing bar with insulating tape in a full circle, the bond force transmission between the reinforcing bar and the concrete in the wrapped section is completely cut off. As a result, the axial force of the reinforcing bar in that section no longer decreases along the length direction. The measured reinforcing bar strain will be significantly greater than the actual stress strain of the structure, resulting in a systematic false height error.

[0066] The present invention uses liquid insulating adhesive to partially cover a single strain gauge 6, which does not disrupt the overall bond continuity between the steel and concrete. Its influence on the bond stress and axial force transmission is only a small, high-order quantity. The measured steel strain can truly reflect the actual stress state of the steel in the structure. Compared with traditional protection methods, the strain results measured by the technical solution of the present invention are more accurate.

[0067] In this embodiment, a conductor protection device 3 is also included. The conductor protection device 3 is sleeved on the outside of the strain gauge conductor and is arranged along the axial direction of the tested reinforcing bar 2 and fixed to one side of its longitudinal rib. Preferably, the conductor protection device 3 includes a capillary stainless steel tube; the outer diameter of the capillary stainless steel tube is not greater than the diameter of the reinforcing bar. 10% of the thickness, but not less than 1.5mm, if 10% If the diameter is ≤1.5mm, then 1.5mm is chosen to minimize the impact on the bond performance between the reinforcing steel and concrete while ensuring the mechanical protection effect of the conductor. The strain gauge conductor is entirely inserted inside a capillary stainless steel tube, which is laid along the axis of the reinforcing steel and fixed to one side of the longitudinal rib of the reinforcing steel with wire. The top of the capillary stainless steel tube is bent according to the conductor lead-out path and passes through the concrete pouring formwork to achieve the nearest lead-out of the strain gauge conductor 4. In this embodiment, preferably, the outer diameter of the capillary stainless steel tube is 2.4mm and the wall thickness is 0.2mm, and the strain gauge conductor 4 is an enameled wire with a diameter of 0.5mm to facilitate insertion into the capillary stainless steel tube.

[0068] The steel bar strain testing system provided by this invention, which considers the effect of local bond stress, can reduce the weakening of bond stress in steel bars, ensure the stress performance of the steel bars themselves, improve the accuracy and authenticity of measurement results, meet the application requirements of complex engineering scenarios, and has strong applicability.

[0069] See Figure 5 This invention provides a method for testing the strain of reinforcing steel bars considering the effect of local bond stress, comprising the following steps:

[0070] S1. Obtain the parameters of the tested reinforcing bar and the specifications of the strain gauge; In this embodiment, the tested reinforcing bar 2 is a stressed reinforcing bar in a reinforced concrete structure.

[0071] S2. According to the strain gauge specifications, a grinding area is determined on one side of the longitudinal rib on the surface of the tested reinforcing bar 2, and this area is ground to form a grinding plane 5. In this embodiment, a strain gauge grinding area is set on one side of the longitudinal rib on the surface of the tested reinforcing bar 2. The grinding area is locally micro-grinded and leveled using a grinding wheel to form a grinding plane 5 that matches the size of the strain gauge on the surface of the reinforcing bar. This ensures reliable adhesion between the strain gauge and the reinforcing bar substrate, while avoiding the impact of large-scale grooving on the cross-section and bonding performance of the reinforcing bar. Preferably, the size of the grinding plane 5 is adjusted according to the size of the strain gauge. The grinding plane 5 needs to have a certain margin to facilitate the adhesion of the strain gauge. Its size requirements are as follows:

[0072] , ;

[0073] in: To grind the length of the flat surface; To grind the width of the surface, For the strain gauge length, The width of the strain gauge.

[0074] The grinding cross-section is arc-shaped, and the grinding depth is... for:

[0075] ;

[0076] in: The radius of the steel bar being measured is... The width of the strain gauge is in mm.

[0077] S3. Clean and polish the surface 5. Use a cotton ball soaked in acetone to clean the patch area until no stains are visible on the cotton ball. Clean in one direction only, do not wipe back and forth.

[0078] Use a pencil to mark the position where the strain gauge will be pasted on the polished surface 5. Clean the pasting area with an alcohol swab. Paste the strain gauge onto the polished surface 5 with quick-drying glue or 502 glue and press for 5-10 seconds.

[0079] After the strain gauge is pasted, two layers of liquid insulating adhesive are applied to its outer surface, with a time interval of no less than 10 minutes between the two layers. After curing, a flexible protective shell with waterproof, moisture-proof, vibration-proof and alkali-corrosion-resistant properties is formed on the outside of the strain gauge, which is the strain gauge protective layer.

[0080] S4. Insert the strain gauge wire into the capillary stainless steel tube and fix the capillary stainless steel tube along the axis of the steel bar being measured to one side of the longitudinal rib of the steel bar. Bend the top of the tube and lead the wire out from the designed path; complete the layout of a single measuring point.

[0081] In this embodiment, the surface of the tested steel bar has one or at least two measuring points along one side of the longitudinal rib; the grinding plane, strain gauge and strain gauge protective layer are set one-to-one to form a single measuring point.

[0082] S5. Evaluation indicators to confirm the weakening effect of rebar grinding. This refers to the proportion of weakened structural performance of the reinforcing steel; specifically as follows:

[0083] To ensure sufficient bond strength between reinforced concrete, the reinforcing bars must have a certain anchorage length within the concrete. The anchorage length of the reinforcing bars is calculated as follows:

[0084] ;

[0085] in: This refers to the anchorage length of the reinforcing bar. For the yield strength of the steel reinforcement, The cross-sectional area of ​​the reinforcing steel bar. The average bond strength of the reinforcing steel. The diameter of the reinforcing bar;

[0086] The surface of the reinforcing steel was ground and leveled during the embedding of strain gauges, which weakened its load-bearing capacity. On the one hand, it reduced the cross-sectional area of ​​the steel; on the other hand, it damaged the surface ribs, weakening its bond strength. The effective bond strength and effective cross-sectional area of ​​the reinforcing steel after grinding are calculated as follows:

[0087] , ;

[0088] in: The average bond strength of the steel bars after grinding. This is the weakening factor for the bond performance of steel bars. This represents the cross-sectional area of ​​the steel bar after grinding. This is the reduction factor for the steel reinforcement section;

[0089] The required rebar anchorage length after grinding is calculated as follows:

[0090] ;

[0091] in: This refers to the anchorage length of the steel reinforcement after grinding.

[0092] The proportion of the reduction in the load-bearing capacity of steel bars due to steel bar grinding. The calculation is as follows:

[0093] ;

[0094] in: This refers to the anchorage length of the steel reinforcement after grinding. This refers to the anchorage length of the reinforcing steel bar before grinding. This is the reduction factor for the steel reinforcement section. This is the weakening coefficient for the bond performance of steel bars; To take the absolute value;

[0095] Calculate the reduction ratio of the stress performance of the tested steel bar by a single measuring point. The details are as follows:

[0096] Reinforcement section weakening factor for:

[0097] ;

[0098] ;

[0099] in: This represents the cross-sectional area loss of the reinforcing steel. The radius of the steel bar being measured is... For polishing depth;

[0100] Reinforcement bond performance weakening factor for:

[0101] ;

[0102] ;

[0103] ;

[0104] in: This is the perimeter of the steel bar after grinding. This is the perimeter of the steel reinforcement before grinding. For the part corresponding to the central corner that needs to be polished, To polish the chord length corresponding to the bow-shaped area;

[0105] but ;

[0106] The reduction ratio of the stress performance of the tested steel bar by a single measuring point for:

[0107] .

[0108] S6. Calculate the maximum number of measuring points that can be arranged on a single tested steel bar 2. Specifically:

[0109] S6.1, The reduction ratio of the stress performance of the tested steel bar based on a single measuring point ,calculate The reduction ratio of the stress performance of the tested steel bar at each measuring point ;

[0110] Arrangement of the same reinforcing bar When measuring at each point, the total bond area of ​​the reinforcing steel is... , For the effective bond length of the reinforcing bars; arrangement At each measuring point, the total effective bonding area after grinding is ;

[0111] The bonding area attenuation coefficient is then:

[0112] ;

[0113] .

[0114] Throughout the entire reinforcing bar, the cross-sectional area lost after grinding the measuring points does not cumulatively increase with the increase of the reinforcing bar length, i.e. Furthermore, since all measuring points are ground individually, the impact on the cross-sectional area of ​​the reinforcing bars near the measuring points is negligible. ;

[0115] Meanwhile, the formula for calculating the weakening ratio of the stress performance of the tested steel bar by a single measuring point can be obtained. ;

[0116] Substituting the values, we can deduce the number of measurement points. Time reduction ratio for:

[0117] ;

[0118] ;

[0119] in: This refers to the effective bond length of the reinforcing steel. The ratio of the length of the grinding plane of a single strain gauge to the effective bond length of the tested reinforcing bar along the reinforcing bar axis;

[0120] S6.2 Calculate the maximum number of measuring points that can be arranged on a single reinforcing bar being tested. Specifically:

[0121] Let the maximum allowable weakening ratio of a single tested steel bar be... ,but:

[0122] ;

[0123] The maximum number of measurement points for:

[0124] ;

[0125] in: The maximum number of measurement points is used, and the result is rounded down during calculation. This represents the maximum allowable weakening ratio for a single tested steel bar.

[0126] S7. Arrange multiple measuring points along the axial direction of the tested reinforcing bar 2 according to steps S1 to S4, and the number of measuring points shall not exceed [number missing]. In actual construction, after multiple measuring points are arranged, concrete is poured.

[0127] S8. When strain measurement is required, connect the strain gauges at multiple measuring points to the strain measurement equipment to collect the strain signal of the steel reinforcement in real time.

[0128] In this embodiment, the diameter of the reinforcing bar being measured is... The effective bonding length is 20mm. The strain gauge is 1500mm long; the strain gauge specification is 3AA, and its length is... It is 6.8mm wide. It is 4.2mm.

[0129] A grinding wheel machine was used to grind and level the surface of the reinforcing bars. The grinding plane dimensions were as follows: The polishing depth is The percentage reduction in the stress performance of the tested steel reinforcement by a single measuring point. ≈0.01; According to the calculation, the weakening effect of this measuring point on the stress performance of the steel bars in the grinding section is almost negligible. Therefore, the strain gauge of this size is selected, and the grinding method can meet the requirements of steel bar stress measurement.

[0130] In traditional slotting methods, to ensure the adhesion of strain gauges and effective protection of epoxy resin, the slot depth is typically 2.5mm. Therefore, the traditional slotting method weakens the stress on the reinforcing steel in this section. Compared with the traditional grooving method, the present invention reduces the impact on the stress performance of the strain measurement point of the steel bar by more than 80%. While ensuring the reliability of strain measurement, it maximizes the stress performance of the steel bar, making it applicable to the strain measurement of steel bars in more complex structures and application scenarios.

[0131] In this embodiment, it is assumed that =0.05, meaning that the weakening ratio of the load-bearing performance of a single reinforcing bar by multiple measuring points should not exceed 0.05. The maximum number of measuring points for a single reinforcing bar can be calculated from this. =8, meaning that in this embodiment, a maximum of 8 measuring points can be arranged on the steel bar to achieve the goal of meeting the stress performance requirements of the steel bar while collecting strain data from multiple measuring points and obtaining the spatial distribution law of steel bar strain in real time.

[0132] The present invention also provides an electronic device corresponding to the above embodiments. The electronic device may be a processing device for a client, such as a mobile phone, a laptop, a tablet computer, a desktop computer, etc., to execute the methods of the above embodiments.

[0133] The electronic device of this embodiment includes a memory, a processor, and a computer program stored in the memory; the processor executes the computer program in the memory to implement the steps of the method described in the above embodiment.

[0134] In some implementations, the memory may be high-speed random access memory (RAM), and may also include nonvolatile memory, such as at least one disk storage.

[0135] In other implementations, the processor can be any type of general-purpose processor, such as a central processing unit (CPU) or a digital signal processor (DSP), and there is no limitation here.

[0136] The present invention also provides a readable storage medium corresponding to the above embodiments, wherein a computer program / instructions are stored thereon. When the computer program / instructions are executed by a processor, they implement the steps of the methods described in the above embodiments.

[0137] A computer-readable storage medium can be a tangible device that holds and stores instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0138] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0139] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0140] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0141] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for testing the strain of reinforcing steel bars considering the effect of local bond stress, characterized in that, Includes the following steps: S1. Obtain the steel reinforcement parameters and strain gauge specifications; S2. According to the specifications of the strain gauge, determine a grinding area on one side of the longitudinal rib on the surface of the steel bar, and grind the grinding area to form a grinding plane. S3. Attach the strain gauge to the polished surface and set a strain gauge protective layer on the outer surface of the attached strain gauge; S4. Insert the strain gauge wire into the wire protection device, and fix the wire protection device along the axis of the reinforcing bar to one side of the longitudinal rib of the reinforcing bar to complete the layout of a single measuring point; S5. Evaluation indicators for confirming the weakening effect of steel bar grinding. ; Calculate the reduction ratio of the reinforcing steel's stress performance at a single measuring point. ; S6. Calculate the maximum number of measuring points that can be placed on a single steel bar. ; S7. Arrange multiple measuring points along the axial direction of the reinforcing bar according to steps S1 to S4, and the number of measuring points shall not exceed [number missing]. ; S8. Connect the strain gauges at multiple measuring points to the strain measurement equipment to acquire the strain signal of the steel bar in real time; In S2, the dimensions of the grinding surface are required as follows: ， ； in: To grind the length of the flat surface; To grind the width of the surface; The length of the strain gauge; The width of the strain gauge; Grinding depth for: ； in: Where is the radius of the reinforcing bar. The width of the strain gauge is in mm. Evaluation indicators of the weakening effect of steel bar grinding for: ； in: This refers to the anchorage length of the steel reinforcement after grinding. This refers to the anchorage length of the reinforcing steel bar before grinding. This is the reduction factor for the steel reinforcement section. This is the weakening coefficient for the bond performance of steel bars; To take the absolute value; The reduction ratio of the stress performance of steel bars by a single measuring point yes: ； S6 specifically refers to: S6.1, The reduction ratio of the stress performance of steel bars based on a single measuring point ,calculate The reduction ratio of the stress performance of steel bars at each measuring point : ； ； in: This refers to the effective bond length of the reinforcing steel. The ratio of the length of the grinding plane of a single strain gauge to the effective bond length of the reinforcing bar along the reinforcing bar axis; S6.2 Calculate the maximum number of measuring points that can be placed on a single reinforcing bar. Specifically: Let the maximum allowable weakening ratio of a single steel bar be... ,but: ； The maximum number of measurement points for: ； in, This indicates rounding down to the nearest integer.

2. The method for testing the strain of reinforcing bars considering the effect of local bond stress according to claim 1, characterized in that, The surface of the reinforcing bar has one or at least two measuring points along one side of the longitudinal rib; The grinding plane, strain gauge, and strain gauge protective layer are arranged one-to-one to form a single measuring point; the strain gauge protective layer includes a liquid insulating adhesive layer coated on the outer surface of the strain gauge.

3. A strain testing system for reinforcing bars considering the effect of local bond stress, used to implement the testing method as described in claim 1 or 2, characterized in that, It includes one or at least two measuring points arranged along the axial direction of the reinforcing bar (2) on the reinforcing bar (2); a single measuring point includes a grinding surface (5), a strain gauge (6) and a strain gauge protective layer (7) arranged sequentially on the reinforcing bar (2); the surface of the reinforcing bar (2) is provided with a grinding surface (5) formed by grinding along one side of the longitudinal rib; the strain gauge (6) is fixed to the grinding surface (5) by an adhesive layer; the strain gauge protective layer (7) is provided on the outer surface of the strain gauge (6).

4. The steel reinforcement strain testing system considering local bond stress effect according to claim 3, characterized in that, It also includes a conductor protection device (3), which is sleeved on the outside of the strain gauge conductor (4) and arranged along the axial direction of the reinforcing bar (2) and fixed to one side of its longitudinal rib; The conductor protection device (3) includes a capillary stainless steel tube; the outer diameter of the capillary stainless steel tube is not greater than the diameter of the reinforcing bar. 10% of the thickness, but not less than 1.5mm, if 10% If ≤ 1.5mm, then take 1.5mm.

5. The steel reinforcement strain testing system considering local bond stress effect according to claim 3, characterized in that, The strain gauge protective layer (7) includes at least two layers of cured liquid insulating adhesive.

6. An electronic device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program; the processor executes the computer program to implement the steel bar strain testing method considering the local bond stress effect as described in claim 1 or 2.

7. A readable storage medium, characterized in that, The readable storage medium stores a computer program, which is executed by a processor to implement the steel bar strain testing method considering local bond stress effects as described in claim 1 or 2.

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