High-speed rail proximity socketed foundation pile construction influence area division method based on multi-factor coupling analysis

Abstract

The invention discloses a high-speed rail proximity socketed foundation pile construction influence area division method based on multi-factor coupling analysis, and particularly relates to the technical field of civil engineering. The method comprises the following steps: determining influence parameters, namely a horizontal distance parameter, a burial depth parameter and a construction parameter; assigning values to the influence parameters; a multi-factor coupling object objective function of the influence level of the newly-built pile foundation on the existing pile foundation of the adjacent high-speed rail is constructed; calculating an influence value of the newly-built pile foundation; based on the early warning value, the alarm value and the control value of track deformation and pier deformation of the adjacent high-speed rail existing bridge caused by the newly-built pile foundation, the influence grade and the division standard of the newly-built pile foundation on the adjacent high-speed rail existing bridge are set; and according to the influence grade and the division standard, the influence grade corresponding to the influence value of the newly-built foundation pile is judged. By the adoption of the technical scheme, the problem that in the prior art, the influence range of a newly-built high-speed rail bridge pile foundation adjacent to a high-speed rail on an existing bridge foundation cannot be divided is solved, and the safety of high-speed rail construction is improved.

Description

Technical Field

[0001] This invention relates to the field of civil engineering technology, and in particular to a method for delineating the influence zone of high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis. Background Technology

[0002] As a core component of high-speed railway civil engineering, high-speed railway bridges have become an indispensable part of the transportation industry. The ever-increasing demand for travel has led to a proliferation of bridges located near, intersecting, and crossing each other. Ensuring the safety and stability of bridges under complex conditions is paramount during construction, primarily manifested in the impact of new bridge construction on the structural stability of nearby existing bridges. In particular, the disturbance to the soil during the construction of new bridge pile foundations can cause displacement and settlement of existing bridge pile foundations, compromising the stability and safety of the existing structure. Furthermore, the influence of construction machinery and methods during bridge construction contributes to the complexity and diversity of bridge engineering in my country.

[0003] Bridge engineering in my country is characterized by its diverse types and complex construction. High-speed railway lines require strict control over longitudinal deformation and settlement. High-speed railway bridge foundations generally employ rock-socketed pile foundations, which effectively address the overall stability of the bridge and the safety of high-speed train traffic. When constructing pile foundations for new bridges adjacent to high-speed railways, the safety of existing bridges is affected by factors such as construction machinery, construction methods, and the passage of existing high-speed trains. This can alter the bearing capacity and deformation characteristics of the existing bridge pile foundations, potentially leading to longitudinal deformation and settlement exceeding permissible values, thus posing new risks to the operation of existing high-speed railway lines.

[0004] Therefore, it is necessary to analyze and classify the impact range of the pile foundations of newly built high-speed railway bridges on the existing bridge foundations in order to reduce the impact of the pile foundations of newly built bridges on the operational safety of adjacent high-speed railway lines. Summary of the Invention

[0005] This invention aims to provide a method for delineating the impact area of ​​high-speed railway adjacent rock-embedded foundation pile construction based on multi-factor coupling analysis. It solves the problem in the prior art that it is impossible to delineate the impact range of the pile foundation of a newly built high-speed railway bridge on the existing bridge foundation. Through this invention, the impact of the construction stage of the pile foundation project of the newly built high-speed railway bridge on the traffic of the adjacent existing high-speed railway bridge can be evaluated, so as to meet the needs of the construction of the new bridge project and the safety of the adjacent existing bridge.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: a method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis, comprising the following steps:

[0007] S1. Determine the influencing parameters: the horizontal distance parameter is the influence of the horizontal distance of the new pile foundation on the existing pile foundation, the burial depth parameter is the influence of the burial depth of the new pile foundation on the existing pile foundation, and the construction parameter is the influence of the construction of the new pile foundation on the existing pile foundation. The weights of the horizontal distance parameter, burial depth parameter, and construction parameter are α = 0.5, β = 0.2, and γ = 0.3, respectively.

[0008] S2. Assign values ​​to the influence parameters of step S1. The horizontal distance parameter is assigned the value M = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, the burial depth parameter is assigned the value N = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, and the construction parameter is assigned the value Q = {1, 0.5, 0.25, 0.125}.

[0009] S3. Construct the objective function R of a multi-factor coupled object for the impact level of the newly constructed pile foundation on the existing pile foundation of the adjacent high-speed railway, R = αM + βN + γQ;

[0010] S4. Calculate the impact value of the newly built pile foundation by using the impact parameters and objective function of the newly built pile foundation;

[0011] S5. Based on the early warning value, alarm value and control value of the deformation of the track and pier of the existing high-speed railway bridge caused by the new pile foundation, set the impact level and classification standard of the new pile foundation on the existing high-speed railway bridge.

[0012] S6. Referring to the impact level and classification criteria in step S5, determine the impact level corresponding to the impact value of the newly built foundation pile in step S4.

[0013] Furthermore, the horizontal distance parameters in step S3 are as follows: Level 1 is a pile foundation spacing of less than or equal to 3 times the pile diameter; Level 2 is a pile foundation spacing between 3 and 5 times the pile diameter; and Level 3 is a pile foundation spacing greater than 5 times the pile diameter.

[0014] Furthermore, the burial depth parameters for step S3 are as follows: Level 1 is when the pile tip of the new pile foundation is lower than the compression range of the pile tip of the existing pile foundation; Level 2 is when the pile tip of the new pile foundation is within the range of 1 / 3 of the pile length above the pile tip of the existing pile foundation; Level 3 is when the pile tip of the new pile foundation is more than 1 / 3 of the pile length above the pile tip of the existing pile foundation.

[0015] Furthermore, the construction parameters for step S3 are as follows: Level 1 is that the new pile foundation is drilled using impact drilling; Level 2 is that the new pile foundation is drilled using rotary drilling or auger drilling without wall protection; Level 3 is that the new pile foundation is drilled using rotary drilling or auger drilling with mud wall protection; Level 4 is that the new pile foundation is drilled using rotary drilling or auger drilling with steel casing wall protection.

[0016] Furthermore, the impact level of the newly constructed pile foundations on the existing pile foundations of the adjacent high-speed railway in step S1 is set as follows:

[0017] Level I: If the longitudinal deformation and settlement deformation of the existing bridge are within the cumulative warning value range, the high-speed train can pass at the design speed.

[0018] Level II: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative warning value, but are less than the cumulative alarm value. High-speed trains need to reduce their speed to pass.

[0019] Level III: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative alarm value, but are less than the control value, which has affected the passage of high-speed trains;

[0020] Level IV: The longitudinal deformation and settlement deformation of the existing bridge exceed the control values, which seriously affects the safety of high-speed train operation.

[0021] Furthermore, the standard division method for step S2 is as follows: The "Technical Specification for Safety Monitoring of Construction Near Operating Railway Lines" stipulates that: for the vertical and horizontal displacement deformation of high-speed railway tracks, the vertical displacement of ballastless track bridge piers, the horizontal displacement of the top and bottom transverse tracks of ballastless track bridge piers, and the horizontal displacement of the top and bottom longitudinal tracks of ballastless track bridge piers, the cumulative monitoring warning values, cumulative alarm values, and control values ​​are ±1.2mm, ±1.6mm, and ±2.0mm, respectively; for the vertical displacement of ballasted track bridge piers, the horizontal displacement of the top and bottom transverse tracks of ballasted track bridge piers, and the horizontal displacement of the top and bottom longitudinal tracks of ballasted track bridge piers, the cumulative monitoring warning values, cumulative alarm values, and control values ​​are ±1.8mm, ±2.4mm, and ±3.0mm, respectively.

[0022] Based on the cumulative warning value to meet the design operating speed of high-speed trains, the ratio of cumulative warning value to cumulative control value is 1:1.33, and the ratio of control value to cumulative warning value is 1:1.67. The classification standard for the impact level of newly constructed pile foundations on adjacent existing high-speed railway bridges is set as follows:

[0023]

[0024] The intervals in the above formula correspond to Level I, Level II, Level III, and Level IV of the influence level, respectively, from top to bottom.

[0025] Compared with existing technologies, the beneficial effects of this solution are:

[0026] This invention provides a method for zoning the impact of high-speed railway adjacent rock-embedded foundation pile construction based on multi-factor coupling analysis. This method comprehensively considers the impact of newly constructed pile foundations on existing high-speed railway pile foundations under the main influencing factors during actual construction. Based on the actual operational needs of existing high-speed railway bridges, it allows for more targeted selection of the horizontal distance between the new and existing pile foundations, the embedment depth of the new and existing pile foundations, and the construction method of the new pile foundations. This enables precise control of data such as longitudinal deformation and settlement deformation of existing high-speed railway bridges, reducing the impact of the new bridge pile foundations on the operational safety of adjacent high-speed railway lines. For new bridge projects with zoning levels IV and III, a feasibility analysis is conducted, and a construction plan is formulated, comprehensively considering the horizontal distance between the new and existing pile foundations, the embedment depth of the new and existing pile foundations, and the construction method of the new pile foundations. For new bridge projects with zoning level II, the actual operational needs of existing high-speed railway bridges and the specific conditions of the new pile foundations should be considered, including the selection of the spatial distance between the new and existing bridge pile foundations, the construction method of the new bridge pile foundations, and the construction machinery. Attached Figure Description

[0027] Figure 1 This is a flowchart of the method for dividing the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis, which is a method of the present invention. Detailed Implementation

[0028] The present invention will be further described in detail below through specific embodiments:

[0029] Example

[0030] like Figure 1 As shown, the method for delineating the influence zone of high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis includes the following steps:

[0031] S1. Determine the influencing parameters: The horizontal distance parameter is the influence of the horizontal distance of the new pile foundation on the existing pile foundation; the burial depth parameter is the influence of the burial depth of the new pile foundation on the existing pile foundation; and the construction parameter is the influence of the construction of the new pile foundation on the existing pile foundation. The weights of the horizontal distance parameter, burial depth parameter, and construction parameter are α = 0.5, β = 0.2, and γ = 0.3, respectively.

[0032] Among these factors, the drilling of new pile foundations reduces the bearing capacity and safety of adjacent pile foundations. Due to the complex and ambiguous relationships between various factors, an expert evaluation method was used to determine the weights of the horizontal distance parameter α, the burial depth parameter β, the construction parameter γ, the horizontal distance parameter M, the burial depth parameter N, and the construction parameter Q. Experts were selected from high-speed railway design units, construction units, supervision units, testing units, and engineering sections, with three units selected from each unit type and five experts randomly chosen. The sum of the weights of the horizontal distance parameter α, the burial depth parameter β, and the construction parameter γ was set to 1. The horizontal distance parameter M was categorized by level and its assigned value was also set to 1. The sum of the assigned values ​​of the burial depth parameter N and the construction parameter Q were also set to 1. All weights and influence parameter assignments given by the experts were collected and organized, and normal distribution analysis was used to determine the assigned values ​​of the horizontal distance parameter α, the burial depth parameter β, the construction parameter γ, the horizontal distance parameter M, the burial depth parameter N, and the construction parameter Q.

[0033] The agreed-upon terms for the expert survey are as follows: (1) The sum of the horizontal distance parameter weight α, the burial depth parameter weight β, and the construction parameter weight γ is 1. The weight values ​​given by the experts are less than 1.0 and are expressed as even numbers with two decimal places. (2) The parameter selection for the first, second, third, and fourth levels of the horizontal distance parameter M, burial depth parameter N, and construction parameter Q is as follows: the first level is 1.0, and the parameters for the second, third, and fourth levels decrease progressively. The parameters given by the experts for the second and third levels are even numbers with two decimal places, and the parameters given by the experts for the fourth level are even numbers with three decimal places. The standard deviation and mean of the relevant expert evaluation data and normal analysis are shown in Tables 1-4 below. According to the analysis of the expert evaluation data, the standard deviation of the normal distribution is less than 0.05, and the average values ​​of the horizontal distance parameter weight α, the burial depth parameter weight β, the construction parameter weight γ, the horizontal distance parameter M, the burial depth parameter N, and the construction parameter Q are selected.

[0034] Table 1. Expert Analysis Table of Weights

[0035]

[0036] Table 2. Expert Analysis Table of Horizontal Distance Parameters

[0037]

[0038]

[0039] Table 3. Expert Analysis Table of Burial Depth Parameters

[0040] Level 1 Level 2 Level 3 Expert 1 1 0.52 0.22 Expert 2 1 0.44 0.3 Expert 3 1 0.56 0.18 Expert 4 1 0.54 0.2 Expert 5 1 0.5 0.3 Expert 6 1 0.46 0.28 Expert 7 1 0.5 0.26 Expert 8 1 0.5 0.25 Expert 9 1 0.56 0.2 Expert 10 1 0.48 0.22 Expert 11 1 0.48 0.26 Expert 12 1 0.46 0.28 Expert 13 1 0.5 0.26 Expert 14 1 0.54 0.24 Expert 15 1 0.46 0.3 average value 1 0.5 0.25 Standard deviation 0 0.0378 0.0391

[0041] Table 4. Expert Analysis Table of Construction Parameters

[0042] Level 1 Level 2 Level 3 Level 4 Expert 1 1 0.54 0.22 0.12 Expert 2 1 0.42 0.28 0.14 Expert 3 1 0.56 0.22 0.12 Expert 4 1 0.52 0.22 0.12 Expert 5 1 0.5 0.26 0.12 Expert 6 1 0.48 0.28 0.14 Expert 7 1 0.5 0.25 0.12 Expert 8 1 0.5 0.25 0.14 Expert 9 1 0.54 0.24 0.12 Expert 10 1 0.48 0.22 0.1 Expert 11 1 0.48 0.26 0.12 Expert 12 1 0.46 0.26 0.16 Expert 13 1 0.5 0.26 0.14 Expert 14 1 0.56 0.24 0.08 Expert 15 1 0.46 0.3 0.14 average value 1 0.5 0.25 0.125 Standard deviation 0 0.0393 0.0246 0.0192

[0043] In this embodiment, the horizontal distance parameter is as follows: Regarding the horizontal distance between the newly built pile foundation and the existing pile foundation, the influence of the horizontal distance between the newly built pile foundation and the existing pile foundation is divided according to the degree of mutual influence between the pile foundations: Level 1 is when the spacing between the pile foundations is less than or equal to 3 times the pile diameter; Level 2 is when the spacing between the pile foundations is between 3 and 5 times the pile diameter; Level 3 is when the spacing between the pile foundations is greater than 5 times the pile diameter.

[0044] Burial depth parameters: Regarding the burial depth of newly constructed pile foundations and existing pile foundations, the influence of the burial depth of newly constructed pile foundations on existing pile foundations is classified according to the relative position of the burial depth of newly constructed pile foundations and existing pile foundations as follows: Level 1 is when the pile tip of the newly constructed pile foundation is lower than the compression range of the pile tip of the existing pile foundation; Level 2 is when the pile tip of the newly constructed pile foundation is within the range of the pile tip depth of the existing pile foundation to 1 / 3 of the pile length above the pile tip of the existing pile foundation; Level 3 is when the pile tip of the newly constructed pile foundation is more than 1 / 3 of the pile length above the pile tip of the existing pile foundation.

[0045] Construction parameters: Regarding the construction methods and machinery for new pile foundations, they are classified into three types according to the pile foundation drilling method: impact drilling, rotary drilling, and auger drilling. They are also classified into three types according to the hole protection method: steel casing, mud slurry, and no casing. The impact of new pile foundation construction on existing pile foundations is categorized as follows: Level 1: New pile foundations using impact drilling; Level 2: New pile foundations using rotary drilling or auger drilling without casing; Level 3: New pile foundations using rotary drilling or auger drilling with mud slurry casing; Level 4: New pile foundations using rotary drilling or auger drilling with steel casing.

[0046] S2. Assign values ​​to the influence parameters of step S1. The horizontal distance parameter is assigned the value M = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, the burial depth parameter is assigned the value N = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, and the construction parameter is assigned the value Q = {1, 0.5, 0.25, 0.125}.

[0047] S3. Construct the objective function R of a multi-factor coupled object for the impact level of the newly constructed pile foundation on the existing pile foundation of the adjacent high-speed railway, R = αM + βN + γQ;

[0048] S4. Calculate the impact value of the newly built pile foundation by using the impact parameters and objective function of the newly built pile foundation;

[0049] S5. Based on the warning value, alarm value, and control value of the deformation of the track and piers of the existing high-speed railway bridge caused by the new pile foundation, the influence level K of the new pile foundation on the existing high-speed railway bridge is set, K = {Level I, Level II, Level III, Level IV} and the classification standard; In this embodiment, the influence level of the new pile foundation on the existing high-speed railway bridge is determined according to the longitudinal deformation and settlement deformation index of the existing high-speed railway bridge.

[0050] The impact level is set as follows:

[0051] Level I: If the longitudinal deformation and settlement deformation of the existing bridge are within the cumulative warning value range, the high-speed train can pass at the design speed.

[0052] Level II: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative warning value, but are less than the cumulative alarm value. High-speed trains need to reduce their speed to pass.

[0053] Level III: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative alarm value, but are less than the control value, which has affected the passage of high-speed trains;

[0054] Level IV: The longitudinal deformation and settlement deformation of the existing bridge exceed the control values, which seriously affects the safety of high-speed train operation.

[0055] The classification criteria are as follows:

[0056] The "Technical Specification for Safety Monitoring of Construction Adjacent to Operating Railway Lines" stipulates that the cumulative monitoring values ​​for vertical and horizontal displacement deformation of high-speed railway tracks, vertical displacement of ballastless track bridge piers, horizontal displacement of the top and bottom transverse tracks of ballastless track bridge piers, and horizontal displacement of the top and bottom longitudinal tracks of ballastless track bridge piers are ±1.2mm, ±1.6mm, and ±2.0mm, respectively. For vertical displacement of ballasted track bridge piers, horizontal displacement of the top and bottom transverse tracks of ballasted track bridge piers, and horizontal displacement of the top and bottom longitudinal tracks of ballasted track bridge piers, the cumulative monitoring values ​​for vertical displacement of ballast track bridge piers, horizontal displacement of the top and bottom transverse tracks of ballasted track bridge piers, and horizontal displacement of the top and bottom longitudinal tracks of ballasted track bridge piers are ±1.8mm, ±2.4mm, and ±3.0mm, respectively.

[0057] Based on the cumulative warning value to meet the design operating speed of high-speed trains, the ratio of cumulative warning value to cumulative control value is 1:1.33, and the ratio of control value to cumulative warning value is 1:1.67. The classification standard for the impact level of newly constructed pile foundations on adjacent existing high-speed railway bridges is set as follows:

[0058]

[0059] The intervals in the above formula correspond to Level I, Level II, Level III, and Level IV of the influence level, respectively, from top to bottom.

[0060] S6. Referring to the impact level and classification criteria in step S5, determine the impact level corresponding to the impact value of the newly built foundation pile in step S4.

[0061] The aforementioned technical solution features multi-factor coupling, different influence weights, and different safety responses. It proposes factors involving the horizontal distance, depth, and construction method between new and existing pile foundations. Based on the pile foundation bearing capacity and construction disturbance characteristics, it proposes horizontal distance parameters M, depth parameters N, construction parameters Q, and corresponding classifications. Through multi-domain expert evaluation, the weights of horizontal distance, depth, and construction, as well as the assigned values ​​for horizontal distance parameters M, depth parameters N, and construction parameters Q, are determined. A multi-factor coupling objective function R is constructed to describe the degree of impact of new pile foundations on the safety of existing bridges. Based on the cumulative early warning value, cumulative alarm value, and control value of deformation of adjacent existing bridges in the current technical standard "Technical Specification for Safety Monitoring of Construction Near Operating Railway Lines" (TB10314-2021), a method for classifying the impact level of new pile foundation construction on the safety of existing bridges is proposed. Finally, the calculated value of the multi-factor coupling objective function R is compared with the classification standard for impact level to determine the impact level and select an appropriate construction method.

[0062] Application examples:

[0063] Taking the construction of a new bridge pile foundation project adjacent to an existing high-speed railway bridge as an example, the implementation of this invention will be further described in detail. The pile foundations of piers 17#-23# of a certain high-speed railway super-large bridge are adjacent to the existing high-speed railway line. The pile lengths are 50m-55m, the pile diameter is 1.2m, and the pile ends are located approximately 5m above the pile ends of the existing railway line pile foundations. The minimum net distance between the newly constructed pile foundation 20-6# and the existing pile foundation is 3.5m, and the minimum net distance between the newly constructed pile foundation 21-4# and the existing pile foundation is 4.1m. The newly constructed pile foundations 19-6#, 20-4#, and 21-6#, which are within 6m of the existing railway line pile foundations, are constructed using rotary drilling and steel casing. The newly constructed pile foundations 20-1#, 20-12#, and 21-7#, which are more than 10m away from the existing railway line pile foundations, are constructed using rotary drilling and mud slurry casing.

[0064] The specific implementation process is as follows:

[0065] Based on the horizontal distance between the proposed new pile foundation and the existing pile foundation, and the construction method of the new pile foundation, the pile foundation grade of this new bridge project is divided into two cases for separate calculation. One case is where the new pile foundation is within 6m of the existing pile foundation, using rotary drilling and steel casing for wall protection; the other case is where the new pile foundation is more than 10m away from the existing pile foundation, using rotary drilling and mud slurry wall protection.

[0066] S1. The evaluation indicators for the influencing factors are as follows: the horizontal distance parameter is the influence of the horizontal distance of the new pile foundation on the existing pile foundation; the burial depth parameter is the influence of the burial depth of the new pile foundation on the existing pile foundation; and the construction parameter is the influence of the construction of the new pile foundation on the existing pile foundation. The weights of the evaluation indicators for the influencing factors are α = 0.5, β = 0.2, and γ = 0.3, respectively.

[0067] (1) Horizontal distance parameter

[0068] The minimum net distance between the newly constructed pile foundation 20-6# and the existing pile foundation is 3.5m, which is less than 3 times the pile diameter, and M is determined to be Level 1; the net distance between the newly constructed pile foundations 21-4#, 19-6#, 20-4#, and 21-6# and the existing pile foundations is between 3 and 5 times the pile diameter, and M is determined to be Level 2; the distance between the newly constructed pile foundations 20-1#, 20-12#, and 21-7# and the existing line pile foundations is greater than 10m, which is more than 5 times the pile diameter, and M is determined to be Level 3.

[0069] (2) Burial depth parameters

[0070] The pile tips of the newly constructed pile foundations 19-6#, 20-1#, 20-4#, 20-6#, 20-12#, 21-4#, 21-6#, and 21-7# are located approximately 5m above the pile tips of the existing piles. The pile tips of the newly constructed pile foundations are located within the range of the depth of the existing pile foundation pile tip to 1 / 3 of the pile length above the existing pile foundation pile tip. N is determined to be level two.

[0071] (3) Construction parameters

[0072] The construction of new pile foundations 20-6#, 21-4#, 19-6#, 20-4#, and 21-6# will be carried out using rotary drilling with steel casing for wall protection, and Q will be determined as level four; the construction of new pile foundations 20-1#, 20-12#, and 21-7# will be carried out using rotary drilling with mud slurry for wall protection, and Q will be determined as level three.

[0073] Step S4: Consider the degree of influence of each evaluation indicator and assign values ​​to the evaluation indicators under different degrees of influence.

[0074] S2, the horizontal distance parameter is assigned as M = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, the burial depth parameter is assigned as N = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, and the construction parameter is assigned as Q = {1, 0.5, 0.25, 0.125}.

[0075] (1) Assigning values ​​to the horizontal distance parameter

[0076] New 20-6# pile foundation, M=1;

[0077] New pile foundations for piles 19-6#, 20-4#, 21-4#, and 21-6# are constructed, with M=0.5.

[0078] New pile foundations 20-1#, 20-12#, and 21-7# are to be constructed, with M=0.25.

[0079] (2) Assigning burial depth parameters

[0080] New pile foundations will be constructed for piles 19-6#, 20-1#, 20-4#, 20-6#, 20-12#, 21-4#, 21-6#, and 21-7#, with N = 0.5.

[0081] (3) Assignment of construction parameters

[0082] New pile foundations 19-6#, 20-4#, 20-6#, 21-4#, and 21-6# are constructed with Q=0.125; new pile foundations 20-1#, 20-12#, and 21-7# are constructed with Q=0.25.

[0083] S3. Construct a multi-factor coupled objective function R for the impact level of the newly constructed pile foundation on the existing pile foundation of the adjacent high-speed railway, R = 0.5M + 0.2N + 0.3Q.

[0084] S4. Substitute the parameters α, β, γ, M, N, and Q of the project into the objective function in step 5, and calculate the R value of the newly constructed pile foundation project, which are as follows:

[0085] (1) Construction of new pile foundation No. 19-6

[0086] R=0.5x0.5+0.2x0.5+0.3x0.125=0.388;

[0087] (2) New 20-1# pile foundation

[0088] R=0.5x0.25+0.2x0.5+0.3x0.25=0.300;

[0089] (3) New 20-4# pile foundation

[0090] R=0.5x0.5+0.2x0.5+0.3x0.125=0.388;

[0091] (4) New 20-6# pile foundation

[0092] R=0.5x1+0.2x0.5+0.3x0.125=0.638;

[0093] S5. Based on the early warning value, alarm value and control value of the deformation of the track and pier of the existing high-speed railway bridge caused by the new pile foundation, set the impact level and classification standard of the new pile foundation on the existing high-speed railway bridge.

[0094] The level of impact is:

[0095] Level I: If the longitudinal deformation and settlement deformation of the existing pile foundation are within the cumulative warning value range, the high-speed train can pass at the design speed.

[0096] Level II: The longitudinal deformation and settlement deformation of the existing pile foundation reach the cumulative warning value, but are less than the cumulative alarm value, and the high-speed train needs to reduce its speed to pass.

[0097] Level III: The longitudinal deformation and settlement deformation of the existing pile foundation have reached the cumulative alarm value, but are less than the control value, which has already affected the passage of high-speed trains;

[0098] Level IV: The longitudinal deformation and settlement deformation of the existing pile foundations exceed the control values, which seriously affects the safety of high-speed train operation.

[0099] The classification criteria are as follows:

[0100]

[0101] Based on the above formula, the levels are divided into Level I, Level II, Level III, and Level IV from top to bottom.

[0102] The R-values ​​of the newly constructed high-speed railway bridge pile foundations (S6, 19-6#, 20-1#, 20-4#, 20-6#, 20-12#, 21-4#, 21-6#, and 21-7#) range from 0.263 to 0.638. Based on the classification standards, these newly constructed high-speed railway bridge pile foundations have a relatively weak impact on the operational safety of adjacent existing high-speed railway bridges, classified as Level I. The longitudinal deformation and settlement deformation monitoring are within the cumulative warning value range, and high-speed trains can pass at the design speed.

[0103] The above are merely embodiments of the present invention, and common knowledge such as specific structures and / or characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for delineating the influence zone of high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis, characterized in that... Includes the following steps: S1. Determine the influencing parameters: the horizontal distance parameter is the influence of the horizontal distance of the new pile foundation on the existing pile foundation, the burial depth parameter is the influence of the burial depth of the new pile foundation on the existing pile foundation, and the construction parameter is the influence of the construction of the new pile foundation on the existing pile foundation. The weights of the horizontal distance parameter, burial depth parameter, and construction parameter are α = 0.5, β = 0.2, and γ = 0.3, respectively. S2. Assign values ​​to the influence parameters of step S1. The horizontal distance parameter is assigned the value M = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, the burial depth parameter is assigned the value N = {Level 1, Level 2, Level 3} = {1, 0.5, 0.25}, and the construction parameter is assigned the value Q = {1, 0.5, 0.25, 0.125}. S3. Construct the objective function R of a multi-factor coupled object for the impact level of the newly constructed pile foundation on the existing pile foundation of the adjacent high-speed railway, R = αM + βN + γQ; S4. Calculate the impact value of the newly built pile foundation by using the impact parameters and objective function of the newly built pile foundation; S5. Based on the early warning value, alarm value and control value of the deformation of the track and pier of the existing high-speed railway bridge caused by the new pile foundation, set the impact level and classification standard of the new pile foundation on the existing high-speed railway bridge. S6. Referring to the impact level and classification criteria in step S5, determine the impact level corresponding to the impact value of the newly built foundation pile in step S4.

2. The method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis according to claim 1, characterized in that: The horizontal distance parameters for step S3 are as follows: Level 1 is a pile foundation spacing of less than or equal to 3 times the pile diameter; Level 2 is a pile foundation spacing between 3 and 5 times the pile diameter; and Level 3 is a pile foundation spacing greater than 5 times the pile diameter.

3. The method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis according to claim 1, characterized in that: The burial depth parameters for step S3 are as follows: Level 1 is when the pile tip of the new pile foundation is lower than the compression range of the pile tip of the existing pile foundation; Level 2 is when the pile tip of the new pile foundation is within the range of 1 / 3 of the pile length above the pile tip of the existing pile foundation; Level 3 is when the pile tip of the new pile foundation is more than 1 / 3 of the pile length above the pile tip of the existing pile foundation.

4. The method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis according to claim 1, characterized in that: Construction parameters for step S3: Level 1: New pile foundations are drilled using impact drilling; Level 2: New pile foundations are drilled using rotary drilling or auger drilling without wall protection; Level 3: New pile foundations are drilled using rotary drilling or auger drilling with mud wall protection; Level 4: New pile foundations are drilled using rotary drilling or auger drilling with steel casing wall protection.

5. The method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis according to claim 1, characterized in that: The impact level of the newly constructed pile foundation on the existing pile foundation of the adjacent high-speed railway in step S1 is set as follows: Level I: If the longitudinal deformation and settlement deformation of the existing bridge are within the cumulative warning value range, the high-speed train can pass at the design speed. Level II: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative warning value, but are less than the cumulative alarm value. High-speed trains need to reduce their speed to pass. Level III: The longitudinal deformation and settlement deformation of the existing bridge have reached the cumulative alarm value, but are less than the control value, which has affected the passage of high-speed trains; Level IV: The longitudinal deformation and settlement deformation of the existing bridge exceed the control values, which seriously affects the safety of high-speed train operation.

6. The method for delineating the influence area of ​​high-speed railway near-surface rock-embedded foundation pile construction based on multi-factor coupling analysis according to claim 5, characterized in that: The standard division method for step S2 is as follows: The "Technical Specification for Safety Monitoring of Construction Near Operating Railway Lines" stipulates that the cumulative monitoring values ​​for vertical and horizontal displacement deformation of high-speed railway tracks, vertical displacement of ballastless track bridge piers, horizontal displacement of the top and bottom transverse tracks of ballastless track bridge piers, and horizontal displacement of the top and bottom longitudinal tracks of ballastless track bridge piers are ±1.2mm, ±1.6mm, and ±2.0mm, respectively; for vertical displacement of ballasted track bridge piers, horizontal displacement of the top and bottom transverse tracks of ballasted track bridge piers, and horizontal displacement of the top and bottom longitudinal tracks of ballasted track bridge piers, the cumulative monitoring values ​​for warning, alarm, and control are ±1.8mm, ±2.4mm, and ±3.0mm, respectively. Based on the cumulative warning value to meet the design operating speed of high-speed trains, the ratio of cumulative warning value to cumulative control value is 1:1.33, and the ratio of control value to cumulative warning value is 1:1.

67. The classification standard for the impact level of newly constructed pile foundations on adjacent existing high-speed railway bridges is set as follows: The intervals in the above formula correspond to Level I, Level II, Level III, and Level IV of the influence level, respectively, from top to bottom.

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