Design method of building foundation anti-frost heaving system, storage medium and equipment

Abstract

The building foundation anti-frost heaving system design method, storage medium and equipment belong to the technical field of building. In order to solve the problem that there is no anti-frost heaving system design method at present and it is completely dependent on experience, the present application firstly calculates the stress sigma of the ground beam after the anti-frost heaving system is applied based on the safety of the anti-frost heaving system, and obtains the evaluation index mu1 based on the stress of the ground beam after the anti-frost heaving system is applied; the cost and carbon emission of the anti-frost heaving material of each layer of the anti-frost heaving system are calculated based on the anti-frost heaving material of each layer of the anti-frost heaving system, and the economic evaluation index mu2 and the environmental evaluation index mu3 are obtained; the total evaluation parameter delta of the anti-frost heaving system is determined based on the evaluation parameters of the three indexes, and the delta is calculated for the thickness of each material layer in the anti-frost heaving system; the thickness of each material layer is changed, and the delta is iteratively calculated again; if the current delta is greater than the previous delta, the current delta is retained, if the current delta value is reduced, the random change is continued, and until the change amount of the delta is less than or equal to the threshold value, at this time the thickness of each layer of the anti-frost heaving system is the optimal design thickness.

Description

Technical field:

[0001] The present invention belongs to the field of building technology, and in particular relates to an optimization design method, storage medium and equipment for a building foundation anti-freeze heave system. Background technology:

[0002] A ground beam is a closed structure connected to the foundation. Together with structural columns, it forms a seismic crack-limiting system, mitigating uneven settlement. Uneven frost heave deformation of the soil is a key factor in ground beam failure in cold regions. Therefore, to prevent damage to the ground beam caused by frost heave deformation, a frost heave prevention system is required for the ground in contact with the ground beam. However, the design of frost heave prevention systems is currently based solely on field experience. Materials such as fine sand and polystyrene boards are laid to absorb frost heave deformation. However, there is no scientific guidance on the thickness of these frost heave-absorbing materials, making it difficult to scientifically calculate and predict the frost heave deformation absorption effect of frost heave prevention systems. Consequently, problems often arise, such as excessive deformation of the installed frost heave materials making them unreusable and limiting their frost heave absorption effect. Alternatively, the installed frost heave materials are too thick, increasing construction costs and difficulty. Furthermore, design based on experience fails to comprehensively optimize the multiple factors of frost heave deformation absorption, ecological benefits, and economic costs, making it difficult to comprehensively consider all aspects and arrive at an optimal new design for the frost heave prevention system. Summary of the invention:

[0003] In order to solve the problems in the background technology, the present invention proposes a design method for a building foundation anti-frost heave system.

[0004] A design method for a building foundation anti-frost heave system is provided, which is designed for a layered structure anti-frost heave system and includes the following steps:

[0005] S1. Based on the safety of the anti-frost heave system, calculate the stress σ on the ground beam after the anti-frost heave system is applied:

[0006] Existence E i ·l i ≥F i

[0007] Where, E i 、F i is the elastic modulus and elastic limit of different materials, l i is the strain of the i-th layer of anti-frost heave material; S, α, and D are the stress of the ground beam caused by the frost heave of the local frozen soil, the deformation rate of the frozen soil, and the depth of the frozen soil, respectively; ΣL i is the total thickness of the frost heave protection system, E j is the elastic modulus of the jth anti-frost heave material that has not reached its elastic limit; L i is the thickness of the i-th layer of anti-frost heave material; L jis the thickness of the jth anti-frost heave material that has not reached its elastic limit; l nmax is the maximum elastic strain value of the nth anti-frost heave material that reaches its elastic limit, L n is the thickness of the nth type of anti-frost heave material that reaches its elastic limit;

[0008] Then, based on the stress on the ground beam after the anti-frost heave system is applied, the stress evaluation index μ1 is obtained:

[0009]

[0010] Where S is the stress of the ground beam caused by the frost heave of the frozen soil at the construction site;

[0011] S2. Calculate the cost and carbon emissions of the anti-frost heave materials based on the anti-frost heave materials of each layer of the anti-frost heave system, and obtain the economic evaluation index μ2 and environmental evaluation index μ3:

[0012]

[0013] Among them, Cost and Carbon are the corresponding economic cost and carbon emissions of each design solution; Cost max 、Carbon max are the theoretical maximum economic cost and maximum carbon emission of the anti-frost heave system under the boundary conditions of thickness design;

[0014] S3. Determine the total evaluation parameter δ of the anti-frost heave system based on the evaluation parameters of the three indicators:

[0015]

[0016] Where k1, k2 and k3 are the weight coefficients of frost heave reduction effect, total material cost and carbon emission;

[0017] Then randomly input the thickness of each material layer and solve the following equations to find the specific value of σ at this time;

[0018]

[0019] Based on the specific value of σ solved at this time, if there is σ>F i , it is considered that some materials of the anti-frost heave system exceed the elastic limit, and E i ·l i ≥F i The corresponding σ formula is used to solve the stress evaluation index μ1 and the corresponding comprehensive evaluation index δ of the anti-frost heave system; otherwise, select E i ·l i <F iThe corresponding σ formula is used to solve the stress evaluation index μ1 and the corresponding comprehensive evaluation index δ of the anti-frost heave system. Then, the thickness of each material layer is changed, and δ is iteratively calculated again in the same way. The change in δ value is compared. If the current δ is greater than the previous δ, the current δ is retained. If the current δ value decreases, the random change continues until the minimum number of repetitions exceeds and the change in δ is less than or equal to the change threshold. At this time, the thickness of each layer of the corresponding anti-frost heave system is the optimal design thickness.

[0020] Preferably, the change threshold is 0.001.

[0021] Preferably, the total thickness of the anti-frost heave system ΣL i ≤0.5m.

[0022] Preferably, the design process of the stress σ of the ground beam after applying the anti-frost heave system comprises the following steps:

[0023] For the frost heave protection system, there are two deformation situations:

[0024] Each anti-frost heave material should be in a completely elastic state during frost heaving, and can return to its initial state when the frozen soil thaws. When the frozen soil heaves in winter, the sum of the deformations of each layer of anti-frost heave material should be the frost heave deformation of the frozen soil. Taking the anti-frost heave structure as the research object, each layer of anti-frost heave material is regarded as a linear elastic structure. When the material is in the elastic stage, the force exerted on each layer of anti-frost heave material is equal to the frost heave stress exerted on the ground beam. According to Hooke's law, the frost heave stress exerted on the ground beam is equal to the product of the strain of any anti-frost heave material and the elastic modulus:

[0025] ΣΔL i =Σ(L i ·l i )=L=α·(D-ΣL i )

[0026] σ=E1l1=E2l2=E3l3=…

[0027] At this time E i ·l i ≤F i or l i ≤l imax

[0028] Where, ΔL i is the deformation size of the i-th layer of anti-frost heave material, L i 、l i are the thickness and strain of the i-th layer of anti-frost heave material respectively; L is the frost heave deformation of frozen soil, which is represented by the product of the frost heave deformation rate and the frozen soil depth; ΣL i is the total thickness of the frost heave prevention system, α is the frozen soil frost heave deformation rate, and D is the frozen soil depth at the construction site; Ei is the elastic modulus of the i-th layer of anti-frost heave material, F i 、l imax are the elastic limit and maximum strain value of the frost heave protection material of the i-th layer, F i =E i ·l imax ;

[0029] When the stress on a certain anti-frost heave material exceeds the elastic limit of the anti-frost heave material, it is considered that the anti-frost heave material cannot completely absorb the frozen soil frost heave deformation. In this case, the frozen soil frost heave deformation is divided into two parts: one is the deformation absorbed by the anti-frost heave system, and the other is the deformation not absorbed by the anti-frost heave system.

[0030] The total deformation absorbed by the frost heave protection system is:

[0031] ΔL=ΔL1+ΔL2+ΔL3

[0032] Where ΔL is the total deformation absorbed by the frost heave protection system, ΔL1 is the frost heave deformation reduced by the frost heave protection system due to the reduction of frozen soil depth, ΔL1 = α·∑L i ,∑L i is the total thickness of the anti-frost heave system; ΔL2 is the frozen soil frost heave deformation absorbed by the anti-frost heave material without exceeding the elastic limit. E j is the elastic modulus of the jth anti-frost heave material that has not reached its elastic limit, L j is the thickness of the jth anti-frost heave material that has not reached its elastic limit; ΔL3 is the deformation absorbed by the anti-frost heave material due to reaching its elastic limit, ΔL3 = ∑l nmax L n , l nmax is the maximum elastic strain of the nth anti-frost heave material that reaches its elastic limit, L n is the thickness of the nth type of anti-frost heave material that reaches its elastic limit;

[0033] Thus, the total deformation ΔL absorbed by the anti-frost heave system is obtained:

[0034]

[0035] The frost heave stress on the ground beam is calculated based on the proportion of unabsorbed frozen soil frost heave deformation. That is, it is assumed that the ratio of the stress on the ground beam after the frost heave protection system is applied to the stress on the ground beam without the frost heave protection system is equal to the ratio of the unabsorbed frost heave deformation to the initial frost heave deformation; that is:

[0036]

[0037] Among them, α·D is the frost heave deformation of the frozen soil in the construction area;

[0038] Therefore, the stress on the ground beam is expressed by the following formula:

[0039]

[0040] Substituting ΔL into σ, we can get the stress σ on the ground beam:

[0041]

[0042] After simplification:

[0043]

[0044] At this time, there is E i ·l i ≥F i or l i ≥l imax ;

[0045] The final stress of the ground beam is:

[0046] Existence E i ·l i ≥F i .

[0047] Preferably, the economic cost corresponding to each design solution is as follows:

[0048] Cost=∑Cost i ·V i

[0049] V i =L i ·A

[0050] In the formula, Cost i is the total cost per cubic meter of the frost heave protection system materials for the i-th layer; V i is the volume of the material of the i-th layer anti-frost heave system; L i is the thickness of each layer of material, and A is the contact area between the ground beam and the ground.

[0051] Preferably, the total cost per cubic meter of the anti-freeze heaving system material of the i-th layer is i as follows:

[0052] Cost i =m i +h i

[0053] Where m i h is the purchase cost per cubic meter of the material for the i-th layer anti-frost heave system; i is the construction cost per cubic meter of the i-th layer of anti-frost heave material.

[0054] Preferably, the carbon emissions Carbon corresponding to each design solution are as follows:

[0055] Carbon=∑Carbon i ·V i

[0056] In the formula, Carbon i is the total carbon emissions per cubic meter of the i-th layer of anti-frost heave system materials.

[0057] Preferably, the total carbon emissions per cubic meter of the i-th layer of anti-freeze heave system material is i as follows:

[0058] Carbon i =a i +b i ·d+c i

[0059] Where a i is the total carbon emission per cubic meter of the frost heave protection system material of the i-th layer, b i is the total carbon emission per cubic meter of the i-th layer anti-freeze system material per kilometer of transportation, d is the transportation distance, c i is the total carbon emission per cubic meter of the i-th layer of frost heave protection system material.

[0060] A computer storage medium stores at least one instruction, which is loaded and executed by a processor to implement a design method for a building foundation anti-frost heave system.

[0061] A building foundation anti-frost heave system design device comprises a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a building foundation anti-frost heave system design method.

[0062] Beneficial effects:

[0063] In response to the lack of existing anti-frost heave system design methods, the present invention takes into account three factors: frost heave deformation absorption effect, ecological benefits and economic costs. It combines the elastic-plastic parameters of the anti-frost heave material itself, the construction cost of the anti-frost heave material per unit volume and carbon emissions to achieve an optimized design of the anti-frost heave system. This allows the anti-frost heave system to effectively absorb frost heave deformation while taking into account economic and ecological benefits, thereby guiding the design of the anti-frost heave system, reducing construction costs and improving ecological benefits.

[0064] Mainly reflected in:

[0065] 1. In view of the lack of existing anti-frost heave system design methods, the present invention designs an effective building foundation anti-frost heave system design method, filling the gap in the ground beam anti-frost heave system design method.

[0066] 2. The anti-frost heave system is designed to comprehensively absorb deformation and reduce frost heave stress, so that the anti-frost heave material can achieve better anti-frost heave effect.

[0067] 3. Taking both cost and ecological benefits into consideration simultaneously, the construction cost and carbon emissions can be designed and evaluated, maximizing both cost and ecological benefits. Description of the drawings:

[0068] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and accompanying drawings.

[0069] Figure 1 Schematic diagram of the anti-frost heave system.

[0070] Figure 2 Schematic diagram of the multi-objective evaluation and optimization design process of the frost heave prevention system. Specific implementation method:

[0071] To make the objectives, technical solutions, and advantages of the present invention more clearly apparent, the present invention is described below using specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0072] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, the accompanying drawings only show structures and / or processing steps that are closely related to the solutions according to the present invention, while other details that are not closely related to the present invention are omitted.

[0073] The present invention proposes an optimization design method for a frost heave prevention system based on three factors: frost heave deformation absorption effect, ecological benefits, and economic costs. By testing the elastic-plastic parameters of frost heave prevention materials at different temperatures, considering theoretical calculations of frozen soil frost heave deformation, and the boundary conditions for matching frozen soil frost heave deformation with the deformation absorption of frost prevention materials, the frost heave prevention system is optimized based on the construction cost and carbon emissions per unit volume of frost heave prevention materials. This method determines the thickness ranges of each material layer in the building foundation frost heave prevention system, ensuring the effectiveness of the frost heave prevention system and reducing costs. The present invention is further described below in conjunction with specific embodiments.

[0074] This embodiment is a design method for a building foundation anti-frost heave system. Figure 1The design of the anti-frost heave system with the layered structure shown in the figure is carried out. The design process includes safety calculation, economic and cost calculation, and multi-index evaluation and optimization. The specific optimization design steps are as follows:

[0075] Step 1: Safety design of anti-frost heave system:

[0076] When designing a frost heave prevention system, the most important thing is to ensure the safety of the building, that is, to ensure that the stress on the building's ground beam is less than its strength design value to avoid frost heave damage. By comparing the changes in the stress on the ground beam after the frost heave prevention system is applied, the safety of the ground beam is evaluated. The overall control equation is:

[0077] σ≤σ max

[0078] Where, σ is the stress on the ground beam, σ max is the design strength value of the ground beam. The stress on the ground beam after applying the anti-frost heave system can be calculated by the following formula:

[0079] Existence E i ·l i ≥F i

[0080] Where, E i 、F i is the elastic modulus and elastic limit of different materials, l i is the strain of the i-th layer of anti-frost heave material; S, α, and D are the stress of the ground beam caused by the frost heave of the local frozen soil, the deformation rate of the frozen soil, and the depth of the frozen soil, respectively; ΣL i is the total thickness of the frost heave protection system, E j is the elastic modulus of the jth anti-frost heave material that has not reached its elastic limit, L j is the thickness of the jth anti-frost heave material that has not reached its elastic limit; L i is the thickness of the i-th layer of anti-frost heave material; l nmax is the maximum elastic strain value of the nth anti-frost heave material that reaches its elastic limit, L n is the thickness of the nth anti-frost heave material that reaches its elastic limit.

[0081] In order to further measure the role of the anti-frost heave system and evaluate its effect, a dimensionless method is proposed to calculate the ratio of the ground beam stress before and after the application of the anti-frost heave system, and obtain the stress evaluation index μ1, as shown in the following formula.

[0082]

[0083] The following is the process of deducing the stress on the ground beam after the anti-frost heave system is applied:

[0084] First determine the elastic modulus E of different materialsi , elastic limit F i , maximum strain value l imax The data provided by the construction site and other parameters such as the stress S of the ground beam caused by frost heave, the deformation rate α of the frost heave, and the depth D of the frozen soil provide data for safety calculations. The boundary conditions and deformation conditions for the thickness design of the anti-frost heave system are then determined.

[0085] For the frost heave protection system, there are two deformation situations:

[0086] 1. The forces on all anti-frost heave materials in the anti-frost heave system are less than the elastic limit. This is an ideal condition. Each anti-frost heave material should be in a completely elastic state when it heaves. When the frozen soil melts, the anti-frost heave material can return to its initial state, ensuring that the anti-frost heave system can be used cyclically under frozen soil freeze-thaw conditions. At this time, when the frozen soil heaves in winter, the sum of the deformations of each layer of anti-frost heave material should be the frozen soil heave deformation. Taking the anti-frost heave structure as the research object, each layer of anti-frost heave material can be regarded as a linear elastic structure. When the material is in the elastic stage, the force on each layer of anti-frost heave material is equal to the frost heave stress on the ground beam. According to Hooke's law, the frost heave stress on the ground beam is equal to the product of the strain of any anti-frost heave material and the elastic modulus:

[0087] ΣΔL i =Σ(Li·l i )=L=α·(D-ΣL i )

[0088] σ=E1l1=E2l2=E3l3=…

[0089] At this time: E i ·l i ≤F i or l i ≤l imax

[0090] Where, ΔL i is the deformation size of the i-th layer of anti-frost heave material, L i 、l i are the thickness and strain of the i-th layer of anti-frost heave material respectively; L is the frost heave deformation of frozen soil, which can be expressed by the product of the frost heave deformation rate and the frozen soil depth; ΣL i is the total thickness of the frost heave prevention system, α is the frozen soil frost heave deformation rate, and D is the frozen soil depth at the construction site; E i is the elastic modulus of the i-th layer of anti-frost heave material, F i 、l imax are the elastic limit and maximum strain value of the frost heave protection material of the i-th layer, F i =E i ·l imax .

[0091] 2. When the stress of the anti-frost heaving material exceeds the elastic limit of the anti-frost heaving material, it can be considered that the anti-frost heaving material cannot completely absorb the frost heaving deformation of the frozen soil. At this time, the frost heaving deformation of the frozen soil can be divided into two parts, one part is the deformation absorbed by the anti-frost heaving system, and the other part is the deformation not absorbed by the anti-frost heaving system. For the deformation absorbed by the anti-frost heaving system, part of the frost heaving deformation is reduced due to the replacement of the frozen soil by the anti-frost heaving material, and since the frost heaving deformation of the material itself in the anti-frost heaving system is very small, after replacing the frozen soil, the depth of the frozen soil is equivalent to reducing the thickness of the anti-frost heaving system, thereby reducing the frost heaving deformation of the frozen soil (for example, the local frozen soil depth in Heihe is 3m, and the total thickness of the anti-frost heaving system is 0.5m, at this time the actual thickness of the frozen soil should be calculated as 2.5m, that is, the part of the anti-frost heaving system laid does not count into the depth of the frozen soil). In addition, the anti-frost heaving system also absorbs part of the frost heaving deformation due to its own stress deformation, at this time part of the anti-frost heaving material reaches the elastic limit, and the deformation absorbed by it is considered to be the product of the maximum strain value and its thickness, that is, the maximum elastic deformation; the deformation of other anti-frost heaving materials still in the elastic stage is calculated according to Hooke's law. Therefore, the total deformation absorbed by the anti-frost heaving system is:

[0092] ΔL = ΔL1 + ΔL2 + ΔL3

[0093] Wherein, ΔL is the total deformation absorbed by the anti-frost heaving system, ΔL1 is the frost heaving deformation of the frozen soil reduced by the anti-frost heaving system, ΔL1 = α · ∑L i , ∑L i is the total thickness of the anti-frost heaving system; ΔL2 is the frost heaving deformation of the frozen soil absorbed by the anti-frost heaving material without exceeding the elastic limit, E j is the elastic modulus of the jth anti-frost heaving material that does not reach the elastic limit, L j is the thickness of the jth anti-frost heaving material that does not reach the elastic limit; ΔL3 is the deformation absorbed by the anti-frost heaving material due to reaching the elastic limit, at this time, although the anti-frost heaving material will continue to deform and further reduce the frost heaving deformation, generally speaking, due to the limited deformation capacity of the anti-frost heaving material at this time, in order to ensure the safety of the ground beam, it can be approximately considered that the frost heaving deformation absorbed at this time is only equal to the deformation of the anti-frost heaving material when it reaches the elastic limit, that is, ΔL3 = Σl nmax L n , l nmax is the maximum elastic strain of the nth anti-frost heaving material that reaches the elastic limit, L n is the thickness of the nth anti-frost heaving material that reaches the elastic limit;

[0094] Thus, the total deformation ΔL absorbed by the anti-frost heaving system can be obtained:

[0095]

[0096] In this case, the frost heave stress on the ground beam can be calculated based on the proportion of unabsorbed frozen soil frost heave deformation, that is, the ratio of the stress on the ground beam after the frost heave protection system is applied to the stress on the ground beam without the frost heave protection system and the ratio of the unabsorbed frost heave deformation to the initial frost heave deformation are equal. That is:

[0097]

[0098] α·D is the frost heave deformation of the frozen soil at the construction site.

[0099] Therefore, the stress on the ground beam can be expressed by the following formula:

[0100]

[0101] Substituting ΔL into the equation, we can get the stress σ on the ground beam:

[0102]

[0103] After simplification:

[0104]

[0105] At this time, there is E i ·l i >F i or l i >l imax

[0106] In summary, the stress on the ground beam can be calculated by the following formula:

[0107]

[0108] Step 2: Cost design of anti-frost heave system:

[0109] In actual engineering, while ensuring safety, it is also necessary to strictly control economic and environmental costs (i.e., carbon emissions). Therefore, it is necessary to design and calculate the total economic cost and carbon emissions per cubic meter of the frost heave prevention system, and conduct a comprehensive evaluation of the economic and environmental costs of the frost heave prevention system to maximize economic and ecological benefits. The implementation process is as follows:

[0110] For the anti-frost heave system, under the boundary conditions of thickness design, there is a theoretical maximum economic cost of the anti-frost heave system. max and the maximum carbon emissions max Similar to the safety design, the dimensionless method is used to calculate the economic cost and carbon emissions of each solution and the theoretical maximum economic cost. max and the maximum carbon emissions maxThe ratio between them is made to obtain the economic evaluation index μ2 and the environmental evaluation index μ3, as shown in the following formula.

[0111]

[0112] The economic cost and carbon emissions of each design solution are calculated by summing the cost and carbon emissions of each anti-frost heave material, as shown in the following formula:

[0113]

[0114] In the formula, Cost i is the total cost per cubic meter of the frost heave system material of the i-th layer; m i h is the purchase cost per cubic meter of the material for the i-th layer anti-frost heave system; i is the construction cost per cubic meter of the i-th layer of anti-frost heave material; V i is the volume of the material of the i-th layer anti-frost heave system; L i is the thickness of each layer of material, and A is the contact area between the ground beam and the ground.

[0115]

[0116] In the formula, Carbon i is the total carbon emission per cubic meter of the i-th layer anti-frost heave system material, a i is the total carbon emission per cubic meter of the frost heave protection system material of the i-th layer, b i is the total carbon emission per cubic meter of the i-th layer anti-freeze system material per kilometer of transportation, d is the transportation distance, c i V is the total carbon emission per cubic meter of the frost heave protection system material of the i-th layer; i is the material volume of the i-th layer anti-frost heave system.

[0117] In fact, there is no requirement for the order of steps 1 and 2 of the present invention. The relevant calculations of step 2 can be performed first, and then the calculations of step 1; or they can be performed simultaneously.

[0118] Step 3: Multi-objective evaluation and optimization design method of frost heave prevention system:

[0119] Through steps 1 and 2, the evaluation parameters for the safety, economic cost, and environmental cost of the frost heave prevention system were obtained. To further couple these three factors, coordinately optimize the safety, economic cost, and environmental cost of the frost heave prevention system and achieve a comprehensive design of the three indicators, the Euclidean distance concept was used to comprehensively evaluate the evaluation parameters of the three indicators and determine the overall evaluation parameter δ of the frost heave prevention system.

[0120] Because the theoretical maximum value of a single indicator's evaluation parameter is 1, the distance between (μ1, μ2, μ3) and (1, 1, 1) is calculated. The larger the distance, the greater the difference between the current solution and the theoretical maximum value, and the closer it is to the ideal value. To highlight the importance of a certain indicator, a weight coefficient is introduced to amplify or mask the impact of a certain evaluation parameter on the optimization design process. The anti-frost heave system can be evaluated according to this formula:

[0121]

[0122] Where k1, k2, and k3 are weight coefficients for frost heave reduction, total material cost, and carbon emissions, and are generally between 0 and 1. Based on actual needs, a larger weight coefficient may be used to highlight the importance of a certain factor in the design.

[0123] According to the actual construction requirements, after determining the weight coefficients k1, k2 and k3, combined with Figure 2 To illustrate this process, the thickness of each material layer is randomly input. At this time, the first step is to determine whether the anti-frost heave system is in the elastic stage, that is, by solving the equations simultaneously:

[0124]

[0125] Find the specific value of σ at this time. If there exists σ>F i , it is considered that part of the material of the anti-frost heave system exceeds the elastic limit at this time, and the inelastic section σ formula is used to solve the comprehensive evaluation index of the anti-frost heave system. Otherwise, the elastic section σ formula is selected to solve the comprehensive evaluation index of the anti-frost heave system; then, δ is calculated; then, a small random change is added to the randomly input material layer thickness, and δ is iteratively calculated again. The change in δ value is compared. If the current δ is greater than the previous δ, the current δ is retained; if the current δ value decreases, the random change is continued; repeat for more than 1000 times and δ does not change significantly. If δ does not change significantly, the change in δ is less than or equal to the set change threshold. The change threshold in this embodiment is 0.001.

[0126] At this time, the thickness of each layer of the corresponding anti-frost heave system is the optimal design thickness.

[0127] Obtain the thickness of each layer of the anti-frost heave system at this time and complete the optimization design of the anti-frost heave system.

[0128] Example 1:

[0129] During the construction of the factory building in Heihe area, slag and polystyrene board were used as anti-freeze heave materials to design the anti-freeze heave system. After testing, the elastic modulus of slag and polystyrene board were 15000MPa and 3MPa respectively, the maximum strain of polystyrene board was 0.1, F i =E i ·l imax=3×0.1=0.3MPa; the total carbon emissions per cubic meter are 0.06 tons and 0.24 tons, respectively, and the total construction costs per cubic meter are 70 yuan and 200 yuan, respectively. Without the frost heave prevention system, the frozen soil exerts a pressure S = 35MPa on the ground beam, the frozen soil frost heave deformation is L = 5cm, and the frozen soil frost heave deformation rate is 2%. The structure of this double-layer frost heave prevention system was designed, with the frost heave effect as the optimal consideration. k1, k2, and k3 were set to 1, 0.5, and 0.5, respectively, to optimize the frost heave prevention system.

[0130] Among them, the contact area between the anti-freeze heave system and the ground beam is ignored (that is, the contact area is set to 1, and the volume of the material of the i-th layer anti-freeze heave system V is i You can directly use the thickness L i (expressed), the theoretical maximum construction cost per square meter of the anti-frost heave system is obtained when the total thickness of the anti-frost heave system does not exceed 0.5m. In this case, the cost and carbon emissions required for 0.5m polystyrene board are obtained. After calculation,

[0131] Cost max =200×0.5=100 yuan / m 2

[0132] Carbon max =0.24×0.5=0.12 tons / m 2

[0133] Cost = 200 × L1 + 70 × L2

[0134] Carbon=0.24×L1+0.06×L2

[0135] There are two cases for stress calculation of frost heave protection system:

[0136] (1) When the frost heave deformation of frozen soil can be completely absorbed by the elastic deformation of the anti-frost heave material:

[0137] σ=3·l1=15000·l2

[0138] When the elastic deformation can be completely absorbed, the stress on the polystyrene board (that is, the stress on the ring beam) does not exceed its elastic limit, that is, σ≤F i ; In this case, the frost heave deformation of the frozen soil is completely absorbed, so

[0139] l1·L1+l2·L2=0.05-0.02(L1+L2)

[0140] By solving the equations simultaneously, the calculation formula of the stress on the elastic section beam is obtained, namely:

[0141]

[0142] (2) When the frost heave deformation of frozen soil cannot be completely absorbed by the elastic deformation of the anti-frost heave material:

[0143]

[0144] At this time, the stress on the polystyrene board (that is, the stress on the ring beam) exceeds its elastic limit, that is, σ>F i ;

[0145] The stress evaluation index is calculated for two cases respectively:

[0146] (1) When σ≤F i =0.3MPa:

[0147]

[0148] (2) When σ>F i =0.3MPa:

[0149]

[0150] Then calculate the economic evaluation index μ2 and the environmental evaluation index μ3:

[0151]

[0152] For the two cases, the comprehensive evaluation index of the anti-frost heave system is obtained according to the required weights:

[0153] (1) When σ≤0.3MPa:

[0154]

[0155] (2) When σ>0.3MPa:

[0156]

[0157] First, randomly generate the thickness of the anti-frost heave system (0.2, 0.2), that is, the slag thickness is 0.2m, the polystyrene board thickness is 0.2m, and substitute it into the elastic section ground beam stress calculation formula to calculate It is judged that 0.720MPa>0.3MPa; therefore, it is in the inelastic section at this time, and the comprehensive evaluation index of the anti-frost heave system is selected from formula (2), namely:

[0158]

[0159] After obtaining the current comprehensive evaluation index, the thickness is changed, for example, to (0.25, 0.25), and the stress calculation formula of the elastic section beam is still substituted into it. It is judged that 0.360MPa>0.3MPa; therefore, it is in the inelastic section at this time, and the comprehensive evaluation index of the anti-frost heave system is selected from formula (2), namely:

[0160]

[0161] If the stress calculation formula of the elastic section ground beam is σ≤0.3MPa, the comprehensive evaluation index of the anti-frost heave system of formula (1) is selected;

[0162] After recalculating the comprehensive evaluation index, if the evaluation index increases compared with the index before the change, it will be retained; if it decreases, the above process will be repeated until the evaluation index has no obvious change.

[0163] After optimization, when the slag thickness is 0.2m and the polystyrene board thickness is 0.3m, the comprehensive evaluation index is the largest and the stress is 7.3MPa, which is greatly reduced compared with the stress before protection.

[0164] It should be noted that: when calculating the i =0.3MPa for comparison, the stress calculation formula of the elastic section beam is used for calculation, that is, Calculate; in conjunction with F i After making the size judgment, the comprehensive evaluation index of the anti-frost heave system is calculated based on the actual i Calculate δ for the specific case in the two cases.

[0165] Example 2:

[0166] During the construction of a key project in a certain area of ​​Hebei Province, slag and polystyrene boards were used as anti-freeze heave materials to design an anti-freeze heave system. After testing, the elastic modulus of polystyrene boards and slag were 15000MPa and 3MPa respectively, the maximum strain of polystyrene boards was 0.1, and F i =E i ·l imax = 3 × 0.1 = 0.3 MPa; the total carbon emissions per cubic meter are 0.06 tons and 0.24 tons, respectively, and the total construction costs per cubic meter are 70 yuan and 200 yuan, respectively. Without the frost heave prevention system, the frozen soil will exert a pressure S = 32 MPa on the ground beam, the frozen soil frost heave deformation is L = 4 cm, and the frozen soil frost heave deformation rate is 2%. The structure of the double-layer frost heave prevention system was designed, with the frost heave effect as the optimal consideration. k1, k2, and k3 were set to 1, 0.1, and 0.1, respectively, to optimize the frost heave prevention system.

[0167] Among them, ignoring the contact area between the anti-frost heave system and the ground beam, the theoretical maximum construction cost per square meter of the anti-frost heave system is obtained when the total thickness of the anti-frost heave system does not exceed 0.5m. In this case, the cost and carbon emissions required for 0.5m polystyrene board are calculated.

[0168] Cost max = 200 x 0.5 = 100 yuan / m 2

[0169] Carbon max = 0.24 x 0.5 = 0.12 tons / m 2

[0170] Cost = 200 x L1 + 70 x L2

[0171] Carbon = 0.24 x L1 + 0.06 x L2

[0172] For stress calculation of anti-frost heaving system, there are two cases:

[0173] (1) When the frost heaving deformation of frozen soil can be completely absorbed by the elastic deformation of anti-frost heaving material:

[0174] σ = 3 x l1 = 15000 x l2

[0175] When the elastic deformation can be completely absorbed, the stress on the polystyrene board (i.e. the stress on the ring beam) does not exceed its elastic limit, i.e. σ ≤ F i ; Since in this case the frost heaving deformation of frozen soil is completely absorbed, there is

[0176] l1 x L1 + l2 x L2 = 0.04 - 0.02 (L1 + L2)

[0177] By solving the equation set, the stress calculation formula of the elastic section of the ground beam is obtained, i.e.

[0178]

[0179] (2) When the frost heaving deformation of frozen soil cannot be completely absorbed by the elastic deformation of anti-frost heaving material:

[0180]

[0181] At this time, the stress on the polystyrene board (i.e. the stress on the ring beam) exceeds its elastic limit, i.e. σ > F i ;

[0182] The stress evaluation index is calculated for the two cases respectively:

[0183] (1) When σ ≤ 0.3 MPa:

[0184]

[0185] (2) When σ > 0.3 MPa:

[0186]

[0187] Then the economic evaluation index μ2 and the environmental evaluation index μ3 are calculated:

[0188]

[0189] For the two cases, the anti-frost heaving system comprehensive evaluation index is calculated according to the required weight respectively:

[0190] (1) When σ≤0.3MPa:

[0191]

[0192] (2) When σ>0.3MPa:

[0193]

[0194] First, randomly generate the thickness of the anti-frost heaving system (0.2, 0.2), that is, the slag thickness is 0.2m and the polystyrene board thickness is 0.2m, which is substituted into the elastic section ground beam stress calculation formula to calculate Determine that 0.630MPa>0.3MPa; therefore, at this time, it is in the non-elastic section, and the formula (2) anti-frost heaving system comprehensive evaluation index is selected, that is:

[0195]

[0196] The current comprehensive evaluation index can be obtained, and then the thickness is changed, for example, to (0.25, 0.25), which is still substituted into the elastic section ground beam stress calculation formula to calculate Determine that 0.600MPa>0.3MPa; therefore, at this time, it is in the non-elastic section, and the formula (2) anti-frost heaving system comprehensive evaluation index is selected, that is:

[0197]

[0198] If the elastic section ground beam stress calculation formula calculates σ≤0.3MPa, the formula (1) anti-frost heaving system comprehensive evaluation index is selected;

[0199] After the comprehensive evaluation index is calculated again, if the evaluation index increases compared with the index before the change, it is retained; if it decreases, the above process is repeated until the evaluation index has no obvious change.

[0200] After optimization, when the slag thickness is 0m and the polystyrene board thickness is 0.5m, the comprehensive evaluation index is the largest at this time, the stress is 0.24MPa, which is greatly reduced compared with the stress before protection, and the circle beam is almost not affected by the frost heaving stress, at this time, the cost per square meter increases by 100 yuan. Specific implementation method two:

[0202] The embodiment is a computer storage medium, and the computer storage medium stores at least one instruction, and the at least one instruction is loaded and executed by a processor to implement a building foundation anti-frost heaving system design method.

[0203] The computer storage medium of the embodiment includes but is not limited to the storage medium, an optical storage medium. Specific implementation three:

[0205] The embodiment is a building foundation anti-frost heaving system design device, and the device includes a processor and a memory, and the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a building foundation anti-frost heaving system design method.

[0206] The device of the embodiment includes but is not limited to the processor and the memory, and can also include an interaction and display component, etc.

[0207] The basic principles and main features of the present application and the advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A design method for a building foundation anti-frost heave system, characterized in that: The design of the anti-frost heave system for layered structures includes the following steps: S1. Based on the safety of the anti-frost heave system, calculate the stress σ on the ground beam after the anti-frost heave system is applied: Where, E i 、F i is the elastic modulus and elastic limit of different materials, l i is the strain of the i-th layer of anti-frost heave material; S, α, and D are the stress of the ground beam caused by the frost heave of the local frozen soil, the deformation rate of the frozen soil, and the depth of the frozen soil, respectively; ΣL i is the total thickness of the frost heave protection system, E j is the elastic modulus of the jth anti-frost heave material that has not reached its elastic limit, L j is the thickness of the jth anti-frost heave material that has not reached its elastic limit; L i is the thickness of the i-th layer of anti-frost heave material; l nmax is the maximum elastic strain value of the nth anti-frost heave material that reaches its elastic limit, L n is the thickness of the nth type of anti-frost heave material that reaches its elastic limit; Then, based on the stress on the ground beam after the anti-frost heave system is applied, the stress evaluation index μ1 is obtained: Where S is the stress of the ground beam caused by the frost heave of the frozen soil at the construction site; S2. Calculate the cost and carbon emissions of the anti-frost heave materials based on the anti-frost heave materials of each layer of the anti-frost heave system, and obtain the economic evaluation index μ2 and environmental evaluation index μ3: Among them, Cost and Carbon are the corresponding economic cost and carbon emissions of each design solution; Cost max 、Carbon max are the theoretical maximum economic cost and maximum carbon emission of the anti-frost heave system under the boundary conditions of thickness design; S3. Determine the total evaluation parameter δ of the anti-frost heave system based on the evaluation parameters of the three indicators: Where k1, k2 and k3 are the weight coefficients of frost heave reduction effect, total material cost and carbon emission; Then randomly input the thickness of each material layer and solve the following equations to find the specific value of σ at this time; Based on the specific value of σ solved at this time, if there is σ>F i , it is considered that some materials of the anti-frost heave system exceed the elastic limit, and E i ·l i ≥F i The corresponding σ formula is used to solve the stress evaluation index μ1 and the corresponding comprehensive evaluation index δ of the anti-frost heave system; otherwise, select E i ·l i <F i The corresponding σ formula is used to solve the stress evaluation index μ1 and the corresponding comprehensive evaluation index δ of the anti-frost heave system. Then, the thickness of each material layer is changed, and δ is iteratively calculated again in the same way. The change in δ value is compared. If the current δ is greater than the previous δ, the current δ is retained. If the current δ value decreases, the random change continues until the minimum number of repetitions exceeds and the change in δ is less than or equal to the change threshold. At this time, the thickness of each layer of the corresponding anti-frost heave system is the optimal design thickness.

2. A building foundation anti-frost heave system design method according to claim 1, characterized in that: The change threshold is 0.

001.

3. The design method of a building foundation anti-frost heave system according to claim 1, characterized in that: The total thickness of the anti-frost heave system ΣL i ≤0.5m.

4. A building foundation anti-frost heave system design method according to claim 3, characterized in that: The design process of the stress σ of the ground beam after applying the anti-frost heave system includes the following steps: For the frost heave protection system, there are two deformation situations: Each anti-frost heave material should be in a completely elastic state during frost heaving, and can return to its initial state when the frozen soil thaws. When the frozen soil heaves in winter, the sum of the deformations of each layer of anti-frost heave material should be the frost heave deformation of the frozen soil. Taking the anti-frost heave structure as the research object, each layer of anti-frost heave material is regarded as a linear elastic structure. When the material is in the elastic stage, the force exerted on each layer of anti-frost heave material is equal to the frost heave stress exerted on the ground beam. According to Hooke's law, the frost heave stress exerted on the ground beam is equal to the product of the strain of any anti-frost heave material and the elastic modulus: SDL i =Σ(L i ·l i )=L=α·(D-ΣL i ) σ=E1l1=E2l2=E3l3=… At this time E i ·l i <F i or l i <l imax Where, ΔL i is the deformation size of the i-th layer of anti-frost heave material, L i 、l i are the thickness and strain of the i-th layer of anti-frost heave material respectively; L is the frost heave deformation of frozen soil, which is represented by the product of the frost heave deformation rate and the frozen soil depth; ΣL i is the total thickness of the frost heave prevention system, α is the frozen soil frost heave deformation rate, and D is the frozen soil depth at the construction site; E i is the elastic modulus of the i-th layer of anti-frost heave material, F i 、l imax are the elastic limit and maximum elastic strain value of the i-th layer of anti-frost heave material respectively; When the stress on a certain anti-frost heave material exceeds the elastic limit of the anti-frost heave material, it is considered that the anti-frost heave material cannot completely absorb the frozen soil frost heave deformation. In this case, the frozen soil frost heave deformation is divided into two parts: one is the deformation absorbed by the anti-frost heave system, and the other is the deformation not absorbed by the anti-frost heave system. The total deformation absorbed by the frost heave protection system is: ΔL=ΔL1+ΔL2+ΔL3 Where ΔL is the total deformation absorbed by the frost heave protection system, ΔL1 is the frost heave deformation reduced by the frost heave protection system due to the reduction of frozen soil depth, ΔL1 = α·∑L i ,∑L i is the total thickness of the anti-frost heave system; ΔL2 is the frozen soil frost heave deformation absorbed by the anti-frost heave material without exceeding the elastic limit. E j is the elastic modulus of the jth anti-frost heave material that has not reached its elastic limit, L j is the thickness of the jth anti-frost heave material that has not reached its elastic limit; ΔL3 is the deformation absorbed by the anti-frost heave material due to reaching its elastic limit, ΔL3 = ∑l nmax L n , l nmax is the maximum elastic strain of the nth anti-frost heave material that reaches its elastic limit, L n is the thickness of the nth type of anti-frost heave material that reaches its elastic limit; Thus, the total deformation ΔL absorbed by the anti-frost heave system is obtained: The frost heave stress on the ground beam is calculated based on the proportion of unabsorbed frozen soil frost heave deformation. That is, it is assumed that the ratio of the stress on the ground beam after the frost heave protection system is applied to the stress on the ground beam without the frost heave protection system is equal to the ratio of the unabsorbed frost heave deformation to the initial frost heave deformation; that is: Among them, α·D is the frost heave deformation of the frozen soil in the construction area; Therefore, the stress on the ground beam is expressed by the following formula: Substituting ΔL into σ, we can get the stress σ on the ground beam: After simplification: At this time, there is E i ·l i ≥F i or l i ≥l imax ; The final stress of the ground beam is:

5. A method for designing a building foundation anti-frost heave system according to claim 1, 2, 3 or 4, characterized in that: The corresponding economic costs of each design solution are as follows: Cost=∑Cost i ·V i V i =L i ·A In the formula, Cost i is the total cost per cubic meter of the frost heave protection system materials for the i-th layer; V i is the volume of the material of the i-th layer anti-frost heave system; L i is the thickness of each layer of material, and A is the contact area between the ground beam and the ground.

6. A building foundation anti-frost heave system design method according to claim 5, characterized in that: The total cost per cubic meter of the anti-freeze heave system material of the i-th layer is Cost i as follows: Cost i =m i +h i Where m i h is the purchase cost per cubic meter of the material for the i-th layer anti-frost heave system; i is the construction cost per cubic meter of the i-th layer of anti-frost heave material.

7. A building foundation anti-frost heave system design method according to claim 6, characterized in that: The corresponding carbon emissions of each design solution are as follows: Carbon=∑Carbon i ·V i In the formula, Carbon i is the total carbon emissions per cubic meter of the i-th layer of anti-frost heave system materials.

8. A building foundation anti-frost heave system design method according to claim 7, characterized in that: The total carbon emissions per cubic meter of the i-th layer of anti-freeze heave system materials i as follows: Carbon i =a i +b i ·d+c i Where a i is the total carbon emission per cubic meter of the frost heave protection system material of the i-th layer, b i is the total carbon emission per cubic meter of the i-th layer anti-freeze system material per kilometer of transportation, d is the transportation distance, c i is the total carbon emission per cubic meter of the i-th layer of frost heave protection system material.

9. A computer storage medium, characterized in that The computer storage medium stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a design method for a building foundation anti-frost heave system according to any one of claims 1 to 8.

10. A building foundation anti-frost heave system design device, characterized in that: The device includes a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a design method for a building foundation anti-freeze heave system according to any one of claims 1 to 8.

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