Fiber asphalt flexible anti-cracking seal coat parameter selection and design method

Abstract

A method for parameter selection and design of fiber-reinforced asphalt flexible crack-resistant sealing layer includes: S1, establishing a strength prediction model: combining feature design and support vector machine algorithms, by constructing nonlinear coupling features of asphalt content, fiber content, and fiber length, a support vector regression model is trained to obtain a prediction model for the tensile strength of the bridge deck waterproofing layer under different material combinations; S2, establishing a theoretical model for the waterproofing performance of the waterproofing layer: based on the cracking principle of the waterproofing layer and the stress balance of the waterproofing layer, the functional relationship between the equivalent stress length of the waterproofing layer, the thickness of the waterproofing layer, and the tensile strength is obtained, and the critical crack width W of the waterproofing layer is obtained. t The theoretical model and the correlation coefficient of waterproof performance of waterproof layers with different material combinations; S3, Design of bridge deck waterproof layer: Based on the crack width of the bridge deck, combined with the prediction model of the tensile strength of the bridge deck waterproof layer and the theoretical model of the waterproof performance of the bridge deck cracked waterproof layer, the material combination of the waterproof layer with the best economic efficiency is selected.

Description

Technical Field

[0001] This invention relates to the field of bridge deck waterproofing technology, and more specifically, to a method for selecting and designing parameters for a fiber-reinforced asphalt flexible crack-resistant seal layer. Background Technology

[0002] Waterproofing layers or sealing layers are indispensable components of bridge, tunnel, and road structures. They are thin layers of asphalt mixture laid to seal surface voids and prevent moisture from penetrating the surface or base layer. The primary function of waterproofing layers or sealing layers is to prevent rainwater, snowmelt, and de-icing salt from seeping into the bridge deck, tunnel, and pavement structure layers, effectively avoiding problems such as concrete carbonation and steel corrosion, thereby improving the durability and service life of road, bridge, and tunnel infrastructure. Simultaneously, waterproofing layers also prevent surface peeling, voids, freeze-thaw damage, and other defects, improving the adhesion between the pavement layer and the main structure, and ensuring the overall stability and safety of the structure. As a crucial measure in long-life infrastructure design, waterproofing layers play a key role throughout the entire life cycle of infrastructure. With the increasing demands on the performance of waterproofing layers in road surface structures, fiber-reinforced asphalt flexible crack-resistant sealing materials are gradually being widely used due to their excellent mechanical properties.

[0003] Currently, the performance of waterproofing layers in infrastructure applications is influenced by multiple factors, primarily including the amount of asphalt used, the amount of fiber used, and the fiber length. In actual construction, the selection of waterproofing materials often relies on experience or multiple trials, leading to inefficient material selection for bridge deck waterproofing, high time and economic costs, and difficulty in quickly choosing the right materials, thus delaying the construction period.

[0004] Therefore, there is an urgent need for a method for selecting and designing sealing parameters that can improve design efficiency and accuracy. Summary of the Invention

[0005] This invention provides a parameter selection and design method for fiber-reinforced asphalt flexible crack-resistant sealing layers. Based on feature design and artificial intelligence optimization, it solves the problems of low efficiency, high cost, and poor adaptability in traditional methods. By constructing nonlinear coupling features of asphalt content, fiber content, and fiber length, it trains a support vector regression model to accurately predict the tensile strength of the waterproof layer and guides the selection of the optimal parameter combination.

[0006] The technical solution adopted by this invention to solve its technical problem is a method for selecting and designing parameters for a fiber-reinforced asphalt flexible crack-resistant sealing layer. This method is used to quickly determine the material of the waterproof layer, and includes the following steps:

[0007] S1. Establish a strength prediction model: Combining physical feature design with support vector machine algorithm, by constructing nonlinear coupling features of asphalt content, fiber content and fiber length, a support vector regression model is trained to obtain a prediction model of the tensile strength of the waterproof layer under different material combinations.

[0008] S2. Establish a theoretical model for the waterproofing performance of the concrete cracked waterproofing layer: Based on the cracking principle and the force balance of the waterproofing layer, the equivalent stress length S, the thickness t, and the tensile strength σ of the waterproofing layer can be obtained. t The functional relationship between them can be determined. Furthermore, based on the fact that the width of the bridge deck crack is actually the tensile length of the waterproofing coating, the critical crack width W of the concrete beam when the waterproofing layer fails can be derived. t The functional relationship between K, C, and α was used to construct a test beam including a waterproof layer. A loading test was conducted to induce cracking in the test beam, followed by crack propagation and water seepage. The critical crack width W at which the test beam cracked and began to seep water was measured. t The performance of the waterproof layer was tested using test beams with multiple waterproof layers of different material combinations to calculate the K, C, and α values ​​of the waterproof layer with different material combinations. K, C, and α are the correlation coefficients of the waterproof performance of the waterproof layer.

[0009] S3. Design of the bridge deck waterproofing layer: Based on the crack width of the bridge deck, combined with the prediction model of the tensile strength of the bridge deck waterproofing layer and the theoretical model of the waterproofing performance of the bridge deck crack waterproofing layer, and considering the optimal economic factors, the material combination of the waterproofing layer is selected.

[0010] Preferably, the predictive model for obtaining the tensile strength of the bridge deck waterproofing layer under different material combinations in step S1 includes the following steps:

[0011] S101. Based on engineering experience and bridge deck waterproofing layer specifications, predict the range of asphalt usage, fiber usage, and fiber length.

[0012] S102. Using an orthogonal design method, specimens are prepared for different material combinations and tensile tests are conducted on the specimens to obtain the tensile force and tensile strength of the specimens. Based on the characteristics of the changes in the combined materials in the specimens with different material combinations, characteristic functions X1, X2, and X3, including the variation law of each parameter, are obtained, where X1 is the characteristic function of asphalt content, X2 is the characteristic function of fiber content, and X3 is the characteristic function of fiber length.

[0013] S103. Using X1, X2, and X3 as input features of the support vector regression model, the input feature is tensile strength σ. t To obtain the tensile strength σ of the bridge deck waterproofing layer under different combinations, the output features are learned and predicted. t ;

[0014] Preferably, assuming the amount of asphalt (kg / m2) is A, the amount of glass fiber (g / m2) is G, and the length of the glass fiber (cm) is L, then X1 = A.

[0015] Among the X2 characteristic functions λ is the fiber / asphalt ratio, reflecting the density of the fiber filler; λ is the rate of influence of the fiber dosage; c is a constant, reflecting the weight of the asphalt dosage on the fiber dosage; L is the fiber length; L0 is the optimal fiber length; h is a parameter controlling the rate of influence of the fiber.

[0016] The principle behind the above feature design is as follows: the amount of asphalt directly affects the waterproofing layer design, hence X1 = A; when the fiber length is constant, there is a mutually restrictive relationship between the amount of asphalt and the amount of fiber. When the amount of asphalt is constant, as the amount of fiber decreases, there are not enough fibers to contact the asphalt, resulting in more free asphalt and thus a decrease in tensile strength; when the amount of fiber increases to a certain extent, there is not enough free asphalt to contact the excess fiber interface, and the resulting free fibers have limited effect on improving the tensile strength of the structure; that is, too few fibers result in insignificant reinforcement, while too many fibers lead to poor dispersion (decreased encapsulation). Therefore, the interaction effect between the amount of fiber and the amount of asphalt is quite significant, and the relationship between the amount of fiber and the amount of asphalt can be described by a multiplicative function. When the fiber length is too short, insufficient fiber overlap leads to decreased strength; when the fiber length is too long, poor fiber uniformity also affects strength. Fiber length is usually optimal within a certain range, exhibiting a peak-type correction. Therefore, the influence of fiber length is relatively small, and its impact on tensile strength is described using a function combining linear and exponential decay.

[0017] Preferably, when the fiber content G = 0, the waterproof layer is entirely made of asphalt, and the tensile strength σ of the waterproof layer is... t Fixed σ t =σ0.

[0018] Preferably, the allowable stretching stroke ΔS of the waterproof layer of the same thickness under the same length conditions is the same, that is, the waterproof layer of length S fails when stretched to S+ΔS.

[0019] Preferably, the stress of the waterproof layer including fibers is calculated as follows:

[0020] For ease of calculation, we take the unit width as the calculation unit. Through the force balance of the waterproof layer, we know that F = τS / 2, and F is the axial tensile force of the waterproof layer, i.e., F = tσ. t ;

[0021] Therefore, τS / 2=tσ t ,Right now Where t is the thickness of the waterproof layer, t = m 沥青 / ρ 沥青 +m 纤维 / ρ 纤维 m 沥青 m 纤维 The mass of asphalt and fiber of the waterproof layer per unit area; σ t τ represents the tensile strength of the waterproof layer; τ represents the ultimate shear stress of the waterproof coating.

[0022] Preferably, when the waterproof layer fails due to water seepage, the tensile length of the waterproof layer is equal to the width of the crack in the bridge deck, and the critical crack width W of the waterproof layer is... t =ΔS+Ct α ,make but

[0023] Preferably, when selecting the material combination of the waterproof layer in step S3, when The material combination of the waterproof layer is then considered to meet the waterproofing requirements, where η is the safety factor and W f Cracks are allowed in the structural design.

[0024] Preferably, based on the material combination of the waterproof layer that meets the waterproofing requirements, the economically optimal solution for the material combination of the waterproof layer per unit area is selected, and the material price per unit area of ​​the waterproof layer is P = m. 沥青 ·p 沥青 +m 纤维 ·p 纤维 , where p 沥青 p 纤维 These are the unit price per unit area for asphalt and the unit price per unit area for fiber, respectively.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention discloses a parameter selection and design method for fiber-reinforced asphalt flexible crack-resistant sealing layer. Based on feature design and artificial intelligence optimization, it addresses the problems of low efficiency, high cost, and poor adaptability in traditional methods. By constructing a nonlinear coupling feature of asphalt content, fiber content, and fiber length, and training a support vector regression model, it achieves accurate prediction of the tensile strength of the waterproof layer, guiding the selection of the optimal combination of material parameters for the bridge deck waterproof layer. This further improves the efficiency of material selection for the bridge deck waterproof layer, shortens the construction period, and reduces time and economic costs associated with material selection. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the stress balance of the waterproof layer in the parameter selection and design method of the fiber-reinforced asphalt flexible crack-resistant sealing layer of the present invention;

[0028] Figure 2 This is a diagram showing the crack development and waterproofing layer failure in a concrete beam (t = 2 mm) in Example 2 of the fiber-reinforced asphalt flexible crack-resistant sealing layer parameter selection and design method of the present invention.

[0029] Figure 3 This is a photograph of the specimen preparation process in the specimen preparation and testing procedure of Embodiment 1 of the fiber-reinforced asphalt flexible crack-resistant seal layer parameter selection and design method of the present invention;

[0030] Figure 4 This is a photograph of the tensile test of the waterproof layer in the specimen preparation and testing process of Embodiment 1 of the fiber-reinforced asphalt flexible crack-resistant sealing layer parameter selection and design method of the present invention;

[0031] Figure 5 This is a photograph of the test beam fabrication in Embodiment 1 of the fiber-reinforced asphalt flexible crack-resistant seal layer parameter selection and design method of the present invention;

[0032] Figure 6 This is a photograph of a four-point loading test in Embodiment 1 of the fiber-reinforced asphalt flexible crack-resistant seal layer parameter selection and design method of the present invention;

[0033] Figure 7 This is a photograph (t=2mm) of the crack development and waterproofing layer failure in a concrete beam in Example 2 of the parameter selection and design method for the fiber-reinforced asphalt flexible crack-resistant sealing layer of the present invention.

[0034] Figure 8 This is a photograph of the actual construction after selecting parameters according to the design method in Example 2 of the fiber-reinforced asphalt flexible crack-resistant sealing layer of the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] Numerous specific details are set forth in the following description to enable those skilled in the art to fully understand the invention. However, the invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0037] In the description of the embodiments of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0039] like Figure 1 As shown, a method for selecting and designing parameters for a fiber-reinforced asphalt flexible crack-resistant seal layer is presented. This method is used to quickly determine the material of the waterproof layer and includes the following steps:

[0040] S1. Establish a strength prediction model: Combining physical feature design with support vector machine algorithm, by constructing nonlinear coupling features of asphalt content, fiber content and fiber length, a support vector regression model is trained to obtain a prediction model of the tensile strength of the bridge deck waterproof layer under different material combinations.

[0041] S101. Based on engineering experience and the requirements of bridge deck waterproofing layer specifications, predict the range of asphalt usage, fiber usage, and fiber length.

[0042] S102. Using the orthogonal design method, specimens with different material combinations are made and tensile property tests are conducted on the specimens to obtain the tensile force and tensile strength of the specimens. Based on the characteristics of the changes in the combined materials in the specimens with different material combinations, characteristic functions X1, X2, and X3, including the variation law of each parameter, are obtained, where X1 is the characteristic function of asphalt content, X2 is the characteristic function of fiber content, and X3 is the characteristic function of fiber length.

[0043] S103. Using X1, X2, and X3 as input features of the support vector regression model, the input feature is tensile strength σ. t To obtain the tensile strength σ of the bridge deck waterproofing layer under different combinations, the output features are learned and predicted. t When the fiber content G = 0, the waterproof layer is all asphalt, and the tensile strength σ of the waterproof layer is... t Regardless of the values ​​of A and L, σ is always satisfied. t=σ0, where σ0 is the tensile strength of asphalt.

[0044] Assuming the amount of asphalt used is A (kg / m2), the amount of glass fiber used is G (g / m2), and the length of the glass fiber is L (cm), then X1 = A. Among the X2 characteristic functions λ is the fiber / asphalt ratio, reflecting the density of the fiber filler; λ is the rate of influence of the fiber dosage; c is a constant, reflecting the weight of the asphalt dosage on the fiber dosage; L is the fiber length; L0 is the optimal fiber length; h is a parameter controlling the rate of influence of the fiber.

[0045] S2. Establish a theoretical model for the waterproofing performance of the bridge deck crack waterproofing layer: Based on the cracking principle and the force balance of the waterproofing layer, the equivalent stress length S of the waterproofing layer, the thickness t of the waterproofing layer, and the tensile strength σ can be obtained. t The functional relationship between them, and based on the critical crack width W of the waterproof layer. t The functional relationship between K, C, and α was used to construct a test beam including a waterproof layer. A loading test was conducted to induce cracking and water seepage in the test beam. The critical crack width W at which water seepage occurred was measured. t The performance of waterproof layers with different material combinations was tested using test beams to calculate the K, C, and α values ​​of the waterproof layers with different material combinations. K, C, and α are the correlation coefficients of the waterproof performance of the waterproof layers.

[0046] In step S2, for waterproof layers of the same thickness and unit length, theoretically, leakage begins after the waterproof layer is stretched to the point where holes appear. Therefore, regardless of whether the waterproof layer contains fiber materials, the stretching distance to cracking is the same for waterproof layers of the same thickness and length. That is, waterproofing fails when a waterproof layer of length S is stretched to S+ΔS. Here, K is the allowable elongation of the waterproof layer; C can be defined as the "waterproof thickness gain coefficient," meaning the waterproof performance of the waterproof layer increases with its thickness; α represents the exponent of material deformation during stretching, reflecting the deformation characteristics of the material during stretching. When α < 1: it means that the rate of strain increase with stress gradually slows down. When α = 1: the deformation of the material follows a linear relationship. When α > 1: it indicates that the strain growth in the plastic stage is very rapid, and the deformation of the material is very sensitive to changes in applied stress. K, C, and α can be determined through waterproof layer performance tests.

[0047] For waterproofing layers containing fiber materials, although waterproofing layers of the same thickness and length have the same failure tensile stroke, the fiber materials can effectively improve the tensile strength of the waterproofing layer, causing stress redistribution under stress. Therefore, for waterproofing layers containing fiber materials, the stress redistribution under the action of the fiber materials under tension results in a longer stress distribution range for the waterproofing layer. The specific calculation method for the stress-bearing length of the waterproofing layer is as follows. For convenience, the calculation is performed using a unit width. Through the force balance of the waterproofing layer, we know that F = τS / 2, where F is the axial tensile force of the waterproofing layer, i.e., F = tσ. t Therefore Where t is the thickness of the waterproof layer, t = m 沥青 / ρ 沥青 +m 纤维 / ρ 纤维 m 沥青 m 纤维 The mass of asphalt and fiber in the waterproof layer per unit area; σ t τ represents the tensile strength of the waterproof layer; τ is the ultimate shear stress of the waterproof coating. In summary, the stress-bearing length of the waterproof layer, including fibrous materials... When the waterproofing layer begins to leak and fail, the tensile length of the waterproofing layer equals the width of the crack in the bridge deck. The critical crack width W of the waterproofing layer... t =ΔS+Ct α ,make but

[0048] S3. Design of bridge deck waterproofing layer: Based on the crack width of the bridge deck, combined with the prediction model of the tensile strength of the bridge deck waterproofing layer and the theoretical model of the waterproofing performance of the bridge deck cracked waterproofing layer, the material combination of the waterproofing layer is selected.

[0049] When selecting the material combination for the waterproof layer in step S3, when It is assumed that the material combination of the waterproof layer meets the waterproofing requirements, where η is the safety factor, which is obtained through experiments based on the existing waterproof layer design. f To allow for cracks in the structural design, the allowable crack width for a traditional waterproof layer bridge deck is 0.2mm. During the test, when water seepage occurred, the crack width was 0.89mm. 0.89 / 0.2 = 4.45, therefore the safety factor η needs to be greater than 4.45. For safety reasons, the safety factor is taken as 6. Based on the material combination of the waterproof layer that meets the waterproofing requirements, the most economical solution for the material combination per unit area of ​​the waterproof layer is selected. Thus, the material combination with the best material economy among the combinations that meet the waterproofing conditions is chosen. The material price per unit area of ​​the waterproof layer is P = m 沥青 ·p 沥青 +m 纤维 ·p 纤维 , where p 沥青 p纤维 These are the unit price per unit area for asphalt and the unit price per unit area for fiber, respectively.

[0050] In this embodiment, the design method is based on feature design and artificial intelligence-optimized parameter selection of fiber asphalt bridge deck waterproofing layer. It constructs the nonlinear coupling characteristics of the influencing factors of the waterproofing layer, trains the support vector regression model, realizes accurate prediction of the tensile strength of different material combinations, and guides the selection of the optimal parameter combination of materials for the bridge deck waterproofing layer. This further improves the efficiency of material selection for the bridge deck waterproofing layer, shortens the construction period, and reduces time costs and economic costs of material selection.

[0051] Furthermore, in Example 1:

[0052] Based on engineering experience and relevant regulations (specifications) for bridge deck waterproofing layers, the asphalt content, fiber content, and fiber length range are preliminarily determined. Here, the range is calculated per meter. 2 Based on the dosage, the dosage of SBS modified asphalt is 1.2-2 kg / m³. 2 Fiber usage is 45-100g / m² 2 The fiber length is 3-8cm.

[0053] Using orthogonal design, tensile specimens of different material combinations were fabricated and tensile property tests were conducted to obtain their tensile force and tensile strength.

[0054] Specimen fabrication and testing procedures: as follows Figure 2 As shown, a mold with dimensions of 10cm x 7cm x 3cm is used. A layer of silicone paper is laid in the mold, and the lower layer of asphalt, fiber, and upper layer of asphalt are applied in sequence according to the designed ratio. After the strength reaches the design value, the mold is demolded.

[0055] Experiment: such as Figure 3 As shown, the specimen is clamped at both ends of the short side using a clamp, and a loading instrument is used to slowly load it in a displacement-controlled manner. The load value of the loading instrument is recorded, thereby calculating the tensile strength of different material combinations.

[0056] The combined test strengths for the examples are shown in Table 1 below:

[0057] <![CDATA[Asphalt dosage (kg / m 2 )]]> <![CDATA[Fiber dosage (g / m 2 )]]> Fiber length (cm) Tensile strength (MPa) 1.2 45 4 1.329 1.2 60 5 1.411 1.2 75 6 1.394 1.2 75 5 1.146 1.5 75 6 1.102 1.8 45 6 0.931 1.8 60 4 0.993 1.8 75 5 0.837 1.4 45 4 1.172 1.4 60 4 1.322 1.4 75 4 1.133 1.5 45 4 1.222 1.5 60 4 1.3 1.6 45 4 1.211 1.6 75 4 1.123 any 0 any 0.33

[0058] Based on the characteristics of the high-performance flexible crack-resistant sealing layer composite material in the table above, the characteristic functions X1, X2, and X3 of the variation law of each parameter are calculated. These X1, X2, and X3 are then used as input features for support vector regression (SVM). The tensile strength σ... t The following table can be obtained as the output features.

[0059] Table 2: Tensile Strength σ t Forecast table

[0060]

[0061]

[0062] Learning and prediction are performed based on the training data in Table 2, which can accurately obtain the strength of high-performance flexible crack-resistant sealing layers under different material combinations.

[0063] Several test beams (simulating bridge deck cracking) were fabricated, and waterproof layers with different material combinations were applied to the test beams. The tensile strength of each material combination waterproof layer can be determined by the aforementioned prediction model. The waterproof performance test scheme for the waterproof layer is as follows:

[0064] like Figure 4 and 5 As shown, a four-point loading test was conducted to cause cracks in the test beam. The cracks were located below a pre-set water trough. When water seepage occurred in the beam, it indicated that the waterproofing layer had failed. Simultaneously, the crack width W was measured using a crack measuring instrument. t Through performance tests of multiple waterproof layers composed of different materials, the crack width W was determined. t Substitute the result into the critical crack width of the waterproof layer The values ​​of K, C, and α can be obtained, thereby determining the waterproofing performance of different material combinations on the bridge deck.

[0065] Based on the prediction model of the crack width of the bridge deck combined with the tensile strength of the bridge deck waterproofing layer and the theoretical model of the waterproofing performance of the bridge deck cracked waterproofing layer, the material combination of the waterproofing layer is selected.

[0066] Furthermore, based on the above-mentioned parameter selection and design method for fiber-reinforced asphalt flexible crack-resistant sealing layer, this invention also provides Embodiment Two, which obtains the parameter values ​​of the waterproof performance model based on the design method of this invention:

[0067] To determine K, C, and α, waterproofing performance tests were conducted on beams coated with a fiber-free waterproofing layer. The waterproofing layer thicknesses were 1 mm, 1.5 mm, and 2 mm, respectively. The measured crack widths in the concrete beams at the point of waterproofing layer failure were 0.33 mm, 0.59 mm, and 0.89 mm, respectively. That is, at t = 1 mm, W... t =0.33mm, and so on. From the above, we know σ t =0.33 MPa, τ = 0.4 MPa. Substitute these values ​​into the formula. Solving the equation, we get K = 0.08; C = 0.2; α = 1.6; that is...

[0068] In actual engineering design, it is necessary to meet the following requirements. The requirements, namely the combination and thickness of the selected waterproof layer materials, must meet the following requirements. For a working concrete slab with cracks, the allowable crack width is 0.2 mm.

[0069]

[0070] Simultaneously, based on the strength prediction model, the tensile strength σ of the sealing layer with different material combinations can be obtained. t The following material combinations that meet the conditions can be obtained. To facilitate material quantity control and construction, the minimum unit for asphalt dosage is 0.1 kg / m³. 2 The minimum unit for fiber usage is 5g / m². 2 The parameter combination that satisfies the conditions can be obtained as follows:

[0071] Table 3: Parameter Combinations for Materials with Different Strengths

[0072]

[0073] Material prices will be adjusted according to market conditions. The price of asphalt is tentatively set at 5 yuan / kg, and the price of fiber at 20 yuan / kg. The price per unit area of ​​waterproofing layer material is P = m 沥青 ·p 沥青 +m 纤维 ·p 纤维 Therefore, under the condition of meeting the crack resistance requirements, the asphalt dosage is 1.6 kg / m³. 2 The fiber usage is 60g / m². 2 The lowest cost is for a material combination with 5cm fiber length, with the fiber + asphalt material costing 9.2 yuan / m³. 2 .

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for selecting and designing parameters for a fiber-reinforced asphalt flexible crack-resistant sealing layer, wherein the method is used to quickly determine the material of the waterproof layer, characterized in that... The parameter selection and design method for the fiber-reinforced asphalt flexible crack-resistant sealing layer includes the following steps: S1. Establish a strength prediction model: Combining physical feature design with support vector machine algorithm, by constructing nonlinear coupling features of asphalt content, fiber content and fiber length, a support vector regression model is trained to obtain a prediction model of the tensile strength of the bridge deck waterproof layer under different material combinations. S2. Establish a theoretical model for the waterproofing performance of the bridge deck crack waterproofing layer: Based on the cracking principle of the waterproofing layer and the force balance of the waterproofing layer, the equivalent stress length of the waterproofing layer can be obtained. With respect to the thickness of the waterproof layer and tensile strength The functional relationship between them, and based on the critical crack width of the waterproof layer. and , , Based on the functional relationship between the two, a test beam including a waterproof layer was constructed. A loading test was conducted to cause the test beam to crack and leak water. The critical crack width at which the test beam cracked and leaked water was measured. The performance of the waterproofing layers was calculated by conducting performance tests on test beams with multiple waterproofing layers of different material combinations. , , Value, the , , The coefficient for the waterproof performance of the waterproof layer is K, where K is the allowable elongation of the waterproof layer. This refers to the "waterproofing layer thickness gain coefficient," which indicates how much the waterproofing performance of the waterproofing layer improves as its thickness increases. It is expressed as an index of the deformation of a material during the tensile process, and it reflects the deformation characteristics of the material during the tensile process; S3. Design of bridge deck waterproofing layer: Based on the crack width of the bridge deck, combined with the prediction model of the tensile strength of the bridge deck waterproofing layer, the theoretical model of the waterproofing performance of the bridge deck crack waterproofing layer, and economic considerations, the material combination of the waterproofing layer is selected.

2. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 1, characterized in that, The predictive model for obtaining the tensile strength of the bridge deck waterproofing layer under different material combinations in step S1 includes the following steps: S101. Based on engineering experience and the requirements of bridge deck waterproofing layer specifications, predict the range of asphalt usage, fiber usage, and fiber length. S102. Using orthogonal design, specimens with different material combinations are prepared and tensile property tests are conducted on the specimens to obtain the tensile force and tensile strength of the specimens. Based on the characteristics of the changes in the combined materials in the specimens with different material combinations, characteristic functions including the variation laws of various parameters are derived. , , ,in Let be the characteristic function of asphalt usage. The characteristic function of fiber usage The characteristic function of fiber length; S103, will , , Tensile strength is used as an input feature in the support vector regression model. To obtain the tensile strength of the bridge deck waterproofing layer under different combinations, learning and prediction are performed to output features. .

3. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 2, characterized in that, Assuming the asphalt usage is kg / m 2 For A, the amount of glass fiber used is in g / m 2 Let G be the length of the glass fiber (cm) and L be the length of the glass fiber. , , ; in In the characteristic function The fiber / asphalt ratio reflects the density of the fiber filler. Parameters for controlling the effect of fiber usage on the rate; This is a constant, reflecting the weight of the influence of asphalt content on fiber content; Fiber length; For optimal fiber length; Parameters used to control the effect of fiber length on the rate.

4. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 3, characterized in that, When the amount of fiber used At that time, all waterproof layers were made of asphalt, and the tensile strength of the waterproof layer was... fixed .

5. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 1, characterized in that, The allowable stretch of the waterproof layer of the same thickness and length They are all the same, that is, when the length is The waterproof layer is stretched to Waterproofing fails at times.

6. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 5, characterized in that, The stress calculation for the waterproof layer including the fibers is as follows: For ease of calculation, we take the unit width as the unit. The stress balance of the waterproof layer can be used to determine... ,and The axial tensile force of the waterproof layer, i.e. ; Therefore ,Right now ,in The thickness of the waterproof layer , , The mass of asphalt and fiber of the waterproof layer per unit area; This refers to the tensile strength of the waterproof layer; ρ represents the ultimate shear stress of the waterproof layer. 沥青 ρ 纤维 These are the asphalt density and fiber density of the waterproof layer, respectively.

7. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 6, characterized in that, When the waterproofing layer fails due to water seepage, the tensile length of the waterproofing layer is equal to the width of the crack in the bridge deck, and the critical crack width of the waterproofing layer is... ,make ,but .

8. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 7, characterized in that, When selecting the material combination for the waterproof layer in step S3, when If the material combination of the waterproof layer is considered to meet the waterproof requirements, then... For safety reasons, Cracks are allowed in the structural design.

9. The method for selecting and designing parameters for fiber-reinforced asphalt flexible crack-resistant sealing layer according to claim 8, characterized in that, Based on the material combination of the waterproof layer that meets the waterproofing requirements, the economically optimal solution for the material combination of the waterproof layer per unit area is selected, and the material price of the waterproof layer per unit area is... ,in , These are the unit price per unit area for asphalt and the unit price per unit area for fiber, respectively.

Images