A method for optimizing design of a self-stable foundation pit supporting system

Abstract

The application provides a foundation pit self-stabilizing type supporting system optimization design method, relates to the technical field of foundation pit engineering construction, and specifically comprises the following steps: adopting inclined front bracing piles to replace traditional reinforced concrete horizontal supports to provide resistance and balance the pressure of the soil outside the pit; collecting mechanical parameters and environmental parameters of the foundation pit; performing dimensionless processing on the parameters to generate stress indexes, deformation rates and vibration intensities; calculating a foundation pit stability coefficient according to the generated indexes, and comparing the foundation pit stability coefficient with a preset safety threshold; when an unsafe state is detected, triggering a feedback mechanism to adjust support structure parameters in real time. By adopting inclined front bracing piles to replace traditional reinforced concrete horizontal supports, the application utilizes the inclined front bracing piles to provide resistance, thereby optimizing the stability of the foundation pit supporting structure, reducing the construction period and cost; meanwhile, the application proposes a foundation pit stability coefficient calculation method based on multiple parameters, which can monitor the stability state of the foundation pit in real time.

Description

Technical Field

[0001] This invention relates to the field of foundation pit construction technology, specifically to an optimized design method for a self-stabilizing support system for foundation pits. Background Technology

[0002] In building construction, foundation pit support structures are crucial infrastructure for ensuring the smooth progress of underground engineering projects. Traditional foundation pit support methods primarily employ reinforced concrete horizontal supports. This method can provide sufficient support under relatively simple geological conditions, ensuring the stability of the surrounding soil. However, reinforced concrete horizontal support structures have long construction cycles and require significant materials and manpower, resulting in high construction costs. Furthermore, when the foundation pit construction environment is complex, such as with high groundwater levels or unstable geological conditions, reinforced concrete horizontal support structures often struggle to effectively address these challenges. In situations with severe groundwater seepage, traditional support structures are susceptible to corrosion, further affecting their support effectiveness and service life.

[0003] Existing foundation pit support technologies also have certain shortcomings in monitoring and feedback mechanisms. Traditional monitoring systems mainly rely on single parameters, such as soil pressure or foundation pit deformation, lacking comprehensive consideration of multiple parameters. This single-parameter monitoring method cannot fully reflect the actual stability state of the foundation pit, especially under conditions of variable environmental factors, such as humidity changes, groundwater level fluctuations, and construction vibrations. Furthermore, traditional monitoring systems are mostly offline, unable to achieve real-time data acquisition and processing, resulting in the inability to take timely and effective adjustment measures when anomalies occur in the foundation pit support structure. This delayed adjustment mechanism increases the risk of foundation pit instability, potentially leading to significant safety hazards and economic losses. Therefore, there is an urgent need for an innovative method that can monitor multiple parameters in real time during construction, accurately assess foundation pit stability, and adjust support structure parameters in a timely manner to improve the safety and reliability of foundation pit support.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide an optimized design method for a self-stabilizing support system for foundation pits, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An optimization design method for a self-stabilizing support system for foundation pits, comprising the following steps:

[0008] Step 1: Adopt self-stabilizing foundation pit support structure technology, use inclined forward support piles instead of reinforced concrete horizontal supports, and use the inclined forward support piles to provide resistance and achieve balance with the pressure of the soil outside the pit;

[0009] Step 2: Collect the mechanical and environmental parameters of the foundation pit. The mechanical parameters are soil pressure, foundation pit deformation, soil shear strength and vibration acceleration. The environmental parameters are groundwater level and ambient humidity.

[0010] Step 3: Based on the dimensionless data of soil pressure, soil shear strength, groundwater level and ambient humidity, generate a comprehensive environmental index; based on the dimensionless data of foundation pit deformation, generate a deformation rate; based on the dimensionless data of vibration acceleration, generate a vibration intensity.

[0011] Step 4: Generate the foundation pit stability coefficient based on the comprehensive environmental index, deformation rate, and vibration intensity, and compare it with the preset safety threshold. When an unsafe state is detected, trigger the feedback mechanism to adjust the parameters of the support structure in real time.

[0012] Furthermore, the self-stabilizing foundation pit support structure technology specifically refers to an emerging support technology that uses inclined forward-bracing piles and rear tie rods to replace horizontal internal supports, combined with retaining piles, reinforcement bodies, ring beams, and reinforced cushion layers. The self-stabilizing foundation pit support technology utilizes the resistance provided by the inclined forward bracing to form a self-stabilizing structure connected with the retaining piles, controlling the horizontal displacement of the retaining piles. When the retaining structure tends to rotate, the self-stabilizing structure generates rotational resistance through the compression of the forward bracing and the pull-out resistance of the retaining piles. At the same time, the inclined forward bracing can resist the horizontal deformation of the retaining structure while also counter-pressing the soil at the bottom of the pit.

[0013] Furthermore, the specific logic for collecting soil pressure data is as follows: using a ground pressure sensor, the soil pressure at the bottom of the foundation pit is recorded in real time, and the soil pressure value is denoted as P. t ;

[0014] The specific logic for collecting the foundation pit deformation data is as follows: displacement gauges are set at feature points around the foundation pit to monitor the foundation pit deformation data in real time, which is denoted as Δh.

[0015] The specific logic behind collecting the soil shear strength data is as follows: a certain volume of undisturbed soil sample is collected from the foundation pit site, prepared into a standard specimen, placed in a uniaxial compression testing machine, and axial load is gradually applied. Stress and strain are measured, and a stress-strain curve is plotted. The elastic modulus E of the soil is obtained from the linear portion of the stress-strain curve, i.e., the initial slope. p ;

[0016] A certain volume of undisturbed soil sample was collected from the site and prepared into a standard specimen. The specimen was then placed in a uniaxial compression testing machine. During the compression process, the axial and lateral deformations were measured, and the Poisson's ratio of the soil was calculated using the following formula:

[0017]

[0018] Where v is the Poisson's ratio of the soil, ε l It is transverse strain, ε a It is axial strain;

[0019] Axial strain ε a It is the ratio of the deformation along the load direction to the original length, and the calculation formula is:

[0020]

[0021] Where, ε a ΔL is the axial strain, ΔL is the axial deformation (length after deformation minus the original length), and L0 is the original length. The transverse strain is the ratio of the deformation perpendicular to the load direction to the original length, calculated using the following formula:

[0022]

[0023] Where, ε l This refers to the lateral strain, where ΔD is the lateral deformation, i.e., the deformed length minus the original length; D0 is the original length. The shear modulus G of the soil is calculated using the following formula:

[0024]

[0025] Where G is the shear strength of the soil, and E p ρ is the elastic modulus of the soil, and v is the Poisson's ratio of the soil.

[0026] The specific logic for collecting the vibration acceleration data is as follows: An accelerometer is fixed to the self-stabilizing foundation pit support structure, and the acceleration in the x-axis, y-axis, and z-axis directions is measured respectively, denoted as A. x A y A z ;

[0027] The specific logic for collecting groundwater level data is as follows: monitoring wells are set up around the foundation pit, well pipes are installed to enter the groundwater layer, and a water level gauge is placed vertically into the well and slowly lowered until it touches the water surface. The measurement depth, i.e., the vertical distance from the wellhead to the water surface, is recorded as H. total Record the absolute height of the wellhead, i.e., the absolute height of the bottom of the pit, denoted as H. lg ;

[0028] Calculate the groundwater level using the following formula:

[0029] H w =H lg -H total

[0030] Among them, H w H represents the groundwater level. lg H represents the absolute height of the wellhead. total The depth measured from the wellhead to the water surface;

[0031] Humidity data around the foundation pit is collected in real time using a hygrometer and denoted as S. The collected humidity is compared with a preset humidity assessment threshold. If it exceeds the threshold range, the difference between the current humidity and the preset threshold is calculated and denoted as ΔS. If it does not exceed the threshold range, it is not included in the calculation of the comprehensive environmental index in the subsequent calculation.

[0032] Furthermore, the formula used to generate the comprehensive environmental index is as follows:

[0033]

[0034] Where Str is the comprehensive environmental index, G is the soil shear strength, and P is the soil shear strength. t H represents the earth pressure value. w ΔS represents the groundwater level, ΔS represents the difference between humidity and a preset threshold, and C1 represents the first constant correction index.

[0035] The deformation rate refers to the vertical deformation rate of the foundation pit and its surrounding soil within a specific time interval. The formula used to generate the deformation rate is as follows:

[0036]

[0037] Where Def is the deformation rate, Δh(t) is the deformation amount at the current moment, Δh(t-1) is the deformation amount at the previous moment, and Δt is the time interval;

[0038] The formula for generating the vibration intensity is as follows:

[0039]

[0040] Where Vib is the vibration intensity, and A x A y A z These are the components of acceleration along the x-axis, y-axis, and z-axis, respectively.

[0041] Furthermore, the formula for generating the foundation pit stability coefficient is as follows:

[0042]

[0043] Among them, FS is the foundation pit stability coefficient, Str is the comprehensive environment index, α is its preset proportional coefficient, Def is the deformation rate, β is its preset proportional coefficient, Vib is the vibration intensity, γ is its preset proportional coefficient, and α > β > γ > 0, C2 is the second constant correction index.

[0044] Further, the process of generating the foundation pit stability coefficient based on the stress index, deformation rate, and vibration intensity and comparing it with the preset safety threshold is specifically as follows:

[0045] When FS ≥ FY, it indicates that the foundation pit stability coefficient is within the preset safety threshold range, that is, the foundation pit is in a safe state, and the monitoring of the foundation pit continues to be maintained;

[0046] When FS < FY, it indicates that the foundation pit stability coefficient is less than the preset safety threshold, that is, the foundation pit is in an unsafe state. Immediately organize engineers to conduct an on-site assessment of the foundation pit, confirm the reasons for the unsafe state, and take corresponding measures;

[0047] Among them, FS is the foundation pit stability coefficient, and FY is the preset safety threshold.

[0048] Compared with the prior art, the beneficial effects of the present invention are:

[0049] The present invention optimizes the stability of the foundation pit support structure and reduces the construction period and cost by using inclined forward bracing piles to replace the traditional reinforced concrete horizontal support and utilizing the inclined forward bracing piles to provide resistance. At the same time, by collecting mechanical parameters and environmental parameters and performing dimensionless processing on them, key indicators such as stress index, deformation rate, and vibration intensity are comprehensively generated. The present invention proposes a calculation method for the foundation pit stability coefficient based on multiple parameters, which can monitor the stable state of the foundation pit in real time and trigger a feedback mechanism when an unsafe state is detected for dynamic adjustment. This multi-parameter comprehensive monitoring and adjustment method improves the safety and reliability of the foundation pit support, especially showing significant advantages under complex geological conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the overall method flow of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments.

[0052] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0053] Example:

[0054] Please see Figure 1 The present invention provides a technical solution:

[0055] An optimization design method for a self-stabilizing support system for foundation pits, comprising the following steps:

[0056] Step 1: Adopt self-stabilizing foundation pit support structure technology, use inclined forward support piles instead of reinforced concrete horizontal supports, and use the inclined forward support piles to provide resistance and achieve balance with the pressure of the soil outside the pit;

[0057] In this embodiment, the self-stabilizing foundation pit support structure technology is specifically an emerging support technology that uses inclined front bracing piles and rear tie rods to replace horizontal internal supports, combined with retaining piles, reinforcement bodies, ring beams, and reinforced cushion layers. The self-stabilizing foundation pit support technology utilizes the resistance provided by the inclined front bracing to form a self-stabilizing structure connected with the retaining piles, controlling the horizontal displacement of the retaining piles. When the retaining structure tends to rotate, the self-stabilizing structure generates rotational resistance through the compression of the front bracing and the pull-out resistance of the retaining piles. At the same time, the inclined front bracing can resist the horizontal deformation of the retaining structure while also counter-pressing the soil at the bottom of the pit.

[0058] The technical principles of self-stabilizing foundation pit support structures mainly include the inclined bracing effect, the rigid frame effect, and the heave reduction effect. The inclined bracing effect refers to the forward-bracing piles providing bearing capacity through their interaction with the soil at the bottom of the pit, and controlling the tendency of the retaining piles to deform inwards through the connection with the capping beam, thus providing resistance to soil pressure from outside the pit. The rigid frame effect refers to the use of pile rows, inclined piles, and capping beams to form a statically indeterminate rigid frame structure, improving the stability and overturning resistance of the foundation pit. The heave reduction effect refers to the counter-pressure on the soil at the bottom of the pit when the forward-bracing piles act together with the soil inside the pit, reducing the heave deformation of the soil at the bottom of the pit caused by excavation, while maintaining the stress state of the soil at the bottom of the pit and increasing the earth pressure in the passive zone.

[0059] The advantages of self-stabilizing foundation pit support technology are mainly reflected in two aspects: (1) High efficiency: This technology breaks through by using the soil inside the pit as the support point, combining earthwork trenching and reinforced cushion layer, which greatly saves the construction and maintenance time of traditional support structures; at the same time, the excavation stage realizes the large-space rapid construction of foundation pit engineering without horizontal internal support, which solves the technical shortcomings of the current foundation pit engineering with a large number of reinforced concrete supports, long construction and maintenance cycle, and low foundation pit excavation efficiency, significantly improving construction efficiency and saving construction period. (2) Low resource consumption: This technology uses a small number of inclined piles to replace dense reinforced concrete supports, which greatly reduces the consumption of temporary reinforced concrete structural materials in existing similar technologies, saves energy and reduces emissions, significantly reduces engineering construction costs, and solves the environmental problems such as construction waste, noise pollution, and dust hazards to health when dismantling reinforced concrete supports in existing similar technologies.

[0060] Step 2: Collect the mechanical and environmental parameters of the foundation pit. The mechanical parameters are soil pressure, foundation pit deformation, soil shear strength and vibration acceleration. The environmental parameters are groundwater level and ambient humidity.

[0061] In this embodiment, the specific logic for collecting soil pressure data is as follows: using a ground pressure sensor to record the soil pressure at the bottom of the foundation pit in real time, and recording the soil pressure value as P. t ;

[0062] The specific logic for collecting the foundation pit deformation data is as follows: displacement gauges are set at feature points around the foundation pit to monitor the foundation pit deformation data in real time, denoted as Δh, where the deformation data is relative to the original foundation pit.

[0063] The specific logic behind collecting the soil shear strength data is as follows: a certain volume of undisturbed soil sample is collected from the foundation pit site, prepared into a standard specimen, placed in a uniaxial compression testing machine, and axial load is gradually applied. Stress and strain are measured, and a stress-strain curve is plotted. The elastic modulus E of the soil is obtained from the linear portion of the stress-strain curve, i.e., the initial slope. p ;

[0064] A certain volume of undisturbed soil sample was collected from the site and prepared into a standard specimen. The specimen was then placed in a uniaxial compression testing machine. During the compression process, the axial and lateral deformations were measured, and the Poisson's ratio of the soil was calculated using the following formula:

[0065]

[0066] Where v is the Poisson's ratio of the soil, ε l It is transverse strain, ε a It is axial strain;

[0067] Axial strain ε aIt is the ratio of the deformation along the load direction to the original length, and the calculation formula is:

[0068]

[0069] Where, ε a ΔL is the axial strain, ΔL is the axial deformation (length after deformation minus the original length), and L0 is the original length. The transverse strain is the ratio of the deformation perpendicular to the load direction to the original length, calculated using the following formula:

[0070]

[0071] Where, ε l This refers to the lateral strain, where ΔD is the lateral deformation, i.e., the deformed length minus the original length; D0 is the original length. The shear modulus G of the soil is calculated using the following formula:

[0072]

[0073] Where G is the shear strength of the soil, and E p ρ is the elastic modulus of the soil, and v is the Poisson's ratio of the soil.

[0074] The specific logic for collecting the vibration acceleration data is as follows: An accelerometer is fixed to the self-stabilizing foundation pit support structure, and the acceleration in the x-axis, y-axis, and z-axis directions is measured respectively, denoted as A. x A y A z ;

[0075] The specific logic for collecting groundwater level data is as follows: monitoring wells are set up around the foundation pit, well pipes are installed to enter the groundwater layer, and a water level gauge is placed vertically into the well and slowly lowered until it touches the water surface. The measurement depth, i.e., the vertical distance from the wellhead to the water surface, is recorded as H. total Record the absolute height of the wellhead, i.e., the absolute height of the bottom of the pit, denoted as H. lg ;

[0076] Calculate the groundwater level using the following formula:

[0077] H w =H lg -H total

[0078] Among them, H w H represents the groundwater level. lg H represents the absolute height of the wellhead. total The depth measured from the wellhead to the water surface;

[0079] Humidity data around the foundation pit is collected in real time using a hygrometer and denoted as S. The collected humidity is compared with a preset humidity assessment threshold. If it exceeds the threshold range, the difference between the current humidity and the preset threshold is calculated and denoted as ΔS. If it does not exceed the threshold range, it is not included in the calculation of the comprehensive environmental index in the subsequent calculation.

[0080] Step 2 systematically collects the mechanical and environmental parameters of the foundation pit, providing a comprehensive and detailed data foundation for subsequent analysis. This method not only covers the physical and mechanical properties of the soil but also considers the impact of environmental factors on the stability of the foundation pit, making the assessment more accurate and reliable, thereby ensuring a high degree of correlation between the support design and the actual situation. Compared with existing technologies, the advantage of Step 2 lies in its multi-dimensional data acquisition method, which can more comprehensively reflect the actual working conditions of the foundation pit. Traditional methods often focus on a single parameter or lack sufficient environmental considerations, resulting in incomplete assessment results. By combining mechanical and environmental parameters, potential risks and instability factors can be identified more accurately, thereby improving the accuracy and effectiveness of foundation pit monitoring.

[0081] In this patented solution, step 2 provides the necessary data support for the subsequent generation of comprehensive environmental indices, deformation rates, and vibration intensity. This data-driven process ensures the scientific rigor and accuracy of real-time monitoring and evaluation, making the overall solution more flexible and effective in responding to changes in the foundation pit, thereby improving the safety and construction efficiency of the foundation pit. The effective use of this information can trigger a timely feedback mechanism, allowing for necessary adjustments and further ensuring the stability of the foundation pit.

[0082] Step 3: Based on the dimensionless data of soil pressure, soil shear strength, groundwater level and ambient humidity, generate a comprehensive environmental index; based on the dimensionless data of foundation pit deformation, generate a deformation rate; based on the dimensionless data of vibration acceleration, generate a vibration intensity.

[0083] In this embodiment, the formula for generating the comprehensive environmental index is as follows:

[0084]

[0085] Where Str is the comprehensive environmental index, G is the soil shear strength, and P is the soil shear strength. t H represents the earth pressure value. w Let P be the groundwater level, ΔS be the difference between humidity and a preset threshold, and C1 be the first constant correction exponent; when the soil pressure P... tIncreasing G may lead to deformation or slippage of the foundation pit wall, thus decreasing the comprehensive environmental index Str. Soil shear strength is the soil's ability to resist shear failure; higher shear strength results in better foundation pit stability and better resistance to slippage caused by soil pressure or external loads. Therefore, as G increases, the comprehensive environmental index Str increases. A rise in groundwater level increases buoyancy, which may significantly reduce the effective stress of the soil, thereby reducing its shear strength and affecting the stability of the foundation pit. Therefore, when H... w As ΔS increases, the comprehensive environmental index Str decreases; changes in humidity affect the physical and chemical properties of soil, such as its expansibility and compressibility, as well as its strength and permeability. Therefore, as ΔS increases, the comprehensive environmental index Str decreases; this indicates that G and Str are positively correlated. t H w ΔS and Str are negatively correlated.

[0086] The deformation rate refers to the vertical deformation rate of the foundation pit and its surrounding soil within a specific time interval. The formula used to generate the deformation rate is as follows:

[0087]

[0088] Where Def is the deformation rate, Δh(t) is the deformation amount at the current moment, Δh(t-1) is the deformation amount at the previous moment, and Δt is the time interval;

[0089] The formula for generating the vibration intensity is as follows:

[0090]

[0091] Where Vib is the vibration intensity, and A x A y A z These are the components of acceleration along the x-axis, y-axis, and z-axis, respectively.

[0092] Step 3 generates a comprehensive environmental index, deformation rate, and vibration intensity through dimensionless processing, making the comparison and analysis of different parameters more intuitive and scientific. This processing method eliminates the influence of dimensions, allowing various complex soil and environmental factors to be evaluated under the same standard, thereby improving data comparability and analytical accuracy. Compared with existing technologies, the advantage of Step 3 lies in its standardized data processing method, which effectively integrates multiple influencing factors and presents the overall stability state of the foundation pit. This systematic approach avoids errors caused by parameter differences in traditional assessments, providing a more comprehensive safety assessment and a stronger basis for decision-making.

[0093] In the patent solution, the implementation of step 3 lays the foundation for the generation of the foundation pit stability coefficient, ensuring the scientificity and effectiveness of subsequent safety assessments and risk analyses. By integrating multiple parameters to generate a comprehensive index, this step can provide specific evaluation criteria for the real-time monitoring system, enabling the overall solution to quickly respond when facing an unsafe state, perform effective parameter adjustments and structural optimizations, thereby further enhancing the safety and construction efficiency of the foundation pit.

[0094] Step 4: Generate the foundation pit stability coefficient based on the comprehensive environment index, deformation rate, and vibration intensity, and compare it with a preset safety threshold. When an unsafe state is detected, trigger a feedback mechanism to adjust the parameters of the support structure in real time.

[0095] In this embodiment, the formula for generating the foundation pit stability coefficient is as follows:

[0096]

[0097] Among them, FS is the foundation pit stability coefficient, Str is the comprehensive environment index, α is its preset proportional coefficient, Def is the deformation rate, β is its preset proportional coefficient, Vib is the vibration intensity, γ is its preset proportional coefficient, and α > β > γ > 0. This is because understanding the bearing capacity of the soil mass and the impact of environmental changes on the foundation pit is an important basis for evaluating stability. In the case of being close to a traffic artery or a large construction project, the impact of vibration intensity may be significant, and its weight will increase at this time. However, for a foundation pit farther away from the vibration source, the impact of vibration may be relatively small. C2 is the second constant correction index; when the comprehensive environment index increases, it indicates that the comprehensive environmental conditions around the foundation pit are getting better, and the foundation pit stability coefficient FS increases; when the deformation rate Def or the vibration intensity Vib increases, the foundation pit stability coefficient FS decreases; that is to say, Str and FS are in a positive correlation relationship, and Def, Vib and FS are in a negative correlation relationship.

[0098] The process of generating the foundation pit stability coefficient based on the stress index, deformation rate, and vibration intensity and comparing it with the preset safety threshold is specifically as follows:

[0099] When FS ≥ FY, it indicates that the foundation pit stability coefficient is within the preset safety threshold range, that is, the foundation pit is in a safe state, and continue to monitor the foundation pit;

[0100] When FS < FY, it indicates that the foundation pit stability coefficient is less than the preset safety threshold, that is, the foundation pit is in an unsafe state. Immediately organize engineers to conduct an on-site assessment of the foundation pit, confirm the reasons for the unsafe state, and take corresponding measures;

[0101] Among them, FS is the foundation pit stability coefficient, and FY is the preset safety threshold.

[0102] Compared to existing technologies, step 4 has the advantage of enabling real-time monitoring and feedback mechanisms. This allows monitoring data to go beyond passive recording, actively driving adjustments to design and construction strategies. Traditional methods often lack dynamic response, resulting in delayed adjustments when deformation or other problems occur, increasing construction risks. The real-time adjustment mechanism significantly reduces the probability of accidents, improving construction safety and efficiency.

[0103] In this patented solution, step 4 provides flexibility and adaptability to the overall solution, allowing for timely adjustments based on actual conditions during construction. This mechanism not only optimizes resource allocation and reduces unnecessary material and manpower inputs, but also effectively addresses unforeseen circumstances, ensuring the smooth progress of foundation pit construction and further enhancing the overall safety and economy of the project.

[0104] The specific values ​​of α, β, and γ in the formula are generally determined by those skilled in the art based on the actual situation. Multiple sets of sample data are collected by those skilled in the art, and a corresponding preset proportion coefficient is set for each set of sample data. The preset proportion coefficient and the collected sample data are substituted into the formula. Through repeated experiments and parameter adjustments, the accuracy of the model output and the rationality of the results are observed. These factor coefficients are gradually adjusted, and the performance and effect of the model under different parameter settings are compared to find the optimal coefficient combination. The calculated factor coefficients are screened and the average value is taken to obtain the values ​​of α, β, and γ.

[0105] In addition, the size of the preset factor coefficient is a specific value obtained by quantifying each parameter. In order to facilitate subsequent comparison, the size of the coefficient depends on the amount of sample data and the preset ratio coefficient initially set by those skilled in the art for each set of sample data. It is not unique, as long as it does not affect the ratio relationship between the parameter and the quantified value.

[0106] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0107] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0108] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0109] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A method for optimizing design of a self-stable type supporting system for a foundation pit, characterized in that, The specific steps include: Step 1: using self-stabilizing foundation pit support structure technology, using inclined front support pile instead of reinforced concrete horizontal support, using inclined front support pile to provide resistance, and balancing with the pressure of the soil outside the pit; Step 2: collecting mechanical parameters and environmental parameters of the foundation pit, the mechanical parameters being soil pressure, foundation pit deformation, soil shear strength and vibration acceleration, and the environmental parameters being underground water level and environmental humidity; Step 3: generating a comprehensive environmental index based on the dimensionless soil pressure, soil shear strength, underground water level and environmental humidity data, generating a deformation rate based on the dimensionless foundation pit deformation data, and generating a vibration intensity based on the dimensionless vibration acceleration data; Step 4: generating a foundation pit stability coefficient according to the comprehensive environmental index, the deformation rate and the vibration intensity, and comparing it with a preset safety threshold, triggering a feedback mechanism to adjust the parameters of the support structure in real time when an unsafe state is detected; The formula for generating the comprehensive environmental index is: ； wherein, is a comprehensive environmental index, is a soil shear strength, is a soil pressure value, is a groundwater level, is a difference between the humidity and a preset threshold value, is a first constant correction index; The deformation rate refers to the vertical deformation rate of the foundation pit and its surrounding soil within a certain time interval, and the formula for generating the deformation rate is: ； wherein, is a deformation rate, is a deformation amount at the current time, is a deformation amount at the previous time, is a time interval; The formula for generating the vibration intensity is: ； wherein is the vibration intensity, , , are the components of the acceleration on the x-axis, y-axis and z-axis, respectively; The formula for generating the foundation pit stability coefficient is as follows: ； wherein, is a foundation pit stability coefficient, is a comprehensive environmental index, is a preset proportion coefficient thereof, is a deformation rate, is a preset proportion coefficient thereof, is a vibration intensity, is a preset proportion coefficient thereof, and , is a second constant correction index.

2. The method according to claim 1, wherein: The self-stabilizing foundation pit support structure technology specifically refers to a support technology that uses inclined front support piles, rear pull rods to replace horizontal internal supports, and is combined with enclosure piles, reinforcing bodies, ring beams and reinforced cushion layers to form a self-stabilizing foundation pit support structure. The self-stabilizing foundation pit support structure technology uses the resistance provided by the inclined front support to form a self-stabilizing structure with the enclosure pile, controlling the horizontal displacement of the enclosure pile. When the enclosure tends to rotate, the self-stabilizing structure is compressed by the front support, and the enclosure pile and the inclined front support jointly generate rotational resistance, while the inclined front support also resists the horizontal deformation of the enclosure and presses the soil at the bottom of the pit.

3. The method according to claim 1, wherein the method is characterized by: The specific logic for collecting the soil pressure data is: using a formation pressure sensor to record the soil pressure at the bottom of the foundation pit in real time, and recording the soil pressure value as ; The specific logic for collecting the foundation pit deformation data is: setting displacement meters at positions of feature points around the foundation pit, monitoring the foundation pit deformation data in real time, denoted as ; The specific logic for collecting the soil body shear strength data is as follows: collecting a certain volume of undisturbed soil sample from the foundation site, preparing into a standard test piece, putting the test piece into a uniaxial compression testing machine, gradually applying axial load, measuring stress and strain, and drawing a stress-strain curve, obtaining the elastic modulus of the soil body from the linear part of the stress-strain curve, i.e. the initial slope ; A certain volume of undisturbed soil sample is collected from the field and prepared into a standard test specimen. The test specimen is placed in a uniaxial compression testing machine. During the compression process, the axial deformation and lateral deformation are measured, and the Poisson's ratio of the soil is calculated according to the following formula: ； wherein, is the Poisson's ratio of the soil mass, is the lateral strain, is the axial strain; axial strain is the ratio of the deformation in the load direction to the original length, and is calculated as ； wherein, is the axial strain, is the axial deformation, i.e. the length after deformation minus the original length; is the original length; The lateral strain is the ratio of the deformation perpendicular to the load direction to the original length, and the calculation formula is: ； wherein, is the transverse strain, is the transverse deformation, i.e. the length after deformation minus the original length; is the original length; The shear modulus of the soil is calculated using the following formula : ； wherein, is the soil shear strength, is the soil elastic modulus, is the soil Poisson's ratio; The specific logic for collecting vibration acceleration data is: fixing the accelerometer on the self-stabilizing foundation pit support structure, measuring the acceleration in the x-axis, y-axis and z-axis directions respectively, denoted as , , ; The specific logic for collecting the groundwater level data is as follows: monitoring wells are arranged around the foundation pit, well pipes are installed into the groundwater layer, a water level gauge is vertically placed into the well and slowly lowered until it touches the water surface, the measured depth, i.e. the vertical distance from the well mouth to the water surface, is recorded, denoted as The absolute height of the well mouth, i.e. the absolute height of the bottom of the foundation pit, is recorded, denoted as ​ The following formula is used to calculate the underground water level: ； wherein, is the groundwater level, is the absolute height of the wellhead, is the depth of the wellhead to the water surface measurement; The humidity data around the foundation pit are collected in real time using a humidity meter, denoted as The collected humidity is compared with a preset humidity evaluation threshold, and if it exceeds the threshold range, the difference between the current humidity and the preset threshold is calculated, denoted as If the threshold range is not exceeded, it is not included in the calculation when calculating the comprehensive environment index subsequently.

4. The method according to claim 1, wherein the method is characterized by: The process of generating the foundation pit stability coefficient according to the comprehensive environmental index, the deformation rate and the vibration intensity, and comparing it with the preset safety threshold, specifically includes: When the foundation pit stability coefficient is within the preset safety threshold range, i.e. the foundation pit is in a safe state, the monitoring of the foundation pit is continued. When , it indicates that the stability coefficient of the foundation pit is less than the preset safety threshold, i.e. the foundation pit is in an unsafe state, and engineers are immediately organized to conduct on-site evaluation on the foundation pit, confirm the cause of the unsafe state, and take corresponding measures. wherein, is a foundation pit stability coefficient, is a preset safety threshold.

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