Differentiated Pile Length Foundation Reinforcement System and Method for Precast Concrete Piles in Frozen Soil Regions

Abstract

This invention discloses a differential pile length foundation reinforcement system and method for precast concrete piles in permafrost regions, relating to the field of permafrost engineering technology. The system includes the following steps: S1, constructing a freezing sensitivity factor index; S2, constructing a multi-level pile length design function; S3, constructing a control model for differences in adjacent pile lengths; S4, designing pile end structures with differentiated base diameters; S5, evaluating the coupling relationship between the thermal-mechanical coupling response of the pile end; S6, real-time monitoring of pile stress changes; and building the system based on the above methods. This invention achieves precise matching between pile length and frost heave risk, and through the construction of models such as multi-level pile length design functions, dynamically couples the pile design with the regional permafrost environment, effectively avoiding structural stress concentration problems caused by sudden changes in pile length. The thermal-mechanical coupling response evaluation and real-time monitoring of pile stress enable full-process control of the pile's working state, significantly improving the deformation resistance and operational reliability of pile foundation systems in permafrost regions.

Description

Technical Field

[0001] This invention relates to the field of frozen soil engineering technology, specifically to a foundation reinforcement system and method for precast concrete piles with differentiated pile lengths in frozen soil regions. Background Technology

[0002] When constructing foundation engineering projects in permafrost regions, the foundation is significantly affected by seasonal freeze-thaw cycles, making it highly susceptible to engineering defects such as uneven settlement, pile uplift, and structural cracking. To enhance foundation stability, precast concrete piles are widely used. However, traditional pile foundation designs often employ fixed pile lengths and uniform pile types, neglecting the differences in freezing sensitivity of the foundation soil layers at different regions and depths. Especially in permafrost environments, the temperature gradient, moisture content, and soil distribution are highly heterogeneous, resulting in significant differences in frost heave characteristics between different locations and even at different depths within the same region.

[0003] Existing design methods often employ simple safety margin expansion to address frost heave risks, failing to establish a coupling model between pile length and ground freezing sensitivity. They also lack transition control mechanisms for abrupt structural mechanical response changes caused by sudden changes in pile length, making it difficult to achieve differentiated and precise control of the pile's frost heave resistance. Furthermore, existing designs neglect the buffering effect of pile tip geometry on the thermo-mechanical response in frozen zones. The pile monitoring and control mechanisms are inadequate, lacking intelligent adjustment capabilities supported by feedback mechanisms, resulting in significant failure risks in pile foundation engineering under complex frozen soil conditions. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a foundation reinforcement system and method for precast concrete piles with differentiated pile lengths in permafrost regions, thereby resolving the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, embodiments of the present invention provide a method for reinforcing foundations with differentiated pile lengths of precast concrete piles in permafrost regions, comprising the following steps:

[0007] S1. Construct a freezing sensitivity factor index to conduct a zonal assessment of the foundation layers with frost heave risk in various engineering areas within the permafrost region.

[0008] S2. Based on the distribution results of the freezing sensitivity factor, a multi-level pile length design function is constructed to determine the classification of the three-level pile types of "short pile - medium pile - long pile" in each engineering area;

[0009] S3. Based on the classification results of the three-level pile type, construct a control model for the difference in adjacent pile lengths and optimize the transition law between pile lengths in different regions;

[0010] S4. Based on the pile length difference control results and combined with the freezing sensitivity of the engineering area where each pile is located, design a pile end structure with a differentiated enlarged base diameter.

[0011] S5. After determining the enlargement radius of the pile end structure, evaluate the coupling relationship between the thermal expansion stress of the pile end and the response of the pile body structure during the freezing process.

[0012] S6. Real-time monitoring of pile stress changes, and reverse adjustment of the pile end buffer structure or additional constraint device to achieve effective control of foundation reinforcement for different pile lengths.

[0013] To further optimize this technical solution, in step S1, in the permafrost region, a freezing sensitivity factor is established based on factors such as temperature gradient, formation moisture content, and fine particle ratio. The freezing sensitivity factor model is used to assess the frost heave risk of the k-th stratum.

[0014]

[0015] in:

[0016] : The average geothermal gradient of the k-th soil layer;

[0017] : Moisture content of the k-th soil layer;

[0018] : The mass fraction of fine particles in the k-th soil layer;

[0019] : Empirical weighting coefficient, satisfying ;

[0020] This model is used for frozen sensitive layer identification, based on... The size of the foundation is used to divide the foundation into three sensitive zones: high, medium, and low, and these zones are marked on the foundation layering diagram as a basis for pile length design.

[0021] To further optimize this technical solution, in step S2, the constructed multi-level pile length design function is used to calculate the target pile length in the m-th engineering area;

[0022] The function is shown below:

[0023]

[0024] in:

[0025] : Design pile length for the m-th engineering area;

[0026] Safety factor, used to amplify the control depth of the sensitive layer;

[0027] : The freeze sensitivity factor obtained in step S1;

[0028] The thickness of the k-th soil layer;

[0029] The set of frost heave risk layers contained in the m-th engineering area;

[0030] This model transforms the frost heave of the foundation into specific pile length design indicators, realizing the mapping from geological characteristics to structural dimensions and completing the reasonable division of the three pile types: short pile, medium pile, and long pile.

[0031] To further optimize this technical solution, in step S3, the adjacent pile length difference control model optimizes the transition law between different pile lengths from the perspective of pile group arrangement, in order to reduce stress concentration and differential deformation due to frost heave between piles caused by sudden changes in pile length.

[0032] The control model for the difference in adjacent pile lengths is shown below:

[0033]

[0034] in:

[0035] : The difference in pile length between adjacent piles i and j;

[0036] : The calculation results of the lengths of the i-th and j-th adjacent piles obtained through step S2;

[0037] : The average length of piles within the current pile group area;

[0038] Transition control coefficient, typically not exceeding 0.25;

[0039] By limiting the difference in length between adjacent piles, the frost heave deformation coordination of the pile group structure is maintained, and the synergistic effect between piles and soil is enhanced.

[0040] To further optimize this technical solution, in step S4, when designing a pile end structure with a differentiated enlarged bottom diameter, the pile end is kept under balanced stress by adjusting the enlarged bottom diameter, so as to avoid local pile end pull-up or sinking caused by frost heave differences, thereby improving the pile end's frost heave resistance.

[0041] A model for the enlarged base radius of the pile tip is constructed to realize the design of pile tip structures with differentiated enlarged base diameters.

[0042] The pile tip enlargement radius model is further optimized as follows:

[0043]

[0044] in:

[0045] : The radius of the enlarged base of the i-th pile;

[0046] Standard pile tip radius;

[0047] : The maximum freezing sensitivity factor in the soil layer traversed by the i-th pile;

[0048] : The average freezing sensitivity within the i-th engineering region;

[0049] In areas sensitive to frost heave, the pile tip enlargement is automatically increased to improve frost pull-out resistance and enhance the stability of pile tip bearing capacity.

[0050] To further optimize this technical solution, in step S5, when evaluating the coupling relationship, a thermo-mechanical synergistic control response model is constructed to identify the critical load of frost heave that key pile locations may bear, and outputs a thermo-mechanical response factor for adjusting the allowable displacement limit of the structure, providing support for actual construction monitoring.

[0051] To further optimize this technical solution, the thermo-mechanical coordinated regulation response model is as follows:

[0052]

[0053] in:

[0054] : Thermo-mechanical response factor of the i-th pile;

[0055] : The freezing depth of the area where the i-th pile is located;

[0056] : Adjustment coefficient, reflecting the effect of freezing on load release;

[0057] when When the load exceeds the design threshold, a load release structure is used for compensation and release to ensure the integrity of the pile body and provide a quantitative judgment standard.

[0058] To further optimize this technical solution, in step S6, a pile end hysteresis deformation adjustment model is constructed to monitor stress changes in real time. The model is shown below:

[0059]

[0060] in:

[0061] : The pile tip deformation hysteresis adjustment factor of the i-th pile;

[0062] : The instantaneous deformation of the i-th pile at time t;

[0063] : The maximum allowable deformation of the i-th pile;

[0064] when When the temperature drops to the lower warning limit, the buffer structure at the pile tip is activated to absorb excessive deformation and prevent the pile body from cracking or becoming unstable.

[0065] A foundation reinforcement system for precast concrete piles with differentiated pile lengths in permafrost regions is constructed based on the aforementioned reinforcement method. The functional modules of this system include:

[0066] Partition evaluation module;

[0067] Pile length classification design module;

[0068] Pile length difference control module;

[0069] Pile end structure design module;

[0070] Coupled response evaluation module;

[0071] Pile stress monitoring module.

[0072] In a second aspect, embodiments of the present invention provide a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, they implement the steps of a differential pile length foundation reinforcement system and method for precast concrete piles in frozen soil areas as described in the first aspect of the present invention.

[0073] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, they implement the steps of a differential pile length foundation reinforcement system and method for precast concrete piles in frozen soil areas as described in the first aspect of the present invention.

[0074] Compared with the prior art, the present invention provides a foundation reinforcement system and method for precast concrete piles with differentiated pile lengths in frozen soil areas, which has the following beneficial effects:

[0075] This differentiated pile length foundation reinforcement system and method for precast concrete piles in permafrost regions achieves precise matching between pile length and frost heave risk by constructing and identifying freezing sensitivity factors. Furthermore, by building multi-level pile length design functions and adjacent pile length difference control models, the pile design is dynamically coupled with the regional permafrost environment, effectively avoiding structural stress concentration problems caused by abrupt changes in pile length. Simultaneously, by combining thermo-mechanical coupling response evaluation and real-time pile stress monitoring mechanisms, the entire process of pile operation is controlled, significantly improving the deformation resistance and operational reliability of pile foundation systems in permafrost regions. Attached Figure Description

[0076] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0077] Figure 1 This is a schematic flowchart of a method for reinforcing the foundation of precast concrete piles in frozen soil areas, as proposed in this invention.

[0078] Figure 2 This is a schematic diagram of the functional modules of a foundation reinforcement system for precast concrete piles with differentiated pile lengths in frozen soil regions, as proposed in this invention. Detailed Implementation

[0079] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0080] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0081] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0082] Example 1:

[0083] Reference Figure 1 This is the first embodiment of the present invention, which provides a method for reinforcing the foundation of precast concrete piles with differentiated pile lengths in frozen soil areas, including the following steps:

[0084] S1. Construct a freezing sensitivity factor index to conduct a zonal assessment of the foundation layers in each engineering area within the permafrost region that are at risk of frost heave.

[0085] Unlike existing methods for designing frozen soil foundations that often rely on empirical stratigraphic determination or solely on geothermal depth data to delineate sensitive zones, this step introduces a freezing sensitivity factor as a quantitative indicator. By weighting and combining three types of frost heave driving parameters—geothermal gradient, moisture content, and fine particle mass fraction—it achieves a zonal assessment of foundation frost heave risk. This method not only overcomes the subjective classification and ambiguous zoning shortcomings of traditional methods but also allows for adjustments to the sensitivity assessment structure based on actual geological conditions, making foundation zoning more targeted and adjustable. Its advantages include: more comprehensive assessment dimensions, more refined zoning results, and the ability to provide accurate stratigraphic foundation data support for subsequent differentiated pile length design, thereby improving frost heave resistance reliability from the outset.

[0086] In permafrost regions, a freezing sensitivity factor is established based on factors such as temperature gradient, formation water content, and fine particle size distribution. The freezing sensitivity factor model is used to assess the frost heave risk of the k-th stratum.

[0087]

[0088] in:

[0089] The average geothermal gradient of the k-th soil layer reflects the degree to which the soil layer is affected by external temperature; the larger the gradient, the higher the freezing potential.

[0090] The water content of the k-th soil layer represents the potential amount of ice formation and is the basic medium for frost heave.

[0091] The fine particle mass fraction of the k-th soil layer determines the capillary action and capillary water freezing behavior in the soil and is the main structural factor for the release of frost heave force.

[0092] : Empirical weighting coefficient, satisfying The parameters were set based on measured data from permafrost engineering projects in different regions, reflecting the importance of the factors in those regions.

[0093] This model is used for frozen sensitive layer identification, based on... The size of the foundation is used to divide the foundation into three sensitive zones: high, medium, and low, and these zones are marked on the foundation layering diagram as a basis for pile length design.

[0094] When using it, the stratigraphic data of each layer obtained from drilling and geological exploration are uniformly organized and then input into the model to calculate the stratigraphic values ​​of each layer. And use this as a criterion for classification (e.g., high-sensitivity areas). Medium-sensitive area Low-sensitivity areas This process ultimately resulted in a high-precision foundation zoning map, providing input for the next step of pile length differentiation and structural optimization.

[0095] S2. Based on the distribution results of the freezing sensitivity factor, construct a multi-level pile length design function to determine the classification of the three-level pile types of "short pile-medium pile-long pile" in each engineering area.

[0096] Traditional pile foundation design in permafrost regions often employs fixed pile lengths or relies on experience to set pile depths for different areas. This lacks a quantitative response to the degree of frost heave impact in specific strata, resulting in insufficient pile lengths to penetrate highly sensitive layers or unnecessary resource waste due to excessive depth. This step introduces a multi-level pile length design function, combining it with the freezing sensitivity factor obtained from precise zoning in step S1. A weighted thickness accumulation method integrates the multi-layered frost heave impact into a structural response index, achieving direct coupling between pile length and permafrost risk intensity. This approach possesses high adaptability and engineering specificity, allowing for dynamic adjustment of pile length levels. This ensures that the pile foundation design meets frost heave resistance requirements while optimizing resource allocation, improving engineering economy and durability.

[0097] A multi-level pile length design function is constructed for calculating the target pile length in the m-th engineering area;

[0098] The function is shown below:

[0099]

[0100] in:

[0101] : Design pile length for the m-th engineering area;

[0102] Safety factor, used to amplify the control depth of the sensitive layer;

[0103] : The freeze sensitivity factor obtained in step S1;

[0104] The thickness of the k-th soil layer;

[0105] The set of frost heave risk layers contained in the m-th engineering area;

[0106] This model transforms the frost heave of the foundation into specific pile length design indicators, realizing the mapping from geological characteristics to structural dimensions and completing the reasonable division of the three pile types: short pile, medium pile, and long pile.

[0107] In terms of usage, engineering designers should refer to each layer obtained in step S1. and The data can be directly substituted into the model to output differentiated pile length levels according to the region. If the pile length value output by the model falls within the set threshold range, it can be classified into standard pile type levels, such as short piles (shallow stability), medium piles (deepening type in medium risk areas), and long piles (anchoring type in highly sensitive areas), providing input parameters for the next step of pile-to-pile collaborative design.

[0108] S3. Based on the classification results of the three-level pile type, construct a control model for the difference in adjacent pile lengths and optimize the transition law between pile lengths in different regions.

[0109] In traditional pile foundation design in permafrost regions, although the relationship between the length of a single pile and the frost heave layer is considered, the mutual interference between piles of different lengths within a pile group is often overlooked. This is especially true in highly variable frost heave strata, where abrupt changes in pile length can easily lead to differential settlement at the pile tip, uplift instability, or stress concentration. Step S3 introduces an adjacent pile length difference control model. Starting from the pile group system level, it imposes constraints on the length difference between adjacent piles, achieving transitional optimization and coordinated control of the differentiated pile length arrangement. This method not only improves the collaborative bearing capacity of the pile-soil system but also effectively reduces structural hazards caused by differential frost heave deformation, providing a more systematic and progressive structural control strategy for foundation stability in high-altitude and cold regions.

[0110] The adjacent pile length difference control model optimizes the transition law between different pile lengths from the perspective of pile group layout, and is used to reduce stress concentration and differential deformation due to frost heave between piles caused by sudden changes in pile length.

[0111] The control model for the difference in adjacent pile lengths is shown below:

[0112]

[0113] in:

[0114] : The difference in pile length between adjacent piles i and j;

[0115] : The calculation results of the lengths of the i-th and j-th adjacent piles obtained through step S2;

[0116] : The average length of piles within the current pile group area;

[0117] Transition control coefficient, typically not exceeding 0.25, may be fine-tuned depending on the degree of frost heave difference;

[0118] By limiting the difference in length between adjacent piles, the frost heave deformation coordination of the pile group structure is maintained, and the synergistic effect between piles and soil is enhanced.

[0119] The usage method is as follows: After determining the length of each pile, calculate the difference in pile length between adjacent piles according to the pile group layout diagram, and substitute it into the model for judgment. Once the difference between a pair of piles exceeds the upper limit value... If the problem persists, it needs to be optimized. Common optimization methods include: equivalent reduction of long piles or reinforcement of short piles, or introduction of variable cross-section structures to alleviate stress concentration during the transition.

[0120] S4. Based on the results of pile length difference control and combined with the freezing sensitivity of the engineering area where each pile is located, design a pile end structure with a differentiated enlarged base diameter.

[0121] Traditional pile tip enlargement designs typically employ uniform specifications, failing to make targeted adjustments based on the frost heave strength and pile length differences in different regions. This can easily lead to insufficient pile tip bearing capacity or wasted resources. This approach, however, achieves zoned adaptive design of the pile tip enlargement structure by coupling the frozen soil zoning sensitivity with pile length difference control results. Based on the freezing sensitivity of the soil where the pile tip is located and the degree of length difference between adjacent piles, the enlargement radius of each pile is autonomously adjusted to ensure that the pile tip maintains a reasonable stress state under the influence of frost heave heterogeneity, thus improving overall uplift stability. This method balances bearing capacity and material optimization, avoiding local structural failures caused by frost heave differences, and represents a systematic improvement in the frost-resistant stability design of pile foundation structures in frozen soil regions.

[0122] When designing pile end structures with differentiated enlarged base diameters, adjusting the enlarged base diameter ensures that the pile end is subjected to balanced forces, preventing localized pile end pull-up or sinking due to differences in frost heave, thereby improving the pile end's resistance to frost heave.

[0123] A model for the enlarged base radius of the pile tip is constructed to realize the design of pile tip structures with differentiated enlarged base diameters.

[0124] The pile tip enlargement radius model is shown below:

[0125]

[0126] in:

[0127] : The radius of the enlarged base of the i-th pile;

[0128] The standard pile tip radius is usually determined based on the design of standard piles in permafrost-free areas.

[0129] : The maximum freezing sensitivity factor in the soil layer traversed by the i-th pile;

[0130] : The average freezing sensitivity within the i-th engineering region;

[0131] In areas sensitive to frost heave, the pile tip enlargement is automatically increased to improve frost pull-out resistance and enhance the stability of pile tip bearing capacity.

[0132] The core idea of ​​this model is that when the maximum frost heave risk of a certain pile in the area is significantly higher than the average level of the surrounding area, and the pile length difference between it and the adjacent piles is large, its base diameter should be significantly increased to enhance its pull-out resistance and stability.

[0133] In terms of operation, first substitute the parameters obtained from S1-S3 to calculate the required enlargement radius for each pile. If the calculated result is significantly larger than the standard diameter, it indicates that the pile is located in a high-risk frost heave zone or at a point of abrupt change in pile length, and an enlarged base reinforcement design should be preferred; if the result is close to... If the geological and structural transition at the pile location is uniform, then a conventional pile type can be used.

[0134] S5. After determining the enlargement radius of the pile end structure, evaluate the coupling relationship between the thermal expansion stress of the pile end and the response of the pile body structure during the freezing process.

[0135] In current designs for precast concrete piles in permafrost regions, most schemes only statically consider pile tip bearing capacity and structural strength, neglecting the thermo-mechanical coupling effect during freezing. Especially when frost heave force dynamically changes with temperature gradients, the pile tip and shaft are highly susceptible to structural impact loads, leading to microcracks or fractures. This step introduces a thermo-mechanical synergistic control response model, systematically constructing coupling indices between thermal stress, pile tip dimensions, and soil behavior, thereby guiding the structural response determination under critical frozen soil load conditions. Through the design of thermo-mechanical response factors, an active and dynamic anti-frost expansion control mechanism can be provided for precast concrete piles in high-altitude and cold regions, significantly improving the structure's durability and safety margin.

[0136] When assessing the coupling relationship, a thermo-mechanical synergistic control response model is constructed to identify the critical frost heave uplift load that key pile locations may bear, and outputs thermo-mechanical response factors to adjust the allowable displacement limit of the structure, providing support for actual construction monitoring.

[0137] The thermo-mechanical coordinated regulation response model is as follows:

[0138]

[0139] in:

[0140] : Thermo-mechanical response factor of the i-th pile;

[0141] : The freezing depth of the area where the i-th pile is located (the amount of stress released due to freezing of soil per unit depth), is derived from the calculation of actual air temperature and soil thermal conductivity;

[0142] : Adjustment coefficient, reflecting the effect of freezing on load release, can be adjusted to adapt to different types of frozen soil;

[0143] when When the load exceeds the design threshold, a load release structure is used for compensation and release to ensure the integrity of the pile body and provide a quantitative judgment standard.

[0144] In the model, the thermo-mechanical response factor This comprehensively reflects the coupling strength between pile tip dimensions, pile structure, freezing strength, and freezing depth. Its physical meaning can be interpreted as "the thermo-mechanical response strength of the pile under unit freezing force." When... An excessively large value indicates that the pile is located in a zone of concentrated freezing stress, making the structure susceptible to damage from frost heave.

[0145] The freezing depth of the region was obtained through geological and climatic data. and select appropriate value;

[0146] Calculate each pile If the response factor of a certain pile exceeds a preset threshold (such as engineering experience value or model simulation result), it is marked as a critical pile position.

[0147] For critical pile locations, load release devices should be prioritized, such as prestressed unloading structures, micro-perturbation electric heating devices, or phased thawing pipelines.

[0148] This model not only serves as a predictive tool for thermal instability, but can also guide the priority configuration of load-release structures, the arrangement of construction sequences, and the layout of monitoring points. It is an important technical support for the active safety control of pile foundation systems in permafrost regions.

[0149] S6. Real-time monitoring of pile stress changes, and reverse adjustment of the pile end buffer structure or additional constraint device to achieve effective control of foundation reinforcement for different pile lengths.

[0150] Existing pile foundation technologies in permafrost regions mostly focus on the concept of "rigid frost resistance," emphasizing increasing pile strength or thickening the pile tip to rigidly resist frost heave pressure. However, the freezing-thawing cycle of permafrost exhibits significant dynamic changes, particularly with a noticeable lag between freezing force and pile deformation. If this lag is not addressed in real time, it can lead to accumulated pile tip deformation, ultimately causing pile fracture and load-bearing failure. This paper proposes a mechanism based on the hysteretic deformation response at the pile tip. It utilizes the thermo-mechanical response factors obtained in previous steps to construct a deformation adjustment index and combines it with real-time monitoring data for deformation response feedback. This effectively solves the problem of nonlinear cumulative failure caused by the instability of permafrost loads, shifting from "rigid frost resistance" to a new approach of "toughness-based frost control," demonstrating forward-looking vision and practical engineering value.

[0151] A model for adjusting the hysteretic deformation at the pile tip is constructed to monitor stress changes in real time. The model is shown below:

[0152]

[0153] in:

[0154] : The pile tip deformation hysteresis adjustment factor of the i-th pile;

[0155] : The instantaneous deformation of the i-th pile at time t;

[0156] : The maximum allowable deformation of the i-th pile;

[0157] when When the load drops to the lower warning limit, the buffer structure at the pile end is activated, such as a compressible pad, a spiral gradient anchor system, or a self-recovering limiting device, to absorb excessive deformation and prevent the pile body from cracking or becoming unstable.

[0158] This model enables the system to dynamically identify and handle high-risk pile locations, preventing structural damage caused by "deformation lag," and giving the entire permafrost pile foundation system active protection capabilities, extending its service life, and improving structural toughness. It is particularly suitable for high-altitude and frigid regions with drastic temperature variations and significant dynamic fluctuations in freezing depth, and has extremely high application value.

[0159] Example 2:

[0160] Reference Figure 2 This is the second embodiment of the present invention, which provides a foundation reinforcement system for precast concrete piles with differentiated pile lengths in frozen soil regions. The system is built based on the reinforcement method described in Embodiment 1, and its functional modules include:

[0161] Partition evaluation module;

[0162] Pile length classification design module;

[0163] Pile length difference control module;

[0164] Pile end structure design module;

[0165] Coupled response evaluation module;

[0166] Pile stress monitoring module.

[0167] In this embodiment, its functional modules are constructed according to the following method:

[0168] First, the system sets up a zoning assessment module, corresponding to step S1, to conduct quantitative analysis of the risk sensitivity of strata in foundation engineering in permafrost regions. This module collects indicators such as water content, geothermal gradient, and fine particle content of strata in various regions to construct a freezing sensitivity factor index system reflecting frost heave potential. It then divides the engineering area into multiple zones with different frost heave characteristics, thus achieving the first step of risk identification based on "zone-specific defense".

[0169] After the partitioning is completed, the system introduces a pile length classification design module, corresponding to step S2. Its function is to construct a multi-level pile length design function based on the frozen sensitivity level in the previous step. This module divides the pile foundation type into a three-level system of "short pile - medium pile - long pile". The design length of each type of pile is mapped to the corresponding sensitivity level, so that the pile length design in different sensitivity level areas can be quantitatively controlled and classified.

[0170] To further avoid the adverse effects of sudden changes in pile length on the structure, the system includes a pile length difference control module, corresponding to step S3. This module constructs a transition adjustment mechanism for pile length between adjacent areas, establishes a function, and optimizes the pile length transition law, thereby reducing the difference in thermal expansion force gradient caused by sudden changes in pile length and improving structural continuity and synergy.

[0171] Subsequently, the system enters the structural response control stage, configuring the pile end structure design module, corresponding to step S4. This module combines the sensitivity level of each pile's zone and the pile length control results to configure pile end structures with differentiated enlarged base diameters. Based on the freezing deformation capacity of the area where the pile end is located, the system sets up enlarged base structures of different sizes and shapes for the pile end, improving the stability of the pile body under freezing expansion forces.

[0172] After the pile end structure is set, the system uses the coupled response evaluation module, corresponding to step S5, to analyze the coupling relationship between the thermal expansion stress on the pile end and the deformation response of the pile body under freezing conditions. This module outputs dynamic response data of the pile body under stress and deformation based on the geometric parameters of the pile end enlarged base structure, providing a basis for the redundant design and safety assessment of the pile body structure.

[0173] Finally, the system is equipped with a pile stress monitoring module, corresponding to step S6, which is used to monitor the stress experienced by the pile in real time during use and adjust the buffer structure or additional constraint device at the pile end based on the monitoring data. This module realizes the closed-loop control function of the system, ensuring that all types of pile structures can maintain operation within the safe threshold under long-term alternating action in the frozen soil environment, thereby improving the reliability and adaptability of the foundation reinforcement system.

[0174] Example 3:

[0175] This embodiment also provides a computer device applicable to a differential pile length foundation reinforcement system and method for precast concrete piles in permafrost regions, including a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to realize the differential pile length foundation reinforcement system and method for precast concrete piles in permafrost regions as proposed in the above embodiment.

[0176] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a differential pile length foundation reinforcement system and method for precast concrete piles in frozen soil regions as proposed in the above embodiments.

[0177] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0178] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0179] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0180] More specific examples (a non-exhaustive list) of computer-readable media include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which programs can be printed, because programs can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0181] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0182] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for reinforcing foundations with differentiated pile lengths of precast concrete piles in permafrost regions, characterized in that, Includes the following steps: S1. Construct a freezing sensitivity factor index to conduct a zonal assessment of the foundation layers with frost heave risk in various engineering areas within the permafrost region. S2. Based on the distribution results of the freezing sensitivity factor, a multi-level pile length design function is constructed to determine the classification of the three-level pile types of "short pile - medium pile - long pile" in each engineering area; S3. Based on the classification results of the three-level pile type, construct a control model for the difference in adjacent pile lengths and optimize the transition law between pile lengths in different regions; S4. Based on the pile length difference control results and combined with the freezing sensitivity of the engineering area where each pile is located, design a pile end structure with a differentiated enlarged base diameter. S5. After determining the enlargement radius of the pile end structure, evaluate the coupling relationship between the thermal expansion stress of the pile end and the response of the pile body structure during the freezing process. S6. Real-time monitoring of pile stress changes, and reverse adjustment of the pile end buffer structure or additional constraint device to achieve effective control of foundation reinforcement for different pile lengths.

2. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in permafrost regions according to claim 1, characterized in that, In step S1, in the permafrost region, a freezing sensitivity factor is established based on factors such as temperature gradient, formation moisture content, and fine particle ratio. The freezing sensitivity factor model is used to assess the frost heave risk of the k-th stratum. in: : The average geothermal gradient of the k-th soil layer; : Moisture content of the k-th soil layer; : The mass fraction of fine particles in the k-th soil layer; : Empirical weighting coefficient, satisfying ; This model is used for frozen sensitive layer identification, based on... The size of the foundation is used to divide the foundation into three sensitive zones: high, medium, and low, and these zones are marked on the foundation layering diagram as a basis for pile length design.

3. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in permafrost regions according to claim 1, characterized in that, In step S2, the constructed multi-level pile length design function is used to calculate the target pile length in the m-th engineering area. The function is shown below: in: : Design pile length for the m-th engineering area; Safety factor, used to amplify the control depth of the sensitive layer; : The freeze sensitivity factor obtained in step S1; The thickness of the k-th soil layer; The set of frost heave risk layers contained in the m-th engineering area; This model transforms the frost heave of the foundation into specific pile length design indicators, realizing the mapping from geological characteristics to structural dimensions and completing the reasonable division of the three pile types: "short pile - medium pile - long pile".

4. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in frozen soil areas according to claim 1, characterized in that, In step S3, the adjacent pile length difference control model optimizes the transition law between different pile lengths from the perspective of pile group layout, in order to reduce stress concentration and differential deformation due to frost heave between piles caused by sudden changes in pile length. The control model for the difference in adjacent pile lengths is shown below: in: : The difference in pile length between adjacent piles i and j; : The calculation results of the lengths of the i-th and j-th adjacent piles obtained through step S2; : The average length of piles within the current pile group area; Transition control coefficient, typically not exceeding 0.25; By limiting the difference in length between adjacent piles, the frost heave deformation coordination of the pile group structure is maintained, and the synergistic effect between piles and soil is enhanced.

5. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in frozen soil areas according to claim 1, characterized in that, In step S4, when designing a pile end structure with a differentiated enlarged bottom diameter, the pile end is kept under balanced stress by adjusting the enlarged bottom diameter, so as to avoid local pile end pull-up or sinking caused by frost heave differences, thereby improving the pile end's resistance to frost heave. A model for the enlarged base radius of the pile tip is constructed to realize the design of pile tip structures with differentiated enlarged base diameters.

6. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in frozen soil areas according to claim 5, characterized in that, The pile tip enlargement radius model is shown below: in: : The radius of the enlarged base of the i-th pile; Standard pile tip radius; : The maximum freezing sensitivity factor in the soil layer traversed by the i-th pile; : The average freezing sensitivity within the i-th engineering region; In areas sensitive to frost heave, the pile tip enlargement is automatically increased to improve frost pull-out resistance and enhance the stability of pile tip bearing capacity.

7. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in frozen soil areas according to claim 1, characterized in that, In step S5, when evaluating the coupling relationship, a thermo-mechanical synergistic control response model is constructed to identify the critical load that the key pile location may bear due to frost heave, and outputs a thermo-mechanical response factor for adjusting the allowable displacement limit of the structure, providing support for actual construction monitoring.

8. The method for reinforcing foundations with differentiated pile lengths of precast concrete piles in frozen soil areas according to claim 7, characterized in that, The thermo-mechanical coordinated regulation response model is as follows: in: : Thermo-mechanical response factor of the i-th pile; : The freezing depth of the area where the i-th pile is located; : Adjustment coefficient, reflecting the effect of freezing on load release; when When the load exceeds the design threshold, a load release structure is used for compensation and release to ensure the integrity of the pile body and provide a quantitative judgment standard.

9. A method for reinforcing foundations with differentiated pile lengths of precast concrete piles in permafrost regions according to claim 1, characterized in that, In step S6, a pile end hysteresis deformation adjustment model is constructed to monitor stress changes in real time. The model is shown below: in: : The pile tip deformation hysteresis adjustment factor of the i-th pile; : The instantaneous deformation of the i-th pile at time t; : The maximum allowable deformation of the i-th pile; when When the temperature drops to the lower warning limit, the buffer structure at the pile tip is activated to absorb excessive deformation and prevent the pile body from cracking or becoming unstable.

10. A foundation reinforcement system for precast concrete piles with differentiated pile lengths in frozen soil regions, constructed based on the reinforcement method described in any one of claims 1-9, characterized in that... The system's functional modules include: Partition evaluation module; Pile length classification design module; Pile length difference control module; Pile end structure design module; Coupled response evaluation module; Pile stress monitoring module.

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