Concrete structure adaptive reinforcement method based on tensile stress gradient and terminal device

Abstract

The application belongs to the technical field of reinforcing method, and particularly discloses a concrete structure self-adapting reinforcing method based on tensile stress gradient and a terminal device, wherein the method comprises the following steps: determining a plurality of reinforcing sections of the concrete structure and the reinforcing spacing and tensile stress variation gradient of each reinforcing section; determining the gradient reduction coefficient of each reinforcing section according to the tensile stress variation gradient and the strength of the reinforcing steel used; determining the crack control coefficient of each reinforcing section according to the allowable crack width and the tensile strength of the concrete; and correcting the reinforcing spacing of the corresponding reinforcing section by using the gradient reduction coefficient and the crack control coefficient. The application can increase the reinforcing in the high gradient area, thereby more effectively controlling the development width and form of the cracks, improving the durability and fatigue performance of the component; and the application can also avoid the transitional reinforcing in the low tensile stress area, saving the amount of reinforcing steel, and achieving remarkable economic benefits.

Description

Technical Field

[0001] This invention belongs to the technical field of reinforcement methods, and specifically discloses an adaptive reinforcement method and terminal equipment for concrete structures based on tensile stress gradient. Background Technology

[0002] The current mainstream concrete reinforcement design method adopts the "equal spacing" or "equal diameter" reinforcement method (such as the "Code for Design of Concrete Structures" GB 50010). Specifically, the designer determines the amount of reinforcement based on the maximum internal forces (bending moment, shear force, etc.) of the member, and then evenly distributes the reinforcement at a fixed spacing throughout the stressed area (such as a pure bending section) or in areas with unfavorable shear forces. However, in reality, the distribution of tensile stress inside the member is not uniform, and there is a tensile stress gradient. In areas with low tensile stress, the strength of the reinforcement configured according to the maximum tensile stress is not fully utilized, resulting in steel waste. In addition, crack width is directly related to the tensile stress of the reinforcement. With uniform reinforcement, the cracks at the location of maximum tensile stress may just meet the requirements, but in areas with low tensile stress, the actual tensile stress of the reinforcement is even lower, and the control of cracks is "overdone," failing to achieve the optimal performance configuration. Summary of the Invention

[0003] The purpose of this invention is to provide an adaptive reinforcement method and terminal device for concrete structures based on tensile stress gradient, so as to solve the technical problem that existing reinforcement methods are difficult to achieve optimal configuration.

[0004] A first aspect of the present invention provides an adaptive reinforcement method for concrete structures based on tensile stress gradient, comprising:

[0005] Step 1: Determine the multiple reinforcement segments of the concrete structure and the reinforcement spacing and tensile stress variation gradient of each reinforcement segment;

[0006] Step 2: Determine the gradient reduction factor for each reinforcement segment based on the tensile stress variation gradient and the strength of the steel bars used;

[0007] Step 3: Determine the crack control coefficient for each reinforcement section based on the allowable crack width and the tensile strength of the concrete.

[0008] Step 4: Use the gradient reduction coefficient and the crack control coefficient to correct the reinforcement spacing of the corresponding reinforcement segment.

[0009] Preferably, step 2 specifically includes:

[0010] The total tensile stress variation of each reinforcement segment is determined based on the tensile stress variation gradient and the length of each reinforcement segment;

[0011] Determine the strength correction amount based on the strength of the reinforcing steel.

[0012] The gradient reduction factor for each reinforcement segment is determined by multiplying the total tensile stress change and the strength correction.

[0013] Preferably, step 3 specifically includes:

[0014] Obtain the elastic modulus of the reinforcing steel, and determine a first parameter based on the allowable crack width, the elastic modulus, and the tensile strength of the concrete;

[0015] Obtain the environmental durability factor and the maximum tensile stress of each reinforcement segment, and determine the second parameter based on the environmental durability factor and the maximum tensile stress of each reinforcement segment;

[0016] The crack control coefficient for each reinforcement segment is determined based on the quotient of the first parameter and the second parameter.

[0017] Preferably, the second parameter is determined based on the environmental durability coefficient and the maximum tensile stress of each reinforcement segment, specifically as follows:

[0018] The reinforcement influence factor is determined based on the density, diameter, and protective layer thickness of the reinforcement.

[0019] The second parameter is determined by multiplying the environmental durability factor, the maximum tensile stress in each reinforcement segment, and the steel reinforcement influence factor.

[0020] Preferably, step 4 specifically includes:

[0021] Preset construction adjustment coefficient;

[0022] The reinforcement spacing of the corresponding reinforcement segment is corrected by multiplying the structural adjustment coefficient, gradient reduction coefficient, and crack control coefficient.

[0023] Preferably, multiple reinforcement segments of the concrete structure are determined, specifically as follows:

[0024] Obtain the tensile stress contour map of the concrete structure;

[0025] Multiple tensile stress gradients are determined from the tensile stress cloud diagram, and multiple reinforcement segments are determined based on the tensile stress gradients.

[0026] Preferably, the reinforcement spacing of each reinforcement segment is determined as follows:

[0027] Integrate the principal tensile stress of the reinforced section to obtain the total tensile stress, and determine the amount of reinforcement for each reinforced section based on the total tensile stress;

[0028] Based on the length of each reinforcement segment and the amount of reinforcement, the reinforcement spacing of each reinforcement segment is determined using the equal spacing method.

[0029] A second aspect of the present invention provides a terminal device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described adaptive reinforcement method for concrete structures based on tensile stress gradient.

[0030] The adaptive reinforcement method and terminal device for concrete structures based on tensile stress gradient of the present invention have the following advantages compared with the prior art:

[0031] The adaptive reinforcement method and terminal equipment for concrete structures based on tensile stress gradient of the present invention can dynamically adjust the reinforcement spacing and steel bar type according to the real and non-uniform tensile stress field inside the concrete structure, so as to make the best use of materials and significantly reduce the amount of steel bars used while ensuring structural safety (strength, cracking, stiffness), thereby realizing the refinement and economy of concrete structure design. Attached Figure Description

[0032] Figure 1 This is a flowchart of an embodiment of the present invention: an adaptive reinforcement method for concrete structures based on tensile stress gradient. Detailed Implementation

[0033] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0034] A first aspect of this invention provides an adaptive reinforcement method for concrete structures based on tensile stress gradient, such as... Figure 1 As shown, it includes:

[0035] Step 1: Determine the multiple reinforcement segments of the concrete structure, the reinforcement spacing of each segment, and the tensile stress gradient, specifically:

[0036] Step 1.1: Determine the multiple reinforcement segments of the concrete structure, specifically:

[0037] Step 1.1.1: Obtain the tensile stress cloud diagram of the concrete structure.

[0038] According to the embodiments of the present invention, based on the finite element stress field analysis, the finite element analysis software is used to perform elastic or elastoplastic mechanical analysis on the concrete structure to obtain tensile stress contour maps.

[0039] Step 1.1.2: Determine multiple tensile stress gradients in the tensile stress cloud diagram, and determine multiple reinforcement segments based on the tensile stress gradients.

[0040] Step 1.2: Determine the reinforcement spacing for each reinforcement segment. and tensile stress variation gradient .

[0041] The gradient of tensile stress This represents the maximum value of the tensile stress gradient in each reinforced segment.

[0042] The reinforcement spacing of each reinforcement segment is determined. Specifically:

[0043] Integrate the principal tensile stresses of the reinforced section to obtain the total tensile stress, and determine the amount of reinforcement for each reinforced section based on the total tensile stress. Then, based on the length of each reinforcement segment... and reinforcement quantity The reinforcement spacing of each reinforcement segment is determined according to the equal spacing method. .

[0044] Step 2: Based on the tensile stress gradient and the strength of the steel bars used Determine the gradient reduction factor for each reinforcement segment. Specifically:

[0045] Step 2.1: Based on the tensile stress gradient and the length of each reinforcement segment Determine the total tensile stress variation in each reinforcement segment. .

[0046] Step 2.2: Based on the strength of the reinforcing steel Determine the strength correction amount .

[0047] Step 2.3: Based on the change in total tensile stress and intensity correction amount The product determines the gradient reduction factor for each reinforcement segment. As in formula (1):

[0048] (1)

[0049] In the formula, For the tensile stress variation gradient, The length of the reinforcement section. It approximately represents the total change in tensile stress (MPa) within the reinforcement section. The larger this value is, the more concentrated the tensile stress is in the reinforcement section. For the strength of the reinforcing steel, 360MPa is the maximum design strength value for HRB400. If higher strength reinforcing steel is used (such as...), ... If this term is greater than 1, it will make the absolute value of the exponent larger, leading to... Smaller, thus the spacing A denser spacing is needed to control crack development and avoid localized bond failure; if lower strength steel bars (such as...) are used... If this value is less than 1, it will partially offset the effect of high gradients, allowing for a slightly larger spacing. The gradient sensitivity coefficient determines the degree to which the algorithm responds to gradients. Its value ranges from 0.05 to 0.2 (m / MPa), and can be adjusted within this range according to the safety level and load uncertainty of the specific project.

[0050] This invention employs an exponential function to quantify the unique requirements of tensile stress non-uniformity on reinforcement spacing, and performs coupling correction between the tensile stress variation gradient and the tensile stress in the reinforcement, outputting a gradient reduction coefficient between 0 and 1. When the tensile stress changes gradient When it is 0, A value of 1 indicates that the gradient has no effect. When the gradient approaches infinity, it means that tensile stress is concentrated at this point, requiring special treatment.

[0051] Step 3: Based on the allowable crack width and the tensile strength of concrete Determine the crack control coefficient for each reinforcement section. Specifically:

[0052] Step 3.1: Obtain the elastic modulus of the reinforcing steel. According to the allowable crack width Elastic modulus and the tensile strength of concrete Determine the first parameter .

[0053] For example, the first parameter is determined according to formula (2). :

[0054] (2)

[0055] Step 3.2: Obtain the environmental durability coefficient and the maximum tensile stress in each reinforcement segment According to the environmental durability factor and the maximum tensile stress in each reinforcement segment Determine the second parameter .

[0056] Among them, based on environmental durability coefficient and the maximum tensile stress in each reinforcement segment Determine the second parameter Specifically:

[0057] Step 3.2.1: Based on the density of the reinforcing steel bars ,diameter and protective layer thickness Determine the influence factors of steel reinforcement For example, the reinforcement influence factor is determined according to the following formula. :

[0058] (3)

[0059] Step 3.2.2: Based on the environmental durability factor Maximum tensile stress in each reinforcement segment Influence factors of steel reinforcement The product of the series determines the second parameter As shown in formula (4):

[0060] (4)

[0061] In the formula, The comprehensive sensitivity coefficient, which comprehensively reflects the influence of concrete tensile strength and the bond performance between steel reinforcement and concrete on crack propagation, is set to 0.015 mm / MPa.

[0062] Step 3.3, based on the first parameter Second parameter The quotient determines the crack control coefficient for each reinforcement segment. As shown in formula (5):

[0063] (5)

[0064] In formula (5), the first parameter Allowable crack width The target is to control the crack width. Elastic modulus of steel bars and the tensile strength of concrete Placing them in molecules means that the larger they are, the more accurate the calculations will be. The larger the value, the greater the allowable reinforcement spacing. The larger the value, the more intuitively it reflects the material's good performance and strong crack resistance.

[0065] In the denominator of formula (5), The durability parameters can be determined according to the "Code for Design of Concrete Structures" GB 50010. The harsher the environment ( The larger the value, the higher the tensile stress. The larger the size, the more unfavorable the structure (protective layer). Larger diameter The larger (the larger), the more calculated The smaller the value, the more space is required for reinforcement. To suppress cracks.

[0066] This invention reconstructs the normal crack width calculation formula into an actively controlled crack control coefficient. And explicitly highlight the tensile strength of concrete. The traditional method is to "input the reinforcement and output the crack width to see if it meets the standard," while the embodiment of this invention is to "input the allowable crack width and the maximum tensile stress." Output a crack control coefficient "To determine how many times the reinforcement should be adjusted."

[0067] Step 4: Utilize the gradient reduction factor Crack control coefficient Adjust the reinforcement spacing of the corresponding reinforcement section. Specifically:

[0068] Step 4.1: Preset the structural adjustment coefficient Construct adjustment coefficients This can prevent extreme situations from occurring during calculations that would prevent construction from being carried out or fail to meet specifications, and adjustments can be made as needed.

[0069] Step 4.2: Construct adjustment coefficients Gradient reduction coefficient and crack control coefficient The product correction corresponds to the reinforcement spacing of the reinforcement segment. As shown in formula (6):

[0070] (6)

[0071] The final reinforcement spacing of the reinforcement segment obtained in the embodiment of the present invention It can meet the requirements for strength, gradient tensile stress analysis, and cracking.

[0072] The final overall reinforcement spacing output by this invention is a continuous or segmented gradient variation spacing corresponding to the tensile stress field, rather than one or two fixed values. The reinforcement method of this invention is a safe, durable, and economical method. Furthermore, to facilitate a clear and intuitive understanding of the final reinforcement scheme, the information regarding reinforcement spacing and the concrete structure can be expressed in the form of tables or diagrams.

[0073] A second aspect of the present invention provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described adaptive reinforcement method for concrete structures based on tensile stress gradient.

[0074] This invention provides an adaptive reinforcement method and terminal device for concrete structures based on tensile stress gradient. This method and terminal device can dynamically adjust the spacing and type of reinforcing bars according to the actual, non-uniform tensile stress field inside the concrete structure, making the best use of materials. While ensuring structural safety (strength, crack resistance, stiffness), it significantly reduces the amount of reinforcing bars used, achieving refined and economical structural design.

[0075] The adaptive reinforcement method and terminal equipment for concrete structures based on tensile stress gradient of the present invention have the following beneficial effects:

[0076] 1. Economic efficiency: By avoiding "over-reinforcement" in low tensile stress areas, 10% to 25% of the amount of tensile steel bars can be saved, resulting in significant economic benefits.

[0077] 2. Safety: By taking into account the tensile stress gradient and increasing the reinforcement density in high gradient areas, the width and shape of cracks can be controlled more effectively, which may improve the durability and fatigue performance of concrete structures.

[0078] 3. The deep integration of structural design with algorithms, digital tools and finite element method has promoted the leap from "experience-based" to "refined" structural design.

[0079] 4. Feasibility: The final output can be a clear reinforcement drawing. Although the spacing of the steel bars is no longer uniform, the rules are clear, and the construction unit only needs to construct according to the drawing, which is easy to promote.

[0080] The above descriptions are merely a few embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any modifications or alterations made by those skilled in the art without departing from the scope of the technical solution of the present invention using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for self-adapting reinforcement of a concrete structure based on tensile stress gradient, characterized in that, The application relates to a method for self-adapting reinforcement of a concrete structure based on a tensile stress gradient, comprising the following steps: Step 1: determining a plurality of reinforcement sections of the concrete structure and reinforcement spacing and tensile stress gradient of each reinforcement section; Step 2: determining a gradient reduction coefficient of each reinforcement section according to the tensile stress gradient and the strength of the used steel, specifically: determining a total tensile stress variation of each reinforcement section according to the tensile stress gradient and the length of each reinforcement section; determining a strength correction amount according to the strength of the steel; determining the gradient reduction coefficient of each reinforcement section according to the product of the total tensile stress variation and the strength correction amount; Step 3: determining a crack control coefficient of each reinforcement section according to the allowable crack width and the tensile strength of the concrete, specifically: Obtain the elastic modulus of the steel bar According to the allowable crack width The elastic modulus and the tensile strength of concrete Determine the first parameter : ; obtaining an environmental durability coefficient and a maximum tensile stress of each reinforcing segment , according to the environmental durability coefficient and a maximum tensile stress of each reinforcing segment determining a second parameter : wherein is a comprehensive sensitivity coefficient, , is a thickness of a protective layer, is a diameter of the reinforcing steel, is a density of the reinforcing steel; determining a crack control factor for each reinforcement segment based on a quotient of the first parameter and the second parameter ​ Step 4: correcting the reinforcement spacing of the corresponding reinforcement section by using the gradient reduction coefficient and the crack control coefficient.

2. The method of claim 1, wherein the method is characterized by, Step 4 is specifically: presetting a structure adjustment coefficient; correcting the reinforcement spacing of the corresponding reinforcement section by using the connected product of the structure adjustment coefficient, the gradient reduction coefficient and the crack control coefficient.

3. The method of claim 1, wherein the method is characterized by, A plurality of reinforcement sections of the concrete structure are determined, specifically: a tensile stress nephogram of the concrete structure is obtained; a plurality of tensile stress gradients of the tensile stress nephogram are determined, and a plurality of reinforcement sections are determined according to the tensile stress gradients.

4. The method of claim 1, wherein the method is characterized by, The reinforcement spacing of each reinforcement section is determined, specifically: the main tensile stress of each reinforcement section is integrated to obtain a total tensile stress, and the reinforcement amount of each reinforcement section is determined according to the total tensile stress; the reinforcement spacing of each reinforcement section is determined according to the length of each reinforcement section and the reinforcement amount by using the equal-interval method.

5. A terminal device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the steps of the method for self-adapting reinforcement of the concrete structure based on the tensile stress gradient according to any one of claims 1 to 4.

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