A testing method for ECC material and related device

Abstract

The present application discloses a testing method for ECC materials and related devices, and relates to the field of material testing technology. The testing method for the ECC material comprises: obtaining tensile test data of the ECC material; the tensile test data at least comprises a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; based on the tensile test data, obtaining a first eigenvalue and a second eigenvalue; based on the first eigenvalue and the second eigenvalue, obtaining a strain hardening capacity score; based on the strain hardening capacity score, determining the strain hardening capacity of the ECC material. The present application can accurately compare the strain hardening capacity of ECC materials through the testing method for ECC materials, which is conducive to selecting suitable ECC materials in various projects.

Description

Technical Field

[0001] The present application relates to the technical field of material testing, and in particular to a method for testing ECC materials and related devices thereof. Background Art

[0002] Engineered Cementitious Composites (ECC), referred to as ECC materials, are composite materials made of cement, fly ash, quartz sand, water, fiber, admixtures, etc. ECC materials overcome the shortcomings of low tensile strength and brittle tensile failure of general concrete, and have good tensile ductility similar to metal. The ultimate elongation can reach 2% to 8% and still remain unbroken. Moreover, before the ultimate failure, the crack width can be kept within the limit, so that the crack is generally below 100μm. Since ECC materials are beneficial to the durability of engineering structures, it is named flexible concrete and sustainable concrete in engineering.

[0003] At present, ECC materials are mainly used in building structures with high tensile ductility or durability, such as connecting plates in the negative bending zone of bridges, wet joints, hinged joints, bridge deck repairs, concrete in anchorage areas, and tunnel linings. However, the tensile ductility quality of ECC materials on the market varies, and the current standards and specifications for ECC materials, unlike ordinary concrete, only stipulate the test method for the ultimate elongation index of ECC materials. Therefore, it is difficult for users to choose ECC materials with stable strain hardening capabilities. For example, although a large number of fiber concretes have qualified ultimate elongation (such as 2%, 3%), this material will show the following when subjected to ultimate stretching: Figure 1 The crack width is small and wide, which is just a collection of several Griffith cracks. The schematic diagram of the crack is as follows Figure 2 As shown in the figure, (the current standard lacks an evaluation of the stretching process, and the final crack cannot be identified by the naked eye). In the application scenario of the bridge expansion joint connecting plate, it is necessary to have a material that can meet the requirements of the ultimate elongation and the stable increase of stress as the strain increases before the material fails, and the crack width does not exceed the limit, and the material presents a saturated cracking state over the entire length of the connecting plate. Here, it is defined as an ECC material with stable strain hardening ability, that is, it produces Figure 3 In the prior art, it is impossible to accurately compare the strain hardening capacity of ECC materials, which is very disadvantageous for selecting materials with stable strain hardening capacity in engineering. Summary of the invention

[0004] The purpose of the present application is to provide a testing method for ECC materials and related devices thereof, so as to solve the technical problem in the prior art that the strain hardening capacity of ECC materials cannot be accurately compared.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] In a first aspect, the present application proposes a technical solution for a method for testing an ECC material, the method for testing an ECC material comprising:

[0007] Acquire tensile test data of the ECC material; the tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value;

[0008] Based on the tensile test data, a first eigenvalue and a second eigenvalue are obtained; the first eigenvalue is at least used to characterize the magnitude of the matrix energy consumption when the ECC material first cracks; the second eigenvalue is at least used to characterize the magnitude of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum;

[0009] Obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue;

[0010] Based on the strain hardening capacity score, a strain hardening capacity of the ECC material is determined.

[0011] In a second aspect, the present application proposes a technical solution for a testing device for ECC materials, the testing device for ECC materials comprising:

[0012] A reading module, used for obtaining the tensile test data of the ECC material; the tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value;

[0013] A processing module, configured to obtain a first eigenvalue and a second eigenvalue based on the tensile test data; the first eigenvalue is at least used to characterize the magnitude of the energy consumed by the matrix when the ECC material first cracks; the second eigenvalue is at least used to characterize the magnitude of the energy consumed by the matrix when the tensile stress of the ECC material reaches a maximum;

[0014] and, obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue;

[0015] And, based on the strain hardening capacity score, determining a strain hardening capacity of the ECC material.

[0016] In a third aspect, the present application proposes a technical solution for a testing system for ECC materials, the testing system for ECC materials comprising:

[0017] A reader, used for acquiring tensile test data of the ECC material; the tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value;

[0018] The server is used to obtain a first eigenvalue and a second eigenvalue based on the tensile test data; the first eigenvalue is at least used to characterize the energy consumed by the matrix when the ECC material first cracks; the second eigenvalue is at least used to characterize the energy consumed by the matrix when the tensile stress of the ECC material reaches a maximum;

[0019] and, obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue;

[0020] And, based on the strain hardening capacity score, determining a strain hardening capacity of the ECC material.

[0021] In a fourth aspect, the present application proposes a technical solution of a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the test method of the ECC material as described in the first aspect is implemented.

[0022] Compared with the prior art, the beneficial effects of this application are:

[0023] The present application uses a testing method for ECC materials to accurately compare the strain hardening capacity of ECC materials, which is beneficial for selecting suitable ECC materials in various projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a stress-strain curve of an ECC material in the prior art;

[0025] Figure 2 A schematic diagram of a crack of an ECC material in the prior art;

[0026] Figure 3 A schematic diagram of cracks in another ECC material in the prior art;

[0027] Figure 4 A schematic diagram of a process for testing an ECC material proposed in an embodiment of the present application;

[0028] Figure 5 A schematic diagram of a tensile stress-strain curve of an ECC material proposed in an embodiment of the present application;

[0029] Figure 6A schematic diagram of a tensile stress-strain curve formed at a single crack in the ECC material proposed in the embodiment of the present application;

[0030] Figure 7 Schematic diagram of tensile stress-strain curves of multiple stable flat cracks in the ECC material proposed in the embodiment of the present application;

[0031] Figure 8 A schematic diagram of the first eigenvalue and the second eigenvalue calculation area proposed in the embodiment of the present application;

[0032] Fig. 9 for Figure 5 The intermediate stress-strain curve is decomposed into a schematic diagram of tensile stress-strain curves of multiple steady-state cracks;

[0033] Fig.10 A tensile stress-strain curve diagram of an ECC material proposed in an embodiment of the present application;

[0034] Fig.11 A tensile stress-strain curve diagram of another ECC material proposed in an embodiment of the present application;

[0035] Fig.12 A tensile stress-strain curve diagram of another ECC material proposed in an embodiment of the present application;

[0036] Fig.13 A schematic diagram of the structure of a testing device for ECC materials proposed in an embodiment of the present application;

[0037] Fig.14 This is a schematic diagram of the structure of a testing system for ECC materials proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0038] The terms "first", "second", etc. in the specification and claims of the embodiments of the present application and the above-mentioned drawings are used to distinguish similar objects (for example, the first characteristic value and the second characteristic value are respectively represented as different characteristics, and the others are similar), and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described here can be implemented in an order other than the content illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules does not have to be limited to those steps or modules clearly listed, but may include other steps or modules that are not clearly listed or inherent to these processes, methods, products or devices. The division of modules that appear in the embodiments of the present application is only a logical division. There may be other division methods when implemented in actual applications, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling between modules, and the communication connection can be electrical or other similar forms, which are not limited in the embodiments of the present application. Furthermore, the modules or sub-modules described as separate components may or may not be physically separated, may or may not be physical modules, or may be distributed in multiple circuit modules, and some or all of the modules may be selected according to actual needs to achieve the purpose of the embodiment of the present application.

[0039] In order to solve the technical problem that the strain hardening ability of ECC materials cannot be accurately compared in the prior art, this application proposes a testing method for ECC materials, specifically, Figure 4 As shown, the ECC material testing method includes steps S100 to S400.

[0040] Step S100: Acquire tensile test data of the ECC material.

[0041] It should be clear that in this embodiment, the tensile test data at least includes a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and test time values. It should be noted that in the tensile test process of the material, recording and saving the tensile stress values, the tensile strain values ​​corresponding to the tensile stress values, and the test time values ​​for subsequent reading or use are mature technologies and will not be elaborated here.

[0042] In an embodiment of the present application, any suitable method can be used to obtain the tensile test data of the ECC material. For example, the tensile test data of the ECC material that has been pre-tested and stored can be read from a memory. Alternatively, as described below, a tensile testing machine is used to obtain the tensile test data of the ECC material. It should be clear that reading from a memory or obtaining the tensile test data of the ECC material using a tensile testing machine is a mature technology and will not be elaborated here. In other words, in an embodiment of the present application, the source of the tensile test data of the ECC material is not limited.

[0043] It should be noted that in the tensile test data of the material (hereinafter referred to as test data), the tensile stress value and the tensile strain value are in a one-to-one correspondence. By mapping the tensile stress value and the corresponding tensile strain value into a two-dimensional space, with tensile stress as the ordinate and tensile strain as the abscissa, we can obtain the following: Figure 5 The tensile stress-strain curve shown (i.e. Figure 5 Curve C in Figure 1). Figure 5 The tensile stress-strain curve of an ECC material is shown. Similarly, the tensile strain value and the test time value are also in a one-to-one correspondence. By mapping the tensile strain value and the test time value to a two-dimensional space, the tensile time-strain curve can also be obtained. Since the tensile stress-strain curve and the tensile time-strain curve are both mature technologies in the tensile test process of the material, they will not be described here.

[0044] Step S200: Based on the tensile test data, obtain a first eigenvalue and a second eigenvalue.

[0045] It should be clear that in this embodiment, the first characteristic value is at least used to characterize the energy consumption of the matrix when the ECC material first cracks, and the second characteristic value is at least used to characterize the energy consumption of the matrix when the tensile stress of the ECC material reaches the maximum.

[0046] It should be noted that after cracking occurs in ECC materials, the cracks are bridged by fibers to bear the load transferred by the matrix. ECC materials usually use fibers with smaller diameters (for example, fibers with a diameter of less than 100μm, or fibers with a diameter of less than 50μm), so each square centimeter of crack section will be bridged by thousands of fibers. As the load increases, the bridging fibers partially debond and are stretched in the open cracks, and the load they bear continues to increase until more and more fibers debond, pull out, or break, and the ECC material fails (that is, reaches the maximum tensile stress value).

[0047] like Figure 6 As shown, Figure 6 Schematic diagram of the tensile stress-strain curve formed at a single crack in the ECC material. Figure 6 middle, Indicates the stress value when the flat crack reaches steady-state cracking; Indicates the strain value when the flat crack reaches steady-state cracking. Steady-state cracking means when the opening width of the flat crack expands from zero to the steady-state cracking width. After that, the width of the crack remains unchanged and the length gradually increases until the maximum stress is reached. Then, as the stress increases, cracking will occur at a new defect, thereby continuing to repeat the above steady-state cracking process until the stress required for cracking at the new defect is greater than the minimum fiber bridging stress at all cracks. Griffith cracks occur in the material at the crack with the minimum fiber bridging stress, where the crack width gradually increases and the material fails. The above is a mature material mechanics phenomenon and will not be elaborated on here. It indicates the work done by the external force on the cracking during the steady-state cracking process. Specifically, part of the work done by the external force is consumed by the matrix (also referred to as the matrix energy consumption below), and the other part is consumed by the fibers in the matrix (also referred to as the fiber energy consumption below). When , part of the energy is consumed by the bridging fibers behind the crack tip (i.e., fiber energy consumption), and the expression of this part of the energy is: .in, express Figure 6 The stress-strain function corresponding to the stress-strain curve of medium tension; Represents the first derivative function of the stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; Represents tensile strain; when the crack opening width expands from zero to the steady-state crack width When Figure 6 The red area shown in the figure is consumed by the matrix cracking process at the crack tip. Figure 6 As shown, in the embodiment of the present application, the value of the matrix energy consumption is equal to the area enclosed between the ordinate axis and the stress-strain curve (that is, Figure 6 As the crack continues to extend (the crack width remains unchanged), the matrix energy consumption reaches a maximum value, that is, Figure 6 As shown, when the stress is at its peak When , the corresponding matrix energy consumption is the largest (the value is equivalent to Figure 6 The area of ​​the oblique line area 12 shown in FIG. 1 is the area of ​​the oblique line area 12 shown in FIG. 1 ), at which time the corresponding fiber energy consumption is also the largest (the value is equivalent to Figure 6 The sum of the areas of the red and green areas shown).

[0048] It should be noted that if the number of cracks in the ECC material is to increase but the crack width remains unchanged, the ECC material should continue to crack at new defects, which requires the ultimate tensile stress at the new defect to be Less than the minimum bridging peak stress among the N cracks that have formed That is to say, the stress at the defect of ECC material with stable strain hardening ability should always satisfy the following formula:

[0049]

[0050] in, represents the ultimate tensile stress required for the formation of the jth crack in the ECC material; represents the peak bridging stress at the i-th crack in the ECC material; It means taking the minimum value in the brackets; i and j are both positive integers, i∈[1,N], and i is less than j.

[0051] It is easy to understand that the macroscopic performance is that when the external load increases to a level that exceeds the peak bridging stress that the fiber can provide at the cracked crack, When the number of defects is greater than the number of cracks, other defects that are slightly stronger than the already cracked defects will crack. In this way, when the ultimate tensile stress required to form a new crack at the new defect is always less than the minimum value of the fiber bridging peak stress at all the cracks that have already appeared, the multi-crack cracking process will continue to occur. It can be seen that the number of defects is greater than the number of cracks. This steady-state flat crack cracking process will not end until all effective defects are used up. The crack at the minimum fiber bridging peak stress (that is, The corresponding crack begins to increase in width, and the strain hardening of the ECC material ends. At this time, the tensile stress value continues to decrease with the increase of the tensile strain value until the ECC material fails.

[0052] As can be seen from the previous text, Figure 6 The figure shows the relationship between the bridging force (i.e. tensile stress value) provided by several fibers in a single crack and the crack opening width (i.e. tensile strain value). It is not difficult to understand that the superposition of the opening widths of N flat cracks is the ultimate tensile strain of the ECC material as a whole. After the stress-strain curve of each steady-state flat crack is plotted, as shown in Figure 7 As shown. Figure 7 It can be seen that the tensile stress corresponding to the i-th flat crack in the tensile stress-strain curve is Greater than the tensile stress corresponding to the i-1th flat crack Therefore, the matrix energy dissipation at the i-th flat crack is greater than the matrix energy dissipation at the i-1-th flat crack. Figure 7 The minimum fiber bridging stress at each flat crack (i.e. Figure 7 shown ) are greater than the ultimate tensile stress required by the matrix when a crack is formed at any defect (i.e. Figure 7 shown to ).

[0053] As can be seen from the foregoing, in the embodiments of the present application, the first characteristic value is at least used to characterize the energy consumption of the matrix when cracks first occur in the ECC material.

[0054] In the embodiment of the present application, the area value formed by the stress-strain curve and the ordinate axis when the first crack of the ECC material reaches a steady-state crack can be used as the first characteristic value. Figure 6 The curve shown is the stress-strain curve of the first crack of the ECC material, and the area of ​​the shaded area 11 can be used as the first eigenvalue. It should be noted that in actual operation, it is difficult to accurately obtain the stress value and strain value when a crack reaches a steady-state crack. In other words, if the area value formed by the stress-strain curve when the first crack of the ECC material reaches a steady-state crack and the ordinate axis is used as the first eigenvalue, it is difficult to obtain the first eigenvalue.

[0055] In order to easily obtain the first characteristic value, in the embodiment of the present application, the first characteristic value may be the energy value consumed when a matrix made of the same formula as the tested ECC material (without fibers) is stretched to fracture. It should be noted that if the formula of the tested ECC material is not clear, it is difficult to make a matrix with the same formula as the tested ECC material, that is, it is difficult to obtain the energy value consumed when the matrix is ​​stretched to fracture.

[0056] In order to further facilitate the acquisition of the first eigenvalue, in another embodiment of the present application, step S200, obtaining the first eigenvalue based on the tensile test data, includes steps S210 to S240.

[0057] Step S210: Acquire a first time based on the tensile test data.

[0058] It should be clear that the first time is the time when the ECC material first cracks. In an embodiment of the present application, the first time can be manually input. When testing, the time when the ECC material first cracks when observed by the naked eye is the first time. If the stretching speed is fast during the tensile test, the time when the ECC material first cracks cannot be observed by the naked eye, then the process of the ECC material tensile test can be filmed with a camera, and the first time can be manually determined based on the video or image.

[0059] In order to automatically obtain the first time, the video or image taken above can also be input into the artificial intelligence system, and the time when the ECC material first cracks (that is, the first time) can be obtained through the artificial intelligence system.

[0060] In this embodiment, the artificial intelligence system may include an image processing device and an image recognition device, and the image processing device and the image recognition device may be deployed in an integrated manner or separately. The image processing device is at least used to perform image processing based on the image to be recognized to obtain a target image. In this embodiment, the target image refers to an image in which cracks are first generated in the ECC material during the test process. The image recognition device is used to recognize the input image and obtain an image recognition result. Among them, the image processing device may be an application that performs image processing based on the image to be recognized to obtain a target image, or a server or terminal device on which an application that performs image processing based on the image to be recognized to obtain a target image is installed; the image recognition device may be an image recognition program that recognizes an image and obtains a recognition result, and the image recognition program is, for example, an image recognition model, and the image recognition device may also be a terminal device on which an image recognition model is deployed.

[0061] Specifically, it is a mature technology to identify whether there are cracks in an image based on an artificial intelligence model. For example, similar crack identification technologies are disclosed in patent documents with patent publication numbers CN113936104A and CN114331986A. It is also a mature technology to obtain the shooting time of an image based on the first appearance of a crack. For example, similar automatic time acquisition technologies are disclosed in patent documents with patent publication numbers CN118397239A and CN102542552A.

[0062] Step S220: Based on the first time value, a first strain value is obtained by a stretching time strain function.

[0063] It should be clear that in the tensile test process of ECC materials, tensile stress and tensile strain change with time sequence, that is, the test time value, tensile stress value and tensile strain value are in a one-to-one correspondence. In other words, if the test time value is determined (for example: the first time value and the second time value below), the corresponding tensile strain value can be determined; if the tensile strain value is determined, the corresponding tensile stress value can also be determined.

[0064] In this embodiment, the stretching time strain function is a fitting function obtained by fitting each test time value and the corresponding stretching strain value. It should be noted that based on two sets of one-to-one corresponding data values ​​(i.e., test time values ​​and stretching strain values), obtaining the corresponding fitting function (i.e., stretching time strain function) is also a mature technology and will not be described in detail here.

[0065] Step S230: Based on the first strain value, obtain a first stress value from a tensile stress-strain function.

[0066] In this embodiment, the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value. It should be noted that based on two sets of one-to-one corresponding data values ​​(i.e., tensile stress values ​​and tensile strain values), obtaining the corresponding fitting function (i.e., tensile stress-strain function) is also a mature technology, which will not be described here. It is easy to understand that since the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value, the curve corresponding to the tensile stress-strain function is similar to the tensile stress-strain curve. For ease of understanding, the following can be used: Figure 5 The tensile stress-strain curve shown is regarded as the curve corresponding to the tensile stress-strain function.

[0067] Step S240: obtaining a first characteristic value based on the first stress value and the first strain value.

[0068] It should be noted that the time of the first cracking of the ECC material is easy to obtain accurately, and the corresponding stress value (i.e., the first stress value) and strain value (i.e., the first strain value) of the first cracking of the ECC material are also easy to obtain. In other words, in this embodiment, the first stress value and the first strain value are used to replace the stress value and the strain value when the first crack of the ECC material reaches a steady-state cracking, so that the first characteristic value is easy to obtain.

[0069] In one embodiment of the present application, the first characteristic value may be equal to the first stress value (ie, Figure 8 shown ) and the first strain value (i.e. Figure 8 shown ). In order to obtain the strain hardening capacity score that accurately represents the strain hardening capacity of the ECC material in step S300 (see step S270 for the specific principle), in another embodiment of the present application, in step S230, based on the first stress value and the first strain value, the calculation formula for obtaining the first eigenvalue is as follows:

[0070]

[0071] in, represents the first eigenvalue (the value is equivalent to Figure 8 The green box shown area of ​​the region); represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0072] As can be seen from the foregoing, in the embodiment of the present application, the second characteristic value is at least used to characterize the size of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum. In other words, the second characteristic value can be any suitable feature that can characterize the size of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum.

[0073] In another embodiment of the present application, step S200, based on the tensile stress-strain function, obtaining a second eigenvalue, includes steps S240 to S270.

[0074] Step S240: Obtain a second time value based on the stretch test data.

[0075] In this embodiment, the second time value is the time when the tensile stress of the ECC material reaches the maximum. It should be understood that during the tensile test of the ECC material, the time when the tensile stress of the ECC material reaches the maximum can be directly obtained by the testing equipment (e.g., tensile testing machine). Since this is a mature technology, it will not be described in detail.

[0076] Step S250: Based on the second time value, obtain a second strain value by using a stretching time strain function.

[0077] In this embodiment, the stretching time strain function is as described in step S220 and will not be described in detail here.

[0078] Step S260: Based on the second strain value, obtain a second stress value from a tensile stress-strain function.

[0079] In this embodiment, the tensile stress-strain function is as described in step S230 and will not be described in detail here.

[0080] It should be clear that most of the testing equipment can directly record and store the stress value (i.e., the second stress value) and the strain value (i.e., the second strain value) when the tensile stress of the ECC material reaches the maximum. If the testing equipment can record and store the stress value and the strain value when the tensile stress of the ECC material reaches the maximum, then steps S240 to S250 may not be performed, and step S270 may be directly performed.

[0081] Step S270: obtaining a second characteristic value based on the second stress value and the second strain value.

[0082] In order to obtain the strain hardening capacity score that accurately represents the strain hardening capacity of the ECC material in step S300, in step S270, based on the second stress value and the second strain value, a calculation formula for obtaining the second eigenvalue is as follows:

[0083]

[0084] in, represents the second eigenvalue (the value is equivalent to Figure 8 The diagonal line box shown area of ​​the region); represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function is obtained in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0085] Specifically, the principle that the second eigenvalue in step S300 in this embodiment can obtain the strain hardening capacity score that accurately represents the strain hardening capacity of the ECC material is as follows:

[0086] Depend on Figure 6 It can be seen that the matrix energy consumption when a single flat crack reaches a steady-state cracking is equal to the area of ​​the shadow area 11. Based on this, the matrix energy consumption formula when a single flat crack reaches a steady-state cracking is as follows:

[0087]

[0088] in, It indicates the matrix energy consumption when a single flat crack reaches steady-state cracking; The stress at which the crack starts in a steady state; The strain representing the steady-state cracking of the crack; Represents the stress-strain function corresponding to the crack opening process; Represents the stress-strain function The first derivative function of ; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0089] Depend on Figure 6It can be seen that the matrix energy consumption when a single flat crack reaches the maximum stress is equal to the area of ​​the oblique line area 12. Based on this, the matrix energy consumption formula for a single flat crack reaching the maximum stress is as follows:

[0090]

[0091] in, It represents the matrix energy consumption when a single flat crack reaches the maximum stress; Indicates the maximum stress during the cracking process; It represents the maximum strain during the crack opening process; Represents the stress-strain function corresponding to the crack opening process; Represents the stress-strain function The first derivative function of ; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0092] It should be noted that during the stretching process of the ECC material matrix, n (n is a positive integer greater than 1) flat cracks will be formed. It is easy to understand that the matrix energy consumption (hereinafter referred to as the first total matrix energy consumption) when each crack in the entire ECC material matrix reaches the steady-state cracking is as follows:

[0093]

[0094] Where n represents the number of flat cracks; represents the stress of the steady-state cracking process corresponding to the i-th flat crack; represents the strain of the steady-state cracking process corresponding to the i-th flat crack; represents the stress-strain function corresponding to the cracking process of the i-th flat crack; Represents the stress-strain function The first derivative function of ; It means to obtain the tensile stress-strain function corresponding to the i-th flat crack in [ , ]Calculus in the tensile strain range; It represents the matrix energy consumption when the i-th flat crack reaches steady-state cracking.

[0095] The formula for the maximum matrix energy dissipation of the entire ECC material matrix (that is, the matrix energy dissipation formed by n flat cracks, hereinafter referred to as the second total matrix energy dissipation) is as follows:

[0096]

[0097] Where n represents the number of flat cracks; represents the maximum stress during the cracking process of the i-th flat crack; represents the maximum strain during the cracking process of the i-th flat crack; represents the stress-strain function corresponding to the cracking process of the i-th flat crack; Represents the stress-strain function The first derivative function of ; It means to obtain the tensile stress-strain function corresponding to the i-th flat crack in [ , ]Calculus in the tensile strain range; It represents the matrix energy consumption when the i-th flat crack reaches the maximum stress value.

[0098] When the ECC matrix is ​​inhomogeneous and the fiber mixing is uneven, the fiber bridging force has a minimum value when comparing the flat cracks. , and the matrix fracture stress at the location where the first flat crack occurs is the minimum value of the matrix fracture stress at the locations where all flat cracks occur. , when the flat crack continues to occur, the matrix fracture stress ; then at any flat crack:

[0099]

[0100]

[0101] Under ideal conditions, the ECC matrix is ​​close to homogeneous, and the fracture energy of the ECC matrix at each flat crack is the same. The fibers are evenly mixed and distributed in the matrix, and the energy consumption provided by the fiber bridging force is the same. Therefore, the ratio of the matrix energy consumption when each flat crack of the ECC material matrix reaches steady-state cracking and the matrix energy consumption when reaching the maximum stress value during the tensile process is also the same. That is, / ≈ / ≈k, i∈[1,n], r∈[1,n], i≠r. Where n represents the number of flat cracks, and n is a positive integer greater than or equal to 2; represents the matrix energy consumption when the i-th flat crack reaches the maximum stress value; represents the matrix energy consumption when the ith flat crack reaches steady-state cracking; It represents the matrix energy consumption when the rth flat crack reaches the maximum stress value; It represents the energy consumption of the matrix when the rth flat crack reaches steady-state cracking; k is a constant.

[0102] Assumptions / ≈k, then according to the composite ratio property, we can deduce:

[0103]

[0104] in, Indicates the number of flat cracks; It represents the second total matrix energy consumption of ECC material; It represents the first total matrix energy consumption of ECC material; It represents the ratio of the matrix energy consumption when the i-th flat crack reaches the maximum stress value to the matrix energy consumption when it reaches the steady-state cracking, and k is a constant.

[0105] By formula

[0106]

[0107] After transformation, we get the following formula:

[0108]

[0109] Assuming that there is no defect weaker than the nth defect before the nth crack appears, the nth defect is where the nth crack appears, so the ECC stress-strain curve can be decomposed into the functional relationship of each steady-state crack bearing stress separately, such as Fig. 9 As shown. Then The value is equivalent to Fig. 9 The sum of the areas of the middle grid lines; The value is equivalent to Fig. 9 The sum of the areas of the single oblique lines, and n is the number of cracks.

[0110] It should be noted that Approximately Fig. 9 The total area of ​​the shaded area enclosed by the stress-strain curve and the ordinate axis (that is, the sum of the area of ​​the single oblique line area minus the area of ​​the grid line area), that is, the difference between the matrix energy consumption when all cracks reach the maximum stress value and the matrix energy consumption when all cracks reach steady-state cracking. As can be seen from the previous text, this difference is smaller than the difference between the matrix energy consumption at all cracks and the matrix energy consumption at the first n-fold initial crack. Therefore, in order to represent the area of ​​the shaded part of the grid in the figure, under ideal conditions (ECC substrate is homogeneous and the fiber mixture is evenly distributed), the matrix energy consumption when n cracks reach steady-state cracking can be approximated by taking the average value. Therefore, The energy consumption of the matrix when the first crack reaches steady-state cracking can be approximated by Figure 8 The area within the green box is calculated as follows: .

[0111] That is to say, in the embodiment of the present application, if the first characteristic value is: ; The second eigenvalue is: , then a strain hardening capacity score that accurately represents the strain hardening capacity of the ECC material can be obtained in step S300.

[0112] Step S300: obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue.

[0113] In the embodiment of the present application, the strain hardening capacity score may be the difference between the second eigenvalue and the first eigenvalue. It is easy to understand that in the present embodiment, if the strain hardening capacity score is larger, it means that the strain hardening capacity of the ECC material is better.

[0114] In another embodiment of the present application, in step S300, based on the first eigenvalue and the second eigenvalue, a calculation formula for obtaining a strain hardening capacity score is as follows:

[0115]

[0116] Where D represents the strain hardening capacity fraction; represents the first eigenvalue; It is easy to understand that in this embodiment, if the strain hardening ability score is larger, it means that the strain hardening ability of the ECC material is better.

[0117] Step S400: Determine the strain hardening capacity of the ECC material based on the strain hardening capacity score.

[0118] As can be seen from the foregoing, in the embodiments of the present application, the strain hardening capacity of the ECC material can be reflected by the strain hardening capacity score.

[0119] In an embodiment of the present application, a constant k can be set according to demand to determine whether the ECC material meets the use requirements. It is easy to understand that the larger the constant k is, the stronger the strain hardening ability of the subsequently screened ECC material will be. After extensive research by the inventors, it was found that when the constant k is greater than or equal to 4, the ECC material has a stable strain hardening ability and can be applied to many application scenarios with "high stress, large deformation, and micro cracks", such as the application scenario of bridge expansion joint connecting plates. Based on this, step S400, based on the strain hardening ability score, evaluates the strain hardening ability of the ECC material, including: if the strain hardening ability score is greater than or equal to 3n, it is determined that the ECC material has a stable strain hardening ability; otherwise, it is determined that it does not have a stable strain hardening ability; n is the number of cracks generated after the tensile stress of the ECC material reaches the maximum.

[0120] Specifically, if the constant k is greater than or equal to 4, that is / ≥4; among which, represents the matrix energy dissipation of the i-th flat crack; represents the matrix energy consumption of the i-th flat crack. Based on this, the following formula is obtained:

[0121]

[0122] After transformation, we get the following formula:

[0123]

[0124] Further, Approximately the above ;Will Approximately the above , if the strain hardening capacity fraction D is greater than or equal to , then it is judged that the ECC material has stable strain hardening ability, where n is the number of cracks.

[0125] It is easy to understand that in this embodiment, if the strain hardening capacity fraction is greater than or equal to 3n, the crack state of the ECC material is likely to be as follows: Figure 3 As shown, the ECC material has a stable strain hardening ability. If the strain hardening ability score is less than 3n, the strain hardening ability of the ECC material may be unstable, or it may not be a strain hardening material at all. In this embodiment, the number of cracks generated when the tensile stress of the ECC material reaches the maximum can be obtained manually, or the number of cracks can be output by a concrete crack detector. It should be clear that outputting the number of cracks in concrete through a concrete crack detector is a mature technology and will not be described in detail here.

[0126] Specifically, in order to verify the accuracy of the test method for ECC materials proposed in this application, this application conducts experiments with three ECC materials with different strain hardening capabilities, using three specimens for each material. The tensile stress-strain curves of the tests are shown in FIG. Figures 10 to 12 As shown. Among them, Fig.10 is the tensile stress-strain curve of the ECC material with stable strain hardening ability; Fig.11 is the tensile stress-strain curve of the ECC material with unstable strain hardening ability; Fig.12 is the tensile stress-strain curve of other materials that do not have strain hardening ability. Fig.10 The tensile stress-strain curve of the strain hardening capacity fraction is 2201, and the corresponding number of cracks is 91; Fig.11 The tensile stress-strain curve of the strain hardening capacity fraction is 28, and the corresponding number of cracks is 12; Fig.12 The tensile stress-strain curve corresponds to a strain hardening capacity fraction of 0.106 and a corresponding crack number of 1.

[0127] It should be clear that the present application, through the testing method of ECC materials, can accurately compare the strain hardening capacity of ECC materials, which is conducive to selecting suitable ECC materials in various projects.

[0128] After introducing the test method of the ECC material proposed in the embodiment of the present application, the following introduces a test device of the ECC material proposed in the embodiment of the present application. Fig.13 As shown, the testing device 10 of the ECC material comprises: a reading module 11, used to obtain the tensile test data of the ECC material; the tensile test data at least comprises a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value;

[0129] The processing module 12 is used to obtain a first eigenvalue and a second eigenvalue based on the tensile test data; the first eigenvalue is at least used to characterize the amount of energy consumed by the matrix when the ECC material first cracks; the second eigenvalue is at least used to characterize the amount of energy consumed by the matrix when the tensile stress of the ECC material reaches a maximum; and, based on the first eigenvalue and the second eigenvalue, obtain a strain hardening capacity score; and, based on the strain hardening capacity score, determine the strain hardening capacity of the ECC material.

[0130] As a specific embodiment of the present application, the processing module 12 is also used to obtain a first time value based on the tensile test data; the first time value is the time value when the ECC material first generates cracks; and, based on the first time value, a first strain value is obtained from a tensile time strain function; the tensile time strain function is fitted by each tensile strain value and the corresponding test time value; and, based on the first strain value, a first stress value is obtained from a tensile stress strain function; the tensile stress strain function is fitted by each tensile stress value and the corresponding tensile strain value; and, based on the first stress value and the first strain value, a first eigenvalue is obtained.

[0131] As a specific embodiment of the present application, the processing module 12 is further used to obtain a calculation formula for a first eigenvalue based on the first stress value and the first strain value as follows:

[0132]

[0133] in, represents the first eigenvalue; represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; represents tensile strain.

[0134] As a specific embodiment of the present application, the processing module 12 is also used to obtain a second time value based on the tensile test data; the second time value is the time value when the tensile stress of the ECC material reaches a maximum; and, based on the second time value, a second strain value is obtained from a tensile time strain function; the tensile time strain function is fitted by each tensile strain value and the corresponding test time value; and, based on the second strain value, a second stress value is obtained from a tensile stress strain function; the tensile stress strain function is fitted by each tensile stress value and the corresponding tensile strain value; and, based on the second stress value and the second strain value, a second characteristic value is obtained.

[0135] As a specific embodiment of the present application, the processing module 12 is further used to obtain a calculation formula for a second characteristic value based on the second stress value and the second strain value as follows:

[0136]

[0137] in, represents the second eigenvalue; represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0138] As a specific embodiment of the present application, the processing module 12 is further used to obtain a calculation formula for the strain hardening capacity score based on the first eigenvalue and the second eigenvalue as follows:

[0139]

[0140] Where D represents the strain hardening capacity fraction; represents the first eigenvalue; represents the second eigenvalue.

[0141] As a specific embodiment of the present application, the processing module 12 is also used to determine that the ECC material has stable strain hardening ability if the strain hardening capacity score is greater than or equal to 3n; otherwise, it is determined that it does not have stable strain hardening ability; n is the number of cracks that have been generated when the tensile stress of the ECC material reaches the maximum.

[0142] It should be clear that the present application can accurately compare the strain hardening capacity of ECC materials through the testing device of ECC materials, which is conducive to selecting suitable ECC materials in various projects.

[0143] After introducing the test device of the ECC material proposed in the embodiment of the present application, the following introduces a test system of the ECC material proposed in the embodiment of the present application. Fig.14 As shown, the ECC material testing system 20 comprises: a reader 21, used to obtain the tensile test data of the ECC material; the tensile test data at least comprises a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value;

[0144] The server 22 is used to obtain a first characteristic value and a second characteristic value based on the tensile test data; the first characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the ECC material first cracks; the second characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum;

[0145] and, obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue;

[0146] And, based on the strain hardening capacity score, determining a strain hardening capacity of the ECC material.

[0147] As a specific embodiment of the present application, the server 22 is further used to obtain a first time value based on the tensile test data; the first time value is a time value when the ECC material first generates a crack; and, based on the first time value, obtain a first strain value from a tensile time strain function; the tensile time strain function is obtained by fitting each tensile strain value and the corresponding test time value;

[0148] And, based on the first strain value, a first stress value is obtained by a tensile stress-strain function; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; and, based on the first stress value and the first strain value, a first eigenvalue is obtained.

[0149] As a specific embodiment of the present application, the server 22 is further configured to obtain a calculation formula for a first characteristic value based on the first stress value and the first strain value as follows:

[0150]

[0151] in, represents the first eigenvalue; represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; represents tensile strain.

[0152] As a specific embodiment of the present application, the server 22 is also used to obtain a second time value based on the tensile test data; the second time value is the time value when the tensile stress of the ECC material reaches a maximum; and, based on the second time value, a second strain value is obtained from a tensile time strain function; the tensile time strain function is fitted by each tensile strain value and the corresponding test time value; and, based on the second strain value, a second stress value is obtained from a tensile stress strain function; the tensile stress strain function is fitted by each tensile stress value and the corresponding tensile strain value; and, based on the second stress value and the second strain value, a second characteristic value is obtained.

[0153] As a specific embodiment of the present application, the server 22 is further configured to obtain a calculation formula for a second characteristic value based on the second stress value and the second strain value as follows:

[0154]

[0155] in, represents the second eigenvalue; represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain.

[0156] As a specific embodiment of the present application, the server 22 is further configured to obtain a calculation formula for a strain hardening capacity score based on the first eigenvalue and the second eigenvalue as follows:

[0157]

[0158] Wherein, D represents the strain hardening capacity fraction; A1 represents the first eigenvalue; and A2 represents the second eigenvalue.

[0159] As a specific embodiment of the present application, the server 22 is also used to determine that the ECC material has stable strain hardening ability if the strain hardening capacity score is greater than or equal to 3n; otherwise, it is determined that it does not have stable strain hardening ability; n is the number of cracks that have been generated when the tensile stress of the ECC material reaches the maximum.

[0160] The server involved in the embodiments of the present application can be an independent physical server, a server cluster or a distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN, as well as big data and artificial intelligence platforms.

[0161] It should be clear that the present application can accurately compare the strain hardening capacity of ECC materials through the ECC material testing system, which is conducive to selecting suitable ECC materials in various projects.

[0162] After introducing the ECC material testing system proposed in the embodiments of the present application, a computer-readable storage medium proposed in the embodiments of the present application is introduced below. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the ECC material testing method described in any of the above embodiments.

[0163] An embodiment of the present application also relates to a processor, which includes multiple storage units for calling a computer program or computer instruction stored in the memory so that the processor executes the ECC material testing method described in any of the above embodiments.

[0164] For example, in an embodiment of the present application, the processor is an integrated circuit chip with signal processing capabilities. For example, the processor can be an FPGA, a general-purpose processor, a DSP, an ASIC or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, a SoC, a CPU, a network processor (network processor, NP), a microcontroller unit (microcontroller unit, MCU), a PLD or other integrated chip, which can implement or execute the disclosed methods, steps and logic block diagrams in the embodiments of the present application. In a possible implementation, the embodiment of the present application also provides a computer-readable storage medium, the computer-readable storage medium stores a program code, and when the program code is run on the computer, the computer executes the embodiment of the test method of the above-mentioned ECC material.

[0165] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0166] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0167] In the several embodiments provided in the embodiments of the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as 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 mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0168] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0169] In addition, each functional module in each embodiment of the present application can be integrated into a processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above-mentioned integrated module can be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium.

[0170] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0171] The computer program product includes one or more computer instructions. When the computer program is loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website site, a computer, a server, or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means to another website site, computer, server, or data center. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or a data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk Solid State Disk (SSD)), etc.

[0172] The technical solutions provided in the embodiments of the present application are introduced in detail above. The principles and implementation methods of the embodiments of the present application are explained by using specific examples in the embodiments of the present application. The description of the above embodiments is only used to help understand the methods and core ideas of the embodiments of the present application. At the same time, for those skilled in the art, according to the ideas of the embodiments of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the embodiments of the present application.

Claims

1. A method for testing ECC materials, characterized in that: include: Obtaining tensile test data of the ECC material; The tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; Based on the tensile test data, obtaining a first eigenvalue and a second eigenvalue; The first characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the ECC material first generates cracks; the second characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum; Obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue; determining a strain hardening capacity of the ECC material based on the strain hardening capacity score; The obtaining of a first characteristic value based on the tensile test data comprises: Based on the tensile test data, a first time value is obtained; the first time value is the time value when the ECC material first generates cracks; Based on the first time value, obtaining a first strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and a corresponding test time value; Based on the first strain value, obtaining a first stress value by a tensile stress-strain function; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; Based on the first stress value and the first strain value, obtaining a first characteristic value; The calculation formula for obtaining the first characteristic value based on the first stress value and the first strain value is as follows: in, represents the first eigenvalue; represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; The obtaining of a second characteristic value based on the tensile test data comprises: Based on the tensile test data, a second time value is obtained; the second time value is the time value when the tensile stress of the ECC material reaches a maximum; Based on the second time value, obtaining a second strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and the corresponding test time value; Based on the second strain value, obtaining a second stress value by a tensile stress-strain function; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; Based on the second stress value and the second strain value, obtaining a second characteristic value; The calculation formula for obtaining the second characteristic value based on the second stress value and the second strain value is as follows: in, represents the second eigenvalue; represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; The calculation formula for obtaining the strain hardening capacity fraction based on the first eigenvalue and the second eigenvalue is as follows: Where D represents the strain hardening capacity fraction; represents the first eigenvalue; represents the second eigenvalue.

2. The method for testing ECC materials according to claim 1, characterized in that: The determining of the strain hardening capacity of the ECC material based on the strain hardening capacity score includes: if the strain hardening capacity score is greater than or equal to 3n, determining that the ECC material has stable strain hardening capacity; otherwise, determining that it does not have stable strain hardening capacity; n is the number of cracks that have been generated when the tensile stress of the ECC material reaches a maximum.

3. A testing device for ECC materials, characterized in that: include: A reading module, used for obtaining the tensile test data of the ECC material; The tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; A processing module, configured to obtain a first eigenvalue and a second eigenvalue based on the tensile test data; The first characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the ECC material first generates cracks; the second characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum; and, obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue; and, determining a strain hardening capacity of the ECC material based on the strain hardening capacity score; The processing module is further used to obtain a first time value based on the tensile test data; the first time value is the time value when the ECC material first generates a crack; And, based on the first time value, obtaining a first strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and the corresponding test time value; and, based on the first strain value, obtaining a first stress value from a tensile stress-strain function; The tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; and, obtaining a first characteristic value based on the first stress value and the first strain value; The processing module is further configured to obtain a calculation formula for a first eigenvalue based on the first stress value and the first strain value as follows: in, represents the first eigenvalue; represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; represents tensile strain; The processing module is further used to obtain a second time value based on the tensile test data; the second time value is a time value when the tensile stress of the ECC material reaches a maximum; And, based on the second time value, obtaining a second strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and the corresponding test time value; And, based on the second strain value, obtaining a second stress value by a tensile stress-strain function; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; and, based on the second stress value and the second strain value, obtaining a second characteristic value; The processing module is further configured to obtain a calculation formula for a second characteristic value based on the second stress value and the second strain value as follows: in, represents the second eigenvalue; represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; The processing module is further configured to obtain a calculation formula for a strain hardening capacity score based on the first eigenvalue and the second eigenvalue as follows: Where D represents the strain hardening capacity fraction; represents the first eigenvalue; represents the second eigenvalue.

4. The testing device for ECC material according to claim 3, characterized in that: The processing module is also used to determine that the ECC material has stable strain hardening ability if the strain hardening ability score is greater than or equal to 3n; otherwise, determine that it does not have stable strain hardening ability; n is the number of cracks that have been generated when the tensile stress of the ECC material reaches the maximum.

5. A testing system for ECC materials, characterized in that: include: A reader, for obtaining tensile test data of the ECC material; The tensile test data at least includes a tensile stress-strain function, a plurality of tensile stress values, tensile strain values ​​corresponding to the tensile stress values, and a test time value; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; A server, configured to obtain a first eigenvalue and a second eigenvalue based on the tensile test data; The first characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the ECC material first generates cracks; the second characteristic value is at least used to characterize the magnitude of the matrix energy consumption when the tensile stress of the ECC material reaches the maximum; and, obtaining a strain hardening capacity score based on the first eigenvalue and the second eigenvalue; and, determining a strain hardening capacity of the ECC material based on the strain hardening capacity score; The server is further configured to obtain a first time value based on the tensile test data; the first time value is a time value when a crack first occurs in the ECC material; And, based on the first time value, obtaining a first strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and the corresponding test time value; and, based on the first strain value, obtaining a first stress value from a tensile stress-strain function; The tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; and, obtaining a first characteristic value based on the first stress value and the first strain value; The server is further configured to obtain a calculation formula for a first characteristic value based on the first stress value and the first strain value as follows: in, represents the first eigenvalue; represents the first stress value; represents the first strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; represents tensile strain; The server is further configured to obtain a second time value based on the tensile test data; the second time value is a time value when the tensile stress of the ECC material reaches a maximum; And, based on the second time value, obtaining a second strain value by a stretching time strain function; the stretching time strain function is obtained by fitting each stretching strain value and the corresponding test time value; And, based on the second strain value, obtaining a second stress value by a tensile stress-strain function; the tensile stress-strain function is obtained by fitting each tensile stress value and the corresponding tensile strain value; and, based on the second stress value and the second strain value, obtaining a second characteristic value; The server is further configured to obtain a calculation formula for a second characteristic value based on the second stress value and the second strain value as follows: in, represents the second eigenvalue; represents the second stress value; represents the second strain value; represents the tensile stress-strain function; Represents the first derivative function of the tensile stress-strain function; Indicates the tensile stress-strain function in [ , ]Calculus in the tensile strain range; represents tensile strain; The server is further configured to obtain a calculation formula for a strain hardening capacity score based on the first eigenvalue and the second eigenvalue as follows: Wherein, D represents the strain hardening capacity fraction; A1 represents the first eigenvalue; and A2 represents the second eigenvalue.

6. The ECC material testing system according to claim 5, characterized in that: The server is also used to determine that the ECC material has stable strain hardening ability if the strain hardening ability score is greater than or equal to 3n; otherwise, it is determined that it does not have stable strain hardening ability; n is the number of cracks that have been generated when the tensile stress of the ECC material reaches the maximum.

7. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the method for testing the ECC material according to claim 1 or 2 is implemented.

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