CN115542393A - Full-waveform inversion method of roadway while digging based on multi-parameter constraints and structure correction - Google Patents

Abstract

The invention discloses a full-waveform inversion method based on multi-parameter constraints and structure correction, which includes the following steps: Step 1, constructing an initial full-waveform inversion model, and then adopting a multi-scale elastic wave full-waveform inversion method to Perform single-scale inversion of the initial model; step 2, perform multi-parameter weighted constraint structure correction on the single-scale inversion results, and obtain preliminary correction results; step 3, perform one-dimensional wave velocity profile on the preliminary correction results based on pre-set constraints Spatial structure correction and smoothing constraints to obtain the secondary correction result; step 4, use the secondary correction result as the initial model of the next scale, and continue the full waveform inversion; repeat steps 2 to 4 until all scale inversions are completed, Get the full waveform inversion result. The present invention can effectively solve the problems that the observation system is highly restrictive, the amount of detection data is small, the offset distance is relatively small, and the waveform inversion has multiple solutions in the advanced detection of the roadway with excavation, and the inversion effect is improved.

Description

Full-waveform inversion method of roadway while digging based on multi-parameter constraints and structure correction

technical field

The present invention relates to the field of mine exploration and imaging technology, in particular to a method for full waveform inversion of roadway with excavation based on multi-parameter constraints and structural correction, and more specifically to a method based on multi-parameter weighted constraints and wave velocity profile spatial structure correction. Full waveform inversion method of elastic wave detection in roadway while excavating.

Background technique

As one of the two core links of coal mine production, the demand for intelligent development of tunneling is extremely urgent. However, during the tunneling process, coal and gas outbursts, water inrush and other disasters seriously threaten the safety of tunneling production and the personal safety of miners. Geological assurance technology is the basis for the safety assurance of intelligent coal production, the basic data source to realize geological prediction, disturbance perception and risk assessment before, during and after roadway excavation construction, and the prerequisite guarantee for the implementation of all key technologies of intelligent excavation.

However, at present, the imaging interpretation results of advanced seismic detection in mines are mostly "drawing arcs", there are many false anomaly interfaces, and the imaging accuracy is low (as shown in Figure 1), which is difficult to meet the geological guarantee requirements of roadway intelligent excavation.

The full waveform inversion method can make full use of the kinematics and dynamics characteristics of seismic waves to obtain subsurface model parameter information. It has the advantages of high imaging precision of complex structures and good inversion effect of physical parameters, and has been well applied in surface seismic exploration. As a result, it is the best choice for advanced seismic detection and imaging in mines in the future, and can meet the geological security requirements of intelligent tunneling. However, the seismic advanced detection mode is different from the surface detection, and its observation system is more restrictive. Only a series of linearly arranged shot points and receiver points are arranged on the center line behind the excavation head. Range-shift detection, and limited by the detection space, the number of deployed shot points and receiver points is limited. Therefore, this detection mode has a small amount of data and a small offset distance, which will increase the multi-solution of the full waveform inversion, and the physical properties Parameter calculation errors increase.

Therefore, how to provide a high-precision full-waveform inversion method suitable for mine tunnel detection mode is an urgent problem to be solved by those skilled in the art.

Contents of the invention

In view of this, the present invention provides a full-waveform inversion method based on multi-parameter constraints and structure correction, combined with multi-parameter weighted constraints and wave velocity profile spatial structure correction, effectively solves the problem of the limited observation system in roadway advanced detection. Strong, small amount of detection data and small offset, and strong multi-solution of waveform inversion, improve the inversion effect, and realize high-precision imaging of abnormal geological structures ahead of excavation.

In order to achieve the above object, the present invention adopts the following technical solutions:

A full-waveform inversion method for tunnels with excavation based on multi-parameter constraints and structural correction, including the following steps:

Step 1. Input the theoretical simulation data or the actual measured conventional roadway seismic advance data, construct the initial model of full waveform inversion, and then use the multi-scale elastic wave full waveform inversion method to perform single-scale inversion of the initial model;

Step 2. Perform multi-parameter weighted constraint structure correction on the single-scale inversion results obtained in step 1 to obtain preliminary correction results;

Step 3. Based on the pre-set restriction conditions, the one-dimensional wave velocity profile spatial structure correction and smoothing constraints are performed on the preliminary correction results to obtain the secondary correction results;

Step 4. Use the secondary correction result obtained in step 3 as the initial model of the next scale, and continue to perform full waveform inversion according to the method of step 1;

Step 5. Steps 2 to 4 are repeated until the inversion of all scales is completed, and the full waveform inversion result of the roadway advanced detection elastic wave is obtained.

Further, in step 2, the multi-parameter weighted constraint structure correction is performed according to the following formula:

Among them, Δm is the model update amount of a single iteration; Δm′ is the model update amount after multi-parameter weighted structure correction; m is the initial model; i, j represent the positions of grid nodes in the z and x directions respectively; m _{i, j} ^p where P-wave velocity, shear-wave velocity or density is a single parameter initial model i, j grid node position parameter value; nz is the number of vertical grid points in the model, nx is the number of horizontal grid points in the model; V _p is the longitudinal wave velocity; V _s is the shear wave Speed; Den is density.

Further, in step 3, the preset restriction conditions are:

进行压制，变为0；Set the limit condition 1 according to the actual needs. The limit condition 1 is based on the value value of the lower limit of space correction, and the update amount of the model that is lower than the value value of the lower limit of space correction

Suppress and become 0;

Set the second restriction condition according to the actual needs. The second restriction condition is based on the scope of the structure correction area and the distance between the areas. There is an update amount on both sides of the positive value area and the negative value area, when the range of the area and the distance between the areas meet the second constraint condition, the positive value area that exists on both sides of the negative value area or the positive value area that exists on both sides of the positive value area The model update amount in the negative value area is suppressed and becomes 1/5 of the original model update value.

Further, step 3 includes:

其中，x为横轴坐标；Step 301, select a grid coordinate y _i on the vertical axis, and extract a one-dimensional wave velocity profile along the axis of the roadway

Among them, x is the horizontal axis coordinate;

对应的模型更新量

与斜率

Step 302, calculate the one-dimensional wave velocity profile

Corresponding model update amount

with slope

进行压制，变为0，得到校正后的模型更新量

Step 303, update the model value lower than the lower limit value of space correction

Suppress and change to 0 to get the corrected model update amount

按照限制条件二对一维波速剖面上的每个网格点进行逐一判定和校正，得到校正后的模型更新量

Step 304, according to the corrected model update amount

According to the second constraint condition, each grid point on the one-dimensional wave velocity profile is judged and corrected one by one, and the corrected model update amount is obtained

与斜率

按照斜率符号变化情况对一维波速剖面上的每个网格点进行逐一判定，得到校正后的模型更新量

Step 305, according to the corrected model update amount

with slope

According to the change of the slope sign, each grid point on the one-dimensional wave velocity profile is judged one by one, and the corrected model update amount is obtained

计算校正后的一维波速剖面

Step 306, according to the corrected model update amount

Calculate the corrected 1D wave velocity profile

Step 307, take the next vertical axis grid coordinate y _i+1 , repeat steps 302 to 306, until the correction of the one-dimensional wave velocity profile of all grids is completed, and the quadratic Calibration result.

Further, step 305 includes:

When there are two points where the model update amount is zero between the three adjacent points where the sign of the slope changes, the sign of the model update amount of the grid points before and after the two points changes, and there is no slope between the two points is 0 , then correct the model update amount of the grid points in the area between the three adjacent points where the slope sign changes, and become a two-point model of the first slope sign change point and the third slope sign change point The average value of the update amount to get the corrected model update amount

继续校正，当斜率符号发生变化的不相邻的两个点之间范围内所有网格点模型更新量符号未发生改变，则对两个斜率符号变化点之间区域内的网格点的模型更新量进行校正，变为区域内所有网格点模型更新量的平均值，得到校正后的模型更新量

Then according to the corrected model update amount

Continue to correct, when the sign of all grid point model updates in the range between two non-adjacent points where the slope sign changes does not change, then the model of the grid point in the area between the two slope sign change points The update amount is corrected to become the average update amount of all grid point models in the area, and the corrected model update amount is obtained

Further, the inversion results in step 5 include: longitudinal wave inversion results, shear wave inversion results and density inversion results.

It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a full waveform inversion method based on multi-parameter constraints and structural correction, which has the following beneficial effects:

(1) The present invention adopts the elastic wave full waveform inversion method, which utilizes the longitudinal wave velocity, shear wave velocity and density parameters in the observation records, and can obtain more accurate underground medium information than the acoustic wave full waveform inversion.

(2) The present invention performs two corrections by performing multi-parameter weighted constraint structure correction and one-dimensional wave velocity profile space structure correction and smoothing constraints on the inversion results at a single scale, and realizes high-precision abnormal geological structures in front of roadway excavation Imaging, imaging results can accurately determine the location and occurrence of geological anomalies, and fill the gap in full waveform inversion technology in the field of advanced mine detection.

(3) The inversion strategy of the present invention not only provides a higher-precision initial model for the next scale inversion, but also avoids the problem of excessive aggravation of false anomalies in multiple iterations. After the false anomalies are eliminated by structural correction, the full waveform is constrained direction of inversion.

(4) The present invention basically solves the problems of small amount of detection data, relatively small offset distance, and strong multi-solution of waveform inversion in the advance detection of roadway, improves the inversion effect, and improves the accuracy of full waveform inversion by about 20%.

(5) While the present invention improves the inversion precision, it does not increase the calculation amount of the full waveform inversion.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is conventional mine seismic advance detection imaging result provided by the present invention;

Fig. 2 is the flow chart of the full waveform inversion method for elastic wave detection with digging roadway provided by the present invention;

Fig. 3 is a schematic diagram of the one-dimensional wave velocity profile model update amount and slope change determination provided by the present invention;

Fig. 4 is the structural representation of the initial model provided by the present invention;

Fig. 5 is the complex advanced geological theoretical model provided by the present invention;

Fig. 6 adopts the inversion result obtained by the method of the present invention provided by the present invention;

Fig. 7 is the full waveform inversion result of multi-scale elastic wave in conventional time domain provided by the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figure 2, the embodiment of the present invention discloses a method for full waveform inversion of tunnels with excavation based on multi-parameter constraints and structural correction, including the following steps:

Step 1. Input the theoretical simulation data or the actual measured conventional roadway seismic advance detection data, construct the initial model of full waveform inversion (as shown in Figure 4), and then use the multi-scale elastic wave full waveform inversion method to perform single-scale inversion of the initial model ; The inversion includes three sets of parameters, namely the P-wave velocity model, the S-wave velocity model and the density model.

Step 2. Perform multi-parameter weighted constraint structure correction on the single-scale inversion results obtained in step 1 to obtain preliminary correction results;

Step 3. Based on the pre-set restriction conditions, the one-dimensional wave velocity profile spatial structure correction and smoothing constraints are performed on the preliminary correction results to obtain the secondary correction results;

Step 4. Use the secondary correction result obtained in step 3 as the initial model of the next scale, and continue to perform full waveform inversion according to the method of step 1;

Step 5. Steps 2 to 4 are repeated until the inversion of all scales is completed, and the full waveform inversion result of the roadway advanced detection elastic wave is obtained. Inversion results include: longitudinal wave inversion results, shear wave inversion results and density inversion results.

In the present invention, the seismic source is distributed in the middle of the coal seam, multiple horizontal component and vertical component geophones are arranged linearly with the seismic source, and are also distributed in the middle of the coal seam to receive seismic signals, and the inversion initial model is set according to the medium condition of the uniform layered coal measure strata.

Due to the special observation system conditions of the advance detection of the roadway, the multi-solution problem of the conventional time-domain multi-scale elastic wave full waveform inversion method is enhanced, and it is difficult to further improve the inversion accuracy from the perspective of data. Starting from the model structure, the present invention discovers the special structural features implied in the geological anomaly in the results of full-waveform inversion in advance detection of tunnels, and constructs correction items according to the structural features, constrains the direction of full-waveform inversion, and obtains a structure that meets the preset structural features The inversion result improves the inversion effect.

The special structural features implied by the geological anomalies in the full waveform inversion results of the advanced detection of the tunnel discovered in the elastic wave are as follows:

(1) For the recovery of abnormal geological structures, the inversion effect of density parameters is the best, while the effect of suppressing false anomalies and disturbance interference in P- and S-wave parameters is better;

(2) Although the longitudinal, shear and density have large differences in physical parameters, they have the same geological structure characteristics;

(3) There are false anomalous areas near the boundaries on both sides of the abnormal geological structure that are opposite to their own attributes;

(4) There is a "W" or "M" type anomaly in the lateral velocity-depth curve of the grid points in the vertical direction, and the model update sign of the middle range of the "W" or "M" area is opposite to that of the model update sign of the range on both sides;

(5) The lateral velocity-depth curves of grid points in the vertical direction in the larger structure have the characteristics of "wavy lines", and the model update symbols within the range involved by the "wavy lines" are consistent.

Based on the above-mentioned features found, the present invention introduces multi-parameter weighting constraints and one-dimensional wave velocity profile spatial structure correction to correct the inversion results multiple times, which can effectively solve the problem of less detection data and small offsets in roadway advanced detection. Waveform inversion is a multi-solution problem, which improves the inversion effect and realizes high-precision imaging of abnormal geological structures ahead of excavation.

Next, the correction methods of steps 2 and 3 will be described in detail.

In a specific embodiment, in step 2, the multi-parameter weighted constraint structure correction is performed according to the following formula:

Among them, Δm is the update amount of the single iteration model (that is, the change amount between the current iteration model and the last iteration model); Δm′ is the model update amount after multi-parameter weighted structure correction; m is the initial model; i, j respectively Indicates the position of the grid node in the z, x direction; m _{i, j} ^p is the parameter value of the initial model i, j grid node position of the single parameter of P-wave velocity, shear wave velocity or density; nz is the number of vertical grid points of the model, and nx is The number of transverse grid points in the model; V _p is the velocity of P-wave; V _s is the velocity of S-wave; Den is the density

In a specific embodiment, in step 3, the preset restriction conditions are:

进行压制，变为0；实际应用时，根据数据处理效果进行自主设定，一般通过正式反演前的实验确定。例如，将该值设定为小于初始模型参数的5％。Restriction condition 1, restriction condition 1 is based on the value value of the lower limit of space correction, and the update amount of the model that is lower than the value value of the lower limit of space correction

It is suppressed and becomes 0; in actual application, it is set independently according to the data processing effect, and is generally determined through experiments before the formal inversion. For example, set this value to less than 5% of the initial model parameters.

Restriction condition 2. Restriction condition 2 is based on the scope of the structural correction area and the distance between areas. When the model update amount is negative, there is a positive update area on both sides of the area, or when the model update amount is a positive area. There is an area with a negative update value on both sides. When the range of the area and the distance between the areas meet the second constraint condition, the positive area on both sides of the negative area or the negative area on both sides of the positive area The model update amount of the model is suppressed and becomes 1/5 of the original model update value.

Among them, the "distance between areas" refers to: when "there is an area with a positive update amount on both sides of the negative area", the distance between the "positive area" on one side and the "negative area" in the middle; or: When "there is an area with negative update amount on both sides of the area with positive update amount", the distance from the "negative area" on one side to the "positive area" in the middle.

"Area range" refers to: when "there is an area with a positive update amount on both sides of the negative value area", the range size of the "positive value area" on one side, or: "the update amount is positive on both sides of the area." When the update amount is a negative value area", the range size of the "negative value area" on one side.

The range of regions and the distance between regions are generally determined through experiments before formal inversion. For example: "Area range: "There is an area with a positive update amount on both sides of the negative area", the size of the "positive area" on one side cannot be less than 1/2 of the range of the middle "positive area".

"Distance between areas": When "there is a positive area with an update amount on both sides of the negative area", the distance between the "positive area" on one side and the "negative area" in the middle cannot be greater than the "negative area" in the middle the size of.

Specifically, step 3 includes:

其中，x为横轴坐标；Step 301, select a grid coordinate y _i on the vertical axis, and extract a one-dimensional wave velocity profile along the axis of the roadway

Among them, x is the horizontal axis coordinate;

对应的模型更新量

与斜率

Step 302, calculate the one-dimensional wave velocity profile

Corresponding model update amount

with slope

为第e次迭代时的一维波速剖面，

为第e-1次迭代时的一维波速剖面。Among them, the amount of model update:

is the one-dimensional wave velocity profile at the e-th iteration,

is the one-dimensional wave velocity profile at the e-1th iteration.

为一维波速剖面

横向第j个网格点的数值，

为一维波速剖面

横向第j-1个网格点的数值，dx为模型横向网格间距。Slope:

is a one-dimensional wave velocity profile

The value of the jth grid point in the horizontal direction,

is a one-dimensional wave velocity profile

The value of the j-1th grid point in the horizontal direction, dx is the horizontal grid spacing of the model.

进行压制，变为0，得到校正后的模型更新量

Step 303, update the model value lower than the lower limit value of space correction

Suppress and change to 0 to get the corrected model update amount

按照限制条件二对一维波速剖面上的每个网格点进行逐一判定和校正，得到校正后的模型更新量

Step 304, according to the corrected model update amount

According to the second constraint condition, each grid point on the one-dimensional wave velocity profile is judged and corrected one by one, and the corrected model update amount is obtained

与斜率

按照斜率符号变化情况对一维波速剖面上的每个网格点进行逐一判定，得到校正后的模型更新量

Step 305, according to the corrected model update amount

with slope

According to the change of the slope sign, each grid point on the one-dimensional wave velocity profile is judged one by one, and the corrected model update amount is obtained

When there are two points where the model update amount is zero between the three adjacent points where the sign of the slope changes (as shown in Figure 3), the sign of the model update amount of the grid points before and after the two points changes, and the two points If there is no point with a slope of 0 between the points, the model update amount of the grid points in the area between the three adjacent points where the slope sign changes is corrected, so that the first slope sign change point and the third The average value of the two-point model update amount at the point where the slope sign changes, and the corrected model update amount is obtained

继续校正，当斜率符号发生变化的不相邻的两个点之间范围内所有网格点模型更新量符号未发生改变，则对两个斜率符号变化点之间区域内的网格点的模型更新量进行校正，变为区域内所有网格点模型更新量的平均值，得到校正后的模型更新量

Then according to the corrected model update amount

Continue to correct, when the sign of all grid point model updates in the range between two non-adjacent points where the slope sign changes does not change, then the model of the grid point in the area between the two slope sign change points The update amount is corrected to become the average update amount of all grid point models in the area, and the corrected model update amount is obtained

In order to control the correction range, it is necessary to search and judge according to the set area limit. That is to say, the maximum correction range is controlled, for example, if it is set to 10 grid points, "searching and judging according to the set area limit value" means to search sequentially according to 10 grid points as a round.

计算校正后的一维波速剖面

Step 306, according to the corrected model update amount

Calculate the corrected 1D wave velocity profile

Step 307, take the next vertical axis grid coordinate y _i+1 , repeat steps 302 to 306, until the correction of the one-dimensional wave velocity profile of all grids is completed, and the quadratic Calibration result.

In order to further verify the effectiveness and high efficiency of the present invention based on the multi-parameter weighting constraints and wave velocity profile spatial structure correction method for elastic wave full waveform inversion of roadway detection while digging, the scheme proposed by the present invention is used in the complex advanced geological theoretical model ( Figure 5), the obtained inversion results are shown in Figure 6.

The conventional time-domain multi-scale full-waveform inversion results of elastic waves (as shown in Figure 7) will be used as the comparative research object. Comparing Figures 6 and 7, it can be seen that the full-waveform inversion results obtained by the present invention are closer to the real model. In the inversion results, the boundaries on both sides of the subsidence column and the fault fracture zone are clear, and the internal parameters of the structure are well restored, and the lithological interfaces of small-scale faults are also restored and displayed; the most obvious is that the false anomalies and disturbances in the results are basically suppressed Completely, the inversion accuracy has been greatly improved. Comparing the numerical difference between the inversion result and the real model, the accuracy of the full waveform inversion is improved by about 20%.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the related information, please refer to the description of the method part.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (6)

1. A roadway driving full-waveform inversion method based on multi-parameter constraint and structural correction is characterized by comprising the following steps:

step 1, inputting theoretical simulation data or actual measurement conventional roadway seismic advanced detection data, constructing a full-waveform inversion initial model, and performing single-scale inversion on the initial model by adopting a multi-scale elastic wave full-waveform inversion method;

step 2, carrying out multi-parameter weighted constraint structure correction on the single-scale inversion result obtained in the step 1 to obtain a primary correction result;

step 3, based on preset limiting conditions, carrying out one-dimensional wave velocity profile space structure correction and smooth constraint on the primary correction result to obtain a secondary correction result;

step 4, taking the secondary correction result obtained in the step 3 as an initial model of the next scale, and continuing to perform full waveform inversion according to the mode of the step 1;

and 5, repeatedly executing the step 2 to the step 4 until all scales are inverted, and obtaining a full waveform inversion result of the roadway advanced detection elastic wave.

2. The method as claimed in claim 1, wherein in step 2, the multiparameter weighted constraint structure correction is performed according to the following formula:

wherein, Δ m is the updating amount of the single iteration model; Δ m' is the model update amount after the multi-parameter weighting structure correction; m is an initial model; i and j respectively represent the positions of the grid nodes in the z and x directions; m is a unit of _i,j ^p Parameter values of the positions of nodes of an i, j grid of a single parameter initial model of longitudinal wave velocity, transverse wave velocity or density are obtained; nz is the number of model vertical grid points, nx is the number of model horizontal grid points; v _p Is the velocity of the longitudinal wave; v _s Is the transverse wave velocity; den is the density.

3. The method for performing full waveform inversion along with the roadway based on multi-parameter constraint and structural correction as recited in claim 1, wherein in step 3, the preset limiting conditions are as follows:

setting a first limiting condition according to actual needs, wherein the first limiting condition takes the spatial correction lower limit value as a judgment basis, and the model update amount lower than the spatial correction lower limit value is set

Pressing to become 0;

and setting a second limiting condition according to actual needs, wherein the second limiting condition takes the range of the structural correction area and the distance between the areas as a judgment basis, when the model updating amount is a negative value area, both sides of the area have an updating amount which is a positive value area, or when the model updating amount is a positive value area, both sides of the area have an updating amount which is a negative value area, and when the area range and the distance between the areas meet the second limiting condition, the model updating amount in the positive value area existing on both sides of the negative value area or the negative value area existing on both sides of the positive value area is suppressed to be 1/5 of the original model updating value.

4. The method for full waveform inversion along with the roadway based on multi-parameter constraint and structure correction as recited in claim 2, wherein the step 3 comprises:

301, selecting a grid coordinate y of a longitudinal axis _i Extracting one-dimensional wave velocity profile along the axis of the tunnel

Wherein x is a horizontal axis coordinate;

step 302, calculate a one-dimensional wave velocity profile

Corresponding model update amount

And slope

Step 303, updating the model below the value of the lower value of the spatial correction limit

Pressing to 0 to obtain corrected model update amount

Step 304, updating the quantity according to the corrected model

Judging and correcting each grid point on the two-dimensional wave velocity profile one by one according to the limiting conditions to obtain the corrected model updating amount

Step 305, updating quantity according to corrected model

And slope of

Judging each grid point on the one-dimensional wave velocity profile one by one according to the change condition of the slope symbol to obtain the corrected model updating amount

Step 306, updating the quantity according to the corrected model

Calculating the corrected one-dimensional wave velocity profile

Step 307, take down a grid coordinate y of the vertical axis _i+1 And repeating the step 302 to the step 306 until the correction of all the grid one-dimensional wave velocity profiles is completed, and obtaining a secondary correction result after the spatial structure correction and the smoothing constraint of the one-dimensional wave velocity profiles.

5. The method of claim 4, wherein the step 305 comprises:

when two points with zero model updating quantity exist between three adjacent points with changed slope symbols, the symbols of the model updating quantity of grid points before and after the two points occurAnd if the two points are not provided with the point with the slope of 0, correcting the model updating amount of the grid point in the area between the three adjacent points with the changed slope sign to obtain the average value of the model updating amounts of the two points of the first slope sign change point and the third slope sign change point, and obtaining the corrected model updating amount

Then according to the updated quantity of the corrected model

Continuing to correct, when the signs of the model updating quantities of all the grid points in the range between two nonadjacent points with changed slope signs are not changed, correcting the model updating quantities of the grid points in the region between the two slope sign change points, changing the model updating quantities into the average value of the model updating quantities of all the grid points in the region, and obtaining the corrected model updating quantities

6. The method for performing full waveform inversion along with the roadway based on multi-parameter constraint and structural correction as claimed in claim 1, wherein the inversion result in step 5 comprises: longitudinal wave inversion results, shear wave inversion results and density inversion results.

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