Method, apparatus, device and storage medium for obtaining performance curve of fully-graded concrete

Abstract

The present application relates to the technical field of performance testing of fully graded concrete, and provides a method, device, equipment and storage medium for obtaining the performance curve of fully graded concrete. The method includes: based on the stress state of the fully graded concrete to be tested, designing the structures of the fully graded concrete specimen and the connecting device, and respectively conducting uniaxial tensile tests and uniaxial compression tests to obtain the corresponding displacement amounts and load peaks; respectively performing linear interpolation based on the displacement amounts and load peaks to obtain a plurality of tensile-compression conversion points and compression-tensile conversion points; adjusting the tensile load of the specimen at each tensile-compression conversion point based on the tensile loading rate, and adjusting the compressive load of the specimen at each compression-tensile conversion point based on the compressive loading rate; collecting the first deformation amount corresponding to the tensile load and the second deformation amount corresponding to the compressive load, and performing fitting to obtain the performance curve of the fully graded concrete, which can truly reflect the change law of the tensile-compression conversion elastic modulus of the dam concrete under the action of seismic cyclic loads and the whole process of concrete damage.

Description

Technical Field

[0001] The present application relates to the technical field of performance testing of full-graded concrete, and particularly to a method, device, equipment and storage medium for obtaining the performance curve of full-graded concrete. Background Art

[0002] Concrete dams are widely distributed worldwide, with a large number and generally high dam heights. They play an important role in ensuring flood control safety, water supply safety, food security, energy security and ecological security. Once a high-reservoir dam made of full-graded concrete collapses due to a strong earthquake or other extreme situations, it will seriously threaten the lives and property safety of people downstream and cause heavy losses to the social economy. Therefore, the seismic safety assessment of concrete dams is particularly important.

[0003] In the prior art, the seismic safety assessment of concrete dams can be carried out based on full-graded concrete specimens. When using full-graded concrete specimens for performance testing, separate compression and tension tests are carried out, that is, uniaxial compression and uniaxial tension tests are respectively carried out to obtain the performance curve corresponding to the concrete dam.

[0004] However, the above method cannot simulate the tensile-compressive alternating stress characteristics of dam concrete under seismic cyclic loads. At the same time, due to the large bearing capacity of full-graded concrete specimens, the above test method may cause the sudden cracking of the downward cracks, resulting in a low authenticity of the performance curve of the concrete dam obtained. Summary of the Invention

[0005] The present application provides a method, device, equipment and storage medium for obtaining the performance curve of full-graded concrete, which is used to solve the problem of low authenticity of the performance curve of the concrete dam obtained in the prior art.

[0006] In a first aspect, the present application provides a method for obtaining the performance curve of full-graded concrete, and the method includes:

[0007] Based on the stress state of the full-graded concrete to be tested, design the structures of the full-graded concrete specimen, the connecting device and the axial extensometer, and use the designed full-graded concrete specimen, connecting device and axial extensometer to respectively carry out uniaxial tension tests and uniaxial compression tests to obtain the displacement of the axial extensometer corresponding to the first load peak value and the second load peak value;

[0008] Based on the displacement and the second load peak value, respectively perform linear interpolation to obtain a plurality of tension-compression conversion points and compression-tension conversion points; the tension-compression conversion point is the critical point at which the set tension is converted into pressure; the compression-tension conversion point is the critical point at which the set pressure is converted into tension;

[0009] Obtain the tensile loading rate and the compressive loading rate, adjust the tensile load applied to the fully graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load applied to the fully graded concrete specimen at each compression-tension conversion point based on the compressive loading rate;

[0010] Collect the first deformation corresponding to the tensile load and the second deformation corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation, the compressive load, and the second deformation to obtain the performance curve of the fully graded concrete.

[0011] Optionally, based on the stress state of the fully graded concrete to be measured, design the structures of the fully graded concrete specimen, the connecting device, and the axial extensometer, including:

[0012] Based on the stress state of the fully graded concrete to be measured, embed a specific number of steel bars at both ends of the fully graded concrete specimen so that the fully graded concrete specimen evenly bears the tensile load based on the connecting device; the stress state includes axial tension and axial compression; the connecting device is provided with a support member for fixing the tensile direction of the fully graded concrete specimen;

[0013] Obtain the measurement requirements inside the fully graded concrete specimen, and calculate the number and positions of the required axial extensometers based on the measurement requirements;

[0014] Set the dimensions of the middle section of the fully graded concrete specimen, and arrange the axial extensometers on the surface of the fully graded concrete specimen based on the dimensions, the number, and the positions of the axial extensometers, and pour the fully graded concrete specimen to form a fully graded concrete specimen containing axial extensometers.

[0015] Optionally, use the designed fully graded concrete specimen, connecting device, and axial extensometer to conduct uniaxial tensile tests and uniaxial compressive tests respectively to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak, including:

[0016] Connect the designed fully graded concrete specimen and the connecting device so that the connecting device can stretch and compress the fully graded concrete specimen;

[0017] Set the tensile load of the connecting device, and stretch the fully graded concrete specimen based on the tensile load until the fully graded concrete specimen is cracked, and obtain the maximum value of the first load peak corresponding to the cracking of the fully graded concrete specimen and the value of the axial extensometer at the first load peak to obtain the displacement of the axial extensometer corresponding to the first load peak;

[0018] Set the compression load of the connection device, compress the fully graded concrete specimen based on the compression load until the fully graded concrete specimen is fractured, obtain the maximum load corresponding to the time when the fully graded concrete specimen is fractured, and obtain the second load peak value.

[0019] Optionally, perform linear interpolation based on the displacement amount and the second load peak value respectively to obtain multiple tension-compression conversion points and compression-tension conversion points, including:

[0020] For each tensile period corresponding to the tension of the fully graded concrete specimen, set the distance interval corresponding to the tension-compression conversion point, and perform linear interpolation based on the distance interval and the displacement amount to obtain multiple tension-compression conversion points; the tensile periods include: the initial stage of tension, the initial stage of tensile damage, the middle stage of tensile damage, and the late stage of tensile damage;

[0021] For each compression period corresponding to the compression of the fully graded concrete specimen, set the force interval corresponding to the compression-tension conversion point, and perform linear interpolation based on the force interval and the second load peak value to obtain multiple compression-tension conversion points; the compression periods include: the initial stage of compression, the initial stage of compression failure, the middle stage of compression failure, and the late stage of compression failure.

[0022] Optionally, for each tensile period corresponding to the tension of the fully graded concrete specimen, set the distance interval corresponding to the tension-compression conversion point, including:

[0023] For the initial stage of tension, obtain the ultimate tensile strain corresponding to the fully graded concrete specimen, and set the first distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the ultimate tensile strain;

[0024] For the initial stage of tensile damage, set the second distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the first distance interval;

[0025] For the middle stage of tensile damage, set the third distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the second distance interval;

[0026] For the late stage of tensile damage, set the fourth distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the third distance interval.

[0027] Optionally, adjust the tensile load on the fully graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compression load on the fully graded concrete specimen at each compression-tension conversion point based on the compression loading rate, including:

[0028] Adjust the tensile load corresponding to the fully-graded concrete specimen based on the tensile loading rate. After the tensile load reaches the load value corresponding to the tensile-compressive conversion point, adjust the tensile load corresponding to the fully-graded concrete specimen in the reverse direction using the unloading rate until the tensile load equals 0; the unloading rate is greater than the tensile loading rate.

[0029] After the tensile load equals 0, adjust the compressive load corresponding to the fully-graded concrete specimen based on the compressive loading rate until the compressive load reaches the load value corresponding to the compressive-tensile conversion point.

[0030] Optionally, fit the tensile load, the first deformation amount, the compressive load, and the second deformation amount to obtain a fully-graded concrete performance curve, including:

[0031] For the tensile load, the first deformation amount, the compressive load, and the second deformation amount corresponding to each time point within a preset time period, use the least squares method for fitting to obtain a fully-graded concrete performance curve.

[0032] In a second aspect, the present application also provides a device for obtaining a fully-graded concrete performance curve, the device including:

[0033] A test module, configured to design the structures of a fully-graded concrete specimen, a connection device, and an axial extensometer based on the stress state of the fully-graded concrete to be tested, and respectively conduct a uniaxial tensile test and a uniaxial compressive test using the designed fully-graded concrete specimen, connection device, and axial extensometer to obtain the displacement amount corresponding to the axial extensometer at the first load peak and the second load peak;

[0034] A calculation module, configured to respectively perform linear interpolation based on the displacement amount and the second load peak to obtain a plurality of tensile-compressive conversion points and compressive-tensile conversion points; the tensile-compressive conversion point is the critical point at which the set tensile force is converted into compressive force; the compressive-tensile conversion point is the critical point at which the set compressive force is converted into tensile force;

[0035] An adjustment module, configured to obtain the tensile loading rate and the compressive loading rate, adjust the tensile load received by the fully-graded concrete specimen at each tensile-compressive conversion point based on the tensile loading rate, and adjust the compressive load received by the fully-graded concrete specimen at each compressive-tensile conversion point based on the compressive loading rate;

[0036] A fitting module, configured to collect the first deformation amount corresponding to the tensile load and the second deformation amount corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation amount, the compressive load, and the second deformation amount to obtain a fully-graded concrete performance curve.

[0037] In a third aspect, the present application further provides an electronic device, including: a processor, and a memory communicatively connected to the processor;

[0038] The memory stores computer-executable instructions;

[0039] The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of the first aspects.

[0040] In a fourth aspect, the present application further provides a computer-readable storage medium storing computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the method according to any one of the first aspects.

[0041] In summary, the present application provides a method, device, equipment, and storage medium for obtaining the performance curve of fully graded concrete. Based on the stress state of the fully graded concrete to be tested, the structures of the fully graded concrete specimen, the connecting device, and the axial extensometer can be designed. The uniaxial tensile test and the uniaxial compression test are respectively carried out using the designed fully graded concrete specimen, the connecting device, and the axial extensometer to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak. Further, linear interpolation is respectively performed based on the displacement and the second load peak to obtain multiple tension-compression conversion points and compression-tension conversion points. Further, the tensile loading rate and the compressive loading rate are obtained, and then the tensile load applied to the fully graded concrete specimen at each tension-compression conversion point is adjusted based on the tensile loading rate, and the compressive load applied to the fully graded concrete specimen at each compression-tension conversion point is adjusted based on the compressive loading rate. Further, the first deformation amount corresponding to the tensile load and the second deformation amount corresponding to the compressive load within a preset time period are collected, and the tensile load, the first deformation amount, the compressive load, and the second deformation amount are fitted to obtain the performance curve of the fully graded concrete. Among them, the tension-compression conversion point is the critical point where the set tension is converted into pressure; the compression-tension conversion point is the critical point where the set pressure is converted into tension. In this way, by simulating the tension-compression alternating stress characteristics of dam concrete under seismic cyclic loads, the damage process of dam concrete under seismic reciprocating loads is truly reflected, and the performance curve of fully graded concrete under cyclic loads obtained is of great significance for studying the true performance of fully graded dam concrete under seismic loads. Description of the Drawings

[0042] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0043] Figure 1 It is a schematic diagram of an application scenario provided by an embodiment of the present application;

[0044] Figure 2Schematic flowchart of a method for obtaining the performance curve of fully graded concrete provided by an embodiment of the present application;

[0045] Figure 3 Schematic structural diagram of a fully graded concrete specimen provided by an embodiment of the present application;

[0046] Figure 4 Schematic structural diagram of the position of steel bars in a fully graded concrete specimen provided by an embodiment of the present application;

[0047] Figure 5 Schematic structural diagram of a connecting device for a fully graded concrete specimen provided by an embodiment of the present application;

[0048] Figure 6 Schematic flowchart of a specific process for obtaining the performance curve of fully graded concrete provided by an embodiment of the present application;

[0049] Figure 7 Schematic structural diagram of a device for obtaining the performance curve of fully graded concrete provided by an embodiment of the present application;

[0050] Figure 8 Schematic structural diagram of an electronic device provided by an embodiment of the present application.

[0051] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed Description of Specific Embodiments

[0052] Here, exemplary embodiments will be described in detail, and their examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0053] In order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and roles. For example, the first device and the second device are only used to distinguish different devices, and their sequence is not limited. Those skilled in the art can understand that the terms "first" and "second" do not limit the quantity and execution order, and the terms "first" and "second" do not necessarily limit differences.

[0054] It should be noted that in this application, words such as "exemplary" or "for example" are used to give examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0055] In this application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one (item)" or its similar expression refers to any combination of these items, including any combination of single item (item) or plural items (items). For example, at least one (item) of a, b, or c can represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c can be single or multiple.

[0056] To fully develop water energy and ensure the safety of people in strong earthquake areas, high concrete dams such as 300 - m - class high concrete dams can be built in strong earthquake areas. However, once a high - reservoir dam made of mass - concrete experiences extreme situations such as dam break due to strong earthquakes, it will seriously threaten the lives and property safety of people downstream and cause significant losses to social economy. Therefore, the seismic safety assessment of 300 - m - class high concrete dams is particularly important.

[0057] In a possible implementation, the seismic safety assessment of a concrete dam can be based on mass - concrete specimens. When conducting performance tests on mass - concrete specimens, separate compression and tension tests are carried out, that is, uniaxial compression and uniaxial tension tests are respectively conducted to obtain the corresponding performance curves of the concrete dam.

[0058] However, the above - mentioned method cannot simulate the tensile - compression alternating stress characteristics of dam concrete under seismic cyclic loads. At the same time, due to the large bearing capacity of mass - concrete specimens, the above - mentioned test method may cause instantaneous cracking of the downward cracks, resulting in a relatively low authenticity of the performance curves of the concrete dam obtained.

[0059] It should be noted that the tensile - compression damage full curve of mass - concrete under seismic cyclic loads can reveal the nonlinear dynamic response of concrete under strong earthquakes, can quantitatively give the damage development process of mass - concrete, provide key basic data for the review of the ultimate seismic capacity of high dams, and play an important role in ensuring the seismic safety of dams.

[0060] Therefore, in view of the above problems and considering the role of the complete - aggregate concrete specimen's tensile - compressive damage full - curve, the present application provides a method for obtaining the performance curve of complete - aggregate concrete. By simulating the tensile - compressive alternating stress characteristics of dam concrete under seismic cyclic loads, it can truly reflect the damage process of dam concrete under seismic reciprocating loads. Specifically, this method prepares complete - aggregate concrete tensile - compressive specimens and connection devices, enabling the acquisition of tensile - compression conversion points and compression - tension conversion points. Further, by adjusting the complete - aggregate concrete specimens through the corresponding tensile - compressive control mode and tensile - compressive specimen control mode under cyclic loads, and obtaining the corresponding loads and displacements at different time intervals, and fitting them, the complete - aggregate concrete tensile - compressive damage full - curve (performance curve) can be obtained. In this way, by simulating the tensile - compressive cyclic action endured by complete - aggregate dam concrete under seismic action, the complete - aggregate concrete tensile - compressive damage full - curve under cyclic loads is obtained, which is of great significance for studying the true performance of complete - aggregate dam concrete under seismic loads.

[0061] The following introduces the embodiments of the present application with reference to the accompanying drawings. Figure 1 FIG. is a schematic diagram of an application scenario provided by an embodiment of the present application. The method for obtaining the performance curve of complete - aggregate concrete provided by the present application can be applied to an application scenario as Figure 1 shown. This application scenario includes: a complete - aggregate concrete specimen 101, a test simulation platform 102, and a user's operating device 103. Among them, the complete - aggregate concrete specimen 101 is connected with a connection device, which is used to ensure that the complete - aggregate concrete specimen is in a uniformly tensile state at the initial stage of tension and compression.

[0062] Specifically, based on the connection device, the stress condition of the complete - aggregate concrete specimen 101 is adjusted to enable the test simulation platform 102 to simulate the tensile - compressive cyclic action endured by dam concrete under seismic action. By obtaining the loads and deformations corresponding to multiple tensile - compressive alternating stress conversion points at different time intervals, and further, based on the test procedure, fitting the loads and deformations corresponding to different time intervals obtained, the complete - aggregate concrete performance curve is obtained and displayed on the user's operating device 103, so that the user can study the damage development process of complete - aggregate concrete based on the complete - aggregate concrete performance curve, and then formulate reasonable strategies to ensure the seismic safety of the dam.

[0063] The following uses specific embodiments to elaborate on the technical solutions of the present application in detail. These several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The following will describe the embodiments of the present application with reference to the accompanying drawings.

[0064] Figure 2 FIG. is a schematic flow chart of a method for obtaining the performance curve of complete - aggregate concrete provided by an embodiment of the present application, asFigure 2 As shown, the method for obtaining the performance curve of fully graded concrete includes the following steps:

[0065] S201. Based on the stress state of the fully graded concrete to be tested, design the structures of the fully graded concrete specimen, the connecting device, and the axial extensometer, and use the designed fully graded concrete specimen, connecting device, and axial extensometer to conduct uniaxial tensile tests and uniaxial compressive tests respectively to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak.

[0066] In the embodiments of the present application, fully graded concrete refers to a mixture containing four gradations in the concrete mix ratio, that is, the coarse aggregate is divided into pebbles, crushed stones, crushed pebbles, and the mixture of pebbles and crushed stones according to types, and is divided into small stones (5 - 20 mm), medium stones (20 - 40 mm), large stones (40 - 80 mm), and extra-large stones (80 - 150 mm) according to particle sizes, which are successively called the first, second, third, and fourth gradations.

[0067] The uniaxial tensile test may refer to a test method in which a steel plate of a certain thickness is pasted at each end of a prismatic or cylindrical concrete specimen, and then a load is applied along the central axis; the uniaxial compressive test may refer to an in-situ test method for measuring the deformation index of uniaxial or biaxial rock masses. Four mutually perpendicular slots can be cut in the rock mass, and steel pillows are respectively or simultaneously buried in the two pairs of opposite slots, and the rock mass is pressurized through the steel pillows to measure the deformation value of the rock mass, and the deformation modulus is calculated according to the unidirectional or bidirectional compression formula of elastic mechanics.

[0068] In this step, based on the stress state of the fully graded concrete to be tested, the preparation requirements for the fully graded concrete tensile-compression specimen (fully graded concrete specimen), the preparation requirements for the fully graded concrete tensile-compression connecting device, and the layout method and requirements of the axial extensometer can be designed. Further, based on the preparation requirements and the layout method and requirements of the axial extensometer, the structures of the fully graded concrete specimen, the connecting device, and the axial extensometer are designed so that the fully graded concrete specimen can withstand the tensile-compression cyclic load, and based on the connecting device, it can withstand both axial tension and axial pressure, thereby ensuring that the fully graded concrete specimen can be in a uniform tensile state.

[0069] Further, based on the uniaxial tensile test of the fully graded concrete specimen, obtain the displacement of the axial extensometer corresponding to the first load peak. The first load peak is the maximum value of the tensile force received by the fully graded concrete specimen, corresponding to the load value when it is about to be cracked; and based on the uniaxial compressive test of the fully graded concrete specimen, obtain the second load peak. The second load peak is the maximum value of the compressive force received by the fully graded concrete specimen, corresponding to the load value when it is about to be compressed and damaged.

[0070] S202. Perform linear interpolation based on the displacement and the second load peak respectively to obtain a plurality of tension-compression conversion points and compression-tension conversion points. The tension-compression conversion point is the critical point where the set tension is converted into pressure, and the compression-tension conversion point is the critical point where the set pressure is converted into tension.

[0071] In this step, linear interpolation can be performed between zero and the displacement corresponding to the first load peak. The displacement is the maximum value of the axial extensometer corresponding to the first load peak measured by the axial extensometer, that is, a plurality of tension-compression conversion points are selected between zero and the displacement corresponding to the first load peak based on a preset step size. The tension-compression conversion points are predefined. Similarly, linear interpolation can be performed between zero and the second load peak to obtain a plurality of compression-tension conversion points.

[0072] It should be noted that due to the discreteness of the fully graded concrete specimens, the ultimate compressive load is an unknown quantity. Therefore, the method of specifying the percentage reduction of the load is adopted as the setting method for the compression-tension conversion points of the fully graded concrete specimens, that is, the load is compared with the maximum load number in the historical record in real time, and the compression-tension conversion points are selected in turn until the load is reduced to the specified percentage of the maximum load in the historical record.

[0073] S203. Obtain the tensile loading rate and the compressive loading rate, and adjust the tensile load on the fully graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load on the fully graded concrete specimen at each compression-tension conversion point based on the compressive loading rate.

[0074] In the embodiments of the present application, the tensile loading rate may refer to the operating speed corresponding to the tensile deformation of the fully graded concrete specimen, which is used to change the tensile force on the fully graded concrete specimen. The compressive loading rate may refer to the operating speed corresponding to the compressive deformation of the fully graded concrete specimen, which is used to change the compressive force on the fully graded concrete specimen. The specific values corresponding to the tensile loading rate and the compressive loading rate are not limited in the embodiments of the present application.

[0075] In this step, adjust the tensile load on the fully graded concrete specimen at each tension-compression conversion point and the compressive load on the fully graded concrete specimen at each compression-tension conversion point based on the tension-compression control mode of the fully graded concrete specimen under cyclic loading, that is, use the tensile loading rate to make the fully graded concrete specimen start to be tensioned. When the fully graded concrete specimen reaches each tension-compression conversion point, first quickly reduce the tensile load on the fully graded concrete specimen to 0, and then use the compressive loading rate to make the fully graded concrete specimen start to be compressed until the compression-tension conversion point is reached. Among them, the corresponding positions and load magnitudes of the fully graded concrete specimen at the tension-compression conversion point and the compression-tension conversion point need to be recorded.

[0076] S204. Collect the first deformation corresponding to the tensile load and the second deformation corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation, the compressive load, and the second deformation to obtain the performance curve of the full-graded concrete.

[0077] In the embodiment of the present application, the preset time period may refer to the time period set for collecting the required amount of data. Since the cycle load acting on the full-graded concrete tensile-compressive damage test cycle is relatively long, if the data is collected at equal time intervals, the amount of data will be very large, and it cannot simultaneously meet the high sampling rate required at the moment of tensile failure and the lower sampling rate required in the quasi-static state. Therefore, the present application adopts a sampling method with equal load intervals, that is, the load and the deformation are collected at equal load intervals within the preset time period.

[0078] In this step, based on the test process of the full-graded concrete tensile-compressive damage full curve, the performance curve of the full-graded concrete is obtained, and the test process is designed and implemented based on the test program under cyclic load.

[0079] Therefore, the embodiment of the present application provides a method for obtaining the performance curve of full-graded concrete. The structure of the full-graded concrete specimen, the connecting device, and the axial extensometer can be designed based on the stress state of the full-graded concrete to be tested, and the uniaxial tensile test and the uniaxial compression test are respectively carried out using the designed full-graded concrete specimen, the connecting device, and the axial extensometer to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak; further, linear interpolation is respectively performed based on the displacement and the second load peak to obtain multiple tensile-compressive conversion points and compressive-tensile conversion points; further, the tensile loading rate and the compressive loading rate are obtained, and then the tensile load applied to the full-graded concrete specimen at each tensile-compressive conversion point is adjusted based on the tensile loading rate, and the compressive load applied to the full-graded concrete specimen at each compressive-tensile conversion point is adjusted based on the compressive loading rate; further, the first deformation corresponding to the tensile load and the second deformation corresponding to the compressive load within a preset time period are collected, and the tensile load, the first deformation, the compressive load, and the second deformation are fitted to obtain the performance curve of the full-graded concrete. In this way, by simulating the tensile-compressive alternating stress characteristics of the dam concrete under seismic cyclic load, the damage process of the dam concrete under seismic reciprocating load is truly reflected, and the performance curve of the full-graded concrete under cyclic load obtained is of great significance for studying the true performance of the full-graded dam concrete under seismic load.

[0080] Optionally, designing the structure of the full-graded concrete specimen, the connecting device, and the axial extensometer based on the stress state of the full-graded concrete to be tested includes:

[0081] Based on the stress state of the full-graded concrete to be tested, a specific number of steel bars are embedded at both ends of the full-graded concrete specimen so that the full-graded concrete specimen uniformly bears tensile loads based on the connecting device; the stress state includes axial tension and axial pressure; the connecting device is provided with a support member for fixing the tensile direction of the full-graded concrete specimen;

[0082] Obtain the measurement requirements inside the full-graded concrete specimen, and calculate the number and positions of the required axial extensometers based on the measurement requirements;

[0083] Set the dimensions of the middle section of the full-graded concrete specimen, and arrange the axial extensometers on the surface of the full-graded concrete specimen based on the dimensions, the number and positions of the axial extensometers, and pour the full-graded concrete specimen to form a full-graded concrete specimen containing axial extensometers.

[0084] In the embodiments of the present application, the specific number is the number of steel bars designed for the full-graded concrete specimen to bear tensile loads. Preferably, the specific number is 8. Figure 3 This is a schematic structural diagram of a full-graded concrete specimen provided by an embodiment of the present application, as Figure 3 shown. 8 steel bars are embedded at both ends of the prepared full-graded concrete specimen so that it can bear tensile loads. At the same time, the middle section of the full-graded concrete specimen is cast with full-graded concrete, and the length of the pure tension section in the middle is not less than 450 mm, such as 500 mm, to ensure that the middle section of the full-graded concrete specimen is in a uniform stress state during the initial stage of tension.

[0085] Among them, the specific dimensions of the 8 steel bars are as Figure 4 shown. Figure 4 This is a schematic structural diagram of the positions of steel bars in a full-graded concrete specimen provided by an embodiment of the present application, as Figure 4 shown. The 8 steel bars are divided into 4 outer-circle inserted bars and 4 inner-circle inserted bars. Among them, the interval between every two of the 4 outer-circle inserted bars is 244.8 mm, and the interval between every two of the 4 inner-circle inserted bars is 225 mm. The corresponding length of the 4 outer-circle inserted bars is 400 mm, including 335 mm embedded and 65 mm exposed. The corresponding length of the 4 inner-circle inserted bars is 350 mm, including 285 mm embedded and 65 mm exposed. The bottom end of the inserted bar is 85 mm long. The diameter of the embedded inserted bar is 36 mm, and the diameter of the exposed inserted bar (helical-thread inserted bar) is 24 mm.

[0086] It should be noted that the full-graded concrete specimen designed in the embodiments of the present application can ensure that the full-graded concrete specimen is in a uniform tension state during the initial stage of tension and compression, which requires the assistance of the connecting device of the full-graded concrete specimen. Figure 5Schematic diagram of the structure of a connection device for a fully graded concrete specimen provided by an embodiment of the present application; as Figure 5 shown, Figure 5 The connection device shown as A in [the figure] is an existing connection device. This connection device cannot ensure that the fully graded concrete specimen is in a uniform state during tension, is prone to force deviation, and large cracks are generated. However, the connection device designed in the present application is as shown in Figure 5 B in [the figure], and is provided with a support member 501, which can fix the tension direction of the fully graded concrete specimen, so that it can not only withstand axial tensile forces of dozens of tons, but also withstand axial compressive forces of more than a thousand tons, and maintain the balance of the tensile state.

[0087] In this step, the end face of the steel bar of the fully graded concrete specimen should be slightly lower than the concrete bearing surface to ensure that the end of the fully graded concrete specimen can not only transfer the tensile load, but also evenly bear the compressive load. Further, after the designed fully graded concrete specimen and the connection device can withstand the tensile-compressive cyclic load, 4 axial extensometers evenly distributed on the circumferential surface in the middle of the specimen are also required to capture the displacement corresponding to the tensile deformation of the fully graded concrete specimen in real time. Among them, the axial extensometer is located in the middle pure tensile section of the fully graded concrete specimen, and its corresponding length is not less than 450 mm.

[0088] It can be understood that 8 axial extensometers can be arranged on the circumferential surface in the middle of the specimen under conditions permitting. The more the number of arranged axial extensometers, the higher the corresponding control accuracy. The embodiment of the present application does not specifically limit the number of arranged axial extensometers. It should also be noted that the embodiment of the present application does not specifically limit the deployment position and size of the steel bars in the fully graded concrete specimen. The above is only an example for illustration.

[0089] Therefore, the embodiment of the present application designs the structures of the fully graded concrete specimen, the connection device and the axial extensometer, so that it can not only withstand the tensile load, but also meet the requirement that the middle section of the specimen is in a uniform stress state at the initial stage of tension, and improve the stability of the test.

[0090] Optionally, using the designed fully graded concrete specimen, connection device and axial extensometer to conduct uniaxial tensile tests and uniaxial compressive tests respectively, and obtaining the displacement of the axial extensometer corresponding to the first load peak and the second load peak, including:

[0091] Connect the designed fully graded concrete specimen and the connection device so that the connection device can stretch and compress the fully graded concrete specimen;

[0092] Set the tensile load of the connecting device, and perform tensile tests on the fully-graded concrete specimens based on the tensile load until the fully-graded concrete specimens are cracked. Obtain the maximum value among the first load peak corresponding to the fully-graded concrete specimens being cracked and the value corresponding to the axial extensometer at the first load peak, and obtain the displacement of the axial extensometer corresponding to the first load peak.

[0093] Set the compressive load of the connecting device, and perform compression tests on the fully-graded concrete specimens based on the compressive load until the fully-graded concrete specimens are cracked. Obtain the maximum load corresponding to the fully-graded concrete specimens being cracked, and obtain the second load peak.

[0094] In this step, the setting of the tension-compression conversion point is obtained based on the uniaxial tensile test of the fully-graded concrete specimens, that is, perform tensile tests on the fully-graded concrete specimens based on the tensile load, and obtain the maximum value among the axial extensometer values corresponding to the load peak when all axial extensometers are cracked in the fully-graded concrete specimens, which is the displacement of the axial extensometer corresponding to the first load peak. The first load peak can be obtained through a tension sensor, and the displacement is used as the judgment basis for the key point of the test tension-compression conversion; the second load peak can be obtained through a pressure sensor, which is the maximum load corresponding to the fully-graded concrete specimens being cracked.

[0095] Therefore, in the embodiments of the present application, by capturing the maximum value of the tensile deformation of the fully-graded concrete specimens as the judgment basis for the key point of the test tension-compression conversion, the accuracy of the test can be improved, so that the tensile force and the pressure will not exceed the maximum value, and the damage of the fully-graded concrete specimens can be reduced.

[0096] Optionally, perform linear interpolation based on the displacement and the second load peak respectively to obtain multiple tension-compression conversion points and compression-tension conversion points, including:

[0097] For each tensile period corresponding to the tensile test of the fully-graded concrete specimens, set the distance interval corresponding to the tension-compression conversion point, and perform linear interpolation based on the distance interval and the displacement to obtain multiple tension-compression conversion points; the tensile periods include: the initial tensile stage, the initial tensile damage stage, the middle tensile damage stage, and the late tensile damage stage.

[0098] For each compressive period corresponding to the compression test of the fully-graded concrete specimens, set the force interval corresponding to the compression-tension conversion point, and perform linear interpolation based on the force interval and the second load peak to obtain multiple compression-tension conversion points; the compressive periods include: the initial compression stage, the initial compression failure stage, the middle compression failure stage, and the late compression failure stage.

[0099] In the embodiments of the present application, the tension period includes: the initial tension period, the initial tension damage period, the middle tension damage period, and the late tension damage period. Among them, the initial tension period may refer to the linear elastic stage corresponding to the fully graded concrete specimen; the initial tension damage period may refer to the stage of crack appearance and rapid development of the fully graded concrete specimen, that is, the period corresponding to the imminent crack appearance of the fully graded concrete specimen; the middle tension damage period may refer to the stage of relatively stable crack development after the peak value of the ultimate load of the fully graded concrete specimen, that is, a certain stable development period corresponding to the crack appearance of the fully graded concrete specimen; the late tension damage period may refer to the tension damage stage of the fully graded concrete specimen, in which the load-bearing tensile capacity of the specimen is low, but the crack develops rapidly.

[0100] Since each specimen has differences, the degree of change in the deformation of the fully graded concrete specimen is different at different stages, so the distance intervals for selecting the tension-compression conversion points are also different. For example, in the linear elastic stage, the interval of the tension-compression conversion point can be taken as 10 με.

[0101] It should be noted that in order to coordinate with the tension-compression conversion point, the compression period corresponding to the compression-tension conversion point corresponds to the tension period. Since the compression failure of the fully graded concrete specimen does not occur earlier than the tension failure, the selection of the force interval can refer to the selection of the distance interval, but appropriate adjustments can be made based on the actual situation. The embodiments of the present application do not make specific limitations on this.

[0102] In this step, different tension periods correspond to different load peak values, displacement amounts, and distance intervals. That is, linear interpolation can be performed between zero and the maximum value of the axial extensometer corresponding to the given load peak value based on different distance intervals to obtain multiple tension-compression conversion points. Correspondingly, different compression periods correspond to different load peak values and force intervals. That is, linear interpolation can be performed between zero and the given load peak value based on different force intervals to obtain multiple compression-tension conversion points.

[0103] It should be noted that due to the large deformation of the fully graded concrete specimen during compression failure, the compression-tension conversion point can adopt the given load method. For example, in the elastic stage, when selecting the compression-tension conversion point, the load peak value obtained from the uniaxial compression test of the fully graded concrete specimen can be referred to. It is recommended to perform linear interpolation between 0-60% of the estimated load peak value to obtain multiple compression-tension conversion points.

[0104] Therefore, the embodiments of the present application can select the key control points for tension failure and compression failure of the fully graded concrete specimen based on the tension-compression control method of the fully graded concrete specimen under cyclic loading, that is, based on different intervals selected at different stages, to ensure the stability and controllability of the crack development of the fully graded concrete specimen.

[0105] Optionally, for each tensile period corresponding to the tension of the full-graded concrete specimen, a distance interval corresponding to the tension-compression conversion point is set, including:

[0106] For the initial stage of tension, obtain the ultimate tensile strain corresponding to the full-graded concrete specimen, and set the first distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the ultimate tensile strain;

[0107] For the initial stage of tensile damage, set the second distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the first distance interval;

[0108] For the middle stage of tensile damage, set the third distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the second distance interval;

[0109] For the late stage of tensile damage, set the fourth distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the third distance interval.

[0110] In the embodiments of the present application, the predefined algorithm may refer to a preferred algorithm designed to meet the tensile requirements of the full-graded concrete specimen at different stages. The distance interval calculated based on the predefined algorithm can meet the requirements of different compression periods and improve the processing rate.

[0111] In this step, the ultimate tensile strain at the peak of the concrete load is about 100 με. In the linear elastic stage of the full-graded concrete specimen, linear interpolation can be performed between 0 and 60 με. Therefore, the interval of the tension-compression conversion point can be taken as 10 με. For the 500-mm measurement interval corresponding to the full-graded concrete specimen designed in the present application, the distance interval of the tension-compression key point calculated based on the predefined algorithm is 0.005 mm.

[0112] Furthermore, the tension-compression conversion point needs to be appropriately densified in the stage of crack appearance and rapid development. Linear interpolation can be performed between 60 and 200 με, and the interval of the tension-compression conversion point can be taken as 2.5 με. For the 500-mm measurement interval corresponding to the full-graded concrete specimen designed in the present application, the deformation of the specimen in the corresponding measurement area is between 0.03 mm and 0.1 mm. Therefore, the distance interval of the tension-compression conversion point can be taken as 0.00125 mm, which can be understood as reducing the first distance interval by 1 / 4 based on the predefined algorithm.

[0113] Furthermore, the key points of tension-compression conversion also need to be appropriately densified during the relatively stable development stage of cracks. Linear interpolation can be performed between 200 - 400 με, and the interval of tension-compression conversion points can be taken as 5 με. Linear interpolation is carried out between 400 - 600 με, and the interval of tension-compression conversion points can be taken as 10 με. For the 500 mm measurement interval corresponding to the fully graded concrete specimen designed in this application, the deformation of the specimen measurement area is between 0.1 mm - 0.2 mm, and the difference interval of the key points of tension-compression conversion can be taken as 0.0025 mm. Between 0.2 mm - 0.3 mm, the distance interval can be taken as 0.005 mm, which can be understood as being obtained by expanding the second distance interval by 2 times based on a predefined algorithm.

[0114] Furthermore, in the later stage of tensile damage of the specimen, the selection of the interval of tension-compression conversion points can be appropriately increased to improve the test efficiency. Linear interpolation is carried out between 600 - 2000 με, and the interval of tension-compression conversion points can be taken as 100 με. For the 500 mm measurement interval corresponding to the fully graded concrete specimen designed in this application, the deformation of the specimen measurement area is between 0.3 mm - 1 mm, and the distance interval of its tension-compression conversion points can be taken as 0.05 mm, which can be understood as being obtained by expanding the third distance interval by 10 times based on a predefined algorithm.

[0115] Optionally, for the selection method of compression-tension conversion points, the selection method of tension-compression conversion points can be referred to and will not be elaborated here. For example, at the initial stage of compression, based on the peak load obtained from the uniaxial compression test, linear interpolation can be performed between 0 - 60% of the estimated peak load, and the interval can be taken as 50 - 100 KN, and it can be appropriately adjusted according to the test results.

[0116] It should be noted that since the ultimate compressive load of the fully graded concrete specimen is usually as high as several hundred tons, a very high elastic energy is accumulated on the material testing machine and the specimen at the initial stage of specimen compressive failure. To prevent the compression cracks from cracking uncontrollably under the action of elastic energy, the percentage reduction of the specified load for the first few (10) can be taken as 99%.

[0117] In the middle and later stages of compressive failure of the fully graded concrete specimen, as the elastic energy accumulated by the material testing machine and the load-bearing capacity of the specimen decrease, it is relatively easy to control the stable development of compression cracks. At this time, to improve the test efficiency, the percentage reduction of the load at the compression-tension conversion point can be appropriately adjusted, and the value range is between 90% - 98% of the estimated peak load at this time.

[0118] Therefore, the embodiments of this application design corresponding different distance intervals for different periods, which can improve the test efficiency.

[0119] Optionally, adjust the tensile load on the fully-graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load on the fully-graded concrete specimen at each compression-tension conversion point based on the compressive loading rate, including:

[0120] Adjust the corresponding tensile load of the fully-graded concrete specimen based on the tensile loading rate. After the tensile load reaches the load value corresponding to the tension-compression conversion point, use the unloading rate to reversely adjust the corresponding tensile load of the fully-graded concrete specimen until the tensile load is equal to 0; the unloading rate is greater than the tensile loading rate;

[0121] After the tensile load is equal to 0, adjust the corresponding compressive load of the fully-graded concrete specimen based on the compressive loading rate until the compressive load reaches the load value corresponding to the compression-tension conversion point.

[0122] In this step, use the tensile loading rate to make the fully-graded concrete specimen start to be in tension. When the fully-graded concrete specimen reaches each tension-compression conversion point, use a higher unloading rate (such as 10 mm / s) than the tensile loading rate to quickly reduce the tensile load on the specimen to 0. Then, use the given compressive loading rate to make the specimen start to be in compression until the compressive load reaches the compression-tension conversion point. After reaching the load value corresponding to the compression-tension conversion point, use the unloading rate to reversely adjust the corresponding compressive load of the fully-graded concrete specimen until the compressive load is equal to 0, that is, when the load decreases from the second load peak to the load corresponding to each compression-tension conversion point, use a higher unloading rate than the compressive loading rate to quickly reduce the compressive load on the specimen to 0. The above experimental process is repeated.

[0123] It should be noted that the unloading rate is also greater than the compressive loading rate. The specific values corresponding to the tensile loading rate, the compressive loading rate, and the unloading rate in the embodiments of the present application are not limited.

[0124] Therefore, the embodiments of the present application can capture in real time the maximum value of the concrete tensile deformation measured by the axial extensometer. When it is determined that the set value is reached, control the fully-graded concrete specimen to immediately move in the reverse direction at a rate higher than the loading rate, such as the unloading rate, so that the tensile force of the fully-graded concrete specimen quickly decreases to zero, in order to prevent the cracks from continuing to expand under the action of the elastic energy accumulated by the specimen itself and the loading system during tension, reduce the tensile cracking of the fully-graded concrete specimen in an uncontrolled state, and improve the service life of the specimen.

[0125] Optionally, fit the tensile load, the first deformation amount, the compressive load, and the second deformation amount to obtain the fully-graded concrete performance curve, including:

[0126] For the tensile load, the first deformation amount, the compressive load, and the second deformation amount corresponding to each time point within a preset time period, the least squares method is used for fitting to obtain the performance curve of the fully graded concrete.

[0127] After this step, the test data points are plotted with the deformation amount as the vertical coordinate and the load (i.e., the tensile load and the compressive load) as the horizontal coordinate, and a curve equation is fitted according to the least squares principle. Among them, by adjusting the tensile loading rate and the compressive loading rate, and adjusting the corresponding positions and load magnitudes of the tensile-compressive conversion point and the compressive-tensile conversion point corresponding to the fully graded concrete specimen, the tensile-compressive damage curve (the performance curve of the fully graded concrete) of the fully graded concrete under different strain rates and different tensile-compressive combinations (such as the axial tensile damage condition under a specific precompression load, the condition of being damaged first in tension and then in compression, the condition of damage occurring in both tension and compression, etc.) can be obtained.

[0128] Therefore, the embodiments of the present application can obtain the performance curves of the fully graded concrete under different strain rates and different tensile-compressive combinations, which are used to reflect the fluctuations of the fully graded concrete under seismic loads in different working conditions, that is, the trend. It has a wide range of applications and provides a key basis for the artificial study of the ultimate seismic resistance of high dams.

[0129] Optionally, the present application can also design a deformation detection device, which is used to be sleeved outside the fully graded concrete specimen to detect the degree of compressive failure and tensile failure of the fully graded concrete specimen, and timely discover whether the fully graded concrete specimen has any abnormalities.

[0130] Combined with the above embodiments, Figure 6 It is a schematic flow chart for obtaining a specific performance curve of the fully graded concrete provided by the embodiments of the present application. As Figure 6 shown, through the given preparation requirements for the fully graded concrete specimen and the connection device, the specimen, the connection device, and the extensometer are installed. Further, based on the settings for selecting the tensile-compressive conversion point and the compressive-tensile conversion point, the tensile-compressive conversion point and the compressive-tensile conversion point corresponding to the fully graded concrete specimen are selected. By adjusting the tensile load applied to the fully graded concrete specimen at each tensile-compressive conversion point and the compressive load applied at each compressive-tensile conversion point, and collecting the corresponding deformation amounts and load magnitudes of the fully graded concrete specimen at the tensile-compressive conversion point and the compressive-tensile conversion point, and fitting them, the above test process is designed as a test program under cyclic loads. Based on this test program, the complete tensile-compressive damage curve of the fully graded concrete can be obtained.

[0131] This method can simulate the tensile-compressive cyclic action endured by the fully graded concrete of the dam under seismic action, obtain the complete tensile-compressive damage curve of the fully graded concrete under cyclic loads, and is of great significance for studying the true performance of the fully graded concrete of the dam under seismic loads.

[0132] In the foregoing embodiments, a method for obtaining the performance curve of fully graded concrete provided by the embodiments of the present application was introduced. In order to implement the various functions in the method provided by the embodiments of the present application, an electronic device as an execution subject may include a hardware structure and / or a software module, and implement the above various functions in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. Whether a certain function among the above various functions is executed in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module depends on the specific application and design constraints of the technical solution.

[0133] For example, Figure 7 FIG. is a schematic structural diagram of a device for obtaining the performance curve of fully graded concrete provided by an embodiment of the present application. As Figure 7 shown, the device includes: a test module 710, a calculation module 720, an adjustment module 730, and a fitting module 740; wherein, the test module 710 is configured to design the structures of a fully graded concrete specimen, a connecting device, and an axial extensometer based on the stress state of the fully graded concrete to be tested, and respectively conduct a uniaxial tensile test and a uniaxial compressive test using the designed fully graded concrete specimen, connecting device, and axial extensometer, and obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak.

[0134] The calculation module 720 is configured to respectively perform linear interpolation based on the displacement and the second load peak to obtain a plurality of tension-compression conversion points and compression-tension conversion points; the tension-compression conversion point is the critical point at which the set tension is converted into pressure; the compression-tension conversion point is the critical point at which the set pressure is converted into tension.

[0135] The adjustment module 730 is configured to obtain the tensile loading rate and the compressive loading rate, adjust the tensile load on the fully graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load on the fully graded concrete specimen at each compression-tension conversion point based on the compressive loading rate.

[0136] The fitting module 740 is configured to collect the first deformation amount corresponding to the tensile load and the second deformation amount corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation amount, the compressive load, and the second deformation amount to obtain the performance curve of the fully graded concrete.

[0137] Optionally, the test module 710 includes a design unit and a test unit; the design unit is configured to:

[0138] Based on the stress state of the full-graded concrete to be tested, a specific number of steel bars are embedded at both ends of the full-graded concrete specimen, so that the full-graded concrete specimen uniformly bears tensile loads based on the connecting device; the stress state includes axial tension and axial pressure; the connecting device is provided with a support member for fixing the tensile direction of the full-graded concrete specimen;

[0139] Obtain the measurement requirements inside the full-graded concrete specimen, and calculate the number and positions of the required axial extensometers based on the measurement requirements;

[0140] Set the dimensions of the middle section of the full-graded concrete specimen, and arrange the axial extensometers on the surface of the full-graded concrete specimen based on the dimensions, the number and positions of the axial extensometers, and pour the full-graded concrete specimen to form a full-graded concrete specimen containing axial extensometers.

[0141] Optionally, the test unit is used for:

[0142] Connect the designed full-graded concrete specimen and the connecting device, so that the connecting device performs tension and compression on the full-graded concrete specimen;

[0143] Set the tensile load of the connecting device, and perform tension on the full-graded concrete specimen based on the tensile load until the full-graded concrete specimen is cracked, obtain the first load peak corresponding to when the full-graded concrete specimen is cracked and the maximum value among the values corresponding to the axial extensometers at the first load peak, and obtain the displacement amount of the axial extensometer corresponding to the first load peak;

[0144] Set the compression load of the connecting device, and perform compression on the full-graded concrete specimen based on the compression load until the full-graded concrete specimen is cracked, and obtain the maximum load corresponding to when the full-graded concrete specimen is cracked to obtain the second load peak.

[0145] Optionally, the calculation module 720 includes a first setting unit and a second setting unit;

[0146] Specifically, the first setting unit is used to set the distance interval corresponding to the tension-compression conversion point for each tensile period corresponding to the tension of the full-graded concrete specimen, and perform linear interpolation based on the distance interval and the displacement amount to obtain multiple tension-compression conversion points; the tensile periods include: the initial tensile stage, the initial tensile damage stage, the middle tensile damage stage, and the late tensile damage stage;

[0147] A second setting unit, configured to set a force interval corresponding to the compression-tension conversion point for each compression period corresponding to the full-graded concrete specimen, and perform linear interpolation based on the force interval and the second load peak value to obtain a plurality of compression-tension conversion points; the compression periods include: the initial compression period, the initial compression failure period, the mid-compression failure period, and the late compression failure period.

[0148] Optionally, the first setting unit is specifically configured to:

[0149] For the initial tension period, obtain the ultimate tensile strain corresponding to the full-graded concrete specimen, and set a first distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the ultimate tensile strain;

[0150] For the initial tension damage period, set a second distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the first distance interval;

[0151] For the mid-tension damage period, set a third distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the second distance interval;

[0152] For the late tension damage period, set a fourth distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the third distance interval.

[0153] Optionally, the adjustment module 730 is specifically configured to:

[0154] Adjust the tensile load corresponding to the full-graded concrete specimen based on the tensile loading rate. After the tensile load reaches the load value corresponding to the tension-compression conversion point, reversely adjust the tensile load corresponding to the full-graded concrete specimen using the unloading rate until the tensile load is equal to 0; the unloading rate is greater than the tensile loading rate;

[0155] After the tensile load is equal to 0, adjust the compressive load corresponding to the full-graded concrete specimen based on the compressive loading rate until the compressive load reaches the load value corresponding to the compression-tension conversion point.

[0156] Optionally, the fitting module 740 is specifically configured to:

[0157] For the tensile load, the first deformation amount, the compressive load, and the second deformation amount corresponding to each time point within a preset time period, perform fitting using the least squares method to obtain the full-graded concrete performance curve.

[0158] For the specific implementation principle and effect of the full-graded concrete performance curve acquisition device provided in the embodiments of the present application, reference may be made to the relevant descriptions and effects corresponding to the above embodiments, and details are not elaborated herein.

[0159] The embodiments of the present application also provide a schematic structural diagram of an electronic device.Figure 8 The following is a schematic structural diagram of an electronic device provided by an embodiment of the present application. As Figure 8 shown, the electronic device may include: a processor 801 and a memory 802 communicatively connected to the processor; the memory 802 stores a computer program; the processor 801 executes the computer program stored in the memory 802, so that the processor 801 executes the method described in any of the foregoing embodiments.

[0160] Wherein, the memory 802 and the processor 801 may be connected through a bus 803.

[0161] An embodiment of the present application further provides a computer-readable storage medium, which stores computer program execution instructions. When the computer execution instructions are executed by a processor, they are used to implement the method described in any of the foregoing embodiments of the present application.

[0162] An embodiment of the present application further provides a chip for running instructions. The chip is used to execute the method described in any of the foregoing embodiments executed by an electronic device.

[0163] An embodiment of the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, it can implement the method described in any of the foregoing embodiments executed by an electronic device.

[0164] In several embodiments provided by the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of devices or modules can be in electrical, mechanical or other forms.

[0165] The modules described as separate components may or may not be physically separated. The components shown as modules may or may not be physical units, that is, they may be located in one place, or they may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to implement the solution of this embodiment.

[0166] In addition, in each embodiment of the present application, the functional modules can be integrated into a processing unit, or each module can exist physically alone, or two or more modules can be integrated into one unit. The units formed by the above modules can be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0167] The integrated modules implemented in the form of software functional modules can be stored in a computer-readable storage medium. The above software functional modules are stored in a storage medium and include several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute some steps of the methods described in each embodiment of the present application.

[0168] It should be understood that the above processor can be a central processing unit (CPU for short), or other general-purpose processors, digital signal processors (DSP for short), application-specific integrated circuits (ASIC for short), etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in combination with the application can be directly implemented by the execution of the hardware processor, or can be implemented by the combination of the hardware and software modules in the processor.

[0169] The memory may include a high-speed random access memory (RAM for short), and may also include a non-volatile memory (NVM for short), such as at least one disk memory, and can also be a USB flash drive, a mobile hard disk, a read-only memory, a magnetic disk, or an optical disc, etc.

[0170] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, the buses in the drawings of the present application are not limited to only one bus or one type of bus.

[0171] The above storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM for short), electrically erasable programmable read-only memory (EEPROM for short), erasable programmable read-only memory (EPROM for short), programmable read-only memory (PROM for short), read-only memory (ROM for short), magnetic memory, flash memory, a magnetic disk, or an optical disk. The storage medium can be any available medium accessible by a general-purpose or special-purpose computer.

[0172] An exemplary storage medium is coupled to the processor, enabling the processor to read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an application specific integrated circuit (ASIC for short). Of course, the processor and the storage medium can also exist as discrete components in an electronic device or a master control device.

[0173] As described above, the above are only the specific implementation manners of the embodiments of the present application, but the protection scope of the embodiments of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of the present application should be covered by the protection scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for obtaining the performance curve of fully-graded concrete, characterized in that, The method includes: Based on the stress state of the full-graded concrete to be tested, design the structures of the full-graded concrete specimen, the connecting device, and the axial extensometer, and use the designed full-graded concrete specimen, connecting device, and axial extensometer to conduct uniaxial tensile tests and uniaxial compressive tests respectively, to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak; Conduct linear interpolation based on the displacement and the second load peak respectively to obtain multiple tensile-compressive conversion points and compressive-tensile conversion points; the tensile-compressive conversion point is the critical point where the set tensile force is converted into pressure; the compressive-tensile conversion point is the critical point where the set pressure is converted into tensile force; Obtain the tensile loading rate and the compressive loading rate, adjust the tensile load applied to the full-graded concrete specimen at each tensile-compressive conversion point based on the tensile loading rate, and adjust the compressive load applied to the full-graded concrete specimen at each compressive-tensile conversion point based on the compressive loading rate; Collect the first deformation corresponding to the tensile load and the second deformation corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation, the compressive load, and the second deformation to obtain the performance curve of the full-graded concrete.

2. The method according to claim 1, characterized in that, Based on the stress state of the full-graded concrete to be tested, design the structures of the full-graded concrete specimen, the connecting device, and the axial extensometer, including: Based on the stress state of the full-graded concrete to be tested, embed a specific number of steel bars at both ends of the full-graded concrete specimen, so that the full-graded concrete specimen uniformly bears the tensile load based on the connecting device; the stress state includes axial tension and axial pressure; the connecting device is provided with a support member for fixing the tensile direction of the full-graded concrete specimen; Obtain the measurement requirements inside the full-graded concrete specimen, and calculate the number and positions of the required axial extensometers based on the measurement requirements; Set the size of the middle section of the full-graded concrete specimen, arrange the axial extensometers on the surface of the full-graded concrete specimen based on the size, the number, and the positions of the axial extensometers, and pour the full-graded concrete specimen to form a full-graded concrete specimen containing axial extensometers.

3. The method according to claim 2, characterized in that, Use the designed full-graded concrete specimen, connecting device, and axial extensometer to conduct uniaxial tensile tests and uniaxial compressive tests respectively, to obtain the displacement of the axial extensometer corresponding to the first load peak and the second load peak, including: Connect the designed full-graded concrete specimen and the connecting device so that the connecting device can stretch and compress the full-graded concrete specimen; Set the tensile load of the connecting device, stretch the full-graded concrete specimen based on the tensile load until the full-graded concrete specimen is cracked, and obtain the maximum value among the first load peak corresponding to the cracking of the full-graded concrete specimen and the value corresponding to the axial extensometer at the first load peak, to obtain the displacement of the axial extensometer corresponding to the first load peak; Set the compression load of the connecting device, and compress the fully graded concrete specimen based on the compression load until the fully graded concrete specimen is fractured. Obtain the maximum load corresponding to the moment when the fully graded concrete specimen is fractured to obtain the second load peak.

4. The method according to claim 3, characterized in that, Perform linear interpolation based on the displacement and the second load peak respectively to obtain multiple tension-compression conversion points and compression-tension conversion points, including: For each tensile stage corresponding to the tension of the fully graded concrete specimen, set the distance interval corresponding to the tension-compression conversion point, and perform linear interpolation based on the distance interval and the displacement to obtain multiple tension-compression conversion points; the tensile stages include: the initial tensile stage, the initial tensile damage stage, the mid-tensile damage stage, and the late tensile damage stage; For each compression stage corresponding to the compression of the fully graded concrete specimen, set the force interval corresponding to the compression-tension conversion point, and perform linear interpolation based on the force interval and the second load peak to obtain multiple compression-tension conversion points; the compression stages include: the initial compression stage, the initial compression failure stage, the mid-compression failure stage, and the late compression failure stage.

5. The method according to claim 4, characterized in that, For each tensile stage corresponding to the tension of the fully graded concrete specimen, set the distance interval corresponding to the tension-compression conversion point, including: For the initial tensile stage, obtain the ultimate tensile strain corresponding to the fully graded concrete specimen, and set the first distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the ultimate tensile strain; For the initial tensile damage stage, set the second distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the first distance interval; For the mid-tensile damage stage, set the third distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the second distance interval; For the late tensile damage stage, set the fourth distance interval corresponding to the tension-compression conversion point based on a predefined algorithm and the third distance interval.

6. The method according to claim 1, characterized in that, Adjust the tensile load on the fully graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load on the fully graded concrete specimen at each compression-tension conversion point based on the compressive loading rate, including: Adjust the tensile load corresponding to the fully graded concrete specimen based on the tensile loading rate. After the tensile load reaches the load value corresponding to the tension-compression conversion point, use the unloading rate to reversely adjust the tensile load corresponding to the fully graded concrete specimen until the tensile load is equal to 0; the unloading rate is greater than the tensile loading rate; After the tensile load is equal to 0, adjust the compressive load corresponding to the fully graded concrete specimen based on the compressive loading rate until the compressive load reaches the load value corresponding to the compression-tension conversion point.

7. The method according to any one of claims 1-6, characterized in that, Fit the tensile load, the first deformation amount, the compressive load, and the second deformation amount to obtain the performance curve of the fully graded concrete, including: For the tensile load, the first deformation amount, the compressive load, and the second deformation amount corresponding to each time point within a preset time period, use the least squares method for fitting to obtain the performance curve of the fully graded concrete.

8. A device for obtaining the performance curve of fully-graded concrete, characterized in that, The device includes: A test module, which is used to design the structures of a fully-graded concrete specimen, a connecting device and an axial extensometer based on the stress state of the fully-graded concrete to be tested, and respectively conduct a uniaxial tension test and a uniaxial compression test by using the designed fully-graded concrete specimen, connecting device and axial extensometer, so as to obtain the displacement of the axial extensometer corresponding to the first load peak value and the second load peak value; A calculation module, which is used to respectively perform linear interpolation based on the displacement and the second load peak value to obtain a plurality of tension-compression conversion points and compression-tension conversion points; the tension-compression conversion point is the critical point at which the set tension is converted into pressure; the compression-tension conversion point is the critical point at which the set pressure is converted into tension; An adjustment module, which is used to obtain the tensile loading rate and the compressive loading rate, adjust the tensile load borne by the fully-graded concrete specimen at each tension-compression conversion point based on the tensile loading rate, and adjust the compressive load borne by the fully-graded concrete specimen at each compression-tension conversion point based on the compressive loading rate; A fitting module, which is used to collect the first deformation amount corresponding to the tensile load and the second deformation amount corresponding to the compressive load within a preset time period, and fit the tensile load, the first deformation amount, the compressive load and the second deformation amount to obtain a fully-graded concrete performance curve.

9. An electronic device, characterized in that, Comprising: A processor, and a memory communicatively connected to the processor; The memory stores computer execution instructions; The processor executes the computer execution instructions stored in the memory to implement the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the method according to any one of claims 1-7.

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