Method for determining Young's elastic modulus of a deformable material

Abstract

The present invention provides a method for determining the Young's elastic modulus of a deformable material, comprising: obtaining the material characteristic factor and the limit parameter of the deformable material; obtaining the boundary loading curve and the boundary loading curve according to the limit parameter of the deformable material; taking any set value on the boundary loading curve as the end point of the loading curve of the first fracturing, and then repeatedly iterating through the end point of the loading curve of the first fracturing to obtain the loading curve or the unloading curve of any fracturing process, and obtaining the Young's elastic modulus of the deformable material at the current fracturing number according to the loading curve or the unloading curve of the current fracturing number, thereby achieving the acquisition of the Young's elastic modulus corresponding to any fracturing number during the pulsed fracturing process.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum engineering, and in particular to a method for determining the Young's elastic modulus of a deformable material. Background Art

[0002] The effective development of unconventional oil and gas resources directly depends on the effect of hydraulic fracturing. The Young's modulus of reservoir rocks and proppants (a physical quantity characterizing the ability of a material to resist deformation) is crucial for simulating and predicting the effect of hydraulic fracturing. Currently, the industry regards the Young's modulus of materials during pulsed fracturing (cyclic loading / unloading) as a constant, resulting in a large simulation prediction error and sharply increasing the process risk.

[0003] In the prior art, technicians can measure several elastic modulus values corresponding to multiple normal stresses and normal strains through experiments. However, in the actual pulsed fracturing process, the stress and strain may be any combination within a certain range. Therefore, the limited number of elastic modulus values measured through experiments cannot meet the mining requirements of unconventional oil and gas resources. Summary of the Invention

[0004] Aiming at the above problems of the prior art, the purpose of this article is to provide a method for determining the Young's elastic modulus of a deformable material to solve the problem that the limited number of elastic modulus values measured through experiments in the prior art cannot meet the mining requirements of unconventional oil and gas resources.

[0005] To solve the above technical problems, the specific technical solution of this article is as follows:

[0006] On the one hand, this article provides a method for determining the Young's elastic modulus of a deformable material, including:

[0007] Obtain the material characteristic factor and the limit parameter of the deformable material;

[0008] Obtain the boundary loading curve and the boundary unloading curve according to the limit parameter of the deformable material;

[0009] Determine the end point of the unloading curve of the current fracturing number according to the end point of the loading curve of the current fracturing number; or, determine the end point of the loading curve of the current fracturing number according to the end point of the unloading curve of the previous fracturing number; wherein, the end point of the loading curve of the first fracturing is any set value on the boundary loading curve;

[0010] Determine a weight parameter based on the end point of the loading curve of the current fracturing times, the end point of the unloading curve of the current fracturing times, and the material characteristic factor, and determine the unloading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve; or, determine a weight parameter based on the end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the material characteristic factor, and determine the loading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve;

[0011] Obtain the Young's elastic modulus of the deformed material of the current fracturing times according to the loading curve or unloading curve of the current fracturing times.

[0012] As an embodiment of this article, the material characteristic factor includes a plastic strain factor, an unloading energy consumption factor, a growth factor, and a loading energy consumption factor;

[0013] The limit parameters include a failure parameter and a critical elastic parameter.

[0014] As an embodiment of this article, further including, determining the end point of the unloading curve of the current fracturing times according to the end point of the loading curve of the current fracturing times:

[0015] According to the formula:

[0016]

[0017] Obtain the abscissa ε of the end point of the unloading curve of the current fracturing times U_1 , the ordinate of the end point of the unloading curve of the current fracturing times is 0; where ε L_1 is the abscissa of the end point of the loading curve of the current fracturing times, and the ordinate of the end point of the loading curve of the current fracturing times is determined according to the abscissa ε of the end point of the loading curve of the current fracturing times L_1 and the boundary loading curve; m is the plastic strain factor, ε U is the abscissa of the end point of the boundary unloading curve, ε cr is the abscissa of the critical elastic parameter, ε L is the abscissa of the failure parameter;

[0018] The boundary unloading curve is fitted according to the limit parameters of the deformed material.

[0019] As an embodiment of this article, further including, determining a weight parameter based on the end point of the loading curve of the current fracturing times, the end point of the unloading curve of the current fracturing times, and the material characteristic factor, and determining the unloading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve:

[0020] Obtain a number of weight parameters for the current number of fracturing times based on the end point of the loading curve of the current number of fracturing times, the end point of the unloading curve of the current number of fracturing times, and the unloading energy consumption factor;

[0021] Determine a number of unloading test points for the current number of fracturing times according to the weight parameters, the boundary loading curve, and the boundary unloading curve;

[0022] Fit the unloading curve of the current number of fracturing times based on the end point of the loading curve of the current number of fracturing times, the end point of the unloading curve of the current number of fracturing times, and a number of unloading test points for the current number of fracturing times.

[0023] As an embodiment of this article, the determining a number of unloading test points for the current number of fracturing times according to the weight parameters, the boundary loading curve, and the boundary unloading curve further includes:

[0024] Substitute the weight parameter f into the formula:

[0025] σ i = f×F(ε i )+(1 - f)×G(ε i )

[0026] Calculate a number of unloading test points σ i , where ε i is any value between the abscissa ε L_1 of the end point of the loading curve of the current number of fracturing times and the abscissa ε U_1 of the end point of the unloading curve of the current number of fracturing times, F(ε) is the function corresponding to the boundary loading curve; G(ε) is the function corresponding to the boundary unloading curve.

[0027] As an embodiment of this article, the determining the end point of the loading curve of the current number of fracturing times according to the end point of the unloading curve of the previous number of fracturing times further includes:

[0028] According to the formula:

[0029] ε L_2 = ε L_1 + γ(ε L - ε L_1 )

[0030] Obtain the abscissa ε L_2 of the end point of the loading curve of the current number of fracturing times, and the ordinate of the end point of the loading curve of the current number of fracturing times is determined according to the abscissa ε L_2 of the end point of the loading curve of the current number of fracturing times and the boundary loading curve; where ε L_1 is the abscissa of the end point of the unloading curve of the previous number of fracturing times, γ is the growth factor, εL is the abscissa of the damage parameter.

[0031] As an embodiment of the present invention, determining the weight parameter according to the end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the material characteristic factor, and determining the loading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes:

[0032] Obtaining a number of weight parameters of the current fracturing times according to the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the loading energy consumption factor;

[0033] Determining a number of loading test points of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve;

[0034] Fitting the loading curve of the current fracturing times according to the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and a number of loading test points of the current fracturing times.

[0035] As an embodiment of the present invention, determining a number of loading test points of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes:

[0036] Substituting the weight parameter f into the formula:

[0037] σ i = f×F(ε i )+(1 - f)×G(ε i )

[0038] Calculating a number of loading test points σ i , where ε i is any value between the abscissa ε U_1 of the unloading end point of the unloading curve of the previous fracturing times and the abscissa ε L_1 of the end point of the loading curve of the current fracturing times, F(ε) is the function corresponding to the boundary loading curve; G(ε) is the function corresponding to the boundary unloading curve.

[0039] As an embodiment of the present invention, obtaining the Young's elastic modulus of the deformed material of the current fracturing times according to the loading curve or unloading curve of the current fracturing times further includes:

[0040] Taking the derivative of the function corresponding to the loading curve or unloading curve to obtain the Young's elastic modulus of the deformed material of the current fracturing times.

[0041] As an embodiment of this article, obtaining the boundary loading curve and the boundary unloading curve according to the limit parameters of the deformation material further includes:

[0042] Continuously apply a positive pressure to the deformation material within the critical elastic parameter and the failure parameter;

[0043] Record the positive strain corresponding to different positive pressures when continuously applying the positive pressure to obtain a number of first measured data;

[0044] Fit and normalize the critical elastic parameter, the failure parameter, and the number of first measured data to obtain the boundary loading curve;

[0045] Continuously release the positive pressure on the deformation material within the critical elastic parameter and the failure parameter;

[0046] Record the positive strain corresponding to different positive pressures when continuously releasing the positive pressure to obtain a number of second measured data;

[0047] Fit and normalize the critical elastic parameter, the failure parameter, and the number of second measured data to obtain the boundary unloading curve.

[0048] Adopting the above technical solution, by obtaining the material characteristic factor and the limit parameter of the deformation material, the physical characteristics of the deformation material are realized; by obtaining the boundary loading curve according to the limit parameter of the deformation material, the boundary loading curve that can depict the positive stress and positive deformation when the deformation material is on the verge of breaking is realized; by determining the end point of the unloading curve of the current fracturing number according to the end point of the loading curve of the current fracturing number; or, determining the end point of the loading curve of the current fracturing number according to the end point of the unloading curve of the previous fracturing number; wherein, the end point of the loading curve of the first fracturing is a set value on the boundary loading curve, and it can be realized that by arbitrarily giving a set value on a loading curve, the end point of any loading process or unloading process during the cyclic loading and unloading process can be obtained; by determining the unloading curve of the current fracturing number according to the end point of the loading curve of the current fracturing number, the end point of the unloading curve of the current fracturing number, and the material characteristic factor; or, determining the loading curve of the current fracturing number according to the end point of the unloading curve of the previous fracturing number, the end point of the loading curve of the current fracturing number, and the material characteristic factor, it can be realized that after arbitrarily giving a positive stress value as the initial condition, the loading curve and unloading curve of any fracturing process can be obtained; by obtaining the Young's elastic modulus of the deformation material of the current fracturing number according to the loading curve or unloading curve of the current fracturing number, it can be realized to obtain the Young's elastic modulus corresponding to any fracturing number during the pulsed fracturing process.

[0049] In order to make the above and other objects, features and advantages of this article more obvious and understandable, the following provides preferred embodiments and, in conjunction with the accompanying drawings, detailed descriptions are as follows. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of this article or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of this article. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0051] Figure 1 Shows the overall system diagram of a method for determining the Young's elastic modulus of a deformed material in an embodiment of this article;

[0052] Figure 2 Shows the step schematic diagram of a method for determining the Young's elastic modulus of a deformed material in an embodiment of this article;

[0053] Figure 3 Shows the schematic diagram of a method for determining the boundary loading curve in an embodiment of this article;

[0054] Figure 4 Shows the schematic diagram of the boundary loading curve and the boundary unloading curve in an embodiment of this article;

[0055] Figure 5 Shows the schematic diagram of a method for determining the unloading curve of the current fracturing times in an embodiment of this article;

[0056] Figure 6 Shows the schematic diagram of predicting the first complete unloading curve in an embodiment of this article;

[0057] Figure 7 Shows the schematic diagram of a method for determining the loading curve of the current fracturing times in an embodiment of this article;

[0058] Figure 8 Shows the schematic diagram of predicting the second complete loading curve in an embodiment of this article;

[0059] Figure 9 Shows the schematic diagram of predicting the third complete loading curve in an embodiment of this article;

[0060] Figure 10 Shows the schematic diagram of predicting the third complete unloading curve in an embodiment of this article;

[0061] Figure 11 Shows the schematic diagram of predicting the fourth complete loading curve in an embodiment of this article;

[0062] Figure 12 Shows the schematic diagram of predicting the fourth complete unloading curve in an embodiment of this article;

[0063] Figure 13 Shows the stress-strain curve and function expression of the first complete loading and unloading process of the embodiments herein;

[0064] Figure 14 Shows the stress-strain curves and function expressions of the second complete loading and the second complete unloading of the embodiments herein;

[0065] Figure 15 Shows the stress-strain curves and function expressions of the third complete loading and the third complete unloading of the embodiments herein;

[0066] Figure 16 Shows the stress-strain curves and function expressions of the fourth complete loading and the fourth complete unloading of the embodiments herein;

[0067] Figure 17 Shows a schematic diagram of a device for determining the Young's elastic modulus of a deformation material according to the embodiments herein;

[0068] Figure 18 Shows a schematic diagram of a computer device according to the embodiments herein.

[0069] Description of the reference numerals in the drawings:

[0070] 11, Database;

[0071] 12, Terminal;

[0072] 13, Computing server;

[0073] 1701, Parameter acquisition unit;

[0074] 1702, Boundary determination unit;

[0075] 1703, Endpoint determination unit;

[0076] 1704, Curve determination unit;

[0077] 1705, Modulus calculation unit;

[0078] 1802, Computer device;

[0079] 1804, Processor;

[0080] 1806, Memory;

[0081] 1808, Driving mechanism;

[0082] 1810, Input / output module;

[0083] 1812, Input device;

[0084] 1814, Output device;

[0085] 1816. Presentation device;

[0086] 1818. Graphical user interface;

[0087] 1820. Network interface;

[0088] 1822. Communication link;

[0089] 1824. Communication bus. Detailed implementation manner

[0090] The technical solutions in the embodiments of this article will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this article. Obviously, the described embodiments are only a part of the embodiments of this article, rather than all the embodiments. Based on the embodiments in this article, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this article.

[0091] It should be noted that the terms "first", "second", etc. in the specification and claims of this article and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of this article described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product, or equipment that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or equipment.

[0092] As Figure 1 shown in the overall system diagram of a method for determining the Young's elastic modulus of a deformable material, including: a database 11, a terminal 12, and an operation server 13;

[0093] The database 11 is used to store the material characteristic factors and limit parameters of various deformable materials, as well as a number of positive strains and positive stresses during the loading process or unloading process of the deformable material under limit conditions. The material characteristic factors and limit parameters are obtained by experimenters and experiments. The specific experimental process is a conventional experimental method in material mechanics and will not be elaborated here. In this article, each deformable material has its own number. The Young's elastic modulus of the entire region can be characterized by representative deformable materials in the formation.

[0094] The terminal 12 is used to receive the set value of the user and the number of the deformable material to be calculated. The set value can be a specific positive deformation, and the terminal sends the received value to the operation server 13.

[0095] The operation server 13 is configured to receive the deformed material number of a user, obtain the material characteristic factors and limit parameters of the deformed material in the database 11, as well as several positive strains and positive stresses of the deformed material during the loading process or unloading process. The boundary loading curve and the boundary unloading curve are formed through the above data fitting. Then, it receives the set value of the user, calculates the end point of the loading curve of the first fracturing on the boundary loading curve, and performs iterative calculations through the end point of the loading curve of the first fracturing to calculate the Young's elastic modulus of any fracturing of the deformed material.

[0096] In this article, the deformed material can be elastoplastic rock. In the prior art, the Young's elastic modulus of elastoplastic rock is measured through indentation experiments. For example, by performing an indentation experiment on a rock slice, the displacement curve of the indenter pressing-in load is obtained, and the macroscopic elastic modulus is calculated through the indentation formula. In the prior art, the requirements for experimental equipment are very high, and the stress and strain of the rock during multiple rounds of loading and unloading are complex. The force on the rock slice is quite different from the actual situation, so there are errors in the elastic modulus results of the prior art.

[0097] In addition, during the actual pulsed fracturing process, the stress and strain may be any combination within a certain range. Therefore, the limited number of elastic modulus values measured through experiments cannot meet the exploitation requirements of unconventional oil and gas resources.

[0098] In this article, the pulsed fracturing process is a superposition process of multiple fracturing processes, that is, a process repeated through the first fracturing, the second fracturing... the nth fracturing to achieve pulsed fracturing. In this article, the fracturing process includes a loading process and an unloading process. In the art, usually, one loading process and one unloading process are completed, that is, one fracturing is completed. If the process is completed for the first time, then this fracturing process is the first fracturing. If the process is completed for the second time, then this process is the second fracturing.

[0099] For example, when pressure is applied to the deformed material, it is the loading process. When the pressure application to the deformed material is stopped and the deformed material is allowed to release pressure, it is the unloading process. Specifically, when water is injected into the deformed material, it is the loading process. When water is pumped out of the deformed material, it is the unloading process. During the repeated process of multiple fracturings, the Young's elastic modulus of the deformed material will change accordingly. For example, in the first fracturing and the second fracturing, if their positive deformations are the same, then their positive stresses must be different. Therefore, the Young's elastic modulus of the first fracturing is different from that of the second fracturing.

[0100] To solve the above problems, the embodiments of this article provide a method for determining the Young's elastic modulus of a deformed material, which can determine the Young's elastic model of any fracturing process. Figure 2It is a schematic diagram of the steps of a method for determining the Young's elastic modulus of a deformable material provided by an embodiment of this article. This specification provides the method operation steps as described in the embodiment or flowchart, but based on routine or non-creative labor, it may include more or fewer operation steps. The step order listed in the embodiment is only one way among the execution orders of numerous steps and does not represent the only execution order. When the actual system or device product is executed, it can be executed in the method order shown in the embodiment or the accompanying drawings or executed in parallel. Specifically, as Figure 2 shown, the method may include:

[0101] Step 201, obtain the material characteristic factor and the limit parameter of the deformable material.

[0102] Step 202, obtain the boundary loading curve and the boundary unloading curve according to the limit parameter of the deformable material.

[0103] Step 203, determine the end point of the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage; or, determine the end point of the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage; wherein, the end point of the loading curve of the first fracturing is any set value on the boundary loading curve.

[0104] Step 204, determine the weight parameter according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the material characteristic factor, and determine the unloading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve; or, determine the weight parameter according to the end point of the unloading curve of the previous fracturing stage, the end point of the loading curve of the current fracturing stage, and the material characteristic factor, and determine the loading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve.

[0105] Step 205, obtain the Young's elastic modulus of the deformable material of the current fracturing stage according to the loading curve or the unloading curve of the current fracturing stage.

[0106] Adopting the above technical solution, by obtaining the material characteristic factor and the limit parameter of the deformable material, the physical characteristics of the deformable material are obtained; by obtaining the boundary loading curve according to the limit parameter of the deformable material, the boundary loading curve that can depict the normal stress and normal deformation when the deformable material is on the verge of breaking is obtained; by determining the end point of the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage; or, determining the end point of the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage; wherein, the end point of the loading curve of the first fracturing stage is a set value on the boundary loading curve, and it can be realized that by arbitrarily giving a set value on a loading curve, the end point of any loading process or unloading process during the cyclic loading and unloading process can be obtained; by determining the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage and the material characteristic factor; or, determining the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage, the end point of the loading curve of the current fracturing stage and the material characteristic factor, it can be realized that after arbitrarily giving a normal stress value as the initial condition, the loading curve and unloading curve of any fracturing process can be obtained; by obtaining the Young's elastic modulus of the deformable material of the current fracturing stage according to the loading curve or unloading curve of the current fracturing stage, it can be realized that the Young's elastic modulus corresponding to any fracturing stage during the pulsed fracturing process can be obtained.

[0107] As an embodiment of this article, in step 201 of obtaining the material characteristic factor and the limit parameter of the deformable material, the material characteristic factor is obtained through material mechanics, and the limit parameter is obtained through experiments.

[0108] Specifically, several deformable materials for testing in an oilfield are obtained, and the critical elastic parameters are obtained through physical experiments, where the strain value of the critical elastic parameter is Φ cr , and the stress value of the critical elastic parameter is Ω cr . The failure parameters are also obtained through physical experiments, where the strain value of the failure parameter is Φ max , and the stress value of the failure parameter is Ω max .

[0109] As shown in Figure 3 the schematic diagram of the method for determining the boundary loading curve, as an embodiment of this article, in step 202, the boundary loading curve and the boundary unloading curve are obtained according to the limit parameter of the deformable material.

[0110] Step 301: Continuously apply a positive pressure to the deformable material within the critical elastic parameter and the failure parameter.

[0111] In this step, representative test materials are selected and a boundary loading test is carried out until point L0 (the strain value is Φ L <Φ max , and the stress value is Ω L ); in this article, point L0 can be the point corresponding to the failure parameter.

[0112] Similarly, a boundary unloading experiment is carried out at point L0 until point U0 (the strain value is Φ U , and the stress value is 0).

[0113] Step 302, record the positive strain corresponding to different positive pressures when continuously applying positive pressure, obtain a number of measured data and normalize them.

[0114] In this step, all test results are normalized according to the following formula:

[0115]

[0116]

[0117]

[0118] In the formula, Φ and Ω are the original strain value and original stress value of each measured point in the boundary loading and unloading test respectively; Φ min =0 and Ω min =0 are the minimum original strain value and original stress value among all test points in the boundary loading and unloading test respectively; Φ L and Ω L are the maximum original strain value and original stress value among all test points in the boundary loading and unloading test respectively; ε and σ are the normalized strain value and stress value of each test point respectively; E is the Young's elastic modulus corresponding to Φ and Ω.

[0119] In order to better distinguish the measured data, in this article, the measured data for obtaining the boundary loading curve can be called the first measured data, and the measured data for obtaining the boundary unloading curve can be called the second measured data.

[0120] As Figure 4 shown, a schematic diagram of the boundary loading curve and the boundary unloading curve, step 303 fits the critical elastic parameter, the failure parameter and the number of measured data to obtain the boundary loading curve.

[0121] In this step, according to a number of measured data, a cubic polynomial function is constructed, and the boundary loading curve and the boundary unloading curve are fitted and regressed, and their function forms are respectively as follows:

[0122] σ = A L ε 3 + B L ε2 +C L ε + D L , 0 ≤ ε ≤ 1

[0123]

[0124] The key points on the curve include: the origin O, with coordinates (ε o = 0, σ o = 0); the critical strain point C, with coordinates (ε cr , σ cr ); the end point L0 of the boundary loading curve, which is also the starting point of the boundary unloading curve, with coordinates (ε L = 1.0, σ L = 1.0); the end point U0 of the boundary unloading curve, with coordinates (ε U , σ U = 0).

[0125] Through the above method, the boundary loading curve and the boundary unloading curve obtained by fitting can characterize the limit parameters of the deformable material, that is, the test points above the boundary loading curve will cause the deformable material to break, and the points below the boundary loading curve will also cause the deformable material to break.

[0126] As an embodiment of this article, the material characteristic factors include a plastic strain factor, an unloading energy consumption factor, a growth factor, and a loading energy consumption factor.

[0127] The limit parameters include a failure parameter and a critical elastic parameter.

[0128] In this step, the failure parameter is the parameter measured when the deformable material is on the verge of breaking, including the normal stress and the normal deformation suffered by the deformable material when it is on the verge of breaking. The critical elastic parameter is the demarcation point between the elastic deformation and the plastic deformation of the deformable material, including the maximum normal stress and the maximum normal deformation of the deformable material having elastic deformation. When the deformable material exceeds the maximum normal stress and the maximum normal deformation, the deformable material is in plastic deformation. When the deformable material does not exceed the maximum normal stress and the maximum normal deformation, the deformable material is in elastic deformation.

[0129] Specifically, the determination methods of the plastic strain factor, the unloading energy consumption factor, the growth factor, and the loading energy consumption factor include:

[0130] Select a representative test material and conduct the first loading test to point L t (strain value Φ cr < Φ L_t < Φ L , stress value is Ω L_t ), and this section of the loading curve coincides with the boundary loading curve; then conduct the first unloading test at point L t to point U t(The strain value is Φ U_t , and the stress value is 0); after the first fracturing is completed at this time, continue to perform the second fracturing.

[0131] Subsequently, conduct the second loading test again until the loading curve of the second time intersects with the boundary loading curve, and the intersection point is L tt (The strain value is Φ L_t < Φ L_tt < Φ L , and the stress value is Ω L_tt ).

[0132] Normalize all test results according to the aforementioned formula and plot the converted loading and unloading curve. The starting point of the first unloading curve is Lt, and the coordinates are (ε L_t , σ L_t ). The end point of the first unloading curve coincides with the starting point of the second loading curve as Ut, and the coordinates are (ε U_t , σ U_t = 0), and the end point of the second loading curve is Ltt, and the coordinates are (ε L_tt , σ L_tt ).

[0133] A: Calculate the plastic strain factor m during the unloading process according to the abscissa of the key point:

[0134]

[0135] B: Calculate the energy dissipation factor β during the unloading process according to each data point (ε i , σ i ) of the first unloading test U :

[0136]

[0137]

[0138]

[0139] C: Calculate the growth factor γ of the end point of the converted loading curve according to the end point coordinates (ε L_tt , σ L_tt ) of the second loading test:

[0140]

[0141] D: Calculate the energy dissipation factor β during the loading process according to each data point (ε i , σ i ) of the second loading test L :

[0142]

[0143]

[0144]

[0145] Through the above factors, set values, and boundary loading curves, subsequent iterative methods can be performed, and then the loading curve or unloading curve at any time can be obtained.

[0146] As an embodiment of this article, determining the end point of the unloading curve of the current fracturing stage based on the end point of the loading curve of the current fracturing stage further includes:

[0147] According to the formula:

[0148]

[0149] The abscissa ε of the end point of the unloading curve of the current fracturing stage is obtained U_1 , and the ordinate of the end point of the unloading curve of the current fracturing stage is 0; where ε L_1 is the abscissa of the end point of the loading curve of the current fracturing stage, and the ordinate of the end point of the loading curve of the current fracturing stage is determined based on the abscissa ε L_1 of the end point of the loading curve of the current fracturing stage and the boundary loading curve; m is the plastic strain factor, and ε U is the abscissa of the end point of the boundary unloading curve, ε cr is the abscissa of the critical elastic parameter, and ε L is the abscissa of the failure parameter;

[0150] The boundary unloading curve is fitted based on the limit parameters of the deformed material.

[0151] After determining the end point of the unloading curve of the current fracturing process, several unloading test points therein can be estimated through the end point of the loading curve and the end point of the unloading curve of the current fracturing process.

[0152] As Figure 5 shown in the schematic diagram of the method for determining the unloading curve of the current fracturing stage, as an embodiment of this article, determining the weight parameter according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the material characteristic factor, and determining the unloading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes:

[0153] Step 501: Obtain several weight parameters of the current fracturing stage according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the unloading energy consumption factor.

[0154] In this step, according to the formula:

[0155]

[0156] The weight parameter f is calculated, where β U is the unloading energy consumption factor; it should be noted that the weight parameter f of the unloading test point may be different from that of the loading test point, so the weight parameter f of the unloading test point and the loading test point can be calculated separately.

[0157] Step 502: Determine a number of unloading test points for the current number of fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve.

[0158] Substitute the weight parameter f into the formula:

[0159] σ i = f×σ L (ε i )+(1 - f)×σ U (ε i )

[0160] Calculate a number of unloading test points σ i , where ε i is any value between the abscissa ε L_1 of the end point of the loading curve of the current number of fracturing times and the abscissa ε U_1 of the end point of the unloading curve of the current number of fracturing times.

[0161] Step 503: Fit the unloading curve of the current number of fracturing times according to the end point of the loading curve of the current number of fracturing times, the end point of the unloading curve of the current number of fracturing times, and a number of unloading test points of the current number of fracturing times.

[0162] In this step, according to the formula:

[0163] σ = A U_1 ε 3 + B U_1 ε 2 + C U_1 ε + D U_1 , ε U_1 < ε ≤ ε L_1

[0164] The unloading curve σ of the current number of fracturing times can be obtained.

[0165] As Figure 6 shown in the schematic diagram predicting the first complete unloading curve, as an embodiment of this article, obtaining the Young's elastic modulus of the deformed material of the current number of fracturing times according to the loading curve or unloading curve of the current number of fracturing times further includes:

[0166] Derive the function corresponding to the loading curve or unloading curve to obtain the Young's elastic modulus of the deformed material at the current fracturing times.

[0167] According to the formula,

[0168]

[0169] It can be seen that through the above method, an unloading curve at the current fracturing times can be obtained, and the specific function of this unloading curve is

[0170] y = 23.231x 3 -16.5x 2 +4.7738x - 0.5055

[0171] In this article, the vertical axis of the coordinate system is the normal stress σ, and the horizontal axis is the normal deformation ε.

[0172] On the other hand, after calculating the specific function of the unloading curve, the specific function of the loading curve can be calculated by a similar method.

[0173] As an embodiment of this article, determining the end point of the loading curve at the current fracturing times according to the end point of the unloading curve at the previous fracturing times further includes:

[0174] According to the formula:

[0175] ε L_2 = ε L_1 +γ(ε L -ε L_1 )

[0176] Obtain the abscissa ε L_2 of the end point of the loading curve at the current fracturing times. The ordinate of the end point of the loading curve at the current fracturing times is determined according to the abscissa ε L_2 of the end point of the loading curve at the current fracturing times and the boundary loading curve; where ε L_1 is the abscissa of the end point of the unloading curve at the previous fracturing times, γ is the growth factor, and ε L is the abscissa of the failure parameter.

[0177] After determining the end point of the loading curve at the current fracturing times, several loading test points therein can be estimated through the end point of the unloading curve at the previous fracturing times and the end point of the loading curve at the current fracturing times.

[0178] Such as Figure 7Schematic diagram of the method for determining the loading curve of the current fracturing times. As an embodiment of this article, determining the weight parameter according to the end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the material characteristic factor, and determining the loading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes:

[0179] Step 701: Obtain several weight parameters of the current fracturing times according to the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the loading energy consumption factor.

[0180] In this step, according to the formula:

[0181]

[0182] Calculate the weight parameter f, where β L is the loading energy consumption factor;

[0183] Step 702: Determine several loading test points of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve.

[0184] Substitute the weight parameter f into the formula:

[0185] σ i = f×σ L (ε i )+(1 - f)×σ U (ε i )

[0186] Calculate several loading test points σ i , where ε i is any value between the abscissa ε U_1 of the unloading end point of the unloading curve of the previous fracturing times and the abscissa ε L_1 of the end point of the loading curve of the current fracturing times.

[0187] Step 703: Fit the loading curve of the current fracturing times according to the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and several loading test points of the current fracturing times.

[0188] In this step, according to the formula:

[0189] σ = A L_2 ε 3 + B L_2 ε 2 + C L_2 ε + D L_2 , εU_1 <ε≤ε L_2

[0190] The loading curve σ of the current fracturing times can be obtained. Here, A, B, C, and D are constants.

[0191] As Figure 8 Shown in the schematic diagram for predicting the second fully loaded curve. As an embodiment of this article, based on the loading curve or unloading curve of the current fracturing times, obtaining the Young's elastic modulus of the deformed material at the current fracturing times further includes:

[0192] Taking the derivative of the function corresponding to the loading curve or unloading curve to obtain the Young's elastic modulus of the deformed material at the current fracturing times.

[0193] According to the formula,

[0194]

[0195] It can be seen that through the above method, a loading curve of the current fracturing times can be obtained, and the specific function of this loading curve is

[0196] y = 10.046x 3 -15.403x 2 +9.2406x - 1.4027

[0197] As an embodiment of this article, the Young's elastic modulus of the deformed material under any stress and strain during the second and subsequent complete unloading processes can be calculated according to steps 601 - 602. The Young's elastic modulus of the material under any stress and strain during the third and subsequent complete loading processes can be calculated according to steps 801 - 802.

[0198] In the figures of this article, L1, l2, L3, L4... respectively represent an end point on the first loading and unloading, the second loading and unloading, the third loading and unloading, and the fourth loading and unloading. Those skilled in the art can determine which fracturing process this loading and unloading is by observing which one of L1, L2, L3, L4... the end point of the curve is.

[0199] As Figure 9 Shown in the schematic diagram for predicting the third fully loaded curve. The function corresponding to the loading curve of this third fully loaded curve is

[0200] y = 11.046x 3 -20.123x 2 +13.115x - 2.3749

[0201] As Figure 10Schematic diagram showing the predicted third complete unloading curve, and the function corresponding to the unloading curve of this third complete unloading curve is

[0202] y = 26.256x 3 - 32.224x 2 + 13.987x - 2.0782

[0203] As Figure 11 shown in the schematic diagram of the predicted fourth complete loading curve, and the function corresponding to the loading curve of this fourth complete loading curve is

[0204] y = 13.544ε 3 - 26.226ε 2 + 18.098ε - 3.6752

[0205] As Figure 12 shown in the schematic diagram of the predicted fourth complete unloading curve, and the function corresponding to the unloading curve of this fourth complete unloading curve is

[0206] y = 25.155x 3 - 34.686x 2 + 16.691x - 2.7419

[0207] Experiment description:

[0208] Determine the boundary loading and unloading curve function, key points, and material characteristic factors of the material according to the loading and unloading test results, including the plastic strain factor m and energy dissipation factor β during the unloading process U , as well as the end growth factor γ and energy dissipation factor β during the loading process L . As shown in Table 1, the schematic table of material characteristic factors

[0209] Table 1

[0210]

[0211] The key points include the critical point C(0.05, 0.10), the end point L0(1.0, 1.0) of the boundary loading curve, and the end point U0(0.65, 0.00) of the boundary unloading curve. The maximum original strain value Φ among all test points of the boundary loading and unloading test L is 0.00167, and the maximum original stress value Ω L is 21.00 MPa

[0212] (1) The first complete loading and unloading process

[0213] Assume that the abscissa ε of the end point L1 of the first complete loading curve L_1 is 0.50, then it can be calculated that the abscissa ε of the end point U1 of the first complete unloading curve U_1Is 0.224. The Young's elastic modulus of the material during the first complete loading process is shown in Table 2. The Young's elastic modulus of the material during the first complete unloading process is shown in Table 3

[0214] Table 2

[0215] Normalized strain ε 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Young's modulus of elasticity E (GPa) 19.60 17.87 16.59 15.77 15.40 15.49 16.03 17.03 18.49 20.40 22.76

[0216] Table 3

[0217] Normalized strain ε 0.224 0.250 0.300 0.350 0.400 0.450 0.500 Young's modulus of elasticity E (GPa) 11.050 11.061 14.413 22.147 34.262 50.760 71.640

[0218] Through the above parameters, the stress-strain curve and the function expression of the first complete loading and unloading process can be obtained as Figure 13 shown.

[0219] (2) The second complete loading and unloading process

[0220] It can be calculated that the abscissa ε of the end point L2 of the second loading curve is L_2 0.60, and the abscissa ε of the end point U2 of the second complete unloading curve is U_2 0.29. The Young's elastic modulus of the material during the second complete loading process is shown in Table 4. The Young's elastic modulus of the material during the second complete unloading process is shown in Table 5.

[0221] Table 4

[0222] Normalized strain ε 0.22 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 Young's modulus of elasticity E (GPa) 47.13 42.07 33.62 26.84 21.73 18.28 16.51 16.40 17.96

[0223] Table 5

[0224] Normalized strain ε 0.30 0.35 0.40 0.45 0.50 0.55 0.60 Young's modulus of elasticity E (GPa) 11.81 11.09 15.03 23.63 36.89 54.81 77.40

[0225] Through the above parameters, the stress-strain curves of the second complete loading and the second complete unloading and the function expressions can be obtained as Figure 14 shown.

[0226] (3) The third complete loading and unloading process

[0227] It can be calculated that the abscissa ε of the end point L3 of the third loading curve is L_3 0.68, and the abscissa ε of the end point U3 of the third complete unloading curve is U_3 0.348. The Young's elastic modulus of the material during the third complete loading process is shown in Table 6.

[0228] The Young's elastic modulus of the material during the third complete unloading process is shown in Table 7.

[0229] Table 6

[0230] Normalized strain ε 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 Young's modulus of elasticity E (GPa) 51.62 40.23 30.97 23.86 18.89 16.06 15.37 16.82

[0231] Table 7

[0232] Normalized strain ε 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.68 Young's modulus of elasticity E (GPa) 13.57 10.19 11.77 18.30 29.78 46.21 67.59 82.80

[0233] Through the above parameters, the stress-strain curves and function expressions of the third complete loading and the third complete unloading as shown in Figure 15 can be obtained.

[0234] (4) The fourth complete loading and unloading process

[0235] It can be calculated that the abscissa ε 4’ of the normal end point L L_4′ of the fourth loading curve is 0.744. Extend the abscissa ε L_4 of the end point L4 to 0.80, then the abscissa ε U_4 of the end point U4 is 0.446. The Young's elastic modulus of the material during the fourth complete loading process is shown in Table 8. The Young's elastic modulus of the material during the fourth complete unloading process is shown in Table 9.

[0236] Table 8

[0237] Normalized strain ε 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.74 Young's modulus of elasticity E (GPa) 59.32 45.50 34.24 25.53 19.37 15.77 14.73 16.24 19.28

[0238] Table 9

[0239] Normalized strain ε 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 Young's modulus of elasticity E (GPa) 8.65 8.53 12.02 19.11 29.81 44.11 62.02 83.54

[0240] Through the above parameters, the stress-strain curves and function expressions of the fourth complete loading and the fourth complete unloading as shown in Figure 16 can be obtained.

[0241] As shown in Figure 17 is a schematic diagram of a device for determining the Young's elastic modulus of a deformable material, including:

[0242] A parameter acquisition unit 1701, configured to acquire the material characteristic factors and limit parameters of the deformable material.

[0243] A boundary determination unit 1702, configured to obtain a boundary loading curve and a boundary unloading curve according to the limit parameters of the deformable material.

[0244] An end point determination unit 1703, configured to determine the end point of the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage; or, determine the end point of the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage; wherein, the end point of the loading curve of the first fracturing is any set value on the boundary loading curve.

[0245] A curve calculation unit 1704 is configured to determine a weight parameter according to an end point of a loading curve of the current fracturing times, an end point of an unloading curve of the current fracturing times, and the material characteristic factor, and determine an unloading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve; or determine a weight parameter according to an end point of an unloading curve of the previous fracturing times, an end point of a loading curve of the current fracturing times, and the material characteristic factor, and determine a loading curve of the current fracturing times according to the weight parameter, the boundary loading curve, and the boundary unloading curve.

[0246] A modulus calculation unit 1705 is configured to obtain the Young's elastic modulus of the deformed material of the current fracturing times according to a loading curve or an unloading curve of the current fracturing times.

[0247] By adopting the above technical solution, through the parameter acquisition unit, the physical characteristics of the deformed material are obtained; through the boundary determination unit, the boundary loading curve that can depict the normal stress and normal deformation when the deformed material is on the verge of fragmentation is obtained; through the end point determination unit, it can be realized that given a set value on a loading curve arbitrarily, the end point of any loading process or unloading process during the cyclic loading and unloading process can be obtained; through the curve calculation unit, it can be realized that after arbitrarily given a normal stress value as an initial condition, the loading curve and unloading curve of any fracturing process can be obtained; through the modulus calculation unit, it can be realized that the Young's elastic modulus corresponding to any fracturing times during the pulsed fracturing process is obtained.

[0248] As Figure 18 shown, a computer device provided by an embodiment of the present invention, the computer device 1802 may include one or more processors 1804, such as one or more central processing units (CPUs), and each processing unit may implement one or more hardware threads. The computer device 1802 may also include any memory 1806 for storing any kind of information such as code, settings, data, etc. Non-limitingly, for example, the memory 1806 may include any one or more combinations of the following: any type of RAM, any type of ROM, flash memory devices, hard disks, optical discs, etc. More generally, any memory may use any technology to store information. Further, any memory may provide volatile or non-volatile retention of information. Further, any memory may represent a fixed or removable component of the computer device 1802. In one case, when the processor 1804 executes the associated instructions stored in any memory or combination of memories, the computer device 1802 may perform any operation of the associated instructions. The computer device 1802 also includes one or more drive mechanisms 1808 for interacting with any memory, such as a hard disk drive mechanism, an optical disc drive mechanism, etc.

[0249] The computer device 1802 may further include an input / output module 1810 (I / O) for receiving various inputs (via the input device 1812) and for providing various outputs (via the output device 1814). A specific output mechanism may include a presentation device 1816 and an associated graphical user interface (GUI) 1818. In other embodiments, the input / output module 1810 (I / O), the input device 1812, and the output device 1814 may not be included, and it may only be a computer device in a network. The computer device 1802 may further include one or more network interfaces 1820 for exchanging data with other devices via one or more communication links 1822. One or more communication buses 1824 couple the components described above together.

[0250] The communication link 1822 may be implemented in any way, for example, via a local area network, a wide area network (e.g., the Internet), a point-to-point connection, etc., or any combination thereof. The communication link 1822 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc. governed by any protocol or combination of protocols.

[0251] Corresponding to Figure 2 、 Figure 3 、 Figure 5 and Figure 7 For the methods in, embodiments of the present disclosure also provide a computer-readable storage medium having a computer program stored thereon, and when the computer program is run by a processor, it executes the steps of the above methods.

[0252] Embodiments of the present disclosure also provide a computer-readable instruction, wherein when the processor executes the instruction, the program therein causes the processor to execute as Figure 2 、 Figure 3 、 Figure 5 and Figure 7 shown in the methods.

[0253] It should be understood that in various embodiments of the present disclosure, the magnitudes of the serial numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present disclosure.

[0254] It should also be understood that in the embodiments of the present disclosure, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in the present disclosure generally represents an "or" relationship between the associated objects before and after.

[0255] Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of the examples have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this article.

[0256] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0257] In the several embodiments provided in this article, 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 merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed couplings, direct couplings, or communication connections to each other can be indirect couplings or communication connections through some interfaces, devices, or units, and can also be electrical, mechanical, or other forms of connection.

[0258] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments in this article.

[0259] In addition, the functional units in the various embodiments of this article can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0260] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this article, in essence, or the part that contributes to the prior art, or all or part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this article. The foregoing storage medium includes: various media that can store program codes such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0261] Specific embodiments are used in this article to elaborate on the principles and implementation manners of this article. The description of the above embodiments is only used to help understand the method and its core idea of this article; at the same time, for those of ordinary skill in the art, according to the idea of this article, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to this article.

Claims

1. A method for determining the Young's elastic modulus of a deformable material, characterized in that, Including: Obtaining the material characteristic factors and limit parameters of the deformable material; Obtaining the boundary loading curve and the boundary unloading curve according to the limit parameters of the deformable material; Determining the end point of the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage; or, determining the end point of the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage; wherein, the end point of the loading curve of the first fracturing is any set value on the boundary loading curve; Determining the weight parameter according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the material characteristic factors, and determining the unloading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve; or, determining the weight parameter according to the end point of the unloading curve of the previous fracturing stage, the end point of the loading curve of the current fracturing stage, and the material characteristic factors, and determining the loading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve; Obtaining the Young's elastic modulus of the deformable material of the current fracturing stage according to the loading curve or the unloading curve of the current fracturing stage.

2. The method for determining the Young's elastic modulus of the deformable material according to claim 1, characterized in that The material characteristic factors include the plastic strain factor, the unloading energy consumption factor, the growth factor, and the loading energy consumption factor; The limit parameters include the failure parameter and the critical elastic parameter.

3. The method for determining the Young's elastic modulus of the deformable material according to claim 2, characterized in that The step of determining the end point of the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage further includes: According to the formula: Obtain the abscissa ε of the end point of the unloading curve for the current fracturing times U_1 , and the ordinate of the end point of the unloading curve for the current fracturing times is 0; where ε L_1 is the abscissa of the end point of the loading curve for the current fracturing times, and the ordinate of the end point of the loading curve for the current fracturing times is determined according to the abscissa ε L_1 of the end point of the loading curve for the current fracturing times and the boundary loading curve; m is the plastic strain factor, ε U is the abscissa of the end point of the boundary unloading curve, ε cr is the abscissa of the critical elastic parameter, and ε L is the abscissa of the failure parameter; The boundary unloading curve is obtained by fitting according to the limit parameters of the deformable material.

4. The method for determining the Young's elastic modulus of the deformable material according to claim 3, characterized in that, The step of determining the weight parameter according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the material characteristic factors, and determining the unloading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes: Obtaining several weight parameters of the current fracturing stage according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and the unloading energy consumption factor; Determining several unloading test points of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve; Fitting to obtain the unloading curve of the current fracturing stage according to the end point of the loading curve of the current fracturing stage, the end point of the unloading curve of the current fracturing stage, and several unloading test points of the current fracturing stage.

5. The method for determining the Young's elastic modulus of the deformable material according to claim 4, characterized in that The step of determining several unloading test points of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes: Substituting the weight parameter into the formula: σ i = f × F(ε i ) + (1 - f) × G(ε i ) Calculate a number of unloading test points σ for the current number of fracturing times i , where f is the weight parameter, and ε i is the abscissa ε of the end point of the loading curve for the current number of fracturing times L_1 and any value between the abscissa ε of the end point of the unloading curve for the current number of fracturing times U_1 , F(ε i ) is the function corresponding to the boundary loading curve; G(ε i ) is the function corresponding to the boundary unloading curve.

6. The method for determining the Young's elastic modulus of the deformable material according to claim 2, characterized in that The step of determining the end point of the loading curve of the current fracturing stage according to the end point of the unloading curve of the previous fracturing stage further includes: According to the formula: ε L_2 = ε L_1 + γ(ε L - ε L_1 ) Obtain the abscissa ε of the end point of the loading curve for the current fracturing times L_2 , and the ordinate of the end point of the loading curve for the current fracturing times is determined according to the abscissa ε of the end point of the loading curve for the current fracturing times L_2 and the boundary loading curve; wherein, ε L_1 is the abscissa of the end point of the unloading curve for the previous fracturing times, γ is the growth factor, and ε L is the abscissa of the failure parameter.

7. The method for determining the Young's elastic modulus of the deformable material according to claim 6, characterized in that The step of determining the weight parameter according to the end point of the unloading curve of the previous fracturing stage, the end point of the loading curve of the current fracturing stage, and the material characteristic factors, and determining the loading curve of the current fracturing stage according to the weight parameter, the boundary loading curve, and the boundary unloading curve further includes: Obtain a number of weight parameters for the current fracturing times based on the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and the loading energy consumption factor; Determine a number of loading test points for the current fracturing times according to the weight parameters, the boundary loading curve, and the boundary unloading curve; Fit the loading curve of the current fracturing times based on the unloading end point of the unloading curve of the previous fracturing times, the end point of the loading curve of the current fracturing times, and a number of loading test points for the current fracturing times; 8. The method for determining the Young's elastic modulus of the deformable material according to claim 7, characterized in that, The determining a number of loading test points for the current fracturing times according to the weight parameters, the boundary loading curve, and the boundary unloading curve further includes: Substitute the weight parameters into the formula: σ i = f × F(ε i ) + (1 - f) × G(ε i ) Calculate a number of loading test points σ for the current number of fracturing times i , where ε i is the abscissa ε at the unloading end point of the unloading curve for the previous number of fracturing times U_1 and any value between the abscissa ε at the end point of the loading curve for the current number of fracturing times L_1 , F(ε) is the function corresponding to the boundary loading curve; G(ε) is the function corresponding to the boundary unloading curve, and f is the weight parameter.

9. The method for determining the Young's elastic modulus of the deformable material according to claim 1, characterized in that, The obtaining the Young's elastic modulus of the deformed material for the current fracturing times according to the loading curve or unloading curve of the current fracturing times further includes: Derive the function corresponding to the loading curve or unloading curve to obtain the Young's elastic modulus of the deformed material for the current fracturing times; 10. The method for determining the Young's elastic modulus of the deformable material according to claim 2, characterized in that The obtaining the boundary loading curve and the boundary unloading curve according to the limit parameters of the deformed material further includes: Continuously apply a positive pressure to the deformed material within the critical elastic parameter and the failure parameter; Record the positive strains corresponding to different positive pressures when continuously applying the positive pressure to obtain a number of first measured data; Fit and normalize the critical elastic parameter, the failure parameter, and the number of first measured data to obtain the boundary loading curve; Continuously release the positive pressure on the deformed material within the critical elastic parameter and the failure parameter; Record the positive strains corresponding to different positive pressures when continuously releasing the positive pressure to obtain a number of second measured data; Fit and normalize the critical elastic parameter, the failure parameter, and the number of second measured data to obtain the boundary unloading curve.

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