Method for identifying sudden gushing water source during tunnel construction period based on multi-source information fusion

Abstract

The application discloses a tunnel construction period sudden gushing water source discrimination method based on multi-source information fusion, and specifically comprises the following steps: firstly, according to a daily dynamic curve of tunnel sudden gushing water and H value thereof 3 H value, whether the main supply source of the tunnel sudden gushing water is groundwater static storage is discriminated; according to the water chemical characteristics, isotope characteristics and water temperature characteristics of the tunnel sudden gushing water and groundwater, river water and lake water around the tunnel sudden gushing water, whether the main supply source of the tunnel sudden gushing water is groundwater, river water or lake water is discriminated; water balance analysis is carried out, the supply amount and discharge amount are calculated, and the proportion of each item of the tunnel sudden gushing water supply source is quantitatively discriminated; geological condition analysis is carried out, surface water flow measurement and geophysical exploration are carried out, and the water filling channel of the tunnel sudden gushing water is discriminated. The application provides a method for discriminating the sudden gushing water supply source and the water filling channel when a tunnel under construction encounters a sudden gushing water working condition from the perspective of earth system science, improves the accuracy and work efficiency of water source discrimination, and reduces the tunnel sudden gushing water prevention and investigation cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of tunnel gushing water disaster prevention, and particularly relates to a tunnel construction period gushing water source discrimination method based on multi-source information fusion. BACKGROUND

[0002] Tunnel gushing water problem has always been a difficult problem in tunnel engineering construction and daily safety operation. The identification of gushing water source and water filling channel is the core of solving the tunnel gushing water problem, and plays a decisive role in gushing water quantity prediction, prevention and construction. With the promotion of the western development, the state's investment in the field of infrastructure projects continues to grow, and a large number of highway and railway infrastructure projects are under construction, and the number of tunnel projects is increasing rapidly, and the number of cases of gushing water accidents is increasing. In the past, the research is generally in the tunnel alignment stage, aiming at the proposed tunnel, through the analysis of geological conditions, supplemented by a small amount of survey, to predict the risk of tunnel gushing water. This prediction is qualitative, and the accuracy is also limited. For the in-construction tunnel that has experienced major gushing water, it is necessary to increase the means of work, find out the recharge source and water filling channel of the tunnel gushing water, and provide scientific basis for the prevention of tunnel gushing water. Therefore, this technology has important guiding significance for in-construction tunnels that encounter gushing water conditions.

[0003] The methods for studying the source of tunnel gushing water mainly include hydrogeological drilling method, water chemical isotope analysis method, tracer test method, and geophysical exploration method. The hydrogeological drilling method can directly analyze the water abundance of aquifer and the flow direction of groundwater by uncovering the aquifer, but the cost is high, the construction period is long, and the effect is poor in the strong heterogeneous area of groundwater in the bedrock mountainous area. The tracer test method can describe the type and hydrodynamic parameters of the runoff channel, but it needs rich investigation data support, and only under the condition of basically mastering the water connection channel can better results be obtained, and the cycle is long and the environmental impact is difficult to control. The geophysical exploration method can directly describe the runoff channel, but the interpretation of physical parameters needs the support of geological conditions, and has multiple solutions. The water chemical isotope method is the most commonly used and effective method for identifying the source of tunnel gushing water at present, which identifies the water source through the similarity of characteristics, but this method is a qualitative method and cannot quantify the recharge source, and also has multiple solutions. The discrimination of tunnel gushing water recharge source involves multiple disciplines, and the use of one or several aspects of information often leads to inaccurate conclusions. It is urgent to propose a discrimination method that fuses multi-source information from the perspective of earth system science and based on exact geological principles, to overcome the limitations of single method and improve the accuracy of water source discrimination. Therefore, it is very meaningful to propose a tunnel construction period gushing water source discrimination method based on multi-source information fusion. SUMMARY

[0004] The purpose of the present application is to provide a tunnel construction period sudden gushing water source discrimination method based on multi-source information fusion, which can accurately and efficiently discriminate the tunnel sudden gushing water supply source and water filling channel.

[0005] The technical solution adopted by the present application is a tunnel construction period sudden gushing water source discrimination method based on multi-source information fusion, which specifically comprises the following steps:

[0006] Step 1, collect tunnel daily sudden gushing water data to obtain a tunnel sudden gushing water flow-time (Q-T) process curve; combine the collected data to test the sudden gushing water 3 H value, and discriminate whether the main supply source of the tunnel sudden gushing water is the static storage of underground water;

[0007] Step 2, collect tunnel sudden gushing water and tunnel site area underground water, river water and lake water samples, test water temperature, water chemistry and isotope indexes; obtain water chemistry characteristics, δD-δ 18 O relationship, water temperature characteristics, and further discriminate whether the main supply source of the tunnel sudden gushing water is underground water, river water or lake water;

[0008] Step 3, collect tunnel parameters, meteorological hydrological data, geological structure data, etc. to obtain multi-year average precipitation, tunnel elevation, surrounding river water surface elevation and river water surface width, atmospheric precipitation infiltration coefficient and empirical value of permeability coefficient, etc. water balance calculation parameters; according to the basin where the tunnel is located and the sudden gushing water time, the balance area and balance period are determined; according to the obtained water balance parameters, the atmospheric precipitation infiltration recharge, river water leakage recharge and river water lateral recharge, etc. are calculated; the water balance analysis is carried out to quantify the proportion of each supply source;

[0009] Step 4, use the tunnel parameters, meteorological hydrological data and geological structure data collected in step 3 to analyze the spatial relationship between the water filling channel and the supply source, such as fault, soluble rock and non-soluble rock contact zone, hard rock and soft rock contact zone, etc.; carry out river water section flow measurement affected by the water filling channel, and analyze whether the upstream and downstream river water section flow of the suspected water filling channel is seepage; carry out geophysical exploration in the river water flow seepage obvious section to find out the position of the water filling channel.

[0010] Further, the specific process of step 1 is:

[0011] If the tunnel sudden gushing water QT curve is of the attenuation type, even gradually decreases to close to 0, the 3 H value is less than 2TU, it is determined that the supply source of the tunnel sudden gushing water is mainly the static storage of underground water; if the tunnel sudden gushing water QT curve is of the dynamic stability type, the 3 H value is greater than 2TU, it is determined that the supply source of the tunnel sudden gushing water is mainly the dynamic recharge of underground water, river water or lake water.

[0012] Further, the specific process of step 2 is:

[0013] Step 2.1, according to the pH, TDS, K + , Na + , Ca 2+ , Mg 2+ , HCO3 ﹣ , CO3 2﹣ , SO4 2﹣ and Cl ﹣ mass concentration test results, the molar equivalent concentration is calculated, and the molar equivalent percentage of each ion is calculated, according to the Shukarev classification, the content of anions and cations greater than 25% is combined to determine the water chemical type, and the water chemical type Piper diagram is drawn; The specific calculation formula is as follows:

[0014] (1);

[0015] (2);

[0016] In the formula, N i is the millimolar equivalent concentration of the i-th ion in the water body, meq / L; V i is the valence of the i-th ion, dimensionless; m i is the mass concentration of the i-th ion, mg / L; M i is the relative molecular mass of the i-th ion; A i is the millimolar equivalent percentage of the i-th ion, which is calculated separately for anions and cations;

[0017] Water bodies with similar water chemical characteristics indicate that the two have similar recharge sources;

[0018] Step 2.2, according to the test of different water bodies δD and δ 18 O value, unit is VSMOW, ‰, draw δDδ 18 O scatter plot in excel, where δD is the Y axis, δ 18 O is the X axis, and the global rainwater line is added, the equation is δD=8×δ 18 O+10; analyze the distribution characteristics of different water bodies in the δDδ 18 O scatter plot, water bodies with overlapping or similar positions indicate that the two have similar recharge sources;

[0019] Step 2.3, according to the temperature values of different water bodies tested, draw different water body temperature box plots, and analyze the similarity of the temperature of the tunnel gushing water and other water bodies.

[0020] Further, the specific process of step 3 is:

[0021] Step 3.1, balance item determination; for a tunnel with stable drainage, the recharge items generally include atmospheric precipitation infiltration, river water infiltration recharge, river water lateral recharge, and the discharge item is generally the stable drainage of the tunnel;

[0022] Step 3.2, atmospheric precipitation infiltration Q p , its calculation formula is as follows:

[0023] Q P = 2.74 x a x P x F (3);

[0024] In the formula: P, multi-year average precipitation (mm); a, precipitation infiltration recharge coefficient; F, calculation area (km 2 );

[0025] Step 3.3, when there is river water through the tunnel surface, the vertical river water infiltration recharge Q s needs to be calculated, its calculation formula is as follows:

[0026] (4);

[0027] In the formula: K v , vertical permeability coefficient of aquifer (m / d); L, total length of river elevation higher than tunnel gushing point elevation (m); W, river width (m); M, aquifer thickness (m); H, river water level (m); h, tunnel track surface elevation (m);

[0028] Step 3.4, when there is a river around the tunnel site, and the river water level is higher than the tunnel track surface, the lateral river water recharge Q l needs to be calculated, its calculation formula is as follows:

[0029] Q l = K h x J x M x B (5);

[0030] In the formula: K h , lateral permeability coefficient of aquifer (m / d); J, river water to tunnel hydraulic gradient, dimensionless; M, aquifer thickness (m); B, lateral recharge width of river water (m);

[0031] Step 3.5, stable drainage of the tunnel Q' 排 , read according to the tunnel drainage duration curve;

[0032] Step 3.6, water balance analysis; calculate the total recharge Q 补 = Q p + Q s + Q l , total discharge Q' 排 ;

[0033] If Q补 ≈Q' 排 , then further calculate the proportion of each recharge amount in the total recharge amount η i ;

[0034] η i =Q i / Q 补 , Q i is Q p , Q s , Q l ;

[0035] If Q 补 is much smaller than Q' 排 , then there are other sources of recharge, i.e. river water or lake water flows through pipes / cracks to the tunnel.

[0036] Further, the specific process of step 4 is as follows:

[0037] Step 4.1, analyze the water-filled channel, which is a fault zone;

[0038] According to the geological condition data collected in step 3, determine the soluble rock, hard rock and soft rock existing in the area;

[0039] According to the structural data collected in step 3, determine the distribution of the fault zone in the area;

[0040] Step 4.2, expand the contact zone between soluble rock and non-soluble rock, the contact zone between hard rock and soft rock, the linear strip of the fault zone and the contact position of river water / lake water, and then measure the river flow section, compare the upstream and downstream section flow of the river water, and judge whether there is direct seepage recharge of river water;

[0041] Step 4.3, carry out geophysical exploration in the section where the river flow is obviously seeped, and determine the position of the water-filled channel; in the bedrock mountain area, select magnetotelluric method and transient electromagnetic method; the exploration depth of transient electromagnetic method is concentrated in 300-400 m; the exploration depth of magnetotelluric method is concentrated in 700-800 m.

[0042] Further, the fault zone is one of active fault zone, contact zone between soluble rock and non-soluble rock, contact zone between hard rock and soft rock or core of syncline / anticline.

[0043] Further, the fault zone is an active fault zone.

[0044] Further, the soluble rock is carbonate rock, including limestone, dolomite, siliceous limestone and marl and marble; the hard rock includes magmatic rock, sedimentary rock and metamorphic rock, the magmatic rock includes unweathered-micro weathered granite, diorite and basalt; the sedimentary rock includes ferruginous / calcic cemented conglomerate, sandstone and volcanic rock; the metamorphic rock includes gneiss and quartzite; the soft rock includes shale, mudstone, argillaceous sandstone and reinforced wind-full weathered hard rock.

[0045] The technical scheme of the present application has the following advantages: the present application proposes a tunnel sudden gushing water supply source and water filling channel discrimination method which fuses multiple source information such as tunnel sudden gushing water dynamics, water chemical isotope, temperature analysis, water balance analysis, geological condition analysis and geophysical detection, and fully utilizes the most commonly used and effective method according to the theory of earth system science, from qualitative discrimination of the supply source, quantitative calculation to discrimination of the water filling channel in combination with the geological condition, each step has a definite geological theory basis, and the final tunnel sudden gushing water supply source and water filling channel are obtained. Compared with the method of discriminating the tunnel supply source by using geological condition, water chemical isotope, sudden gushing water dynamics and other information, the sudden gushing water supply source discrimination method proposed by the present application fully considers various information that can be collected, organically fuses various fragmented information, discriminates the tunnel sudden gushing water supply source according to the geological principle and logically and carefully, and quantitatively gives the proportion of each supply source, and overcomes the error of single information, and provides a targeted target for sudden gushing water prevention and treatment of the tunnel under construction. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical scheme in the specific embodiments or prior art of the present application, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0047] Figure 1 The flowchart of the present application is shown in the figure;

[0048] Figure 2 The Q-T curve of the daily tunnel sudden gushing water amount of an important work point of the Sichuan-Tibet traffic corridor provided by the embodiment of the present application is shown in the figure;

[0049] Figure 3 The δD-δ 18 O relationship graph of different water bodies provided by the embodiment of the present application is shown in the figure;

[0050] Figure 4 The temperature box plot of different water bodies provided by the embodiment of the present application is shown in the figure;

[0051] Figure 5 is a river water leakage section magnetotelluric geophysical profile provided by an embodiment of the present application. DETAILED DESCRIPTION

[0052] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0053] EMBODIMENT

[0054] The present embodiment provides a tunnel construction period sudden gushing water source discrimination method based on multi-source information fusion. The method is used to provide construction suggestions for the tunnel construction site, reduce the blindness of tunnel sudden gushing water survey, and thus reduce construction delay and economic loss.

[0055] Taking a certain important tunnel of the Sichuan-Tibet traffic corridor as an example, the technical process is as shown in Figure 1 , and the implementation is specifically performed according to the following steps:

[0056] Step 1, collect the daily sudden gushing water volume data of the tunnel from July 1, 2022 to November 1, 2022, and obtain the tunnel sudden gushing water flow-time process curve, as shown in Figure 2 ; collect the 3 H value of the tunnel sudden gushing water sample once a month.

[0057] The Q-T curve of the tunnel is of a dynamic stable type, and the stable gushing water volume is about 64800 m 3 / d, 3 The H value is 5.6-10.7 TU, which is obviously greater than 2 TU, and belongs to modern water, indicating that the tunnel sudden gushing water supply source is not the static storage of underground water, and may be river water, lake water or shallow underground water.

[0058] Step 2, determine the water chemical characteristics according to the water chemical detection results. The water chemical type of the tunnel sudden gushing water is HCO3-Ca type, the TDS is 53 mg / L, the F - is 2.97 mg / L, which is basically consistent with the characteristics of the Zhedu River water. The water chemical type of the Muzigou River water around the tunnel is HCO3-Ca·Mg type, the TDS is 123 mg / L, the F - is 0.70 mg / L, the water chemical type of the Maojiagou River water is HCO3-Mg·Ca·Na type, the TDS is 300 mg / L, and the F - is 0.32 mg / L. The water chemical type of the surface spring around the tunnel is HCO3-Ca type, the TDS is 41-63 mg / L, and the F -1.02 mg / L. From the water chemical characteristics, the tunnel gushing water is similar to the Zheduo River water and the surrounding shallow groundwater, and is obviously different from the Mosigou River water and the Maojiagou River water. Therefore, the tunnel gushing water supply source is likely to be the Zheduo River water and the tunnel surrounding shallow groundwater.

[0059] According to the isotope detection results, the δD-δ 18 O relationship diagram is shown in FIG. 3. Figure 3 It can be seen from FIG. 3 that the tunnel gushing water sample is located in the lower left of the rainwater line, and the δD, δ 18 O characteristics are similar to the river water and are obviously different from the surface spring water, indicating that the tunnel gushing water is likely to be mainly supplied by the river water, and the proportion of the shallow groundwater supply is small.

[0060] According to the water temperature measurement results, the temperature box plots of different water bodies are drawn, as shown in FIG. 4. Figure 4 The temperature of the river water is 0.60-12.95℃, the temperature of the lake water is 5.90-12.57℃, the temperature of the shallow groundwater is 3.79-14.30℃, the temperature of the deep groundwater exposed by the drill hole is 9.08-26.03℃, and the temperature of the tunnel gushing water is 4.70-6.26℃. The temperature of the tunnel gushing water is obviously lower than the temperature of the deep groundwater exposed by the drill hole. The tunnel depth is about 350m, and according to the data of the nearby drill hole, the ground temperature gradient in the research area is about 2.75℃ / 100m. Therefore, the ground temperature at the tunnel depth should be 9.6℃ higher than the surface air temperature. According to the meteorological monitoring data in the Kangding area, the average annual temperature is 7.30℃. Considering that the altitude of the work area is about 400m higher than that of the meteorological station, the surface temperature of the tunnel is about 4.90℃ after height correction. According to this, the ground temperature at the tunnel depth should be 14.50℃. Obviously, the temperature of the tunnel gushing water is obviously lower than the ground temperature. According to the field investigation, the water temperature of the water well near the tunnel is 11.3℃, which basically conforms to the calculation according to the ground temperature gradient. Therefore, the water temperature of the tunnel gushing water is obviously lower than the temperature of the deep groundwater, and is obviously lower than the calculated temperature of the atmospheric precipitation or the shallow groundwater after the downward infiltration and the heating by the ground temperature. Therefore, the shallow groundwater or the atmospheric precipitation infiltration is not the main supply source of the tunnel gushing water. It is found in the investigation that the water temperature of the Zheduo River water and the lake water in the upstream is <5℃. Therefore, the supply source of the tunnel gushing water is likely to be mainly the direct supply of the Zheduo River water.

[0061] Step 3, the tunnel is located in the Zheduo River basin, the west side is the Mosigou River water, and the east side is the Zheduo River water. No surface water passes through the surface of the tunnel. Therefore, the supply term in the water balance analysis includes the atmospheric precipitation infiltration and the river lateral runoff.

[0062] The calculation of atmospheric precipitation recharge. Field investigation did not find the dry springs and gullies, so the recharge area is delineated according to the surface watershed. According to the data of Kangding weather station, the average annual precipitation since 2010 is 888.97 mm. The strata in the area include granite, clastic rock and Quaternary moraine, alluvial deposits, etc. According to the empirical value of precipitation infiltration coefficient α, the value of α of alluvial deposits in the river channel is 0.25, the value of α of moraine is 0.30, the value of α near the fault zone in the bedrock area and other areas is 0.25 and 0.20 respectively, which are the maximum values within the range of available values. According to formula (3), the atmospheric precipitation recharge is calculated to be 0.84×104m 3 / d.

[0063] The calculation of river water lateral recharge. According to the collected data, the length of the tunnel is about 2000 m, and the track surface elevation is about 3200 m. Therefore, the total recharge width of the river is 2000 m. The water surface elevation of Muzigou is 3420-3810 m, and the water surface elevation of Heodu River is 3210-3410 m, with large elevation change. When calculating the hydraulic gradient and aquifer thickness, it is calculated by segments, and each segment is 100 m. The lithology of the aquifer is granite. According to relevant literature, the permeability coefficient of granite is related to the degree of weathering. The permeability coefficient of each weathering zone is as follows: 0.5-2.3 m / d for fully differentiated layer, 10 -1 m / d for strongly weathered layer, 10 -2 m / d for weakly weathered layer, 10 - 3 m / d for slightly weathered layer, and less than 10 -5 m / d for unweathered layer. The tunnel to Heodu River section is located in the Heodu Lake fault zone, with strong weathering, and the K value is taken as the maximum value of 2.0 m / d. The upper part of the tunnel to Muzigou section is mainly strongly weathered granite, and the lower part is mainly weakly weathered granite, with K value of 0.03. The lateral recharge of Muzigou and Heodu River is calculated to be 1.22×104m 3 / d and 0.15×104m 3 / d respectively.

[0064] Analysis of water balance results. The recharge in the balance area is 2.21×104m 3 / d, and the discharge is 6.48×104m 3 / d, which is in a negative balance state. The tunnel gushing water discharge is much larger than the total recharge, and the regional groundwater level will drop, but the investigation found that the surface spring flow attenuation is not obvious, and the well water level has not decreased significantly, indicating that the tunnel gushing water has other large recharge sources.

[0065] Table 1, water balance analysis results, unit: 104m 3 / d.

[0066]

[0067] Step 4, geological condition analysis. According to the geological map of the area, the main water-conducting structures are Zheduo Tang fault and its branch faults, which are northwest-trending and may conduct river water into the tunnel. First, cross-section flow measurement is carried out in places where the river elevation exceeds the tunnel track surface.

[0068] Table 2, results of river cross-section flow measurement

[0069]

[0070] The downstream section of Maojiagou River has an increase of 5.84% in flow compared with the upstream section, and no obvious leakage section is found.

[0071] The downstream section of Maojiagou River has a decrease of 5.79% in flow compared with the upstream section, and no obvious leakage section is found.

[0072] Zheduo River has 6 cross-sections for flow measurement from the source to the outlet, and all the tributaries along the way are also measured. It is found that between KDA54 and KDA53, the river flow decreases by 23.10%, i.e. 4.41×104m 3 / d, which is far beyond the measurement error, indicating that there is obvious leakage of river water at this place. The lithology of this area is granite, and the rock is broken near the fault zone, which is easy to form runoff channels. Zheduo Tang fault and Mosigou fault are both distributed on the west side of Zheduo River, so the leaked river water mainly runs westward and may flow into the tunnel with a lower track surface elevation.

[0073] Geophysical exploration is carried out in the possible leakage section. Since the depth of measurement is more than 400m, magnetotelluric method is selected.

[0074] Magnetotelluric geophysical profile Figure 5 .

[0075] It can be seen from Figure 5 that the surface layer of 30-50m is a low-resistance zone, which is the granite weathering zone and the thickness of river sediments, and below it is a high-resistance zone, which is the granite bedrock. There is a low-resistance fracture zone under the Zheduo River channel, which extends to the lower left, and the elevation gradually decreases from 3400m to about 3300m. The right side of this elevation is a high-resistance zone, showing the river leakage zone and the runoff zone extending to the lower left, which is consistent with the river leakage zone shown by the surface flow measurement. The elevation of the runoff zone is basically consistent with the track surface elevation of the tunnel (3200-3300m), indicating that there is a runoff channel at the leakage section of Zheduo River, and the river water flows into the tunnel along the runoff zone.

[0076] The measured leakage amount of Zheduo River is 4.41×104m 3 / d, while the water balance analysis estimates the leakage amount of river water to be 4.27×104m 3 / d, with a difference of about 3.27%. The estimated water quantity is basically consistent with the measured water quantity.

[0077] In summary, the main supply source of the tunnel gushing water is the leakage of Heishui River water, accounting for about 65.9% of the total supply, followed by lateral runoff supply of river water, accounting for about 21.2% of the total supply, and the atmospheric precipitation infiltration supply accounts for the smallest proportion, accounting for about 12.9% of the total supply. The water filling channel of river water leakage supply is the northeast-trending tension fracture zone.

Claims

1. A method for identifying a source of sudden gushing water during tunnel construction based on multi-source information fusion, characterized in that, Specifically comprising the following steps: Step 1, collect the tunnel gushing water data day by day, get the tunnel gushing water flow-time (Q-T) process curve; combine the collected data to test the gushing water 3 H value, determine whether the main supply source of the tunnel gushing water is the groundwater static storage; Step 2, collect tunnel gushing water, groundwater, river water and lake water samples in tunnel area, test water temperature, water chemistry and isotope indexes; obtain water chemistry characteristics, δD, δ 18 O relationship, water temperature characteristics, and distinguish the main supply source of tunnel gushing water; Step 3, collecting tunnel parameters, meteorological hydrology, geological structure data, obtaining multi-year average precipitation, tunnel elevation, surrounding river water surface elevation and river water surface width, atmospheric precipitation infiltration coefficient and empirical value of permeability coefficient water balance calculation parameters; according to the river basin where the tunnel is located and the time of sudden gushing water, the balance area and balance period are determined; according to the obtained water balance parameters, the atmospheric precipitation infiltration recharge, river water seepage recharge and river water lateral recharge are calculated; the tunnel stable drainage discharge is calculated; water balance analysis is carried out to quantify the proportion of each recharge source; Step 4, using the tunnel parameters, meteorological hydrology, geological structure data collected in step 3, analyzing the spatial relationship between the fault, the contact zone of soluble rock and non-soluble rock, the contact zone of hard rock and soft rock, the water-filled channel and the recharge source; Developing river flow measurement of the river section affected by the water-filled channel, analyzing whether the upstream and downstream river section flow of the suspected water-filled channel seeps; carrying out geophysical exploration in the river flow seepage section to find out the position of the water-filled channel; The specific process of step 1 is: If the tunnel gushing water QT curve is of the attenuation type, even gradually decreases to close to 0, its 3 If the H value is less than 2TU, it is determined that the tunnel gushing water supply source is mainly the static storage of underground water; if the tunnel gushing water QT curve is of the dynamic stability type, its 3 If the H value is greater than 2TU, it is determined that the tunnel gushing water supply source is mainly the dynamic supply of underground water, river water or lake water. The specific process of step 3 is: Step 3.1, balance item determination; for tunnels with stable drainage, the recharge items generally include atmospheric precipitation infiltration, river water seepage recharge, river water lateral recharge, and the discharge item is generally the tunnel stable drainage; Step 3.2, the amount of rainfall infiltration Q p The calculation formula is as follows: Q P = 2.74 x a x P x F (3); where: P, the average annual precipitation (mm); a, the precipitation infiltration recharge coefficient; F, the area of the calculation region (km 2 ); Step 3.3, when the river water through the tunnel surface, the need to calculate the vertical leakage of river water recharge Q s The formula is as follows: （4）； where: K v , vertical permeability coefficient of aquifer (m / d); L, total length of river elevation higher than tunnel gushing point elevation (m); W, river width (m); M, aquifer thickness (m); H, river water level (m); h, tunnel track surface elevation (m); Step 3.4, when there is a river around the tunnel address area, and the river water level is higher than the tunnel track surface, then the lateral recharge amount Q of the river water is calculated l The calculation formula is as follows: Q l =K h ×J×M×B (5); where: K h , aquifer lateral permeability coefficient (m / d); J, river-to-tunnel hydraulic gradient, dimensionless; M, aquifer thickness (m); B, river lateral recharge width (m); Step 3.5, Tunnelling stable discharge, Q 排 , read from the tunnel discharge-duration curve; Step 3.6, carry out water balance analysis; calculate total recharge Q 补 = Q p + Q s + Q l , total discharge Q' 排 ; If Q 补 ≈ Q' 排 , then further calculate the proportion η i of each supply amount in the total supply amount. η i =Q i / Q 补 , Q i for Q p , Q s , Q l ; If Q 补 is much smaller than Q' 排 , then there are other sources of recharge, i.e. river or lake water flows through the pipes / cracks to the tunnel. The specific process of step 4 is: Step 4.1, analyzing the water-filled channel as a fault zone; According to the geological condition data collected in step 3, determine the soluble rock, hard rock and soft rock existing in the area; According to the structure data collected in step 3, determine the distribution of the fault zone in the area; Step 4.2, expand outward at the contact zone of soluble rock and non-soluble rock, the contact zone of hard rock and soft rock, the linear strip of the fault zone and the contact position of river water / lake water, and then carry out river section flow measurement, compare the upstream and downstream river section flow to determine whether there is direct seepage recharge of river water; Step 4.3, carry out geophysical exploration in the river flow seepage section to determine the position of the water-filled channel; in the bedrock mountain area, select magnetotelluric method and transient electromagnetic method; the exploration depth of transient electromagnetic method is concentrated in 300-400 m; the exploration depth of magnetotelluric method is concentrated in 700-800 m.

2. The method according to claim 1, characterized in that, The specific process of step 2 is: Step 2.1, according to the pH, TDS, K + , Na + , Ca 2+ , Mg 2+ , HCO3 ﹣ , CO3 2﹣ , SO4 2﹣ and Cl ﹣ mass concentration test results, the molar equivalent concentration is calculated, and the molar equivalent percentage of each ion is calculated, according to the Shukarev classification, the anions and cations with a content greater than 25% are combined to determine the water chemical type, and the water chemical type Piper diagram is drawn; The specific calculation formula is as follows: （1）； （2）； wherein N i is the millimolar equivalent concentration of the i-th ion in the water body, meq / L; V i is the valence of the i-th ion, dimensionless; m i is the mass concentration of the i-th ion, mg / L; M i is the relative molecular mass of the i-th ion; A i is the millimolar equivalent percentage of the i-th ion, calculated separately for anions and cations. Water bodies with similar water chemical characteristics indicate that their recharge sources are similar; Step 2.2, δD and δ 18 O values of different water bodies, in VSMOW, ‰, plot δD vs δ 18 O scatter plot with δD as Y axis and δ 18 O as X axis, and add global rainwater line, equation is δD = 8 x δ 18 O + 10; analyze the distribution characteristics of different water bodies in δD vs δ 18 O scatter plot, water bodies with similar locations or similar values indicate similar recharge sources; Step 2.3, draw temperature box plots of different water bodies according to the temperature values of different water bodies, and analyze the similarity of the temperature of the tunnel sudden gushing water and other water bodies.

3. The method according to claim 1, characterized in that, The fault zone is one of active fault zone, contact zone of soluble rock and non-soluble rock, contact zone of hard rock and soft rock or core part of syncline / anticline.

4. The tunnel construction period inrush water source discrimination method based on multi-source information fusion according to claim 3, characterized in that, The fault zone is an active fault zone.

5. The method according to claim 1, characterized in that, The soluble rock is carbonate rock, including limestone, dolomite, siliceous limestone and marl and marble; the hard rock includes magmatic rock, sedimentary rock and metamorphic rock, the magmatic rock includes unweathered-micro weathered granite, diorite and basalt; the sedimentary rock includes iron / calcium cemented conglomerate, sandstone and volcanic rock; the metamorphic rock includes gneiss and quartzite; the soft rock includes shale, mudstone and argillaceous sandstone as well as strengthened weathered-full weathered hard rock.

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