CN109766628B

CN109766628B - Three-level cyclic progressive quantification method for sudden surge hidden danger degree of large buried depth tunnel

Info

Publication number: CN109766628B
Application number: CN201910015226.1A
Authority: CN
Inventors: 黄世武
Original assignee: GUANGXI XINDA HIGHWAY CO Ltd
Current assignee: GUANGXI XINDA HIGHWAY CO Ltd
Priority date: 2019-01-08
Filing date: 2019-01-08
Publication date: 2020-03-24
Anticipated expiration: 2039-01-08
Also published as: CN109766628A

Abstract

A three-level cyclic progressive quantification method for the inrush hidden danger degree of a large buried depth tunnel; when the buried depth h of the tunnel_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called as a large buried depth tunnel; big (a)The first-level quantification of the hidden inrush danger degree of the buried tunnel is to determine the inrush source form coefficient J of the geological block_{Deep to}(ii) a The second level of quantization is to quantize J_{Deep to}The construction disturbance factor of the large buried depth tunnel section is integrated to obtain the inrush intensity G of the equivalent section of the large buried depth tunnel_{Deep to}(ii) a The third level of quantification is based on the longitudinal influence length L of the large buried depth tunnel construction_{Longitudinal direction}And equivalent section inrush intensity G_{Deep to}Estimating the danger degree W of the outburst disaster on the tunnel face of the large buried depth tunnel_{Deep to}(ii) a The three-level quantization is from the geological block to the section, and from the local part to the whole, the quantization, the evaluation and the treatment are circularly and progressively carried out, and the inrush hidden danger of each section is gradually eliminated.

Description

Three-level cyclic progressive quantification method for sudden surge hidden danger degree of large buried depth tunnel

Technical Field

The invention relates to a quantitative analysis method for the inrush hidden danger degree of tunnels and underground engineering, in particular to a three-level cyclic progressive quantification method for the inrush hidden danger degree of large buried tunnels.

Background

The large buried tunnel has burst disasters, and the macroscopic phenomena are as follows: water gushing or mud gushing, or water gushing and mud gushing and mixing. The degree of the disaster is different and different.

The large buried depth tunnel inrush disaster macroscopic phenomenon corresponds to the hidden danger degree, the possibility of the disaster macroscopic situation can be inferred by quantifying the hidden danger degree, and the hidden danger degree can be inferred by reversing when the disaster macroscopic phenomenon occurs. The method is used for accurately predicting the sudden surge hidden danger of the large buried depth tunnel, and is not only a key for treating the hidden danger, but also a key for excavation decision after treatment.

Traditionally, hidden dangers are quantified only by using certain characteristic numerical values of hydrogeology, if tables 2-6 show that the water inflow amount of the highway tunnel construction technical rules (JTG/T F60-2009) corresponds to the classification of the water inflow and mud inflow disaster degree, the disaster degree is only related to the simple water amount, and the correlation with main factors such as the area size of a tunnel outline and the environmental change of construction disturbance surrounding rocks is not shown, practice proves that the judgment is always out of level due to the fact that the related factors are lost, the accuracy is not high only in the prediction of the simple water inflow hidden dangers, although the correlation is slightly high, and the accuracy is lower if the method is used for the prediction of the mixture of mud inrush and water inflow mud inrush. The traditional method has the problems that one layer of quantization is mainly used to bring loss of a plurality of associated factors, so that the applicability is poor.

Table 1: grading of water and mud gushing disaster degree and water gushing amount

Note: the water amount in the upper table refers to the unit hour water inflow amount in the tunnel.

The large buried depth tunnel gushing disaster is composed of hydrogeology, the size of the outline area of the tunnel, construction disturbance surrounding rock environment change and other main factors, and in order to ensure that quantitative analysis is reliable, the hydrogeology and the environment change factors need to be integrated.

Until now, there is no method for quantitatively estimating the degree of the hidden danger of the sudden surge of the large buried tunnel by combining hydrogeology with environmental variation factors, so that a method for quantitatively estimating the degree of the hidden danger of the sudden surge of the large buried tunnel by combining hydrogeology with environmental variation factors is necessary.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a three-level progressive quantification method for the inrush hidden danger degree of a large buried tunnel. The estimation method can help design and constructors to determine the degree of the inrush hidden danger of the large buried tunnel more scientifically, comprehensively and accurately, and achieves better effect in implementation.

In order to achieve the purpose, the invention adopts the technical scheme that:

a three-level cyclic progressive quantification method for the inrush hidden danger degree of a large buried depth tunnel; when the buried depth h of the tunnel_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called as a large buried depth tunnel; the first-level quantification of the sudden surge hidden danger degree of the large buried depth tunnel is to determine the sudden surge source form coefficient J of the geological block_{Deep to}(ii) a The second level of quantization is to quantize J_{Deep to}The construction disturbance factor of the large buried depth tunnel section is integrated to obtain the inrush intensity G of the equivalent section of the large buried depth tunnel_{Deep to}(ii) a The third level of quantification is based on the longitudinal influence length L of the large buried depth tunnel construction_{Longitudinal direction}And equivalent section inrush intensity G_{Deep to}Estimating the outburst of tunnel face of large buried depth tunnelDegree of danger of disaster W_{Deep to}(ii) a Three-level quantization is performed from a geological block to a section, and from a local part to the whole, so that the quantization, evaluation and treatment are performed circularly and progressively, and the inrush hidden danger of each section is eliminated step by step;

the three-level progressive quantification method specifically comprises the following steps:

step 1, first-layer quantification of the surge hidden danger degree of a large buried depth tunnel; the method comprises the following steps:

(1) definition of large buried depth tunnel

Setting the buried depth of the tunnel by h_{Buried in}Represents; setting the radius of the tunnel excavation profile to be represented by r, and setting the tunnel excavation width to be represented by B;

if 5r is less than or equal to h_{Buried in}Less than or equal to 40r, or less than or equal to 2.5B_{Buried in}The tunnel is called a general buried tunnel when the ratio is less than or equal to 20B;

if h_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called as a large buried depth tunnel;

(2) defining the concept of geological masses

The underground environment of the large buried depth tunnel is complex, changeable and uneven, the composition of the environmental hydrogeological conditions of each area is not necessarily the same, but the range is reduced to a certain degree, and an area with uniform hydrogeological conditions can be found; under the condition of a region with the same hydrogeological conditions, the region can be regarded as a homogeneous geological block, for example, a region with basically consistent water pressure, surrounding rock strength, composition particle size indexes or parameters is regarded as a geological block; the size of a certain geological block is small enough to only occupy certain parts of the large buried depth tunnel and large enough to occupy a certain area of the large buried depth tunnel;

(3) gushing hidden danger degree of large buried depth tunnel of geological block

The gushing hidden danger degree of the large buried depth tunnel of the geological block is in direct proportion to water pressure and in inverse proportion to the surrounding rock strength of the large buried depth tunnel, is related to the grain composition correction coefficient of the surrounding rock, and can be J_{Deep to}The expression is called the sudden surge source form coefficient of the large buried depth tunnel and the sudden surge source form coefficient J of the large buried depth tunnel_{Deep to}The calculation formula of (2) is as follows:

J_{deep to}＝ε_{Deep to}×(P_{Deep water}/R_{Deep wall}) (ii) a In the formula:

J_{deep to}The form coefficient is a sudden surge source form coefficient of a large buried depth tunnel and belongs to a dimensionless quantity index;

ε_{deep to}The correction coefficient is a grain composition correction coefficient of the surrounding rock of the large buried depth tunnel, and belongs to a dimensionless index; for non-fine sand soil and rock, the provisional value is 1.05; the value of the fine sand is 1.15;

P_{deep water}Measuring the water pressure of surrounding rock groundwater at a certain position of the large buried depth tunnel by a unit: MPa;

R_{deep wall}The compressive strength of the axle center of the surrounding rock at a certain position of the large buried depth tunnel is measured by the following units: MPa;

A. if the large buried depth tunnel is a cavity or a karst cave, J is calculated_{Deep to}During value, the values of the water pressure and the surrounding rock strength of the large buried depth tunnel are obtained according to the following method:

① when the large buried tunnel is a pure water-filled cavity, the water pressure in the core area of the cavity is taken out by the water pressure, and the cavity is taken out by the surrounding rock strength of the large buried tunnel

Wall-out 2 meters wall strength;

② when the large buried tunnel is a water-filled mud-filled cavity, the water pressure of the core area is taken by the water pressure cavity, the intensity of the surrounding rock of the large buried tunnel is taken by the intensity of the soil body of the core area of the cavity, and if the intensity value of the soil body is lower than the water pressure, the intensity of the surrounding rock of the large buried tunnel is taken by the intensity of the surrounding rock of the cavity wall 2 meters outwards;

③ when the large buried depth tunnel is a waterless cavity, the water pressure is uniformly 0.5MPa, and the surrounding rock strength of the large buried depth tunnel is 2 meters of the surrounding rock strength of the cavity wall;

B. a large buried depth tunnel hydrogeological data acquisition method comprises the following steps:

the water pressure of underground water and the surrounding rock strength data of the large buried depth tunnel are obtained through actual investigation and test of the large buried depth tunnel:

① obtaining the strength data of the large buried tunnel wall rock by more than one combination of drilling, pit detection, nondestructive detection and advanced prediction by adopting a conventional exploration means, and obtaining or converting the strength of the large buried tunnel wall rock by a compression test, a penetration test, a bearing capacity test and a wave velocity test method;

② obtaining water pressure data by one of drilling drainage and measuring water pressure, pore water pressure measuring instrument measuring water pressure, irrigation or grouting pressure fracturing method measuring water pressure, measuring water level difference and converting into water pressure;

③ deducing the particle composition correction coefficient epsilon of the surrounding rock of the large buried depth tunnel through conventional lithology analysis_{Deep to}。

(4) Surge source form coefficient J of large buried depth tunnel_{Deep to}Quantization and classification of values

Table 2: large buried depth tunnel inrush form type and large buried depth tunnel inrush source form coefficient interval relation table

Step 2: second-level quantification of the degree of the sudden surge hidden danger of the large buried depth tunnel; the method comprises the following steps:

(1) determining equivalent section of large buried depth tunnel

For a circular large buried depth tunnel, see fig. 1, when a large buried depth tunnel surrounding rock of a certain tunnel face of the large buried depth tunnel is excavated, stress-strain adjustment occurs on the cross section of the large buried depth tunnel, and according to the relation of the stress-strain adjustment of the cross section, the cross section of the circular large buried depth tunnel with the adjustment radius range of 5r is determined as an equivalent cross section of the circular large buried depth tunnel, see fig. 2;

for a non-circular large buried depth tunnel, drawing a small circle by taking the center of the section of the large buried depth tunnel as the circle center and the maximum distance between the excavation contour line and the circle center as the radius r, and drawing a large circle by taking the circle center of the small circle as the center and the radius of 5r, wherein the large circle is determined as the equivalent section of the non-circular large buried depth tunnel, and detailed pictures are shown in figures 3 and 4;

(2) partitioning and assigning the equivalent section of the large buried depth tunnel, including the following situations;

① mechanics partition of equivalent section of large buried depth tunnel

The equivalent section of the large buried depth tunnel is divided into three mechanics areas: plastic large deformation zone A_{Deep to}Plastic small deformation zone B_{Deep to}Elastoplastic zone C_{Deep to}For details, seeFIG. 5;

② geometric partition of equivalent section of large buried depth tunnel

Dividing the equivalent section of the large buried tunnel into 25 partitions, wherein the size of each partition is a square of 2r multiplied by 2r, and the 25 geometric partitions are combined to obtain a large square of 10r multiplied by 10r, and a large circle is drawn on the large square with the radius of 5r to be tangent and close to the large circle, so that the large square is also called the equivalent section of the large buried tunnel and is shown in detail in fig. 6;

(3) carrying out mechanical deformation assignment on each equivalent section subarea of the large buried depth tunnel

Determining C according to the statistics of the displacement deformation measurement data of the large buried depth tunnel_{Deep to}The deformation rate of the zone is less than 0.1 mm/d; b is_{Deep to}The deformation rate of the zone is 0.1-1.0 mm/d; a. the_{Deep to}The rate of deformation of the zone is greater than 1.0mm/d, and in severe cases greater than 5.0 mm/d. Assigning values to each equivalent section subarea of the large buried depth tunnel according to the magnitude of the deformation rate, and establishing each subarea assignment table of the equivalent section of the large buried depth tunnel;

A_{deep to}The minimum deformation rate of the region is C_{Deep to}Maximum deformation rate of 10⁺¹Multiple, if C_{Deep to}The magnitude basis of the zone deformation rate is exactly 10, i.e. 10⁺¹Then A is_{Deep to}The deformation rate of the zone is of the order of 10⁺²；A_{Deep to}If the deformation rate of the zone has 2 grades, the median value of the deformation rate grades is (100+ 500)/2-300; b is_{Deep to}Region is located at A_{Deep to}Minimum deformation rate and C_{Deep to}Between the maximum deformation rates of the zones, then B_{Deep to}The median number of magnitudes of deformation rate for the zone is (10+ 100)/2-55;

(4) assignment adjustment of water influence on each equivalent section partition of large buried depth tunnel

The assignment of the water influence of the large buried depth tunnel equivalent section adjusting partition is divided into two types:

the first is to adjust the assignment of the subareas of the row where the tunnel is located according to the importance of the upper part and the lower part, the position of the large buried depth tunnel is taken as a reference, the importance coefficient is taken as 1.0, the subarea coefficient is increased by 0.2 when the subarea coefficient is increased, and the subarea coefficient is decreased by 0.2 when the subarea coefficient is decreased;

the second is to adjust the assignment of the subareas of other columns according to the distance between the subareas and the large buried depth tunnel, and the descending coefficient is 0.2 when the position of the large buried depth tunnel is taken as a reference and is far away from one subarea;

(5) core subdivision and assignment in large buried depth tunnel

The large buried depth tunnel kernel can be subdivided into regions, and can be assigned according to the upper and lower importance values and the percentage value;

(6) the assignment results of each partition of the large buried tunnel are shown in detail in fig. 7;

(7) building the surge intensity of each subarea of the large buried depth tunnel

The inrush strength of each subarea of the large buried depth tunnel is calculated according to the following formula:

Q_{deep i}＝J_{Deep i}×Ν_{Deep i}×ξ_{Deep to}(ii) a In the formula:

Q_{deep i}-intensity of inrush of a zone, representing the degree of significance, dimensionless, of the source form of the inrush of the zone;

J_{deep i}Form factor of large buried depth tunnel surge source corresponding to subarea, J_{Deep i}The value range is J not less than 0_{Deep i}≤10^-1When J is_{Deep i}＞10^-1When, J_{Deep i}The value is uniformly 1 × 10^-1；

Ν_{Deep i}Assigning values to the partitions corresponding to the large buried depth tunnel;

ξ_{deep to}Boundary influence coefficients for partitions of equivalent section of large buried depth tunnel ξ_{Deep to}The values are correspondingly taken according to the following conditions:

① when the partition is a water-filled mud cavity and the partition is on the top of the arch top ξ_{Deep to}Take 1.3, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.20, ξ when the partition is under the tunnel_{Deep to}Taking 1.15;

② when the partition is a cavity filled with water and the partition is on the top of the arch ξ_{Deep to}Take 1.20, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.15, ξ when the partition is under the tunnel_{Deep to}Taking 1.13;

③ when the boundary of the partition is dry cavity, the partitionξ when located on the upper part of the vault_{Deep to}Take 1.15, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.13, ξ when the partition is under the tunnel_{Deep to}Taking 1.05;

④ when the boundary of the partition is a non-cavity, ξ_{Deep to}Taking 1.05;

(8) establishing equivalent section inrush strength formula

Adding the surge intensities of all 25 subareas in the equivalent section of the tunnel to obtain the total surge intensity of the equivalent section of the tunnel,

Q_{deep bus}＝∑Q_{Deep i}＝∑(J_{Deep i}×Ν_{Deep i}×ξ_{Deep to}) (ii) a In the formula:

Q_{deep bus}The total inrush strength of the actual equivalent section of the tunnel is dimensionless;

Q_{deep i}-is the burst strength of the partition, dimensionless;

J_{deep i}The form coefficient of the surge source of the large buried depth tunnel corresponding to the subarea;

ξ_{deep to}The boundary influence coefficient of each partition of the equivalent section of the large buried depth tunnel is obtained;

(9) determining a tunnel reference equivalent section;

when the tunnel equivalent section is 25 subareas, the big buried tunnel surge source form coefficient J_{Deep to}All values are 10^-2When the tunnel is detected, the equivalent section of the tunnel is a reference equivalent section of the tunnel, and the total inrush intensity of the reference equivalent section of the tunnel is 7.86;

(10) inrush severity for establishing equivalent cross section of tunnel

The calculation formula for establishing the inrush intensity of the equivalent section of the large buried depth tunnel is as follows:

G_{deep to}＝(Q_{Deep bus}-Q_{Deep reference})/Q_{Deep reference}＝(Q_{Deep bus}-7.86)/7.86; in the formula:

G_{deep to}The inrush intensity of the equivalent section of the large buried depth tunnel represents that the inrush hidden danger of the actual equivalent section of the tunnel is relatively strong relative to the reference equivalent section of the tunnelThe degree of weakness, which is dimensionless;

Q_{deep reference}The total inrush strength of the equivalent section of the tunnel reference is 7.86;

(11) establishing three-kind unit section

Establishing three types of unit sections including non-surge section, transition section and surge hidden trouble section, wherein the surge intensity G of each unit section_{Deep to}The values are respectively:

non-surge cross section: g is between 100 percent and 100 percent_{Deep to}＜0；

Transition section: g is not less than 0_{Deep to}≤+64％；

General gushing hidden trouble section: +64% < G_{Deep to}≤+900％；

Special inrush hidden trouble section: g_{Deep to}＞+900％；

And step 3: third-level quantification of large buried depth tunnel surge hidden danger degree

The third level quantification of the inrush hidden danger degree of the large buried depth tunnel comprises the following steps:

(1) the concept of surge cell region is proposed

A section of the large buried tunnel is composed of a plurality of equivalent sections, wherein the surge intensity G of the equivalent section of one large buried tunnel_{Deep to}The maximum value is determined after sequencing, the equivalent section is set to represent a certain section, and the degree of the inrush hidden danger of the certain section of the large buried depth tunnel is equal to G_{Deep to}；

If the surge intensity of a large buried tunnel section representing an equivalent section is G_{Deep to}Then, the large buried tunnel inrush unit area is divided into the following cases:

when G is less than or equal to 100 percent_{Deep to}When the value is less than 0, the area is a non-surge area;

when G is more than or equal to 0_{Deep to}When the water content is less than or equal to +64 percent, the water is called a surge transition zone;

when +64% < G_{Deep to}When the water content is less than or equal to +900%, the water is called a general surge hidden trouble area;

when G is_{Deep to}When > +900%, it is called special inrush hidden trouble area;

(2) building basic model for sudden surge disaster outburst of tunnel face of large buried depth tunnel

① general basic model for outburst disaster outburst of large buried tunnel

When each large buried depth tunnel section consists of three surge unit areas, namely a non-surge area, a surge transition area and a surge hidden danger area, a surge disaster always explodes in advance in the surge transition area and does not explode until the tunnel is tunneled deep into the surge hidden danger area, which is shown in detail in fig. 8;

② basic model for outburst disaster outburst of special large buried tunnel

When each large buried depth tunnel section consists of two surge unit areas, namely a non-surge area and a surge hidden danger area, a surge disaster always explodes in advance in the non-surge area close to the surge hidden danger area and does not explode until the tunnel is tunneled deep into the surge hidden danger area, which is shown in detail in fig. 9;

(3) determining longitudinal influence length of construction disturbance

① when the composition of each large buried tunnel section unit area is the same as the general tunnel gushing disaster outburst basic model, the construction is carried out in the gushing transition area, and the longitudinal influence length L of the construction disturbance to the front is_{Longitudinal direction}Comprises the following steps:

when the tunnel is a common buried tunnel, i.e. 5r is less than or equal to h_{Buried in}Less than or equal to 40r or less than or equal to 2.5B and less than or equal to h_{Buried in}When the longitudinal influence length is less than or equal to 20B, the longitudinal influence length is taken according to the related indexes of a common buried depth tunnel, and the longitudinal influence length is not related to a large buried depth tunnel, so the invention is not specially explained;

when the tunnel is a large buried depth tunnel, and 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.7B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

when the tunnel is a large buried depth tunnel, and h_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 2.0B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

② when the composition of each unit area of large buried tunnel segment is consistent with the basic model of burst disaster outburst of special large buried tunnel, the burst transition area must be manually appointed, and construction is carried out in the manually appointed burst transition area, the construction has the longitudinal influence length L on the front_{Longitudinal direction}Comprises the following steps:

when the tunnel is a large buried depth tunnel, and 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.1B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

when the tunnel is a large buried depth tunnel, and h_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 1.3B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

(4) longitudinal influence length L_{Longitudinal direction}Correction of (2)

Influencing the longitudinal length L_{Longitudinal direction}Correcting to obtain a corrected longitudinal influence reference length;

① when the composition of each large buried tunnel section unit area is consistent with the basic model of the outburst disaster outburst of the general large buried tunnel, the longitudinal reference length L is corrected_{Deep repair}The calculation formula of (2) is as follows:

L_{deep repair}＝L_{Longitudinal direction}×(G_{Deep hidden 1}) V (900% -64%); in the formula:

L_{deep repair}-for the corrected longitudinal influence reference length, the unit of measure: rice;

L_{longitudinal direction}Longitudinal impact length, unit of measure: rice; when 40r is used<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.7B §_{Deep to}(ii) a When h is generated_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 2.0B §_{Deep to}(ii) a B is the tunnel excavation width, and r is the tunnel excavation profile radius; §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

G_{deep hidden 1}The piping intensity of the piping hidden danger zone closest to the piping transition zone is free of dimensional quantity;

② when the composition situation of each large buried tunnel segment unit zone is consistent with the basic model of outburst disaster outburst of the special large buried tunnel,

modified longitudinal influence reference length L_{Repair the}The calculation formula of (2) is as follows:

L_{longitudinal direction}Longitudinal impact length, unit of measure: rice; when 40r is used<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.1B §_{Deep to}(ii) a When h is generated_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 1.3B §_{Deep to}(ii) a B is the tunnel excavation width, and r is the tunnel excavation profile radius; §_{Deep to}Adjusting the coefficient for the degree of fragmentation of the surrounding rock, at normal level §_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

G_{deep hidden 1}-the gushing intensity of the gushing hazard zone closest to the gushing transition zone;

(5) determining a calculation formula of the risk degree of the tunnel face outburst and gushing disasters

The corrected longitudinal reference length of the transition area is used for preventing overbreak, and when the residual length is greater than or equal to the corrected longitudinal reference length, no sudden surge disaster occurs, and the danger degree is zero or negative; when the residual length is smaller than the corrected longitudinal reference length, the smaller the residual length is, the larger the danger degree of the outburst inrush disaster is; when the remaining length is equal to 0 meter, the risk degree of the outburst disaster is 100%, and the outburst disaster inevitably occurs, so the risk degree of the outburst disaster on the tunnel face is calculated as:

① when the composition situation of each large buried depth tunnel section unit area is consistent with the basic model of the outburst disaster outburst of the general large buried depth tunnel, the calculation formula is as follows:

W_{deep to}＝(L_{Deep repair}-L_{Deep residue})/L_{Deep repair}(ii) a In the formula:

W_{deep to}As the degree of danger of outburst of the tunnel face, the unit of measurement is: % W_{Deep to}The value is 0-100%;

L_{deep residue}Is the residual length and has a value range of 0 to L_{Deep residue}≤L_{Deep repair}And the measurement unit is as follows: rice;

② when the composition situation of each large buried tunnel segment unit area is consistent with the basic model of the burst disaster outburst of the special large buried tunnel, the calculation formula is as follows:

and 4, step 4: treatment and requantization of hidden trouble amount and circulation are advanced progressively

The method for treating the hidden trouble quantity and circularly and progressively quantizing the hidden trouble quantity comprises the following steps:

(1) assessing the safety state of the current face

A group of large buried depth tunnel analysis unit segments are divided into 4 specific regions: a non-surge hidden trouble region, a surge transition region, a surge hidden trouble region 1 and a surge hidden trouble region 2; the present face position is D_{Deep to}-D_{Deep to}(ii) a If D is_{Deep to}B_{Deep to}＝L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is 0, the tunnel face is in a critical state, and the tunnel face cannot be excavated forwards; if D is_{Deep to}B_{Deep to}>L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is less than 0, the tunnel face is in a safe state, and the tunnel face can be excavated forwards; if D is_{Deep to}B_{Deep to}<L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is more than 0, and the tunnel face is in a dangerous state and needs to be immediately sealed and reinforced; see fig. 10 in detail;

(2) the first circulation treatment is carried out on the surging hidden trouble area in front of the current tunnel face

When D is present_{Deep to}B_{Deep to}≧L_{Deep repair 1}When the tunnel face is in a safe state or a critical state, the surge intensity of the surge hidden trouble area 1 before treatment is G_{Deep hidden before 1}Drawing a treatment target of G_{Deep hidden 1 plan}(ii) a According to G_{Deep hidden 1 plan}The critical radius (H) of the treatment section of the inrush hidden danger area 1 can be reversely estimated according to the step 2_{Deep to}+ r), the critical range for planned remediation, see fig. 11 for detail;

(3) evaluating the treatment effect of the treatment area in front of the tunnel face and making the decision of excavation

When the surge hidden trouble area 1 is treated, the surge intensity is changed to G_{After being deeply hidden by 1}If G is_{After being deeply hidden by 1}>+64%, judging that the treatment quality is unqualified, and supplementing treatment, wherein details are shown in FIG. 12;

if G is_{After being deeply hidden by 1}Less than or equal to +64 percent, and judging the treatment quality to be qualified; after the treatment is qualified, excavation can be carried out, and the section excavation is carried out from D_{Deep to}-D_{Deep to}To C_{Deep to}-C_{Deep to}Corrected reference length and G_{2 deep front}In connection with, C is to be ensured_{Deep to}E_{Deep to}≧L_{Deep repair 2}I.e. the final face of the first cycle excavation can only be excavated to C_{Deep to}-C_{Deep to}The position of the cross section is shown in detail in fig. 13;

(4) beginning the second cycle of treatment, evaluation, excavation

After the excavation of the first cycle treatment area portion, the current face position is advanced to C_{Deep to}-C_{Deep to}And starting the second cycle of treatment, checking the inrush intensity of the second treatment area, if the inrush intensity is qualified, starting the second cycle of excavation, and circulating the process until the inrush hidden danger area is eliminated, and particularly showing in figure 14.

Compared with the prior art, the invention has the following beneficial effects:

1. compared with the prior art, the method can fully consider the comprehensive factors of uneven hydrogeological distribution of the section and the section of the large buried tunnel, the size of the area of the excavation outline, longitudinal and transverse influences caused by excavation and the like, can comprehensively and accurately quantify the inrush hidden danger degree of geological blocks, sections and paragraphs in a layering way, and combines the hidden danger degrees layer by layer, thereby obtaining better effect in implementation and providing a basis for subsequent treatment. Conventionally, the hidden danger degree of a large buried tunnel is judged only by the water quantity index, the judgment conclusion is unreliable because the water inflow quantity changes along with the changes of operation and environment, the danger degree of the sudden inrush disaster on the tunnel face cannot be judged only by the water inflow quantity index, the water inflow quantity index cannot be used for a treatment plan, cannot be used for judging whether the treatment quality is qualified or not, is difficult to be used for excavation decision, and is more difficult to be circularly used for links of quantification, evaluation and treatment.

2. The method of the invention is used for analyzing and treating the hidden danger or disaster of the inrush current, and can obtain better social benefit, economic benefit and ecological benefit.

Drawings

FIG. 1: the invention is a schematic diagram of a semi-empty section of a circular large buried depth tunnel, wherein, the circle represents the excavation outline of the large buried depth tunnel, and the hatching line at the top represents the earth surface;

FIG. 2 is a drawing: for the schematic diagram of the equivalent section of the circular large buried depth tunnel, in the diagram, a small circle represents the excavation profile of the large buried depth tunnel, a large circle represents the equivalent section of the circular large buried depth tunnel, 1 represents the 1-time radius of the excavation profile of the large buried depth tunnel, 2 represents the 2-time radius of the excavation profile of the large buried depth tunnel, 3 represents the 3-time radius of the excavation profile of the large buried depth tunnel, 4 represents the 4-time radius of the excavation profile of the large buried depth tunnel, and 5 represents the 5-time radius of the excavation profile of the large buried depth tunnel;

FIG. 3: the invention is a schematic diagram of an equivalent section of a rectangular large buried depth tunnel, wherein a rectangle represents the actual shape of an excavation profile surface of the large buried depth tunnel, a small circle represents that the rectangular large buried depth tunnel is simplified into a circular tunnel, a large circle represents the equivalent section of the large buried depth tunnel, 1r represents the excavation radius of 1 time of the large buried depth tunnel, 2r represents the excavation radius of 2 times of the large buried depth tunnel, 3r represents the excavation radius of 3 times of the large buried depth tunnel, 4r represents the excavation radius of 4 times of the large buried depth tunnel, and 5r represents the excavation radius of 5 times of the large buried depth tunnel;

FIG. 4 is a drawing: the invention is a schematic diagram of equivalent section of a straight-wall type large buried depth tunnel, wherein a rectangle represents the actual shape of the excavation profile surface of the straight-wall type large buried depth tunnel, a small circle represents that the straight-wall type large buried depth tunnel is simplified into a circular tunnel, a large circle represents the equivalent section of the large buried depth tunnel, 1r represents the excavation radius of 1 time of the large buried depth tunnel, 2r represents the excavation radius of 2 times of the large buried depth tunnel, 3r represents the excavation radius of 3 times of the large buried depth tunnel, 4r represents the excavation radius of 4 times of the large buried depth tunnel, and 5r represents the excavation radius of 5 times of the large buried depth tunnel;

FIG. 5: for the sectional schematic diagram of the deformation rate of the equivalent section of the large buried depth tunnel, in the diagram, the smallest circle represents the excavation outline of the large buried depth tunnel, the largest circle represents the equivalent section of the large buried depth tunnel, the middle circle represents the area with 3 times of excavation radius, 1 represents the 1 time of radius of the excavation outline of the large buried depth tunnel, 2 represents the 2 times of radius of the excavation outline of the large buried depth tunnel, 3 represents the 3 times of radius of the excavation outline of the large buried depth tunnel, 4 represents the 4 times of radius of the excavation outline of the large buried depth tunnel, and 5 represents the 5 times of radius of the excavation outline of the large buried depth tunnel; a. the_{Deep to}The area is the excavation outline range of the large buried depth tunnel and is a plastic large deformation area; b is_{Deep to}The zone is a circular ring formed by circular arcs with the radius of 1 time and the radius of 3 times, and is a small plastic deformation zone; c_{Deep to}The zones being 3 and 5 radiiThe circular ring formed by the circular arcs is an elastic-plastic deformation area;

FIG. 6: in the figure, the numeral 1 represents the excavation radius of a tunnel with 1 time of large buried depth, the numeral 2 represents the excavation radius of a tunnel with 2 times of large buried depth, the numeral 3 represents the excavation radius of a tunnel with 3 times of large buried depth, the numeral 4 represents the excavation radius of a tunnel with 4 times of large buried depth, the numeral 5 represents the excavation radius of a tunnel with 5 times of large buried depth, the small circle represents the excavation profile surface of the tunnel with large buried depth, the large circle represents the circular equivalent section of the tunnel with large buried depth, the middle circle represents the boundary between an elastoplastic zone and a plastic zone, the big square tangent to the round equivalent section of the large buried depth tunnel is called as the square equivalent section of the large buried depth tunnel, the two equivalent sections are collectively called as large buried depth tunnel equivalent sections, the small square tangent to the small circle is one of the large buried depth tunnel equivalent section axisymmetric subareas, and 24 axisymmetric subareas are arranged according to the symmetry principle;

FIG. 7: the diagram is a schematic diagram of the relative amount of mechanical deformation of equivalent section partitions and kernel-subdivided partitions, wherein 4 small rectangles in the middle represent partitions where the large buried depth tunnel profile is located, the other 24 medium rectangles represent equivalent sections and further 24 axisymmetric partitions according to the symmetry principle, the 24 partitions and the partitions where the large buried depth tunnel profile is located together form the equivalent section of the large buried depth tunnel, and the number in each grid represents the relative amount of mechanical deformation;

FIG. 8: the invention relates to a general surge disaster outburst model schematic diagram of a large buried depth tunnel, belonging to a longitudinal section schematic diagram of the large buried depth tunnel, wherein G_{Deep africa}Indicating a non-surge potential region, G_{Deep and too deep}Indicating a surge potential transition region, G_{Deep hidden 1}Indicating a first surge hazard zone, G, adjacent to the surge hazard transition zone_{Deep hidden 2}Indicating a second surge hazard zone, G_{Deep hidden i}Representing an i-th surge hidden danger area;

FIG. 9: the invention discloses a special surge disaster outburst model schematic diagram of a large buried depth tunnel, belonging to a longitudinal section schematic diagram of the large buried depth tunnel, wherein G_{Deep africa}Indicating a non-surge potential region, G_{Deep hidden 1}Indicating a first surge hazard zone, G, adjacent to a non-surge hazard zone_{Deep hidden 2}Indicating a second surge hazard zone, G_{Deep hidden i}Representing an i-th surge hidden danger area;

FIG. 10: the invention discloses a schematic diagram of a group of large buried depth tunnel analysis unit sections, which belongs to a schematic diagram of a longitudinal section of a large buried depth tunnel, wherein a group of unit sections consists of 4 regions: non-surge region, surge hidden danger transition region, surge hidden danger region 1, surge hidden danger region 2, D_{Deep to}-D_{Deep to}The cross section being the current face, G_{Deep hidden before 1}Indicating the intensity of surge in the surge hidden danger area 1 before treatment, G_{Deep hidden 2 front}Representing the intensity of the surge hidden danger area 2 before treatment;

FIG. 11: the invention relates to a schematic diagram of a treatment plan of a first cycle, which belongs to a schematic diagram of a longitudinal section of a large buried depth tunnel, wherein D_{Deep to}-D_{Deep to}The cross section being the current face, B_{Deep to}B_{Deep to}-E_{Deep to}E_{Deep to}The area is a treated area, G_{Deep hidden 1 plan}Indicating that the surge intensity of the surge hidden danger area 1 is to be changed from G_{Deep hidden before 1}Is lifted to G_{Deep hidden 1 plan}，G_{Deep hidden 2 front}Representing the intensity of the surge hidden danger area 2 before treatment;

FIG. 12: the invention is a schematic diagram of the quality of a first circulation surge hidden trouble area 1 which is still unqualified after being treated, and belongs to a longitudinal section schematic diagram of a large buried depth tunnel, wherein G_{After being deeply hidden by 1}Indicating that the surge intensity of the surge hidden trouble area 1 is changed from G_{Deep hidden before 1}Is lifted to G_{After being deeply hidden by 1}，G_{After being deeply hidden by 1}>+64% means that the quality after treatment is still not acceptable, G_{Deep hidden 2 front}Representing the intensity of the surge hidden danger area 2 before treatment;

FIG. 13: the invention discloses a schematic diagram of qualified quality of a first circulation surge hidden danger area 1 after being treated, which belongs to a longitudinal section schematic diagram of a large buried depth tunnel, wherein G in the schematic diagram_{After being deeply hidden by 1}Indicating that the surge intensity of the surge hidden trouble area 1 is changed from G_{Deep hidden before 1}Is lifted to G_{After being deeply hidden by 1}，G_{After being deeply hidden by 1}<+64% means qualified quality after treatment, C_{Deep to}-C_{Deep to}Section denotes the final section of the first cycle planned excavation, G_{Deep hidden 2 front}Representing the intensity of the surge hidden danger area 2 before treatment;

FIG. 14: the invention discloses a schematic diagram of starting second cycle treatment after first cycle excavation, belonging to a longitudinal section schematic diagram of a large buried depth tunnel, wherein a tunnel face is pushed to C_{Deep to}-C_{Deep to}Section plane, G_{Deep hidden 2 front}Indicating the intensity of surge in the surge hidden trouble area 2 before treatment, G_{Deep hidden 3 front}Indicating the intensity of the surge in the subsequent section of the surge hazard 2.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the present invention is not limited to the scope of the present invention.

Example 1

A three-level cyclic progressive quantification method for the inrush hidden danger degree of a large buried depth tunnel; when the buried depth h of the tunnel_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called as a large buried depth tunnel; the first-level quantification of the sudden surge hidden danger degree of the large buried depth tunnel is to determine the sudden surge source form coefficient J of the geological block_{Deep to}(ii) a The second level of quantization is to quantize J_{Deep to}The construction disturbance factor of the large buried depth tunnel section is integrated to obtain the inrush intensity G of the equivalent section of the large buried depth tunnel_{Deep to}(ii) a The third level of quantification is based on the longitudinal influence length L of the large buried depth tunnel construction_{Longitudinal direction}And equivalent section inrush intensity G_{Deep to}Estimating the danger degree W of the outburst disaster on the tunnel face of the large buried depth tunnel_{Deep to}(ii) a The three-level quantization is from the geological block to the section, and from the local part to the whole, the quantization, the evaluation and the treatment are circularly and progressively carried out, and the inrush hidden danger of each section is gradually eliminated.

(1) definition of large buried depth tunnel

if 5r is less than or equal to h_{Buried in}Less than or equal to 40r, or less than or equal to 2.5B_{Buried in}Not more than 20B, the tunnel is called as oneA common buried tunnel;

if h_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called a large buried depth tunnel.

(2) Defining the concept of geological masses

The underground environment of the large buried depth tunnel is complex, changeable and uneven, the composition of the environmental hydrogeological conditions of each area is not necessarily the same, but the range is reduced to a certain degree, and an area with uniform hydrogeological conditions can be found; under the condition of a region with the same hydrogeological conditions, the region can be regarded as a homogeneous geological block, for example, a region with basically consistent water pressure, surrounding rock strength, composition particle size indexes or parameters is regarded as a geological block; a certain geological block has a size which is as small as occupying some parts of the large buried depth tunnel and as large as occupying a certain area of the large buried depth tunnel.

R_{deep wall}The compressive strength of the axle center of the surrounding rock at a certain position of the large buried depth tunnel is measured by the following units: MPa.

A. If the large buried depth tunnel is a cavity or a karst cave, J is calculated_{Deep to}When the value is equal to the preset value,the values of the water pressure and the surrounding rock strength of the large buried depth tunnel are obtained according to the following method:

Wall-out 2 meters wall strength;

③ when the large buried tunnel is a waterless cavity, the water pressure is 0.5MPa uniformly, and the surrounding rock strength of the large buried tunnel is 2 meters outside the cavity wall.

(1) determining equivalent section of large buried depth tunnel

For a circular large buried depth tunnel, see fig. 1, when a large buried depth tunnel surrounding rock of a certain tunnel face of the large buried depth tunnel is excavated, stress-strain adjustment occurs on the cross section of the large buried depth tunnel, and according to the relation of the stress-strain adjustment of the cross section, the cross section of the circular large buried depth tunnel with the adjustment radius range of 5r is determined as an equivalent cross section of the circular large buried depth tunnel, which is detailed in fig. 2.

For the non-circular large buried depth tunnel, the center of the section of the large buried depth tunnel is taken as the circle center, the maximum distance between the excavation contour line and the circle center is taken as the radius r, a small circle is drawn, then the circle center of the small circle is taken as the center, a large circle is drawn with the radius of 5r, and the large circle is determined as the equivalent section of the non-circular large buried depth tunnel, which is detailed in fig. 3 and 4.

(2) Partitioning and assigning the equivalent section of the large buried depth tunnel, wherein the partitioning comprises the following conditions:

① mechanics partition of equivalent section of large buried depth tunnel

The equivalent section of the large buried depth tunnel is divided into three mechanics areas: plastic large deformation zone A_{Deep to}Plastic small deformation zone B_{Deep to}Elastoplastic zone C_{Deep to}See fig. 5 for details.

② geometric partition of equivalent section of large buried depth tunnel

Dividing the equivalent section of the large buried depth tunnel into 25 partitions, wherein the size of each partition is a square of 2r multiplied by 2r, and the 25 geometric partitions are combined to obtain a large square of 10r multiplied by 10r, and the radius of the large square is 5r_{Deep to}A great circle is drawn tangent to and close to the great circle, so that a great square is also called a great buried tunnel equivalent section, and is shown in detail in fig. 6.

Determining C according to the statistics of the displacement deformation measurement data of the large buried depth tunnel_{Deep to}The deformation rate of the zone is less than 0.1 mm/d; b is_{Deep to}Deformation rate of zones is 0.1 to1.0mm/d；A_{Deep to}The rate of deformation of the zone is greater than 1.0mm/d, and in severe cases greater than 5.0 mm/d. And then, assigning values to all the equivalent section partitions of the large buried depth tunnel according to the magnitude of the deformation rate, and establishing an assignment table of all the partitions of the equivalent section of the large buried depth tunnel.

A_{Deep to}The minimum deformation rate of the region is C_{Deep to}Maximum deformation rate of 10⁺¹Multiple, if C_{Deep to}The magnitude basis of the zone deformation rate is exactly 10, i.e. 10⁺¹Then A is_{Deep to}The deformation rate of the zone is of the order of 10⁺²；A_{Deep to}If the deformation rate of the zone has 2 grades, the median value of the deformation rate grades is (100+ 500)/2-300; b is_{Deep to}Region is located at A_{Deep to}Minimum deformation rate and C_{Deep to}Between the maximum deformation rates of the zones, then B_{Deep to}The median number of orders of magnitude of the deformation rate of the zone is (10+ 100)/2-55.

and the second method is to adjust the assignment of the partitions of other columns according to the distance between the large buried depth tunnel and the large buried depth tunnel, and to take the position of the large buried depth tunnel as a reference, to be far away from one partition, and to reduce the coefficient by 0.2.

(5) Core subdivision and assignment in large buried depth tunnel

The large buried depth tunnel kernel can be subdivided into regions, and can be assigned with a percentage value according to the upper and lower importance.

(6) The assignment results of each partition of the large buried tunnel are shown in detail in fig. 7.

Q_{deep i}＝J_{Deep i}×Ν_{Deep i}×ξ_{Deep to}(ii) a In the formula:

① when the partition is a water-filled mud cavity and the partition is on the top of the arch top ξ_{Deep to}Take 1.3, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.20, ξ when the partition is under the tunnel_{Deep to}Take 1.15.

② when the partition is a cavity filled with water and the partition is on the top of the arch ξ_{Deep to}Take 1.20, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.15, ξ when the partition is under the tunnel_{Deep to}Take 1.13.

③ when the partition is a trunk cavity and the partition is on the top of the dome ξ_{Deep to}Take 1.15, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.13, ξ when the partition is under the tunnel_{Deep to}Take 1.05.

④ when the boundary of the partition is a non-cavity, ξ_{Deep to}Take 1.05.

(8) Establishing equivalent section inrush strength formula

Adding the surge intensities of all 25 subareas in the equivalent section of the tunnel to obtain the total surge intensity and the surge intensity of the equivalent section of the tunnel

The formula is calculated as:

Q_{deep i}-is the burst strength of the partition, dimensionless;

ξ_{deep to}And the boundary influence coefficient of each partition of the equivalent section of the large buried depth tunnel.

(9) Determining a reference equivalent section of a tunnel

When the tunnel equivalent section is 25 subareas, the big buried tunnel surge source form coefficient J_{Deep to}All values are 10^-2And then, the equivalent section of the tunnel is the equivalent section of the tunnel reference, and the total inrush strength of the equivalent section of the tunnel reference is 7.86.

(10) Inrush severity for establishing equivalent cross section of tunnel

G_{deep to}The inrush intensity of the equivalent section of the large buried depth tunnel is a relative strength degree of an inrush hidden danger of an actual equivalent section of the tunnel relative to a reference equivalent section of the tunnel, and belongs to dimensionless quantity;

Q_{deep reference}And the total inrush strength of the equivalent section of the tunnel reference is 7.86.

(11) Establishing three-kind unit section

Transition section: g is not less than 0_{Deep to}≤+64％；

General gushing hidden trouble section: +64% < G_{Deep to}≤+900％

Special inrush hidden trouble section: g_{Deep to}＞+900％。

(1) the concept of surge cell region is proposed

A section of the large buried tunnel is composed of a plurality of equivalent sections, wherein the surge intensity G of the equivalent section of one large buried tunnel_{Deep to}The maximum value is determined after sequencing, the equivalent section is set to represent a certain section, and the degree of the inrush hidden danger of the certain section of the large buried depth tunnel is equal to G_{Deep to}。

when G is_{Deep to}> +900%, it is called the special inrush hidden danger zone.

① general basic model for outburst disaster outburst of large buried tunnel

② basic model for outburst disaster outburst of special large buried tunnel

When each large buried depth tunnel section consists of two surge unit areas, namely a non-surge area and a surge hidden danger area, a surge disaster always explodes in advance in the non-surge area close to the surge hidden danger area and does not explode until the tunnel is tunneled deeply into the surge hidden danger area, which is shown in detail in fig. 9.

(3) Determining longitudinal influence length of construction disturbance

when the tunnel is a common buried tunnel, i.e. 5r is less than or equal to h_{Buried in}Less than or equal to 40r or less than or equal to 2.5B and less than or equal to h_{Buried in}When the longitudinal influence length is less than or equal to 20B, the longitudinal influence length is taken according to the related indexes of a common buried depth tunnel, and the longitudinal influence length is not related to a large buried depth tunnel, so the invention is not specially explained.

When the tunnel is a large buried depth tunnel, and 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.7B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2.

When the tunnel is a large buried depth tunnel, and h_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 2.0B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2.

when the tunnel is a common buried tunnel, i.e. 5r is less than or equal to h_{Buried in}Less than or equal to 40r or less than or equal to 2.5B and less than or equal to h_{Buried in}When the longitudinal influence length is less than or equal to 20B, the longitudinal influence length is taken according to the related indexes of the common buried depth tunnel, and the longitudinal influence length is not related to the large buried depth tunnel, so the method does not adopt the methodSpecific description is given.

When the tunnel is a large buried depth tunnel, and 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.1B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2.

When the tunnel is a large buried depth tunnel, and h_{Buried in}>100r or h_{Buried in}>50B, longitudinal influence length L_{Longitudinal direction}Is 1.3B §_{Deep to}B is the tunnel excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2.

(4) Longitudinal influence length L_{Longitudinal direction}Correction of (2)

G_{deep hidden 1}-isThe gushing intensity of the gushing hidden danger area closest to the gushing transition area is free of dimensional quantity.

② when the composition of each unit area of large buried tunnel is consistent with the basic model of burst disaster outburst of special large buried tunnel, the corrected longitudinal influence reference length L_{Repair the}The calculation formula of (2) is as follows:

G_{deep hidden 1}The gushing intensity of the gushing hazard zone closest to the gushing transition zone.

L_{deep residue}Is the residual length and has a value range of 0 to L_{Deep residue}≤L_{Deep repair}And the measurement unit is as follows: and (4) rice.

(1) assessing the safety state of the current face

A group of large buried depth tunnel analysis unit segments are divided into 4 specific regions: a non-surge hidden trouble region, a surge transition region, a surge hidden trouble region 1 and a surge hidden trouble region 2; the present face position is D_{Deep to}-D_{Deep to}；

If DB is equal to L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is 0, the tunnel face is in a critical state, and the tunnel face cannot be excavated forwards; if DB>L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is less than 0, the tunnel face is in a safe state, and the tunnel face can be excavated forwards; if D is_{Deep to}B_{Deep to}<L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is more than 0, and the tunnel face is in a dangerous state and needs to be immediately sealed and reinforced; see fig. 10 for details.

For example, a tunnel of Guangxi Zhongchang tunnel 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}Less than or equal to 50B, 4 specific areas of a large buried depth tunnel section and a hydrogeology complex section, and data after three-layer quantization are as follows: non-surge hidden trouble area, G_{Deep africa}-50% of surge transition region, G_{Deep and too deep}+ 30%, inrush hidden danger area 1, G_{Deep hidden 1}450%, inrush hidden danger area 2, G_{Deep hidden 2}300%, B12.75 m, §_{Deep to}The value is 1.0; the current tunnel face position is D_{Deep to}-D_{Deep to}，D_{Deep to}B_{Deep to}Total water inflow was 35 cubic meters per hour, 5 meters.

At this point, according to the method of the invention: l is_{Longitudinal direction}＝1.7B§_{Deep to}，L_{Deep repair}＝L_{Longitudinal direction}×(G_{Deep hidden 1}) (900% -64%)/(900% -64%) is 1.7 × 12.75 × 1.0 × 450%/(900% -64%) is 11.67 m; w_{Deep to}＝(11.67-5)/11.67＝57％。

The method of the invention for the present D_{Deep to}-D_{Deep to}For the face of the palm, D_{Deep to}B_{Deep to}5m, D_{Deep to}B_{Deep to}<L_{Deep repair 1}I.e. 5m<11.67 m, and the quantitative value of the risk degree of sudden surge disaster is W_{Deep to}57%, the danger degree of the tunnel face outburst and burst disaster is more than 0, the tunnel face is in a dangerous state, and the tunnel face needs to be immediately sealed and reinforced;

the traditional method judges according to the conditions in the table 1, the total water inflow is 35 cubic meters per hour, and Q is more than 4_{Deep to}In the interval less than or equal to 41, the disaster is characterized as a small disaster, and for the current D_{Deep to}-D_{Deep to}For the face of the tunnel, the degree of danger of outburst of the gushing disaster cannot be determined.

The actual situation is that: excavating to D_{Deep to}-D_{Deep to}The tunnel face has the symptoms that the precursor of the sudden surge disaster continuously appears, the tunnel deformation is increased, the water inflow is increased, surrounding rocks on the tunnel face fall particles and fall blocks densely, the condition is very dangerous, and the tunnel face passes through the tunnel face laterImmediately closing and reinforcing the tunnel face to prevent the outburst of the surge disaster.

According to actual conditions, compared with the traditional method, the method of the invention can accurately predict the danger degree of the tunnel face outburst and gust disasters and can provide a coping method, while the traditional method only qualitatively determines the front hidden danger degree, cannot judge the danger degree of the tunnel face outburst and gust disasters at present and cannot provide a coping method.

When D is present_{Deep to}B_{Deep to}≧L_{Deep repair 1}When the tunnel face is in a safe state or a critical state, the surge intensity of the surge hidden trouble area 1 before treatment is G_{Deep hidden before 1}Drawing a treatment target of G_{Deep hidden 1 plan}(ii) a According to G_{Deep hidden 1 plan}The critical radius (H) of the treatment cross-section of the surge hazard zone 1 can be estimated_{Deep to}+r_{Deep to}) I.e. the critical range of the section for planned treatment; see figure 11 for details.

For example, a tunnel of Guangxi Zhongchang tunnel 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}Less than or equal to 50B, 4 specific areas of a large buried depth tunnel section and a certain section of a hydrogeology complex section, and the data after three-layer quantization are as follows: non-surge hidden trouble area, G_{Deep africa}-50% of surge transition region, G_{Deep and too deep}+ 30%, inrush hidden danger area 1, G_{Deep hidden 1}450%, inrush hidden danger area 2, G_{Deep hidden 2}300%, B12.75 m, §_{Deep to}The value is 1.0; advancing tunnel face position to D_{Deep to}-D_{Deep to}，D_{Deep to}B_{Deep to}The total water inflow is 35 cubic meters per hour, the precursor of the sudden surge disaster continuously appears, the deformation of the tunnel is increased, the water inflow is increased, surrounding rocks on the tunnel face fall off and fall densely, the situation is very dangerous, the tunnel face is closed and reinforced immediately afterwards, and the tunnel face is retreated, D_{Deep to}B_{Deep to}The phenomenon of the precursor of the sudden surge disaster disappears when the water inflow is 12 meters, and the total water inflow is 40 cubic meters per hour.

At this point, according to the process of the invention, D is now_{Deep to}B_{Deep to}12 m, L_{Longitudinal direction}＝1.7B§_{Deep to}，L_{Deep repair}＝L_{Longitudinal direction}×(G_{Deep hidden 1}) L (900% -64%) -1.7 × 12.75 × 1.0 × 450%/(900% -64%) -11.67 m, D_{Deep to}B_{Deep to}≧L_{Deep repair 1}Namely 12 meters ≧ 11.67 meters, the tunnel face is in a safe state, and the surge intensity of the surge hidden trouble area 1 before treatment is G_{Deep hidden before 1}450%, and in order to achieve the treatment effect, the treatment target is G_{Deep hidden 1 plan}Must be less than or equal to + 64%; according to G_{Deep hidden 1 plan}And (4) the critical radius (H) of the treatment section of the inrush hidden danger area 1 can be estimated reversely by adopting the step 2 when the value is +64%_{Deep to}+r_{Deep to}) I.e. the critical range of the section for which treatment is planned.

Making a judgment according to the conditions in Table 1 by a conventional method, and withdrawing the palm surface, D_{Deep to}B_{Deep to}The precursor phenomenon of the sudden surge disaster disappears when the water inflow is 12 meters, the total water inflow is increased from 35 cubic meters per hour to 40 cubic meters per hour, and the water inflow is more than 4 and less than Q_{Deep to}The interval less than or equal to 41 is still qualified as a small disaster, but for the treatment of the inrush hidden danger area 1, the water inrush quantity is controlled to be a qualified index, so that an answer is difficult to give, and a clear method and a scheme are difficult to determine how to estimate the section critical range of planned treatment.

Compared with the traditional method, the method provided by the invention carries out first-cycle treatment on the inrush hidden danger area in front of the tunnel face, and regarding the planned treatment quality and the planned treatment range, the method provided by the invention has definite paths, schemes and answers, but the traditional method is difficult to provide the planned treatment quality and the planned treatment range, and has no answer.

After the surge hidden trouble area 1 is treated, the surge intensity is changed into G_{After being deeply hidden by 1}If G is_{After being deeply hidden by 1}>And +64%, judging that the treatment quality is unqualified, and supplementing treatment; see fig. 12 in detail; if G is_{After being deeply hidden by 1}Less than or equal to +64 percent, and judging the treatment quality to be qualified; after the treatment is qualified, the excavation can be carried out, namely the excavation is carried out from step D_{Deep to}-D_{Deep to}To C_{Deep to}-C_{Deep to}Corrected reference lengthAnd G_{Deep hidden 2 front}In connection with, C is to be ensured_{Deep to}E_{Deep to}≧L_{Deep repair 2}I.e. the final face of the first cycle excavation can only be excavated to C_{Deep to}-C_{Deep to}The position of the cross section; see figure 13 for details.

For example, a tunnel of Guangxi Zhongchang tunnel 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}Less than or equal to 50B, the data is obtained by treating 4 specific areas of a certain section of a hydrogeology complex section, and three-layer quantization, wherein the 4 specific areas are a large buried depth tunnel section: non-surge hidden trouble area, G_{Deep africa}-50% of surge transition region, G_{Deep and too deep}+ 30%, inrush hidden danger area 1, G_{After being deeply hidden by 1}+ 45%, inrush hidden danger area 2, G_{Deep hidden 2}300%, B12.75 m, §_{Deep to}The value is 1.0, and the total water inflow is 14 cubic meters per hour.

For the method of the present invention, after the surge hidden trouble area 1 is treated, G is used_{After being deeply hidden by 1}+ 45%, i.e. G_{After being deeply hidden by 1}Less than or equal to +64 percent, and judging the treatment quality to be qualified; after the treatment is qualified, excavation can be carried out, and the section excavation is carried out from D_{Deep to}-D_{Deep to}To C_{Deep to}-C_{Deep to}When the formula L_{Deep repair 2}＝L_{Longitudinal direction}×(G_{Deep hidden 1}) /(900% -64%) of "G_{Deep hidden 1}"should be" G of surge hazard zone 2_{Deep hidden 2}", i.e., L_{Longitudinal direction}＝1.7B§_{Deep to}，L_{Deep repair 2}1.7 × 12.75 × 1.0 × 300%/(900% -64%) 7.78 m, ensuring that C is present_{Deep to}E_{Deep to}≧ 7.78 m.

For the traditional method, after the sudden surge hidden trouble area 1 is treated, the total water inflow is reduced from the original 35 cubic meters per hour to 14 cubic meters per hour, the judgment is carried out according to the conditions in the table 1, and the total water inflow is more than 4 and less than Q_{Deep to}And in the interval less than or equal to 41, the disaster is identified as a small disaster, the property of the inrush hidden danger area 1 is still not transformed, and the treatment quality is unqualified.

The actual situation is that the construction site considers that the surge hidden danger area 1 is qualified in treatment quality after being treated, excavation is determined, and the tunnel face is pushed to C_{Deep to}-C_{Deep to}，C_{Deep to}E_{Deep to}8.5 m, i.e. make C_{Deep to}E_{Deep to}Not less than 7.78 meters, the whole excavation process is safe, and neither sudden surge disasters nor pre-warning conditions of the sudden surge disasters appear.

According to the actual situation, compared with the effects respectively obtained by the method and the traditional method, the method of the invention evaluates and makes excavation decisions on the treatment effect of the treatment area in front of the tunnel face at present, the method of the invention is more consistent with the actual situation, and the traditional method is difficult to judge the treatment quality effect and cannot provide decision data for excavation.

(4) Beginning the second cycle of treatment, evaluation, excavation

See fig. 14, a section of Guangxi Zhongchang tunnel, 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}Less than or equal to 50B, the data is obtained by treating 4 specific areas of a certain section of a hydrogeology complex section, and three-layer quantization, wherein the 4 specific areas are a large buried depth tunnel section: non-surge hidden trouble area, G_{Deep africa}50% of surge transition zone front section G_{Deep and too deep}30%, and a surge transition zone rear section G_{Deep and too deep}(45%), inrush hidden danger area 1 has been modified, inrush hidden danger area 2, G_{Deep hidden 2}＝+300％，B_{Deep to}12.75 meters, §_{Deep to}A value of 1.0, C_{Deep to}E_{Deep to}The total water inflow was 14 cubic meters per hour, 8 meters.

For the process of the invention, C_{Deep to}E_{Deep to}8.5 m, now C_{Deep to}E_{Deep to}Not less than 7.78 m, and C is judged at present_{Deep to}-C_{Deep to}The tunnel face is safe, although the hidden trouble exists in the surging hidden trouble area 2, the current tunnel face cannot burst the surging disaster, and the second cycle of treatment can be started.

For the traditional method, the judgment is carried out according to the conditions in the table 1, and the total water inflow is more than 4 and less than Q_{Deep to}In the interval less than or equal to 41, the disaster is characterized as small disaster, but for the current C_{Deep to}-C_{Deep to}Whether the tunnel face has burst disasters or not cannot be judged.

The actual situation is that: when the face is pushed to C_{Deep to}-C_{Deep to}There is no outburst disaster or the pre-warning of the outburst disaster.

Compared with the traditional method and the method, the judgment of the method is consistent with the actual situation, one link of the method is tightly buckled with the next link, the loop serves the next loop, and the loop can be advanced; in the traditional method, the judgment is carried out according to the conditions in the table 1, the surging property of the front surging hidden danger area 2 can only be qualitatively determined, the safety and the danger of the current tunnel face cannot be judged, the data of the first cycle and the data of the second cycle are not strongly connected, and the cycle progression is difficult to realize.

Claims

1. A three-level cyclic progressive quantification method for the degree of the inrush hidden danger of a large buried depth tunnel is characterized in that when the buried depth h of the tunnel is large, the three-level cyclic progressive quantification method is adopted_{Buried in}>40r, or h_{Buried in}>20B, the tunnel is called as a large buried depth tunnel; the first-level quantification of the sudden surge hidden danger degree of the large buried depth tunnel is to determine the sudden surge source form coefficient J of the geological block_{Deep to}(ii) a The second level of quantization is to quantize J_{Deep to}The construction disturbance factor of the large buried depth tunnel section is integrated to obtain the inrush intensity G of the equivalent section of the large buried depth tunnel_{Deep to}(ii) a The third level of quantification is based on the longitudinal influence length L of the large buried depth tunnel construction_{Longitudinal direction}And equivalent section inrush intensity G_{Deep to}Estimating the danger degree W of the outburst disaster on the tunnel face of the large buried depth tunnel_{Deep to}(ii) a The three-level quantization is from a geological block to a section, and from a local part to a whole, the quantization, evaluation and treatment are circularly and progressively carried out, and the inrush hidden danger of each section is gradually eliminated, and the method comprises the following specific steps:

(1) definition of large buried depth tunnel

(2) defining the concept of geological masses

The underground environment of the large buried depth tunnel is complex, changeable and uneven, the composition of the environmental hydrogeological conditions of each area is not necessarily the same, but the range is reduced to a certain degree, and an area with uniform hydrogeological conditions can be found; under the condition of a region with the same hydrogeological conditions, the region can be regarded as a homogeneous geological block, and the region with basically consistent water pressure, surrounding rock strength, composition particle size indexes or parameters is regarded as a geological block; the size of a certain geological block is small enough to only occupy certain parts of the large buried depth tunnel and large enough to occupy a certain area of the large buried depth tunnel;

J_{deep to}=ε_{Deep to}×（P_{Deep water}/R_{Deep wall}) (ii) a In the formula:

① when the large buried tunnel is a pure water-filled cavity, the water pressure of the core area of the cavity is taken by the water pressure, and the surrounding rock strength of the large buried tunnel is taken by the surrounding rock strength of 2 meters outwards of the cavity wall;

③ deducing the particle composition correction coefficient epsilon of the surrounding rock of the large buried depth tunnel through conventional lithology analysis_{Deep to}；

(1) determination of equivalent section of large buried depth tunnel

For a circular large buried depth tunnel, when a large buried depth tunnel surrounding rock on a certain tunnel face of the large buried depth tunnel is excavated, stress-strain adjustment occurs on the section of the large buried depth tunnel, and the section of the circular large buried depth tunnel with the adjustment radius range of 5r is determined as the equivalent section of the circular large buried depth tunnel according to the section stress-strain adjustment relation;

for a non-circular large buried depth tunnel, drawing a small circle by taking the center of the section of the large buried depth tunnel as the circle center and the maximum distance between an excavation contour line and the circle center as the radius r, and drawing a large circle by taking the circle center of the small circle as the center and the radius of 5r, wherein the large circle is determined as the equivalent section of the non-circular large buried depth tunnel;

(2) partitioning and assigning the equivalent section of the large buried depth tunnel

Partitioning and assigning the equivalent section of the large buried depth tunnel, wherein the partitioning comprises the following conditions:

① mechanics partition of equivalent section of large buried depth tunnel

The equivalent section of the large buried depth tunnel is divided into three mechanics areas: plastic large deformation zone A_{Deep to}Plastic small deformation zone B_{Deep to}Elastoplastic zone C_{Deep to}；

② geometric partition of equivalent section of large buried depth tunnel

Dividing the equivalent section of the large buried depth tunnel into 25 partitions, wherein the size of each partition is a square of 2r multiplied by 2r, and the 25 geometric partitions are combined to obtain a large square of 10r multiplied by 10r, and a large circle is drawn on the large square with the radius of 5r to be tangent and close to the large circle, so the large square is also called the equivalent section of the large buried depth tunnel;

Determining C according to the statistics of the displacement deformation measurement data of the large buried depth tunnel_{Deep to}Rate of deformation of zoneLess than 0.1 mm/d; b is_{Deep to}The deformation rate of the zone is 0.1-1.0 mm/d; a. the_{Deep to}The deformation rate of the area is more than 1.0mm/d, and when the deformation rate is serious, the deformation rate is more than 5.0mm/d, then the value is assigned to each equivalent section subarea of the large buried depth tunnel according to the magnitude of the deformation rate, and each subarea value assignment table of the equivalent section of the large buried depth tunnel is established;

A_{deep to}The minimum deformation rate of the region is C_{Deep to}Maximum deformation rate of 10⁺¹Multiple, if C_{Deep to}The magnitude basis of the zone deformation rate is exactly 10, i.e. 10⁺¹Then A is_{Deep to}The deformation rate of the zone is of the order of 10⁺²；A_{Deep to}The deformation rate of the zone has 2 grades, and the median number of the deformation rate grades is (100+500)/2 = 300; b is_{Deep to}Region is located at A_{Deep to}Minimum deformation rate and C_{Deep to}Between the maximum deformation rates of the zones, then B_{Deep to}The median number of orders of magnitude of deformation rate of the zone is (10+100)/2 = 55;

(5) core subdivision and assignment in large buried depth tunnel

(6) the assignment result of each partition of the large buried depth tunnel;

Q_{deep i}= J_{Deep i}×Ν_{Deep i}×ξ_{Deep to}(ii) a In the formula:

③ when the partition is a trunk cavity and the partition is on the top of the dome ξ_{Deep to}Take 1.15, ξ when the partition is at the same elevation as the tunnel_{Deep to}Take 1.13, ξ when the partition is under the tunnel_{Deep to}Taking 1.05;

(8) establishing equivalent section inrush strength formula

Adding the inrush intensities of all 25 subareas in the equivalent section of the tunnel to obtain the total inrush intensity of the equivalent section of the tunnel, wherein the calculation formula is as follows:

Q_{deep bus}=∑Q_{Deep i}=∑（J_{Deep i}×Ν_{Deep i}×ξ_{Deep to}) (ii) a In the formula:

Q_{deep i}-is the burst strength of the partition, dimensionless;

(9) determining a reference equivalent section of a tunnel

(10) inrush severity for establishing equivalent cross section of tunnel

G_{deep to}=（Q_{Deep bus}-Q_{Deep reference}）/Q_{Deep reference}=（Q_{Deep bus}-7.86)/7.86; in the formula:

(11) establishing three-kind unit section

Transition section: g is not less than 0_{Deep to}≤+64%；

General gushing hidden trouble section: +64% < G_{Deep to}≤+900%；

Special inrush hidden trouble section: g_{Deep to}＞+900%；

(1) the concept of surge cell region is proposed

① general basic model for outburst disaster outburst of large buried tunnel

When each large buried depth tunnel section consists of three surge unit areas, namely a non-surge area, a surge transition area and a surge hidden danger area, surge disasters always burst in advance in the surge transition area and do not burst until tunneling deeply penetrates into the surge hidden danger area;

② basic model for outburst disaster outburst of special large buried tunnel

When each large buried depth tunnel section consists of two surge unit areas, namely a non-surge area and a surge hidden danger area, a surge disaster always explodes in advance in the non-surge area close to the surge hidden danger area and does not explode until the tunnel is tunneled deeply into the surge hidden danger area;

(3) determining longitudinal influence length of construction disturbance

when the tunnel is a common buried tunnel, i.e. 5r is less than or equal to h_{Buried in}Less than or equal to 40r or less than or equal to 2.5B and less than or equal to h_{Buried in}When the length is less than or equal to 20B, the longitudinal influence length is taken according to the related indexes of the common buried tunnel;

when the tunnel is a large buried depth tunnel, and 40r<h_{Buried in}Less than or equal to 100r or 20B<h_{Buried in}When the length is less than or equal to 50B, the length L is longitudinally influenced_{Longitudinal direction}Is 1.1B §_{Deep to}And B is a tunnelRoad excavation width, r is the tunnel excavation profile radius, §_{Deep to}Adjusting the coefficient, general degree § for the degree of fragmentation of the surrounding rock_{Deep to}A value of 1.0, in severe cases §_{Deep to}The value is 1.2;

(4) longitudinal influence length L_{Longitudinal direction}Correction of (2)

L_{deep repair}=L_{Longitudinal direction}×（G_{Deep hidden 1}) V (900% -64%); in the formula:

L_{deep repair}= L_{Longitudinal direction}×（G_{Deep hidden 1}) V (900% -64%); in the formula:

W_{deep to}=（L_{Deep repair}-L_{Deep residue}）/ L_{Deep repair}(ii) a In the formula:

W_{deep to}As the degree of danger of outburst of the tunnel face, the unit of measurement is: % W_{Deep to}The value is 0～100%；

(1) assessing the safety state of the current face

A group of large buried depth tunnel analysis unit segments are divided into 4 specific regions: a non-surge hidden trouble region, a surge transition region, a surge hidden trouble region 1 and a surge hidden trouble region 2; the present face position is D_{Deep to}-D_{Deep to}(ii) a If D is_{Deep to}B_{Deep to}=L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is 0, the tunnel face is in a critical state, and the tunnel face cannot be excavated forwards; if D is_{Deep to}B_{Deep to}>L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is less than 0, the tunnel face is in a safe state, and the tunnel face can be excavated forwards; if D is_{Deep to}B_{Deep to}<L_{Deep repair 1}The danger degree of the tunnel face outburst gushing disaster is more than 0, and the tunnel face is in a dangerous state and needs to be immediately sealed and reinforced;

When D is present_{Deep to}B_{Deep to}≧L_{Deep repair 1}When the tunnel face is in a safe state or a critical state, the surge intensity of the surge hidden trouble area 1 before treatment is G_{Deep hidden before 1}Drawing a treatment target of G_{Deep hidden 1 plan}(ii) a According to G_{Deep hidden 1 plan}The critical radius (H) of the treatment section of the inrush hidden danger area 1 can be reversely estimated according to the step 2_{Deep to}+r_{Deep to}) I.e. the critical range of planned treatment;

When the surge hidden trouble area 1 is treated, the surge intensity is changed to G_{After being deeply hidden by 1}If G is_{After being deeply hidden by 1}>And +64%, judging that the treatment quality is unqualified, and supplementing treatment;

if G is_{After being deeply hidden by 1}Less than or equal to +64 percent, and judging the treatment quality to be qualified; after the treatment is qualified, excavation can be carried out, and the section excavation is carried out from D_{Deep to}-D_{Deep to}To C_{Deep to}-C_{Deep to}Corrected reference length and G_{2 deep front}In connection with, C is to be ensured_{Deep to}E_{Deep to}≧L_{Deep repair 2}I.e. the final face of the first cycle excavation can only be excavated to C_{Deep to}-C_{Deep to}The position of the cross section;

(4) beginning the second cycle of treatment, evaluation, excavation

After the excavation of the first cycle treatment area portion, the current face position is advanced to C_{Deep to}-C_{Deep to}And starting the second cycle of treatment, inspecting the inrush intensity of the second treatment area, if the inrush intensity is qualified, starting the second cycle of excavation, and circulating the process until the inrush hidden danger area is eliminated.