Method for analyzing influence of tunnel blasting on surrounding buildings

Abstract

The invention provides a method for analyzing the influence of tunnel blasting on surrounding buildings. The method comprises the steps of tunnel blasting scheme design, monitoring object selection, numerical simulation analysis, monitoring point position arrangement, monitoring data acquisition, building material point vibration speed representative value selection, blasting vibration safety permission standard selection and feedback construction. The method for acquiring the representative value of the blasting vibration speed of the building influenced by tunnel blasting based on the elevation effect and a numerical simulation method has certain accuracy and safety, and can be widely applied to the field of tunnel blasting vibration control.

Description

Technical Field

[0001] The invention relates to an analysis method for the influence of tunnel blasting on surrounding buildings, and is applicable to the field of tunnel blasting vibration control. Background Art

[0002] Tunnel blasting is a common construction method in urban construction and infrastructure development. However, the impact of tunnel blasting on surrounding buildings cannot be ignored, which may cause structural damage, cracks or even collapse of buildings. Therefore, it is particularly important to study the impact of tunnel blasting on surrounding buildings and develop effective analysis methods.

[0003] Traditional impact analysis methods mainly rely on experience and on-site monitoring, and it is often difficult to comprehensively and accurately assess the potential risks of blasting to the surrounding environment. With the development of computer technology and numerical simulation methods, analysis methods based on advanced technologies such as finite element analysis and dynamic simulation have gradually been introduced. These methods can more accurately simulate the stress propagation and vibration characteristics during blasting and their impact on surrounding buildings, thus providing a scientific basis for engineering design and safety assessment.

[0004] However, there are still some problems with the current conventional practices in the industry. When discussing the impact on surrounding buildings, the current conventional practice is to monitor the blasting vibration velocity of dangerous buildings and control the blasting vibration velocity according to relevant specifications to achieve the purpose of safe construction; however, in terms of monitoring of buildings, the building is a three-dimensional whole, and the monitoring point can only monitor the blasting vibration data of the point. How to ensure that the data measured at the blasting vibration monitoring point can represent the impact of tunnel blasting on the building? At present, the industry's more common practice is to use numerical simulation software such as finite element to simulate the blasting vibration to determine the most unfavorable point, and then arrange the monitoring points in a targeted manner. However, there are serious problems with this approach. On the one hand, numerical simulation has inherent defects. Numerical simulation often assumes that rocks or buildings are isotropic, which is completely different from the actual situation, resulting in inaccurate results of numerical simulation. On the other hand, the building is affected by tunnel blasting, which is manifested as blasting vibration velocity. The blasting vibration velocity has a certain elevation effect, that is, as the height increases, the blasting vibration velocity will also show certain typical characteristics, or the blasting vibration velocity of the building affected by tunnel blasting is related to the elevation. These problems are not reflected in numerical simulation.

[0005] Therefore, how to more accurately obtain the representative value of the blasting vibration velocity of buildings affected by tunnel blasting is a problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the present invention is to solve the problem that a more accurate method for obtaining a representative value of the blasting vibration velocity of a building affected by tunnel blasting is urgently needed, and a method for analyzing the impact of tunnel blasting on surrounding buildings is proposed.

[0007] The purpose of the present invention can be achieved by adopting the following technical solutions:

[0008] A method for analyzing the impact of tunnel blasting on surrounding buildings comprises the following steps:

[0009] S101, tunnel blasting scheme design;

[0010] The design of the tunnel blasting plan includes demarcating the tunnel blasting impact zone according to the actual conditions of surrounding buildings and the requirements of relevant specifications, and implementing a controlled blasting plan in this impact zone. The controlled blasting plan is formulated according to the actual conditions;

[0011] S102, selection of monitoring objects;

[0012] The selection of monitoring objects includes collecting statistics on buildings affected by tunnel blasting, and selecting the most dangerous buildings as monitoring objects according to the distance from the blasting center and the structure and service life of the buildings, wherein the distance from the blasting center is the straight-line distance from the building to the center point of the blasting face;

[0013] S103, analysis of numerical simulations;

[0014] The analysis of the numerical simulation includes using finite element analysis software to perform blasting vibration modeling analysis on the tunnel blasting to obtain the most unfavorable position of the blasting vibration of the most dangerous building, and the selection standard of the most unfavorable position is the position with the largest total blasting vibration speed in the modeling analysis results;

[0015] S104, arrangement of monitoring points;

[0016] The arrangement of the monitoring points includes dividing the monitoring points into Class A and Class B monitoring points. The Class A monitoring points are set to m monitoring points according to the most unfavorable positions obtained, which are recorded as A1~A m The B-type monitoring points are arranged at a fixed height interval h from the bottom to the top of the most dangerous building, with a total of n monitoring points, and the monitoring points are recorded as B1~B n , monitoring point B i (i=1~n) Its corresponding height is H i , H i The calculation formula is as follows:

[0017] H i =(i-1)h, i=1~n (1)

[0018] S105, acquisition of monitoring data;

[0019] The acquisition of the monitoring data includes arranging a blasting vibration meter at the monitoring point before the X-th cycle footage blasting in the tunnel blasting influence area, and obtaining the vibration data of the monitoring point measured by the blasting vibration meter after the tunnel blasting is completed, wherein the vibration data includes the particle vibration velocity and vibration frequency, wherein the A-type monitoring points A1 to A m The particle vibration velocity value is expressed as V A X1 ~V A Xm , Class A monitoring points A1~A m The vibration frequency is represented by f A X1 ~f A Xm , Class B monitoring points B1~B n The particle vibration velocity value is expressed as V B X1 ~V B Xn , Class B monitoring points B1~B n The vibration frequency is represented by f B X1 ~f B Xn ;

[0020] S106, selection of representative values ​​of vibration velocity of building material points;

[0021] The selection of the representative value of the vibration velocity of the building material point includes performing data analysis on the obtained vibration data to obtain the representative value V of the vibration velocity of the material point x ;

[0022] S107, Selection of blasting vibration safety permit standards;

[0023] The blast vibration safety allows the selection of standards, including the vibration frequency f obtained according to A X1 ~f A Xm and f B X1 ~f B Xn As well as the classification of buildings, the vibration velocity control standard V for the building material point of the blasting project of this project is determined in combination with relevant specifications. k ;

[0024] S108, feedback construction;

[0025] The feedback construction includes comparing the particle vibration velocity representative value V xand particle vibration velocity control standard V k , when V x Greater than or equal to V k At this time, it is necessary to adjust the blasting plan in time and adopt a variety of measures to reduce the impact of tunnel blasting on surrounding buildings. The various measures include reducing the amount of explosives and adopting more sections of delayed detonation.

[0026] Furthermore, in the above S106, the particle vibration velocity representative value V x The steps to obtain are:

[0027] a) Constructing a data point set C, wherein the data points are the particle vibration velocity V of the B-type monitoring point B X1 ~V B Xn and the height H of the corresponding monitoring point i Composition, represented by the data point set C = {(H1, V B X1 )、(H2,V B X2 )......(H n , V B Xn )};

[0028] b) performing function fitting according to the data point set C to obtain a fitting curve and a goodness of fit, wherein the goodness of fit is required to be greater than 0.90, otherwise the fitting function model is changed until a fitting curve V(H) that meets the requirements is obtained;

[0029] c) According to the obtained fitting curve V(H), calculate H in [H1,H n ] within the maximum value V max ;

[0030] d) Compare Class A monitoring points A1 to A m The particle vibration velocity value is expressed as V A X1 ~V A Xm and V max and the particle vibration velocity V at the B monitoring point B X1 ~V B Xn , select the maximum value as the representative value V of the particle vibration velocity x .

[0031] The present invention has the following beneficial effects: (1) by combining the elevation effect and the numerical simulation method, the factor of the building height is comprehensively considered, and the representative value of the blasting vibration velocity of the building under the influence of blasting is obtained more scientifically and accurately; (2) by classifying the monitoring points, the present invention can collect the blasting vibration velocity data more comprehensively and more representatively, and obtain more representative representative values ​​of the blasting vibration velocity based on this, while the traditional method is either to arrange the points based on the numerical simulation results or to arrange the monitoring points according to the elevation intervals. It is obvious that the method proposed in this patent is more accurate; (3) in the process of arranging the monitoring points according to the elevation to obtain the monitoring data, the method establishes a fitting curve of the elevation and the monitoring velocity of the monitoring points, and determines the maximum value within the elevation range of the building based on the fitting curve, and determines the representative value of the blasting vibration velocity based on this, which is more accurate and representative. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flow chart of a method for analyzing the impact of tunnel blasting on surrounding buildings according to the present invention;

[0033] Figure 2 It is a fitting curve diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings; it should be understood that the specific embodiments given here are only used to illustrate and explain the present invention and cannot be used to limit the present invention.

[0035] The following is a specific embodiment of a method for analyzing the impact of tunnel blasting on surrounding buildings.

[0036] The tunnel construction project relied on by this embodiment is a tunnel construction project of the East Coast Railway of Malaysia by China Communications Construction Company. The geological conditions of the tunnel are as follows: except for the tunnel entrance section, the overall surrounding rock of the tunnel is in good condition. Preliminary surveys show that the surrounding rock in the tunnel site is mainly granite, and caves are not developed in the area. The surrounding rock of grade II and III in the tunnel body accounts for more than 50%, and the surrounding rock of the inclined shaft is mainly grade IV and V. The surrounding rock has good integrity and low weathering degree. There is abundant precipitation and many surface water systems in the area. For the surrounding rocks of grade IV, V and VI, it is more likely that the surrounding rocks contain fissure water.

[0037] Combination process Figure 1 It can be seen that a method for analyzing the impact of tunnel blasting on surrounding buildings includes the following steps:

[0038] S101, tunnel blasting scheme design;

[0039] The design of the tunnel blasting plan includes demarcating the tunnel blasting impact zone according to the actual conditions of surrounding buildings and the requirements of relevant specifications, and implementing a controlled blasting plan in this impact zone. The controlled blasting plan is formulated according to the actual conditions;

[0040] In this embodiment, the blasting plan is mainly as follows: the types of explosives used in this blasting are No. 2 rock emulsion explosive and rock expanded ammonium nitrate explosive, and non-electric millisecond delay detonators are used for detonation. When arranging the core earth gun holes, the minimum resistance line of the main blasting hole is appropriately increased, and the single hole charge is appropriately reduced; the surrounding eye charge gradually increases from top to bottom, and the resistance line gradually decreases.

[0041] S102, selection of monitoring objects;

[0042] The selection of monitoring objects includes collecting statistics on buildings affected by tunnel blasting, and selecting the most dangerous buildings as monitoring objects according to the distance from the blasting center and the structure and service life of the buildings, wherein the distance from the blasting center is the straight-line distance from the building to the center point of the blasting face;

[0043] In this embodiment, based on the distance from the explosion center and the structure and service life of the building, the most dangerous building is selected and marked as building G as the monitoring object;

[0044] S103, analysis of numerical simulations;

[0045] The analysis of the numerical simulation includes using finite element analysis software to perform blasting vibration modeling analysis on the tunnel blasting to obtain the most unfavorable position of the blasting vibration of the most dangerous building, and the selection standard of the most unfavorable position is the position with the largest total blasting vibration speed in the modeling analysis results;

[0046] In this embodiment, the building G is numerically simulated to obtain the most unfavorable position. In the data simulation, the tunnel surrounding rock material is simulated by the Mohr-Coulomb model, and the state parameter change of the expansion process of the detonation product generated by the explosive blasting is simulated by the JWL state equation. The parameters of the building G concerned are shown in Table 1;

[0047] Table 1. Parameters of numerical simulation of buildings

[0048]

[0049] S104, arrangement of monitoring points;

[0050] The arrangement of the monitoring points includes dividing the monitoring points into Class A and Class B monitoring points. The Class A monitoring points are set to m monitoring points according to the most unfavorable positions obtained, which are recorded as A1~A mThe B-type monitoring points are arranged at a fixed height interval h from the bottom to the top of the most dangerous building, with a total of n monitoring points, and the monitoring points are recorded as B1~B n , monitoring point B i (i=1~n) Its corresponding height is H i , H i The calculation formula is as follows:

[0051] H i =(i-1)h, i=1~n (1)

[0052] In this embodiment, there are 5 Class A points, recorded as A1 to A5, and 7 Class B monitoring points, recorded as B1 to B7;

[0053] S105, acquisition of monitoring data;

[0054] The acquisition of the monitoring data includes arranging a blasting vibration meter at the monitoring point before the X-th cycle footage blasting in the tunnel blasting influence area, and obtaining the vibration data of the monitoring point measured by the blasting vibration meter after the tunnel blasting is completed, wherein the vibration data includes the particle vibration velocity and vibration frequency, wherein the A-type monitoring points A1 to A m The particle vibration velocity value is expressed as V A X1 ~V A Xm , Class A monitoring points A1~A m The vibration frequency is represented by f A X1 ~f A Xm , Class B monitoring points B1~B n The particle vibration velocity value is expressed as V B X1 ~V B Xn , Class B monitoring points B1~B n The vibration frequency is represented by f B X1 ~f B Xn ;

[0055] In this embodiment, a tunnel blasting of a certain cycle footage is selected as an example. Note that during the construction of the cycle footage, the blasting center distance R=22.5m. After the tunnel blasting is completed, the blasting vibration speed and vibration frequency are obtained, wherein the monitoring data are shown in Table 2;

[0056] Table 2 Blasting vibration monitoring data

[0057]

[0058] S106, selection of representative values ​​of vibration velocity of building material points;

[0059] The selection of the representative value of the vibration velocity of the building material point includes performing data analysis on the obtained vibration data to obtain the representative value V of the vibration velocity of the material point x ;

[0060] Furthermore, in the above S106, the particle vibration velocity representative value V x The steps to obtain are:

[0061] a) Constructing a data point set C, wherein the data points are the particle vibration velocity V of the B-type monitoring point B X1 ~V B Xn and the height H of the corresponding monitoring point i Composition, represented by the data point set C = {(H1, V B X1 )、(H2,V B X2 )......(H n , V B Xn )};

[0062] b) performing function fitting according to the data point set C to obtain a fitting curve and a goodness of fit, wherein the goodness of fit is required to be greater than 0.90, otherwise the fitting function model is changed until a fitting curve V(H) that meets the requirements is obtained;

[0063] c) According to the obtained fitting curve V(H), calculate H in [H1,H n ] within the maximum value V max ;

[0064] d) Compare Class A monitoring points A1 to A m The particle vibration velocity value is expressed as V A X1 ~V A Xm and V max and the particle vibration velocity V at the B monitoring point B X1 ~V B Xn , select the maximum value as the representative value V of the particle vibration velocity x .

[0065] In this embodiment, the fitting curve diagram is first obtained as Figure 2 As shown, from Figure 2 It can be seen that the fitting curve expression is: V = 1.267 + 0.097H - 0.005H 2, and the goodness of fit is 0.93173; based on this, the maximum value Vmax at this time is calculated to be: 1.73cm / s, and the height H is 9.7m; finally, the representative value V of the particle vibration velocity is obtained x =1.73cm / s.

[0066] S107, Selection of blasting vibration safety permit standards;

[0067] The blast vibration safety allows the selection of standards, including the vibration frequency f obtained according to A X1 ~f A Xm and f B X1 ~f B Xn As well as the classification of buildings, the vibration velocity control standard V for the building material point of the blasting project of this project is determined in combination with relevant specifications. k ;

[0068] In this embodiment, the building type is a general civil building, the frequency range of the test results is between 10Hz and 50Hz, and the control standard obtained according to the specification "Safety Regulations for Blasting (GB 6722-2014)" is 2.0-2.5cm / s. Combined with the actual situation of this project and the reserved safety margin, the vibration speed control standard V of the material point of the blasting engineering building of this project is finally determined. k =2.0cm / s.

[0069] S108, feedback construction;

[0070] The feedback construction includes comparing the particle vibration velocity representative value V x and particle vibration velocity control standard V k , when V x Greater than or equal to V k At this time, it is necessary to adjust the blasting plan in time and adopt a variety of measures to reduce the impact of tunnel blasting on surrounding buildings. The various measures include reducing the amount of explosives and adopting more sections of delayed detonation.

[0071] In this embodiment, the obtained V x =1.73cm / s <V k =2.0cm / s, so there is no need to adjust the blasting plan.

[0072] In the above embodiment, the present invention discloses a method for analyzing the impact of tunnel blasting on surrounding buildings, including tunnel blasting scheme design, monitoring object selection, numerical simulation analysis, monitoring point arrangement, monitoring data acquisition, selection of representative values ​​of building material point vibration velocity, selection of blasting vibration safety allowable standards and feedback construction. This method is based on the elevation effect and the integrated numerical simulation method to obtain the representative value of the blasting vibration velocity of the building affected by the tunnel blasting, which has certain accuracy and safety and can be widely used in the field of tunnel blasting vibration control.

[0073] The above description is a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for analyzing the impact of tunnel blasting on surrounding buildings, characterized in that The following steps are involved: S101 tunnel blasting scheme design; The tunnel blasting scheme design includes demarcating the tunnel blasting impact zone according to the actual conditions of surrounding buildings and the requirements of relevant specifications, and implementing a controlled blasting scheme in this impact zone. The controlled blasting scheme is formulated according to the actual conditions; S102 Selection of monitoring objects; The selection of monitoring objects includes collecting statistics on buildings affected by tunnel blasting, and selecting the most dangerous buildings as monitoring objects according to the distance from the blasting center and the structure and service life of the buildings, wherein the distance from the blasting center is the straight-line distance from the building to the center point of the blasting face; Analysis of S103 numerical simulation; The analysis of the numerical simulation includes using finite element analysis software to perform blasting vibration modeling analysis on the tunnel blasting to obtain the most unfavorable position of the blasting vibration of the most dangerous building, and the selection standard of the most unfavorable position is the position where the total speed of the blasting vibration is the largest as shown by the modeling analysis results; S104 Arrangement of monitoring points; The arrangement of the monitoring points includes dividing the monitoring points into Class A monitoring points and Class B monitoring points. The Class A monitoring points are set to m monitoring points according to the most unfavorable positions obtained, which are recorded as A1~A m The B-type monitoring points are arranged from the bottom to the top of the most dangerous building at a fixed height interval h, a total of n monitoring points, denoted as B1~B n , monitoring point B i (i=1~n) Its corresponding height is H i , H i Satisfy calculation formula (1); H i =(i-1)h,i=1~n (1) S105 Acquisition of monitoring data; The acquisition of the monitoring data includes arranging a blasting vibration meter at the monitoring point before the X-th cycle footage blasting in the tunnel blasting influence area, and obtaining the vibration data of the monitoring point measured by the blasting vibration meter after the tunnel blasting is completed, wherein the vibration data includes the particle vibration velocity and vibration frequency, wherein the A-type monitoring points A1 to A m The particle vibration velocity is expressed as V A X1 ~V A Xm , Class A monitoring points A1~A m The vibration frequency is represented by f A X1 ~f A Xm , Class B monitoring points B1~B n The particle vibration velocity is expressed as V B X1 ~V B Xn , Class B monitoring points B1~B n The vibration frequency is represented by f B X1 ~f B Xn ; S106 Selection of representative values ​​of vibration velocity of building material points; The selection of the representative value of the vibration velocity of the building material point includes performing data analysis on the obtained vibration data to obtain the representative value V of the vibration velocity of the material point x ; S107 blasting vibration safety allows standard selection; The blast vibration safety allows the selection of standards, including the vibration frequency f obtained according to A X1 ~f A Xm and f B X1 ~f B Xn As well as the classification of buildings, the vibration velocity control standard V for the building material point of the blasting project of this project is determined in combination with relevant specifications. k ; S108 feedback construction; The feedback construction includes comparing the particle vibration velocity representative value V x and particle vibration velocity control standard V k , when V x Greater than or equal to V k At this time, it is necessary to adjust the blasting plan in time and adopt a variety of measures to reduce the impact of tunnel blasting on surrounding buildings. The various measures include reducing the amount of explosives and adopting more sections of delayed detonation.

2. The method for analyzing the impact of tunnel blasting on surrounding buildings according to claim 1, characterized in that: In step S106, the mass point vibration velocity representative value V x The steps to obtain are: a) Constructing a data point set C, wherein the data points are the particle vibration velocity V of the B-type monitoring point B X1 ~V B Xn and the height H of the corresponding monitoring point i Composition, represented by the data point set C = {(H1, V B X1 )、(H2,V B X2 )......(H n , V B Xn )}; b) performing function fitting according to the data point set C to obtain a fitting curve and a goodness of fit, wherein the goodness of fit is required to be greater than 0.90, otherwise the fitting function model is changed until a fitting curve V(H) that meets the requirements is obtained; c) According to the obtained fitting curve V(H), calculate H in [H1,H n ] within the maximum value V max ; d) Compare Class A monitoring points A1 to A m The particle vibration velocity value is expressed as V A X1 ~V A Xm and V max and the particle vibration velocity V at the B monitoring point B X1 ~V B Xn , select the maximum value as the representative value V of the particle vibration velocity x .

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