A soil pressure monitoring pile, a power transmission tower foundation extrusion monitoring method and system

Abstract

A power transmission tower foundation extrusion monitoring method and soil pressure monitoring pile, comprising: setting a tower foundation pile maximum displacement allowable value, initially arranging the positions of the soil displacement detection pile and the soil pressure detection pile according to the unevenness of the pile load, calculating the pressure attenuation coefficient and the displacement attenuation coefficient, optimizing the layout according to the pressure attenuation coefficient and the displacement attenuation coefficient, calculating the absolute value index, the change rate index, the correlation index and the direction difference index of the soil pressure and the displacement, combining the tower foundation pile maximum displacement allowable value and the maximum soil pressure allowable value of the pile side to set the grading warning judgment conditions of each index, judging whether to alarm and the alarm level, the present application shortens the warning response time of the local and the sudden pile load, and reduces the false alarm rate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of tower monitoring, and more particularly relates to a soil pressure monitoring pile, a power transmission tower foundation extrusion monitoring method and system. BACKGROUND

[0002] The power transmission tower foundation long-term bears lateral extrusion caused by external stacking (such as earthwork, equipment, etc.), and its structural stability directly affects the safe operation of the power system. The existing monitoring technology mainly arranges a single-point soil pressure sensor or displacement sensor, collects mechanical or deformation data at a certain position around the foundation, and issues a warning by using simple threshold comparison (such as pressure exceeding a fixed value). Such technology relies on single physical quantity monitoring, does not consider the internal correlation between soil pressure and soil displacement, and does not optimize the spatial distribution of monitoring points for uneven stacking. The soil displacement detection pile is a disclosed technology, which can obtain the displacement of soil at different depths by arranging soil displacement detection piles, but there is currently a lack of a method and system that combines it with the soil pressure pile as a comprehensive criterion to judge the extrusion of the power transmission tower foundation.

[0003] The existing patent CN119756443A discloses a tower foundation stress state early warning system and method, which implants an intelligent anchor rod with an optical fiber sensor in the tower foundation, captures the foundation stress and deformation signals in real time, identifies the state mode and diagnoses the damage by combining the algorithm model, and finally realizes instability hazard early warning. The core basis is that the stress state (such as stress, vibration, deformation) of the tower foundation is directly related to its stability, and these characteristic signals can be captured by high-precision sensing technology, which can reverse the load distribution, transmission path and damage, providing data support for early warning. The technology has the following limitations: the device needs to be directly set on the tower foundation, which is very difficult to achieve in actual production, whether during the foundation construction period or after the completion of the tower; the device is easy to damage the tower foundation; the algorithm only relies on the absolute value of the pressure to make judgments, without considering the dynamic change rate of the data such as sudden increase in pressure in a short time, which is easy to cause early warning lag; no correlation model between pressure and displacement is established, which cannot verify the validity of the data such as abnormal values caused by sensor failure; and the spatial distribution of uneven stacking is not suitable, and single-direction monitoring cannot reflect the all-around characteristics of the foundation stress. SUMMARY

[0004] To solve the problems in the prior art, the present application provides a soil pressure monitoring pile, a power transmission tower foundation extrusion monitoring method and system.

[0005] The present application adopts the following technical solutions.

[0006] The present application provides a soil pressure monitoring pile, a power transmission tower foundation extrusion monitoring method and system.

[0007] The pile body 1-1 is a hollow cubic structure, and a plurality of slot holes 1-2 corresponding to the fixedly installed earth pressure cells 2-3 are formed on the side surface of the pile body 1-1; one side surface of the earth pressure cell is flush with the outer surface of the pile body 1-1, and the opposite side surface of the earth pressure cell 2-3 is provided with a data transmission cable 2-2;

[0008] The bottom assembly 1-3 is a quadrangular pyramid fixed at the bottom of the pile body 1-1; the top assembly 1-4 is a reinforcing structure; the soil pressure monitoring pile is driven into the soil layer at a predetermined depth through the reinforcing structure, the soil pressure at different depths is sensed by the installed earth pressure cells 2-3, and the sensed pressure signals are transmitted through the transmission cable.

[0009] Preferably, the top assembly 1-4 is composed of a top plate 3-1 and a support assembly 3-2, the top plate 3-1 is a cube, the length and width of the top plate 3-1 are greater than the length and width of the pile body 1-1 respectively, and the top plate 3-1 is fixed at the top of the pile body 1-1 through the support assembly 3-2, wherein the support assembly 3-2 comprises four supporting feet and a supporting sleeve, the pile body is fixed in the supporting sleeve, and the center point of the top plate 3-1 coincides with the center point of the pile body 1-1.

[0010] Preferably, the pile body 1-1 is a steel structure, and the bottom assembly 1-3 is a sealed steel cone structure.

[0011] The second aspect of the present application provides a method for monitoring the extrusion of a tower foundation based on the soil pressure monitoring pile of the first aspect of the present application, which comprises the following steps:

[0012] Setting the maximum displacement allowable value of the tower foundation pile, calculating the maximum soil pressure allowable value on the side of the pile and the depth at which the maximum soil pressure allowable value on the side of the pile is located;

[0013] The positions of the soil displacement detection pile and the soil pressure detection pile are preliminarily laid out according to the unevenness of the pile load, the height of the soil displacement detection pile and the soil pressure detection pile is greater than the depth at which the maximum soil pressure allowable value on the side of the pile is located, the soil pressure and displacement at multiple depths measured by the currently laid soil displacement detection pile and soil pressure detection pile are used to calculate the pressure decay coefficient and the displacement decay coefficient, and the layout is optimized according to the pressure decay coefficient and the displacement decay coefficient;

[0014] The soil pressure and displacement at multiple depths measured by the soil displacement detection pile and the soil pressure detection pile after the layout optimization are used to calculate the absolute value index, the change rate index, the correlation index and the direction difference index of the soil pressure and displacement, and the grading warning judgment conditions of each index are set in combination with the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value on the side of the pile to determine whether to issue an alarm and the level of the alarm.

[0015] Preferably, the positions of the soil displacement detection piles and the soil pressure detection piles are preliminarily arranged according to the unevenness of the pile-up loads, specifically:

[0016] Each tower leg of the tower foundation pile is taken as a foundation point, if the height difference between two pile-up loads is greater than a set height difference threshold or the total area of all pile-up loads is less than a set area threshold, a soil displacement detection pile and two soil pressure detection piles are arranged on the line connecting each pile-up load and the nearest foundation point of the corresponding pile-up load, if the distances between the pile-up load and multiple foundation points are the same, a soil displacement detection pile and two soil pressure detection piles are arranged on the line connecting the pile-up load and the center point of the tower foundation pile; the soil displacement detection pile is between the two soil pressure detection piles, and the distances between the soil displacement detection pile and the two soil pressure detection piles are equal;

[0017] Otherwise, a soil displacement detection pile and a soil pressure detection pile are arranged on the line connecting each pile-up load and the nearest foundation point of the corresponding pile-up load, if the distances between the pile-up load and multiple foundation points are the same, a soil displacement detection pile and a soil pressure detection pile are arranged on the line connecting the pile-up load and the center point of the tower foundation pile;

[0018] The distances between all soil displacement detection piles and soil pressure detection piles and the corresponding foundation points are less than a set distance threshold.

[0019] Preferably, the pressure attenuation coefficients and the displacement attenuation coefficients are calculated, and the layout is optimized according to the pressure attenuation coefficients and the displacement attenuation coefficients, specifically:

[0020] The displacement attenuation coefficients between each two depths in each soil displacement detection pile are calculated, and the pressure attenuation coefficients between each two depths in each soil pressure detection pile are calculated.

[0021] For all displacement attenuation coefficients and pressure attenuation coefficients of each soil displacement detection pile and soil pressure detection pile on the line connecting a pile-up load and a foundation point, the sum of all displacement attenuation coefficients and pressure attenuation coefficients is calculated, and the average value is obtained; if the absolute value of the difference between a pressure attenuation coefficient and the average value exceeds a set first threshold, or the absolute value of the difference between two pressure attenuation coefficients exceeds a set second threshold, one more soil displacement detection pile and two soil pressure detection piles are added on the line connecting the corresponding pile-up load and the foundation point.

[0022] Preferably, the displacement attenuation coefficients between each two depths in each soil displacement detection pile are calculated, and the pressure attenuation coefficients between each two depths in each soil pressure detection pile are calculated, specifically:

[0023] ,

[0024]

[0025] in, For the corresponding soil displacement detection pile The depth and the first Displacement attenuation coefficient between depths; For the corresponding earth pressure testing pile, the first The depth and the first Pressure attenuation coefficient between depths; , The first The depth and the first One depth; , These are the corresponding soil displacement detection piles. The depth and the first Displacement at a depth; , These are the corresponding earth pressure testing piles. The depth and the first Earth pressure at a depth of [number] degrees.

[0026] Preferably, the absolute value index, rate of change index, correlation index, and directional difference index are specifically:

[0027] Obtain the soil pressure and displacement measured at different depths by soil displacement monitoring piles and soil pressure monitoring piles along the line connecting different surcharges and foundation points; calculate the... i The first line connecting the load and the foundation point j The average values ​​of all earth pressures and displacements at the given depth are respectively used as the values ​​of the first depth. i The first direction j Earth pressure at a depth and displacement ;

[0028] The absolute value index includes the absolute values ​​of earth pressure and displacement at different depths in different directions; the rate of change index includes the rate of change of earth pressure and displacement at different depths in different directions; the correlation index includes the consistency of pressure-displacement coefficient and attenuation coefficient at different depths in different directions; the pressure-displacement coefficient is the ratio of earth pressure to displacement at a corresponding depth in the corresponding direction; the consistency of the attenuation coefficient is obtained by dividing the difference between the pressure attenuation coefficient and the displacement attenuation coefficient at a corresponding depth in the corresponding direction by the corresponding pressure attenuation coefficient and taking the absolute value; the directional difference index is the maximum directional pressure difference in different directions; the maximum directional pressure difference is the maximum earth pressure at different depths in the corresponding direction minus the minimum earth pressure.

[0029] Preferably, the tiered early warning judgment conditions set by combining the maximum allowable displacement value of the tower foundation pile and the maximum allowable earth pressure value on the pile side to determine whether to issue an alarm and the alarm level are as follows:

[0030] The level of the alarm includes pre-warning, warning and emergency warning;

[0031] The threshold of the absolute value index, the threshold of the change rate index and the threshold of the maximum directional pressure difference in the directional difference index are set according to the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value of the pile side; wherein the threshold of the absolute value index and the threshold of the change rate index both include a pre-warning threshold and a warning threshold;

[0032] The threshold of the consistency of the attenuation coefficient in the correlation index is set; and the adaptive alarm condition of the pressure-displacement coefficient in the correlation index is set;

[0033] When there is an absolute value index or a change rate index greater than or equal to the corresponding pre-warning threshold but less than the corresponding warning threshold, or only one direction of the correlation index meets the corresponding alarm condition, pre-warning is performed; the correlation index meeting the corresponding alarm condition is that the consistency of the attenuation coefficient is greater than or equal to the corresponding threshold or the pressure-displacement coefficient meets the adaptive alarm condition;

[0034] When there is an absolute value index or a change rate index greater than or equal to the corresponding warning threshold, or more than one direction of the correlation index meets the corresponding alarm condition, or only one direction of the directional difference index is greater than or equal to the corresponding threshold, warning is performed;

[0035] If more than one direction of the directional difference index is greater than or equal to the corresponding threshold, emergency warning is performed.

[0036] Preferably, the adaptive alarm condition of the pressure-displacement coefficient in the correlation index is specifically:

[0037]

[0038] In the formula, is the set pressure-displacement coefficient consistency threshold; is the pressure-displacement coefficient of the i-th direction and the j-th depth; i is the pressure-displacement coefficient of the i-th direction and the j-th depth; j is the pressure-displacement coefficient of the i-th direction and the j-th depth; is the j-th depth; j is the j-th depth; is the lateral proportion coefficient of the pile side soil, which is calculated according to the soil layering and the soil type.

[0039] Preferably, if the level of the alarm is pre-warning, the detection frequency of the soil displacement detection pile and the soil pressure detection pile is increased, and it is verified whether the heap loading rate is the same as the set one;

[0040] If the level of the alarm is warning, the heap loading is suspended, and the maximum soil pressure allowable value of the pile side is recalculated;

[0041] If the level of the alarm is an emergency alarm, unload the pile and reinforce the tower foundation pile.

[0042] The third aspect of the present application proposes a power transmission tower foundation extrusion monitoring system based on the power transmission tower foundation extrusion monitoring method of the second aspect of the present application, comprising a maximum value setting module, a layout module and an anomaly detection module, specifically:

[0043] The maximum value setting module is used to set the maximum displacement allowable value of the tower foundation pile, calculate the maximum soil pressure allowable value on the side of the pile and the depth at which the maximum soil pressure allowable value on the side of the pile is located;

[0044] The layout module is used to preliminarily layout the positions of the soil displacement detection pile and the soil pressure detection pile according to the unevenness of the pile load, the height of the soil displacement detection pile and the soil pressure detection pile being greater than the depth at which the maximum soil pressure allowable value on the side of the pile is located, calculate the pressure decay coefficient and the displacement decay coefficient according to the soil pressure and displacement at multiple depths measured by the currently laid soil displacement detection pile and soil pressure detection pile, and optimize the layout according to the pressure decay coefficient and the displacement decay coefficient;

[0045] The anomaly detection module is used to calculate the absolute value index, the change rate index, the correlation index and the direction difference index of the soil pressure and displacement according to the soil pressure and displacement at multiple depths measured by the soil displacement detection pile and the soil pressure detection pile after layout optimization, and combine the grading warning judgment conditions of each index set by the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value on the side of the pile to determine whether to alarm and the level of the alarm.

[0046] The beneficial effects of the present application are that, compared with the prior art, the soil pressure monitoring pile of the present application adds a top assembly and adopts a "high-strength steel + sealed steel cone" structure, can be implanted into the soil layer by hammering, is easy to install and is not easy to damage the foundation body; the multidirectional layout of the detection pile array can cover the unevenly loaded area, the local overrun false alarm rate is significantly reduced, the layout is optimized according to the cooperative verification of pressure and displacement, and the abnormality of the sensor or the distortion of the data is prevented; the hierarchical warning algorithm fuses the change rate index, the correlation index and the direction index, shortens the warning response time for local and sudden pile loads, dynamically adjusts the threshold value in combination with the lateral proportion coefficient of the soil mechanics parameter, and reduces the false alarm rate under different geological conditions such as clay and sandy soil layers. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 It is a front view of the bottom structure of the soil pressure monitoring pile;

[0048] Figure 2 It is an installation structure diagram of the soil pressure cell on the soil pressure monitoring pile;

[0049] Figure 3Structure diagram of top assembly of soil pressure monitoring pile;

[0050] Figure 4 Calculation principle diagram of lateral proportion coefficient of pile side soil of multi-soil layer;

[0051] Figure 5 (a) Calculation principle diagram of calculation width of single pile

[0052] Figure 5 (a) Calculation principle diagram of calculation width of single pile;

[0053] Figure 5 (b) Calculation principle diagram of calculation width of single row pile;

[0054] Figure 6 (a) Force schematic diagram of single pile;

[0055] Figure 6 (b) Force schematic diagram of single row pile;

[0056] Figure 7 Layout schematic diagram of soil displacement detection pile and soil pressure detection pile;

[0057] Figure 8 Flow chart of the present application. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. The embodiments described in the present application are only a part of the embodiments of the present application, but not all the embodiments. All other embodiments obtained by those skilled in the art without creative labor on the basis of the spirit of the present application shall fall within the protection scope of the present application.

[0059] Embodiment 1 of the present application proposes a soil pressure monitoring pile, the bottom front structure of which is shown as Figure 1 , and the installation of the soil pressure box is shown as Figure 2 , specifically comprising a top assembly 1-4, a pile body 1-1, a bottom assembly 1-3, a soil pressure box 2-3, and a data transmission cable 2-2, specifically:

[0060] The pile body 1-1 is a hollow cubic structure, and a plurality of circular grooves 1-2 corresponding to the fixed installation of the soil pressure box 2-3 are opened on one long high side of the pile body 1-1; one side of the soil pressure box is flush with the outer surface of the pile body 1-1, and the data transmission cable 2-2 is installed on the opposite side of the side of the soil pressure box 2-3;

[0061] The bottom assembly 1-3 is a quadrangular pyramid fixed at the bottom of the pile body 1-1; the top assembly 1-4 is a reinforcing structure; the soil pressure monitoring pile is driven into the soil layer at a predetermined depth through the reinforcing structure, the soil pressure at different depths is sensed by the installed soil pressure cell 2-3, and the sensed pressure signal is transmitted through the transmission cable, and the soil pressure cell 2-3 is installed in the circular slot 1-2 through the bolt 2-1.

[0062] Preferably in the embodiment, the top assembly 1-4 is composed of a top plate 3-1 and a support assembly 3-2, the top plate 3-1 is a cube, the length and width of the top plate 3-1 are greater than the length and width of the pile body 1-1 respectively, the top plate 3-1 is fixed at the top of the pile body 1-1 through the support assembly 3-2, wherein the support assembly 3-2 includes four support feet and a support sleeve, the pile body is fixed in the support sleeve, and the center point of the top plate 3-1 coincides with the center point of the pile body 1-1.

[0063] Preferably in the embodiment, the length of the pile body 1-1 is 100 mm, the width is 50 mm; the diameter of the circular slot is 80 mm or 50 mm; the length of the top assembly 1-4 is 400 mm, the width is 360 mm, and the height is 138 mm; the pile body 1-1 is a steel structure, specifically a high-strength steel, and the bottom assembly 1-3 is a sealed steel cone structure.

[0064] It should be noted that the embedding of the soil pressure monitoring pile needs to select an appropriate scheme according to the hardness of the soil to minimize the disturbance to the undisturbed soil and ensure that the monitoring device is consistent with the stress state of the surrounding soil:

[0065] When embedded in conventional soil (non-hard ground):

[0066] When the soil is clay, sand and other non-hard ground, the direct driving method is adopted: the prefabricated monitoring pile is vertically driven to the designed embedding depth along the preset direction (consistent with the line connecting the heaped load and the foundation point) through the hydraulic pile driver. The hammering rate is controlled to be ≤20 blows per minute during the driving process to ensure that the verticality deviation of the pile body is ≤1%. The disturbance range of the undisturbed soil is ≤0.3 m³, the natural stress state of the soil can be maintained, and the authenticity of the data collected by the soil pressure cell and the displacement sensor is guaranteed.

[0067] When embedded in hard soil (including construction waste backfill soil):

[0068] The "drilling-driving composite process" is adopted: (1) Pretreatment: A geological drilling rig (the drill bit diameter is 50mm larger than the outer diameter of the monitoring pile) is used to drill a hole in the preset direction to the initial depth (1 / 3 of the design burial depth and passing through the hard soil layer). Dry soil removal is used during the drilling process (to avoid disturbing the soil with mud); (2) Secondary driving: The monitoring pile is aligned with the center of the hole and driven into the design burial depth by a pile driver; (3) Backfilling and compaction: The gap between the drill hole and the monitoring pile is backfilled with "sand-expansion soil mixed filler" and compacted in layers. After backfilling, the pile is left to stand for 24 hours. The settlement stability is monitored by a pore water pressure gauge (settlement rate ≤ 0.1mm / h) to ensure that the soil pressure around the monitoring pile is consistent with the original soil. Both installation methods require verification of the sensor status after completion: the zero drift of the soil pressure cell is ≤ 0.5kPa and the initial reading deviation of the displacement sensor is ≤ 0.1mm before the monitoring stage can begin.

[0069] like Figure 8 As shown, Embodiment 1 of the present invention proposes a method for monitoring the compression of transmission tower foundations using soil pressure monitoring piles, comprising:

[0070] S1. Set the maximum allowable displacement of the tower foundation piles, and calculate the maximum allowable earth pressure on the pile side and the depth at which the maximum allowable earth pressure on the pile side is located.

[0071] The maximum allowable displacement of the foundation piles in this embodiment Set to 6mm.

[0072] The calculation of the allowable value of the maximum earth pressure on the pile side and the depth at which the allowable value of the maximum earth pressure on the pile side is located is as follows:

[0073] (1) Deformation coefficient of pile in soil :

[0074]

[0075] In the formula For the bending stiffness of the pile, the value can be taken as follows: (The value can be taken as follows for reinforced concrete piles of towers subjected to short-term loads). For reinforced concrete piles of towers bearing long-term loads at corners and at terminals, the following can be taken: ; The elastic modulus of concrete; The moment of inertia of the pile section; This refers to the lateral proportionality coefficient of the soil along the pile. This is the calculated width of the pile.

[0076] Lateral proportionality coefficient of soil along pile The value is taken based on the soil type within the calculated depth of the pile's penetration, such as... Figure 4 As shown, when calculating depth When there are several very different soil layers, their properties can be calculated using the following formula. value:

[0077] When there are two layers of soil with different properties within the depth of the pile:

[0078]

[0079] When there are three layers of soil with different properties within the depth of the pile:

[0080]

[0081] , , are the lateral proportionality coefficients of the first, second and third soil layers, respectively; , , are the depths of the first, second and third soil layers.

[0082] The calculated width of the pile b is specifically:

[0083] As shown in Fig. a, the calculated width of a single pile with a circular cross-section Figure 5 may be calculated according to the following formula: b

[0084] When the diameter of the pile is less than 1.5 times the depth of the first soil layer, the calculated width of the pile is:

[0085]

[0086] When the diameter of the pile is greater than 1.5 times the depth of the first soil layer, the calculated width of the pile is:

[0087]

[0088] As shown in Fig. b, a single row of piles composed of several piles in a plane perpendicular to the plane of the acting force, the calculated width of a single pile is: Figure 5 b

[0089] When the diameter of the pile is less than 1.5 times the depth of the first soil layer, the calculated width of the pile is:

[0090]

[0091] When the diameter of the pile is greater than 1.5 times the depth of the first soil layer, the calculated width of the pile is:

[0092]

[0093] In the above formulae, is the diameter of the pile; is the number of piles in the Y-axis direction; is the influence coefficient of each pile in the Y-axis direction, which is determined as follows:​​​

[0094] When or , ;

[0095] When , take ;

[0096] When , take

[0097] wherein, is the pile spacing of the number of piles.

[0098] For any depth h below the ground, the lateral displacement , the rotation angle , the lateral earth pressure , the shear force and the bending moment of a single pile under lateral load are calculated as follows:

[0099]

[0100]

[0101]

[0102]

[0103]

[0104] In the above formulae, the shear force at the ground, , is the design horizontal force acting on the pile top; is the number of piles in the Y-axis direction; is the bending moment at the ground; is the deformation coefficient of the pile in the soil; is the calculated width of the pile; , , , , , , , , , are all dimensionless calculation coefficients.

[0105] The coefficient is obtained as follows:

[0106]

[0107] Also for dimensionless calculation coefficient, according to Look up table to get the corresponding maximum conversion depth , Divided by The depth of the maximum allowable value of the soil pressure on the pile side ;

[0108] The maximum allowable value of the soil pressure on the pile side Is:

[0109]

[0110] The maximum allowable value of the soil pressure on the pile side is calculated, and the maximum allowable value of the soil pressure on the pile side Should meet the following requirements:

[0111] When The position ;

[0112]

[0113] When The position ;

[0114]

[0115] In the above formula, The height of the pile; φ, c The internal friction angle and cohesion of the soil on the pile side, respectively; γ The effective unit weight of the soil on the pile side; The design safety factor, for the tower bearing short-term load, take ;

[0116] S2, the positions of the soil displacement detection pile and the soil pressure detection pile are preliminarily laid out according to the unevenness of the pile load, the heights of the soil displacement detection pile and the soil pressure detection pile are greater than the depth of the maximum allowable value of the soil pressure on the pile side, the soil pressure and displacement at multiple depths measured by the currently laid soil displacement detection pile and soil pressure detection pile are used to calculate the pressure attenuation coefficient and the displacement attenuation coefficient, and the layout is optimized according to the pressure attenuation coefficient and the displacement attenuation coefficient.

[0117] As Figure 7 Illustrated, the positions of the soil displacement detection pile and the soil pressure detection pile are preliminarily laid out according to the unevenness of the pile load, specifically:

[0118] Each leg of the tower foundation pile is treated as a foundation point. If the height difference between two loads is greater than a set height difference threshold or the total area of ​​all loads is less than a set area threshold, then a soil displacement detection pile and two earth pressure detection piles are set on the line connecting each load to the nearest foundation point. If the load is at the same distance from multiple foundation points, then a soil displacement detection pile and two earth pressure detection piles are set on the line connecting the load to the center point of the tower foundation pile. The soil displacement detection pile is located between the two earth pressure detection piles, and the distance between the soil displacement detection pile and the two earth pressure detection piles is equal.

[0119] Otherwise, a soil displacement detection pile and an earth pressure detection pile shall be set on the line connecting each load and the nearest foundation point to the corresponding load. If the load is at the same distance from multiple foundation points, a soil displacement detection pile and an earth pressure detection pile shall be set on the line connecting the load and the center point of the tower foundation pile.

[0120] All soil displacement and soil pressure monitoring piles are located less than the set distance threshold from their corresponding foundation points.

[0121] In this preferred embodiment, the calculation of the pressure attenuation coefficient and the displacement attenuation coefficient, and the layout optimization based on the pressure attenuation coefficient and the displacement attenuation coefficient, specifically involves:

[0122] Calculate the displacement attenuation coefficient between every two depths in each soil displacement monitoring pile; calculate the pressure attenuation coefficient between every two depths in each earth pressure monitoring pile;

[0123] For all displacement and pressure attenuation coefficients of soil displacement and pressure monitoring piles on the line connecting a surcharge and a foundation point, calculate the sum of all displacement and pressure attenuation coefficients and obtain the average value. If the absolute value of the difference between a pressure attenuation coefficient and the average value exceeds a set first threshold, or the absolute value of the difference between two pressure attenuation coefficients exceeds a set second threshold, then add one more soil displacement monitoring pile and two more soil pressure monitoring piles on the corresponding line connecting the surcharge and foundation point.

[0124] In this preferred embodiment, the calculation of the displacement attenuation coefficient between every two depths in each soil displacement detection pile and the calculation of the pressure attenuation coefficient between every two depths in each earth pressure detection pile are specifically as follows:

[0125] ,

[0126]

[0127] in, For the corresponding soil displacement detection pile The depth and the first a displacement attenuation coefficient between the first depth and the second depth; a pressure attenuation coefficient between the first depth and the second depth of the corresponding soil pressure detection pile; a pressure attenuation coefficient between the first depth and the second depth of the corresponding soil pressure detection pile; a pressure attenuation coefficient between the first depth and the second depth of the corresponding soil pressure detection pile; the first depth and the second depth, respectively; the first depth and the second depth, respectively; the displacement of the first depth and the second depth of the corresponding soil displacement detection pile, respectively; the displacement of the first depth and the second depth of the corresponding soil displacement detection pile, respectively; the soil pressure of the first depth and the second depth of the corresponding soil pressure detection pile, respectively. the soil pressure of the first depth and the second depth of the corresponding soil pressure detection pile, respectively.

[0128] S3, according to the soil pressure and displacement of multiple depths measured by the soil displacement detection pile and the soil pressure detection pile after layout optimization, calculate the absolute value index, the change rate index, the correlation index and the direction difference index of the soil pressure and displacement, combine the grading warning judgment conditions of each index set by the maximum displacement allowed value of the tower foundation pile and the maximum soil pressure allowed value of the pile side, to judge whether to alarm and the level of the alarm.

[0129] In the embodiment, the absolute value index, the change rate index, the correlation index and the direction difference index are specifically:

[0130] obtain the soil pressure and displacement measured at different depths by each soil displacement detection pile and soil pressure detection pile on the connecting line of different pile loads and foundation points; calculate the average value of all soil pressure and displacement at the first depth on the connecting line of the first pile load and foundation point, as the soil pressure and displacement of the first direction and the first depth, respectively; i j i j

[0131] The absolute value index includes the absolute value of the soil pressure and the absolute value of the displacement at different depths and different directions; the change rate index includes the change rate of the soil pressure and the change rate of the displacement at different depths and different directions; the correlation index includes the consistency of the pressure-displacement coefficient and the attenuation coefficient at different depths and different directions; the pressure-displacement coefficient is the ratio of the soil pressure and the displacement at the corresponding depth and direction; the attenuation coefficient consistency is the difference value of each pressure attenuation coefficient and displacement attenuation coefficient at the corresponding depth and direction divided by the corresponding pressure attenuation coefficient, taking the absolute value; the direction difference index is the maximum directional pressure difference of different directions; the maximum directional pressure difference is the maximum soil pressure minus the minimum soil pressure in the corresponding direction and different depths.​​​​​​​​​​​​

[0132] Preferably, the embodiment sets the grading early warning judgment conditions of each index of the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value of the pile side, judges whether to perform an alarm and the level of the alarm, and specifically:

[0133] The level of the alarm includes pre-warning, warning, and emergency warning.

[0134] The absolute value index threshold value, the change rate index threshold value, and the threshold value of the maximum directional pressure difference in the directional difference index are set according to the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value of the pile side; the pre-warning threshold value and the warning threshold value are included in the absolute value index threshold value and the change rate index threshold value.

[0135] The threshold value of the consistency of the attenuation coefficient in the correlation index is set, and the adaptive alarm condition of the pressure-displacement coefficient in the correlation index is set.

[0136] Specifically, the pre-warning threshold value of the soil pressure absolute value is 0.8 times the maximum soil pressure allowable value of the pile side , the warning threshold value is 0.95 times the maximum soil pressure allowable value of the pile side ; the pre-warning threshold value of the displacement absolute value is 0.8 times the maximum displacement allowable value of the tower foundation pile, and the warning threshold value is 0.95 times the maximum displacement allowable value of the tower foundation pile; the pre-warning threshold value of the soil pressure change rate is , the warning threshold value is , the pre-warning threshold value of the displacement change rate is , and the warning threshold value is , is the height of the pile; the threshold value of the consistency of the attenuation coefficient is 20%.

[0137] When the absolute value index or the change rate index is greater than or equal to the corresponding pre-warning threshold value but less than the corresponding warning threshold value, or only one direction of the correlation index meets the corresponding alarm condition, pre-warning is performed; the correlation index meeting the corresponding alarm condition is that the consistency of the attenuation coefficient is greater than or equal to the corresponding threshold value or the pressure-displacement coefficient meets the adaptive alarm condition.

[0138] When the absolute value index or the change rate index is greater than or equal to the corresponding warning threshold value, or more than one direction of the correlation index meets the corresponding alarm condition, or only one direction of the directional difference index is greater than or equal to the corresponding threshold value, warning is performed.

[0139] If more than one direction of the directional difference index is greater than or equal to the corresponding threshold value, emergency warning is performed.

[0140] Preferably, the embodiment sets the adaptive alarm condition of the pressure-displacement coefficient in the correlation index, and specifically:

[0141]

[0142] in the formula, is a set pressure-displacement coefficient consistency threshold, and the embodiment is 30%; is the pressure-displacement coefficient of the first direction and the first depth; i is the pressure-displacement coefficient of the first direction and the first depth; j is the pressure-displacement coefficient of the first direction and the first depth; is the first depth; j is the first depth; is a lateral proportion coefficient of the pile side soil, obtained according to soil layering and soil type calculation.

[0143] Preferably, if the level of the alarm is a pre-warning, the detection frequency of the soil displacement detection pile and the soil pressure detection pile is increased to verify whether the stack loading rate is the same as the set value;

[0144] If the level of the alarm is a warning, the stack loading is suspended, and the maximum soil pressure allowable value of the pile side is recalculated;

[0145] If the level of the alarm is an emergency warning, the stack is unloaded, and the tower foundation pile is reinforced.

[0146] Embodiment 3 of the present application proposes a power transmission tower foundation extrusion monitoring system based on the power transmission tower foundation extrusion monitoring method described in Embodiment 2 of the present application, which comprises a maximum value setting module, a layout module and an abnormality detection module, specifically:

[0147] The maximum value setting module is used to set the maximum displacement allowable value of the tower foundation pile, calculate the maximum soil pressure allowable value of the pile side and the depth at which the maximum soil pressure allowable value of the pile side is located;

[0148] The layout module is used to preliminarily layout the positions of the soil displacement detection pile and the soil pressure detection pile according to the stack loading unevenness, the height of the soil displacement detection pile and the soil pressure detection pile is greater than the depth at which the maximum soil pressure allowable value of the pile side is located, the soil pressure and displacement at multiple depths measured by the currently laid soil displacement detection pile and soil pressure detection pile are used to calculate the pressure attenuation coefficient and the displacement attenuation coefficient, and the layout is optimized according to the pressure attenuation coefficient and the displacement attenuation coefficient;

[0149] The abnormality detection module is used to calculate the absolute value index, the change rate index, the correlation index and the direction difference index of the soil pressure and displacement at multiple depths measured by the soil displacement detection pile and the soil pressure detection pile after layout optimization, and to determine whether to alarm and the level of the alarm in combination with the grading pre-warning judgment conditions of each index set by the maximum displacement allowable value of the tower foundation pile and the maximum soil pressure allowable value of the pile side.

[0150] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application but not to limit it, and although the present application has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered in the protection scope of the claims of the present application.

Claims

1. A method for monitoring the compression of transmission tower foundations based on a soil pressure monitoring pile, characterized in that, include: Set the maximum allowable displacement of the tower foundation piles, and calculate the maximum allowable earth pressure on the pile side and the depth at which the maximum allowable earth pressure on the pile side is located. The locations of soil displacement detection piles and earth pressure detection piles are initially arranged according to the unevenness of the surcharge. The height of the soil displacement detection piles and earth pressure detection piles is greater than the depth where the maximum allowable earth pressure on the pile side is located. Based on the earth pressure and displacement measured at various depths by the currently arranged soil displacement detection piles and earth pressure detection piles, the pressure attenuation coefficient and displacement attenuation coefficient are calculated. The layout is optimized based on the pressure attenuation coefficient and displacement attenuation coefficient. Based on the soil pressure and displacement measured at various depths by the soil displacement detection piles and soil pressure detection piles after the layout optimization, the absolute value index, rate of change index, correlation index and directional difference index of soil pressure and displacement are calculated. Combined with the graded early warning judgment conditions of each index set by the maximum allowable displacement value of the tower foundation pile and the maximum allowable soil pressure value of the pile side, it is determined whether to issue an alarm and the level of the alarm. The locations of the soil displacement monitoring piles and earth pressure monitoring piles are initially arranged according to the unevenness of the surcharge, specifically as follows: Each leg of the tower foundation pile is treated as a foundation point. If the height difference between two loads is greater than a set height difference threshold or the total area of ​​all loads is less than a set area threshold, then a soil displacement detection pile and two earth pressure detection piles are set on the line connecting each load to the nearest foundation point. If the load is at the same distance from multiple foundation points, then a soil displacement detection pile and two earth pressure detection piles are set on the line connecting the load to the center point of the tower foundation pile. The soil displacement detection pile is located between the two earth pressure detection piles, and the distance between the soil displacement detection pile and the two earth pressure detection piles is equal. Otherwise, a soil displacement detection pile and an earth pressure detection pile shall be set on the line connecting each load and the nearest foundation point to the corresponding load. If the load is at the same distance from multiple foundation points, a soil displacement detection pile and an earth pressure detection pile shall be set on the line connecting the load and the center point of the tower foundation pile. The soil pressure monitoring pile includes a top component (1-4), a pile body (1-1), a bottom component (1-3), an earth pressure box (2-3), and a data transmission cable (2-2). The pile body (1-1) is a hollow cubic structure. Several slots (1-2) are opened on the side of the pile body (1-1) to fix and install the earth pressure box (2-3). One side of the earth pressure box is flush with the outer surface of the pile body (1-1), and the data transmission cable (2-2) is installed on the opposite side of the earth pressure box (2-3). The bottom component (1-3) is a square pyramid, fixed to the bottom of the pile body (1-1); the top component (1-4) is a reinforcing structure; the soil pressure monitoring pile is driven into the soil layer at a predetermined depth through the reinforcing structure, and the soil pressure at different depths is sensed by the soil pressure box (2-3) and the sensed pressure signal is transmitted through the transmission cable.

2. The method for monitoring the extrusion of transmission tower foundations according to claim 1, characterized in that: The top component (1-4) consists of a top plate (3-1) and a support component (3-2). The top plate (3-1) is a cube, and the length and width of the top plate (3-1) are greater than the length and width of the pile body (1-1), respectively. The top plate (3-1) is fixed to the top of the pile body (1-1) by the support component (3-2). The support component (3-2) includes four support legs and a support sleeve. The pile body is fixed inside the support sleeve. The center point of the top plate (3-1) coincides with the center point of the pile body (1-1).

3. The method for monitoring the extrusion of transmission tower foundations according to claim 1 or 2, characterized in that: The pile body (1-1) is a steel structure, and the bottom component (1-3) is a sealed steel cone structure.

4. The method for monitoring the extrusion of transmission tower foundations according to claim 1, characterized in that: The calculation of the pressure attenuation coefficient and displacement attenuation coefficient, and the layout optimization based on the pressure attenuation coefficient and displacement attenuation coefficient, specifically involves: Calculate the displacement attenuation coefficient between every two depths in each soil displacement monitoring pile; calculate the pressure attenuation coefficient between every two depths in each earth pressure monitoring pile; For all displacement and pressure attenuation coefficients of soil displacement and pressure monitoring piles on the line connecting a surcharge and a foundation point, calculate the sum of all displacement and pressure attenuation coefficients and obtain the average value. If the absolute value of the difference between a pressure attenuation coefficient and the average value exceeds a set first threshold, or the absolute value of the difference between two pressure attenuation coefficients exceeds a set second threshold, then add one more soil displacement monitoring pile and two more soil pressure monitoring piles on the corresponding line connecting the surcharge and foundation point.

5. The method for monitoring the extrusion of transmission tower foundations according to claim 4, characterized in that: The calculation of the displacement attenuation coefficient between every two depths in each soil displacement monitoring pile and the calculation of the pressure attenuation coefficient between every two depths in each earth pressure monitoring pile are specifically as follows: ， in, For the corresponding soil displacement detection pile The depth and the first Displacement attenuation coefficient between depths; For the corresponding earth pressure testing pile, the first The depth and the first Pressure attenuation coefficient between depths; , The first The depth and the first One depth; , These are the corresponding soil displacement detection piles. The depth and the first Displacement at a depth; , These are the corresponding earth pressure testing piles. The depth and the first Earth pressure at a depth of [number] degrees.

6. The method for monitoring the extrusion of transmission tower foundations according to claim 5, characterized in that: The absolute value indicators, rate of change indicators, correlation indicators, and directional difference indicators are specifically as follows: Obtain the soil pressure and displacement measured at different depths by soil displacement monitoring piles and soil pressure monitoring piles along the line connecting different surcharges and foundation points; calculate the... i The first line connecting the load and the foundation point j The average values ​​of all earth pressures and displacements at the given depth are respectively used as the values ​​of the first depth. i The first direction j Earth pressure at a depth and displacement ; The absolute value index includes the absolute values ​​of earth pressure and displacement at different depths in different directions; the rate of change index includes the rate of change of earth pressure and displacement at different depths in different directions; the correlation index includes the consistency of pressure-displacement coefficient and attenuation coefficient at different depths in different directions; the pressure-displacement coefficient is the ratio of earth pressure to displacement at a corresponding depth in the corresponding direction; the consistency of the attenuation coefficient is obtained by dividing the difference between the pressure attenuation coefficient and the displacement attenuation coefficient at a corresponding depth in the corresponding direction by the corresponding pressure attenuation coefficient and taking the absolute value; the directional difference index is the maximum directional pressure difference in different directions; the maximum directional pressure difference is the maximum earth pressure at different depths in the corresponding direction minus the minimum earth pressure.

7. The method for monitoring the extrusion of transmission tower foundations according to claim 6, characterized in that: The tiered early warning judgment conditions for each index, which are set based on the maximum allowable displacement value of the tower foundation pile and the maximum allowable earth pressure value on the pile side, determine whether to issue an alarm and the alarm level, specifically as follows: Alarm levels include warning, alert, and emergency alert; The threshold values ​​for absolute value indicators, rate of change indicators, and maximum directional pressure difference indicators are set based on the maximum allowable displacement of the tower foundation piles and the maximum allowable earth pressure on the pile side. Among them, the threshold values ​​for absolute value indicators and rate of change indicators include both early warning thresholds and alarm thresholds. Set a threshold for consistency of attenuation coefficients in the correlation indicators; set adaptive alarm conditions for pressure-displacement coefficients in the correlation indicators. An early warning is issued when an absolute value indicator or rate of change indicator is greater than or equal to the corresponding warning threshold but less than the corresponding alarm threshold, or when only one direction of the correlation indicator meets the corresponding alarm condition; the correlation indicator meets the corresponding alarm condition when the attenuation coefficient consistency is greater than or equal to the corresponding threshold or the pressure-displacement coefficient meets the adaptive alarm condition. An alarm is triggered when an absolute value indicator or rate of change indicator is greater than or equal to the corresponding alarm threshold, or when more than one direction correlation indicator meets the corresponding alarm condition, or when only one direction difference indicator is greater than or equal to the corresponding threshold. If the directional difference index in more than one direction is greater than or equal to the corresponding threshold, an emergency alarm will be issued.

8. The method for monitoring the extrusion of transmission tower foundations according to claim 7, characterized in that: The adaptive alarm condition for the pressure-displacement coefficient in the set correlation index is specifically as follows: In the formula, The set pressure-displacement coefficient consistency threshold; For the first i The first direction j Pressure-displacement coefficient at depth; For the first j One depth; This is the lateral proportionality coefficient of the soil along the pile. Calculated based on soil stratification and soil type.

9. The method for monitoring the extrusion of transmission tower foundations according to claim 8, characterized in that: If the alarm level is warning, increase the detection frequency of soil displacement detection piles and soil pressure detection piles, and verify whether the surcharge loading rate is the same as the setting. If the alarm level is alarm, then surcharge loading is suspended and the maximum allowable value of earth pressure on the pile side is recalculated. If the alarm level is an emergency alarm, the load is unloaded and the tower foundation piles are reinforced.

10. A transmission tower foundation extrusion monitoring system based on the transmission tower foundation extrusion monitoring method according to any one of claims 1-9, comprising a maximum value setting module, a layout module, and an anomaly detection module, characterized in that: Maximum value setting module: used to set the maximum allowable displacement of the tower foundation pile, calculate the maximum allowable earth pressure on the pile side and the depth at which the maximum allowable earth pressure on the pile side is located; Layout module: Used to initially arrange the positions of soil displacement detection piles and earth pressure detection piles according to the unevenness of the load. The height of the soil displacement detection piles and earth pressure detection piles is greater than the depth where the maximum allowable value of the earth pressure on the pile side is located. Based on the earth pressure and displacement measured at various depths by the currently arranged soil displacement detection piles and earth pressure detection piles, the pressure attenuation coefficient and displacement attenuation coefficient are calculated, and the layout is optimized based on the pressure attenuation coefficient and displacement attenuation coefficient. Anomaly Detection Module: Based on the soil pressure and displacement measured at various depths by the soil displacement detection piles and soil pressure detection piles after layout optimization, it calculates the absolute value index, rate of change index, correlation index, and directional difference index of soil pressure and displacement. Combined with the graded early warning judgment conditions set for each index of the tower foundation pile maximum allowable displacement value and the pile side maximum allowable soil pressure value, it determines whether to issue an alarm and the alarm level.

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