A partitioned blasting construction analysis method for tunnel crossing cultural relic protection area

Abstract

The application discloses a kind of partitioned blasting construction analysis methods for tunnel crossing cultural relic protection zone, it is related to blasting construction technical field, including establishing three-dimensional geological model and cultural relic three-dimensional model, the finite element modal analysis environment of cultural relic protection zone blasting construction is constructed;Under the finite element modal analysis environment of cultural relic protection zone blasting construction, the limit damage threshold of cultural relic and cultural relic dangerous node are determined by applying cultural relic resonance frequency, according to the limit damage threshold of cultural relic and cultural relic resonance frequency, the initial limit value of blasting vibration safety speed is calculated, and the blasting vibration safety speed correction limit value is obtained by correcting the initial limit value of blasting vibration safety speed according to the cultural relic vulnerability evaluation index calculated by the vulnerability influence data of cultural relic;According to the three-level risk area of cultural relic vulnerability evaluation index, the output is calculated by using the Sadovsky formula as the vibration attenuation model for the explosive quantity of buffer zone and safety zone.It is ensured that construction vibration is within the safety threshold, and the risk of cultural relic damage is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blasting construction, in particular to a partition blasting construction analysis method for tunnel crossing cultural relic protection areas. BACKGROUND

[0002] With the rapid development of infrastructure construction in China, tunnel engineering is widely used in the fields of transportation, water conservancy, etc. However, in the densely populated area of historical and cultural heritage, tunnel construction faces the dual challenges of cultural relic protection and engineering safety. The traditional blasting construction technology is difficult to accurately control the vibration, which is easy to cause irreversible damage to the adjacent cultural relics. For example, in 2020, a subway tunnel construction caused cracks in a Ming Dynasty brick tower, which exposed the limitations of traditional methods. Currently, the fixed limit value (such as 0.5-1.5 cm / s) of the “Blasting Safety Regulations” (GB 6722-2014) is generally used, but the differences in material, age and structural characteristics of cultural relics are not considered. For example, the difference in vibration resistance between wooden buildings and brick and stone sites can be more than 3 times, and the unified standard is easy to cause “overprotection” or “insufficient protection”.

[0003] In the Chinese invention application with the application publication number CN117670092A, a coal mine blasting data analysis system based on data analysis is disclosed, which includes a coal mine information acquisition module, a blastability grade analysis module, a filling area determination module, a coal mine blasting analysis module, a regional charge amount analysis module, a feedback terminal and a database. By obtaining the natural parameters of each coal mine sub-region, and preliminarily analyzing each coal mine sub-region, the corresponding blastability grade of each coal mine sub-region is obtained, the corresponding each initial screening filling area of the target coal mine is determined comprehensively, and the corresponding required blasting charge amount of the target coal mine is analyzed. Finally, the maximum bearing charge amount corresponding to each initial screening filling area is analyzed, and the corresponding each filling area of the target coal mine is finally determined.

[0004] In the above invention application, the maximum bearing charge amount corresponding to each initial screening filling area is analyzed, but only the blastability analysis of the rock stratum is considered. In the blasting across the cultural relic protection area, if only the blastability of the rock stratum is considered without considering the protection of cultural relics, the structure of cultural relics may be damaged or collapsed. Once the structure of cultural relics is severely damaged, the repair work will become extremely complex and expensive. For example, the cracks in the brick masonry structure may be accompanied by brick cracking and mortar falling, which requires professional technology and a large amount of resources, and the thousand-year historical information carried by the cultural relics may be permanently lost with the collapse of the structure. After the destruction of the mortise and tenon joint of the ancient building, the research data such as construction techniques and decorative arts will be difficult to restore, and after the collapse, large-scale reconstruction is needed, but the original materials and techniques may have been lost. Ignoring the protection of cultural relics will cause economic, legal and social losses, and may delay the project progress.

[0005] Therefore, the present application provides a partition blasting construction analysis method for tunnel crossing cultural relic protection areas. SUMMARY

[0006] (1) Technical problems solved

[0007] In view of the deficiencies of the prior art, the present application provides a partitioned blasting construction analysis method for tunneling through a cultural relic protection zone. The present application determines the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic by applying the cultural relic resonance frequency under the finite element modal analysis environment of the blasting construction of the cultural relic protection zone, calculates the initial limit value Xz of the blasting vibration safety speed according to the limit damage threshold A of the cultural relic and the cultural relic resonance frequency f, and corrects the initial limit value Xz of the blasting vibration safety speed according to the cultural relic vulnerability influence data calculates the cultural relic vulnerability evaluation index Cr, corrects the initial limit value Xz of the blasting vibration safety speed to obtain the corrected limit value Jz of the blasting vibration safety speed, quantifies the cultural relic vulnerability and the vibration response, realizes accurate correction of the safety threshold, provides all-round optimization for the blasting construction, and achieves the triple promotion of safety, efficiency and cost, thereby solving the technical problems recorded in the background art.

[0008] (2) Technical solutions

[0009] To achieve the above purpose, the present application is implemented by the following technical solutions: a partitioned blasting construction analysis method for tunneling through a cultural relic protection zone, comprising the following steps:

[0010] Collecting geological structure point cloud data and cultural relic body structure point cloud data, establishing a three-dimensional geological model and a three-dimensional cultural relic model, importing the three-dimensional geological model and the three-dimensional cultural relic model into the same analysis environment, converting the frequency response function curve into a frequency domain excitation, applying it to the cultural relic model, and constructing a finite element modal analysis environment for the blasting construction of the cultural relic protection zone;

[0011] Under the finite element modal analysis environment of the blasting construction of the cultural relic protection zone, the cultural relic resonance frequency is applied, the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic are determined, the initial limit value Xz of the blasting vibration safety speed is calculated according to the limit damage threshold A of the cultural relic and the cultural relic resonance frequency f, and the initial limit value Xz of the blasting vibration safety speed is corrected according to the cultural relic vulnerability influence data calculating the cultural relic vulnerability evaluation index Cr, correcting the initial limit value Xz of the blasting vibration safety speed to obtain the corrected limit value Jz of the blasting vibration safety speed;

[0012] According to the cultural relic vulnerability evaluation index Cr, three risk zones are delineated, and for the buffer zone and the safety zone explosive quantity, the Sadaovsky formula is used as the vibration attenuation model to calculate the output.

[0013] Further, the geological radar and the unmanned aerial oblique photography are used to collect the geological structure point cloud data and the cultural relic body structure point cloud data, and to establish the three-dimensional geological model and the three-dimensional cultural relic model.

[0014] Further, the vibration exciter is connected to the non-sensitive part of the cultural relic through a flexible connecting rod, and a three-axis acceleration sensor is arranged at a key node of the cultural relic. The electromagnetic vibration exciter applies a linear sweep of 0.1-50 Hz at a sweep rate of 1 Hz / s, and the acceleration amplitude is ≤0.05g. After aligning the frequency data applied by the vibration exciter and the acceleration data collected by the acceleration sensor according to the time stamp, the frequency data is taken as the horizontal axis, and the acceleration data is taken as the vertical axis, and a frequency response function curve is drawn, and the frequency corresponding to the peak value of the curve is identified as the resonance frequency f of the cultural relic.

[0015] Further, the three-dimensional geological model and the three-dimensional model of the cultural relic are imported into the same analysis environment, the contact relationship (such as binding or friction contact) between the cultural relic and the geological body is set, the boundary conditions (such as base fixed constraint) are defined according to the geological model, the frequency response function curve is converted into a frequency domain excitation, and is applied to the cultural relic model to construct a finite element modal analysis environment for the blasting construction of the cultural relic protection zone.

[0016] Further, in the finite element modal analysis environment for the blasting construction of the cultural relic protection zone, the resonance frequency of the cultural relic is applied, and the acceleration amplitude is gradually increased, each level lasts for 120s. In ANSYS, an elastic-plastic model is used, the residual strain of each node of the cultural relic is calculated through the unloading process, the number of nodes exceeding the residual strain threshold and the average residual strain of the cultural relic at each acceleration amplitude are sorted, and if the number of nodes exceeding the residual strain threshold or the average residual strain exceeds the corresponding threshold, the acceleration amplitude is taken as the tentative damage threshold of the cultural relic. After the simulation of all acceleration amplitudes is completed, the minimum value of the tentative damage threshold of the cultural relic is taken as the ultimate damage threshold A of the cultural relic, and the nodes exceeding the residual strain threshold of the ultimate damage threshold are output as the dangerous nodes of the cultural relic.

[0017] The resonance peak is the area where the energy is concentrated in the sound spectrum, which reflects the physical characteristics of the sound channel. In the frequency response function curve, the resonance peak is the peak value on the curve, which corresponds to the natural frequency of the system, and the structure is easy to be excited at this time.

[0018] Further, the residual strain threshold is 0.005%, the threshold of the number of nodes exceeding the residual strain threshold is 1 / 3 of the number of all nodes of the cultural relic, and the threshold of the average residual strain is also 0.005%.

[0019] Further, the resonance frequency f of the cultural relic and the ultimate damage threshold A of the cultural relic are obtained, and the initial limit value Xz of the blasting vibration safety speed is calculated.

[0020]

[0021] Further, the cultural relic vulnerability influence data such as the service life of the cultural relic, the number of historical repairs, the foundation settlement, the building inclination angle, and the proportion of loose mortise and tenon structure are obtained from the cultural relic historical archives. , and the cultural relic vulnerability evaluation index Cr is calculated.

[0022]

[0023] Wherein, i represents the data number of cultural relic vulnerability influence data, Indicates the weight coefficient corresponding to the cultural relic vulnerability influence data numbered i, i=1, 2, …, n, n is the total number of cultural relic vulnerability influence data.

[0024] Further, the cultural relic vulnerability evaluation index Cr and the initial limit value Xz of the blasting vibration safety speed are obtained, and the corrected limit value Jz of the blasting vibration safety speed is calculated:

[0025]

[0026] Further, according to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, the core area R≤Cr*30m, the buffer area Cr*30m<R≤Cr*60m, and the safety area R>Cr*60m, blasting is strictly prohibited in the core protection area, and a cantilever type tunneling machine or hydraulic splitting method is used for excavation; low-intensity blasting is allowed in the buffer area, the single segment charge is ≤5kg, and a shock absorption joint is formed by pre-splitting blasting; conventional blasting is used in the safety area, but the total charge is controlled, and a hole-by-hole initiation technology is used.

[0027] Further, for the charge of the buffer area and the safety area, the Sadovskiy formula is used as the vibration attenuation model for calculation:

[0028]

[0029] Wherein, Q is the maximum single segment charge, R is the minimum allowable distance from the blasting point to the cultural relic, K and α are site attenuation coefficients.

[0030] (Three) beneficial effects

[0031] The application provides a partitioned blasting construction analysis method for tunnel crossing cultural relic protection areas, which has the following beneficial effects:

[0032] 1. The geological structure point cloud data and the cultural relic body structure point cloud data are collected, the three-dimensional geological model and the cultural relic three-dimensional model are established, the three-dimensional geological model and the cultural relic three-dimensional model are imported into the same analysis environment, the frequency response function curve is converted into a frequency domain excitation, and is applied to the cultural relic model, a finite element modal analysis environment for the blasting construction of the cultural relic protection area is constructed, the natural frequency and the vibration mode of the structure are determined through modal analysis, and a quantitative basis is provided for the dynamic response of the cultural relic under blasting vibration.

[0033] 2. Under the finite element modal analysis environment of blasting construction in the cultural relic protection area, the resonance frequency of the cultural relic is applied to determine the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic, the initial limit value Xz of the blasting vibration safety speed is calculated according to the limit damage threshold A of the cultural relic and the resonance frequency f of the cultural relic, and the blasting vibration safety speed correction limit value Jz is obtained by correcting the initial limit value Xz of the blasting vibration safety speed according to the vulnerability influence data of the cultural relic The blasting vibration safety speed correction limit value Jz is obtained by correcting the initial limit value Xz of the blasting vibration safety speed according to the vulnerability influence data of the cultural relic

[0034] 3. According to the three-level risk area divided according to the cultural relic vulnerability evaluation index Cr, the output of the vibration attenuation model is calculated by using the Sadovsky formula as the vibration attenuation model for the buffer zone and the safe zone, the explosive amount is reasonably distributed, the potential influence on the cultural relic is reduced, the construction vibration is ensured within the safety threshold, and the risk of damage to the cultural relic is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a flowchart of the partition blasting construction analysis method for tunnel crossing the cultural relic protection area. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0037] Please refer to Figure 1 The present application provides a partition blasting construction analysis method for tunnel crossing the cultural relic protection area, comprising the following steps:

[0038] Step one, collect geological structure point cloud data and cultural relic body structure point cloud data, establish three-dimensional geological model and cultural relic three-dimensional model, import three-dimensional geological model and cultural relic three-dimensional model into the same analysis environment, convert frequency response function curve to frequency domain excitation, apply to cultural relic model, and construct finite element modal analysis environment of blasting construction in cultural relic protection area.

[0039] The step one includes the following contents:

[0040] Step 101, collect geological structure point cloud data and cultural relic body structure point cloud data by using geological radar and unmanned aerial vehicle oblique photography, and establish three-dimensional geological model and cultural relic three-dimensional model.

[0041] Step 102, connect the exciter to the non-sensitive part of the cultural relic through a flexible connecting rod (such as the base), and arrange a three-axis acceleration sensor at the key node of the cultural relic (such as the eaves corner and the column base). The electromagnetic exciter applies a linear sweep of 0.1-50Hz with a sweep rate of 1Hz / s and an acceleration amplitude of ≤0.05g. After aligning the frequency data applied by the exciter and the acceleration data collected by the acceleration sensor according to the time stamp, the frequency data is taken as the horizontal axis and the acceleration data is taken as the vertical axis to draw the frequency response function curve. The frequency corresponding to the peak value of the curve is recorded as the resonance frequency f of the cultural relic.

[0042] The resonance peak is the area of energy concentration in the sound spectrum, which reflects the physical characteristics of the sound channel. In the frequency response function curve, the resonance peak appears as a peak on the curve, corresponding to the natural frequency of the system, at which the structure is easily excited.

[0043] Step 103, import the three-dimensional geological model and the three-dimensional model of the cultural relic into the same analysis environment, set the contact relationship between the cultural relic and the geological body (such as binding or friction contact), define the boundary conditions according to the geological model (such as base fixed constraint), convert the frequency response function curve to frequency domain excitation, and apply it to the cultural relic model to build a finite element modal analysis environment for blasting construction in the cultural relic protection area.

[0044] In use, the contents in steps 101 to 103 are combined:

[0045] Collect the point cloud data of the geological structure and the point cloud data of the cultural relic body, establish a three-dimensional geological model and a three-dimensional model of the cultural relic, import the three-dimensional geological model and the three-dimensional model of the cultural relic into the same analysis environment, convert the frequency response function curve to frequency domain excitation, apply it to the cultural relic model, and build a finite element modal analysis environment for blasting construction in the cultural relic protection area. Determine the natural frequency and mode shape of the structure through modal analysis to provide quantitative basis for the dynamic response of the cultural relic under blasting vibration.

[0046] Step two, in the finite element modal analysis environment for blasting construction in the cultural relic protection area, apply the resonance frequency of the cultural relic to determine the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic. According to the limit damage threshold A of the cultural relic and the resonance frequency f of the cultural relic, calculate the initial limit value Xz of the blasting vibration safety speed, and according to the vulnerability influence data of the cultural relic Calculate the vulnerability evaluation index Cr of the cultural relic, and correct the initial limit value Xz of the blasting vibration safety speed to obtain the corrected limit value Jz of the blasting vibration safety speed.

[0047] The step two includes the following contents:

[0048] Step 201, under the finite element modal analysis environment of blasting construction in the cultural relic protection area, the resonance frequency of the cultural relic is applied, the acceleration amplitude is gradually increased (0.1g→0.2g→0.3g…), each level lasts for 120s, the elastic-plastic model is used in ANSYS, the residual strain of each node of the cultural relic is calculated through the unloading process, the number of nodes exceeding the residual strain threshold and the average residual strain of the cultural relic under each acceleration amplitude are sorted, if the number of nodes exceeding the residual strain threshold or the average residual strain exceeds the corresponding threshold, the acceleration amplitude is recorded as the tentative damage threshold of the cultural relic, after the simulation of all acceleration amplitudes is completed, the minimum value of the tentative damage threshold of the cultural relic is taken as the limit damage threshold A of the cultural relic, and the nodes exceeding the limit damage threshold are output as the dangerous nodes of the cultural relic.

[0049] Wherein, the residual strain threshold is 0.005%, the threshold of the number of nodes exceeding the residual strain threshold is 1 / 3 of the number of all nodes of the cultural relic, and the threshold of the average residual strain is also 0.005%.

[0050] Step 202, the limit damage threshold A of the cultural relic and the resonance frequency f of the cultural relic are obtained, and the initial limit value Xz of the blasting vibration safety speed is calculated:

[0051]

[0052] Step 203, the cultural relic vulnerability influence data such as the service life, the historical repair times, the foundation settlement, the building inclination angle and the proportion of loose mortise structure of the cultural relic are obtained from the historical archives of the cultural relic , the cultural relic vulnerability evaluation index Cr is calculated:

[0053]

[0054] Wherein, i represents the data number of the cultural relic vulnerability influence data, represents the weight coefficient corresponding to the cultural relic vulnerability influence data numbered i, i=1, 2, …, n, and n is the total number of cultural relic vulnerability influence data.

[0055] Step 204, the cultural relic vulnerability evaluation index Cr and the initial limit value Xz of the blasting vibration safety speed are obtained, and the corrected limit value Jz of the blasting vibration safety speed is calculated:

[0056]

[0057] When used, the contents in steps 201 to 204 are combined:

[0058] Under the finite element modal analysis environment of blasting construction in the cultural relic protection area, the cultural relic resonance frequency is applied, the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic are determined, the initial limit value Xz of the blasting vibration safety speed is calculated according to the limit damage threshold A of the cultural relic and the cultural relic resonance frequency f, and the blasting vibration safety speed correction limit value Jz is obtained by correcting the initial limit value Xz of the blasting vibration safety speed according to the cultural relic vulnerability influence data The blasting vibration safety speed correction limit value Jz is obtained by correcting the initial limit value Xz of the blasting vibration safety speed according to the cultural relic vulnerability influence data, the accurate correction of the safety threshold is realized by quantifying the cultural relic vulnerability and the vibration response, the all-around optimization of the blasting construction is provided, and the triple promotion of safety, efficiency and cost is achieved.

[0059] Step three, according to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, and for the buffer zone and the safety zone, the Sadovski formula is used as a vibration attenuation model to calculate the output.

[0060] The step three includes the following contents:

[0061] Step 301, according to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, the core area (R<=Cr*30m), the buffer area (Cr*30m

[0062] Step 302, for the buffer zone and the safety zone, the Sadovski formula is used as a vibration attenuation model to calculate:

[0063]

[0064] Wherein, Q is the maximum single segment charge, R is the minimum allowable distance from the blasting point to the cultural relic, K and alpha are site attenuation coefficients, and are calibrated through field test.

[0065] In use, the contents in steps 301 and 302 are combined:

[0066] According to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, and for the buffer zone and the safety zone, the Sadovski formula is used as a vibration attenuation model to calculate the output, the charge is reasonably distributed, the potential influence on the cultural relic is reduced, the construction vibration is ensured to be within the safety threshold, and the risk of damage to the cultural relic is reduced.

[0067] The present application provides another embodiment of a method for quantifying cultural relic vulnerability influence data:

[0068] Age (A1) is classified by age: Ming and Qing (300-600 years) 1 point, Song and Yuan (600-1000 years) 2 points, Tang and before (>1000 years) 3 points

[0069] Historical repair times (A2) increase by 1 repair, score +0.5 points (upper limit 3 points)

[0070] Foundation settlement (A3) differential settlement rate (mm / year) ≤0.5, 0 points, 0.5-1.0, 1 point, >1.0, 2 points

[0071] Building tilt angle (A4) tilt rate (‰) ≤1.0, 0 points, 1.0-3.0, 1 point, >3.0, 2 points

[0072] Loose proportion of mortise and tenon (A5) Loose node ratio ≤10%, 0 points, 10-30%, 1 point, >30%, 2 points

[0073] The present application provides another embodiment of the method for allocating index weight of cultural relic vulnerability influence data:

[0074] The weight is determined by using the analytic hierarchy process (AHP), the judgment matrix is constructed by expert scoring, and the consistency ratio (CR<0.1) is calculated:

[0075] Index Age (A1) Repair times (A2) Settlement (A3) Tilt angle (A4) Mortise and tenon loosening (A5) Weight (w)

[0076] A1 1 1 / 2 2 3 4 0.32

[0077] A2 2 1 3 4 5 0.42

[0078] A3 1 / 2 1 / 3 1 2 3 0.15

[0079] A4 1 / 3 1 / 4 1 / 2 1 2 0.08

[0080] A5 1 / 4 1 / 5 1 / 3 1 / 2 1 0.03

[0081] The present application provides another embodiment of the method for calculating the index of cultural relics:

[0082] The evaluation data of a Qing Dynasty wooden tower: age: 200 years (1 point), repair times: 3 times (1.5 points), settlement: 0.8 mm / year (1 point), tilt angle: 2.5‰ (1 point), mortise and tenon loosening: 15% (1 point):

[0083] Calculation process:

[0084] = 0.32 x 1 + 0.42 x 1.5 + 0.15 x 1 + 0.08 x 1 + 0.03 x 1 = 1.18

[0085] The above-described embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, the above-described embodiments can be implemented in the form of a computer program product. A person of ordinary skill in the art can be aware that the units and algorithm steps of the examples described in connection with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solutions.

[0086] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., they can be located in one place or distributed on multiple network units. Part or all of the units can be selected to achieve the purpose of the embodiments according to actual needs.

[0087] The above is merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered by the protection scope of the present application.

Claims

1. A method for analyzing the construction of a partitioned blasting for tunneling through a cultural heritage protection zone, characterized in that: Comprising the following steps: Collecting geological structure point cloud data and cultural relic body structure point cloud data, establishing a three-dimensional geological model and a three-dimensional cultural relic model, importing the three-dimensional geological model and the three-dimensional cultural relic model into the same analysis environment, converting the frequency response function curve into a frequency domain excitation, applying it to the cultural relic model, and constructing a finite element modal analysis environment for blasting construction in the cultural relic protection zone; Under the finite element modal analysis environment of blasting construction in the cultural relic protection area, the resonance frequency of the cultural relic is applied to determine the limit damage threshold A of the cultural relic and the dangerous node of the cultural relic. According to the limit damage threshold A of the cultural relic and the resonance frequency f of the cultural relic, the initial limit value Xz of the blasting vibration safety speed is calculated, and according to the vulnerability influence data of the cultural relic The vulnerability evaluation index Cr of the cultural relic is calculated, and the initial limit value Xz of the blasting vibration safety speed is corrected to obtain the corrected limit value Jz of the blasting vibration safety speed. Under the finite element modal analysis environment for blasting construction in the cultural relic protection zone, the cultural relic resonance frequency is applied, the acceleration amplitude is gradually increased, each level lasts for 120s, the elastic-plastic model is used in ANSYS, the residual strain of each node of the cultural relic is calculated through the unloading process, the number of nodes exceeding the residual strain threshold and the average residual strain of the cultural relic at each acceleration amplitude are sorted out, if the number of nodes exceeding the residual strain threshold or the average residual strain exceeds the corresponding threshold, the acceleration amplitude is recorded as the tentative damage threshold of the cultural relic, after the simulation of all acceleration amplitudes is completed, the minimum value of the tentative damage threshold of the cultural relic is taken as the ultimate damage threshold A of the cultural relic, and the nodes exceeding the residual strain threshold of the ultimate damage threshold are output as the dangerous nodes of the cultural relic; Obtaining the relic vulnerability influence data of relic age, historical repair times, foundation settlement amount, building inclination angle and proportion of loose mortise and tenon structure from historical archives of relics , calculating the relic vulnerability evaluation index Cr: Wherein, i represents the data number of cultural relic vulnerability influence data, The weight coefficient corresponding to the cultural relic vulnerability influence data numbered i, i=1, 2, …, n, n is the total number of cultural relic vulnerability influence data. According to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, and for the buffer zone and the safety zone, the Sadaovsky formula is used as the vibration attenuation model for calculation and output; According to the cultural relic vulnerability evaluation index Cr, three risk zones are divided, the core zone R≤Cr*30m, the buffer zone Cr*30m<R≤Cr*60m, and the safety zone R>Cr*60m, blasting is strictly prohibited in the core protection zone, and cantilever tunneling machines or hydraulic splitting methods are used for excavation; low-intensity blasting is allowed in the buffer zone, the single segment explosive charge is ≤5kg, and a shock absorption joint is formed by pre-splitting blasting; conventional blasting is used in the safety zone, but the total explosive charge is controlled, and the hole-by-hole initiation technique is adopted. Wherein, R is the minimum allowable distance from the blasting point to the cultural relic.

2. The zoning blasting construction analysis method for tunneling through a cultural relic protection zone according to claim 1, characterized in that: The exciter is connected to the non-sensitive part of the cultural relic through a flexible connecting rod, and a three-axis acceleration sensor is arranged at a key node of the cultural relic, an electromagnetic exciter applies a linear sweep of 0.1-50Hz at a sweep rate of 1Hz / s, and the acceleration amplitude is ≤0.05g, after the frequency data applied by the exciter and the acceleration data collected by the acceleration sensor are aligned according to the time stamp, the frequency data is taken as the horizontal axis and the acceleration data is taken as the vertical axis, a frequency response function curve is drawn, the frequency corresponding to the peak value of the curve is identified, and is recorded as the cultural relic resonance frequency f.

3. The zoning blasting construction analysis method for tunneling through a cultural relic protection zone according to claim 1, characterized in that: wherein The residual strain threshold is 0.005%, the threshold for the number of nodes exceeding the residual strain threshold is 1 / 3 of the total number of nodes of the cultural relic, and the threshold for the average residual strain is also 0.005%.

4. The zoning blasting construction analysis method for tunneling through a cultural relic protection zone according to claim 1, characterized in that: The cultural relic ultimate damage threshold A and the cultural relic resonance frequency f are obtained, and the initial limit value Xz of the blasting vibration safety speed is calculated: 。 5. The method according to claim 1, wherein the method comprises the following steps: Obtaining the vulnerability evaluation index Cr of cultural relics and the initial limit value Xz of the blasting vibration safety speed, and calculating the corrected limit value Jz of the blasting vibration safety speed: 。 6. The method according to claim 1, wherein the method comprises the following steps: For the explosive quantity of the buffer zone and the safety zone, the Sadaovsky formula is used as the vibration attenuation model for calculation: Wherein, Q is the maximum explosive quantity of a single section, R is the minimum allowable distance from the blasting point to the cultural relics, and K and a are the site attenuation coefficients.

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