Tunnel excavation support system based on multi-source data

Abstract

The application relates to the technical field of tunnel construction, in particular to a tunnel excavation support system based on multi-source data, which comprises the following units: a preliminary spraying detection unit, which is used for preliminary spraying of concrete on the surface of surrounding rock; an anchor rod installation unit, which is used for determining the anchor rod installation position to install the anchor rod and collecting the installation pressure and grouting amount in the anchor rod installation process; an anchor rod early warning unit, which is used for determining the water seepage risk grade of the surrounding rock position and determining the corresponding strategy according to the water seepage risk grade; an anchor rod monitoring unit, which comprises a temperature detection subunit and a displacement detection subunit; and a support early warning unit, which is used for judging whether the fixation of the anchor rod meets the preset standard or determining the reason according to the change value of the resistivity. The application utilizes the cooperation of the above units to effectively detect the water seepage position in the tunnel support process, and further improves the accuracy and stability of the tunnel excavation support system based on multi-source data.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel construction, and particularly relates to a tunnel excavation support system based on multi-source data. BACKGROUND

[0002] The tunnel with high groundwater content needs to solve the problems of support and water stop at the same time. The grouting channel of the hollow anchor rod can inject cement slurry or chemical slurry, which can anchor the surrounding rock and block the water seepage channel. The hollow anchor rod is often used as a support means to form a water stop curtain with a pipe shed. When the tunnel passes through a fault zone, a strongly weathered rock layer or a sandy pebble stratum, the self-stability of the surrounding rock is poor, and collapse is easy to occur. Groundwater is easy to seep through the cracks formed by the collapse. The hollow anchor rod can fill the cracks of the surrounding rock through high-pressure grouting to form a grouting reinforcement ring, and at the same time, the anchor rod body provides tensile support to improve the integrity of the surrounding rock.

[0003] Chinese patent application publication No. CN115324591A discloses a kind of saturated soft loess tunnel sub-department precipitation-support comprehensive construction method, which provides a kind of saturated soft loess tunnel sub-department precipitation-support comprehensive construction method, first outside precipitation well is used to cooperate with water stop curtain to carry out overall precipitation, then tunnel is unfolded, sub-department precipitation, excavation, support construction cycle, and the cycle is short and orderly, the initial support of "spraying anchor net" combination is strong and powerful;Precipitation well gives consideration to precipitation and observation function, which is convenient for real-time control of underground water level;Considering that the tunnel arch foot is easy to collapse and lose stability in soft soil layer, the tunnel arch bottom soil body is reinforced by using pipe pile of sand and stone, and a complete set of scientific and reasonable comprehensive precipitation-support construction method is formed by following "advance precipitation, sub-department excavation, short footage, strong support, fast cycle", which improves the engineering properties of saturated soft loess by one-step precipitation, and cooperates with timely excavation and appropriate support measures to improve the stability of surrounding soil layer, reduce total settlement and differential settlement of ground surface, and slow down the settlement consolidation rate of tunnel base stratum, which has the advantages of compact and reasonable sequence, improves the engineering properties of saturated soft soil layer, and ensures the safety and orderly progress of tunnel construction.

[0004] However, the above method has the following problems: it is unable to accurately judge the seepage condition in the process of tunnel construction support, and needs to be used in cooperation with an external precipitation well, causing waste of construction resources. SUMMARY

[0005] Therefore, the present application provides a tunnel excavation support system based on multi-source data to overcome the problem that the prior art is unable to accurately judge the seepage condition in the process of tunnel construction support, and needs to be used in cooperation with an external precipitation well, causing waste of construction resources.

[0006] To achieve the above-mentioned purpose, the present application provides a tunnel excavation support system based on multi-source data, which comprises:

[0007] A primary spraying detection unit is configured to spray concrete on a surrounding rock surface and obtain resistivity and surrounding rock pressure of a plurality of initial points in a primary spraying layer;

[0008] An anchor rod installation unit is connected to the primary spraying detection unit and configured to determine an anchor rod installation position based on the resistivity and an anchor rod support model, install the anchor rod, and collect installation pressure and grouting amount during the installation of the anchor rod;

[0009] An anchor rod early warning unit is connected to the anchor rod installation unit and configured to determine a water seepage risk level of a corresponding surrounding rock position of the anchor rod based on installation characteristic values and determine a corresponding strategy based on the water seepage risk level;

[0010] An anchor rod monitoring unit is connected to the anchor rod early warning unit and, under the condition that the anchor rod is completed grouting, includes a temperature detection subunit arranged in each anchor rod to monitor a temperature value in the anchor rod and a displacement detection subunit arranged at an end of the anchor rod to obtain a displacement of the anchor rod position;

[0011] A support early warning unit is connected to the primary spraying detection unit and the anchor rod monitoring unit and configured to, when it is determined that the fixation of the anchor rod does not meet a preset standard based on anchor rod firmness characteristic values, determine whether the fixation of the anchor rod meets the preset standard based on a secondary determination of an anchor rod axial force change rate, or determine a cause based on a change value of the resistivity, wherein the cause includes surrounding rock water seepage and surrounding rock collapse.

[0012] Further, the installation characteristic values are determined by collecting installation pressure, grouting amount, and unit time pressure fluctuation rate during the installation of the anchor rod.

[0013] Further, the anchor rod early warning unit determines a water seepage risk level of a corresponding surrounding rock position of the anchor rod based on the installation characteristic values and a plurality of preset installation characteristic values.

[0014] Further, the corresponding strategy includes,

[0015] If the water seepage risk level is a first water seepage risk level, the grouting is performed again by changing a slurry ratio;

[0016] If the water seepage risk level is a second water seepage risk level, intermittent grouting is performed by changing the slurry ratio;

[0017] If the water seepage risk level is a third water seepage risk level, a water seepage anchor rod is taken as a center, a permeable pipe is buried, a grouting hole is arranged, and a waterproof curtain is formed by performing staged grouting.

[0018] Further, the support early warning unit determines that the anchoring of the anchor rod has a risk of not meeting the preset standard according to a comparison result that the anchoring firmness value of the anchor rod is greater than or equal to a first preset firmness value, and the first preset firmness value is positively correlated with a depth from the ground to a tunnel top surface.

[0019] Further, the support early warning unit determines whether the anchoring of the anchor rod meets the preset standard according to the anchor rod axial force under the condition that the anchoring firmness value of the anchor rod is greater than or equal to the first preset firmness value and less than a second preset firmness value, and the support early warning unit performs water seepage early warning and determines the reason why the anchoring of the anchor rod does not meet the preset standard according to the change value of the electrical resistivity under the condition that the anchoring firmness value of the anchor rod is greater than or equal to the second preset firmness value, the second preset firmness value is positively correlated with the depth from the ground to the tunnel top surface, and the first preset firmness value is less than the second preset firmness value.

[0020] Further, the anchoring firmness value of the anchor rod is determined by a pressure change value of the surrounding rock pressure, a temperature change value of an anchor rod internal temperature value, and a displacement change value of an anchor rod position.

[0021] Further, the support early warning unit determines whether the anchoring of the anchor rod meets the preset standard according to the anchor rod axial force change rate, wherein,

[0022] If the anchor rod axial force change rate is less than a preset axial force change rate, it is determined that the anchoring of the anchor rod meets the preset standard;

[0023] If the anchor rod axial force change rate is greater than or equal to the preset axial force change rate, it is determined that the anchoring of the anchor rod does not meet the preset standard, a water seepage early warning is issued, and radial grouting is performed with the water seepage anchor rod as the center;

[0024] The preset axial force change rate is positively correlated with the depth from the ground to the tunnel top surface.

[0025] Further, the support early warning unit determines the reason why the anchoring of the anchor rod does not meet the preset standard according to the change value of the electrical resistivity, wherein,

[0026] If the change value of the electrical resistivity is less than a preset electrical resistivity change value, it is determined that the reason why the anchoring of the anchor rod does not meet the preset standard is water seepage of the surrounding rock;

[0027] If the change value of the electrical resistivity is greater than or equal to the preset electrical resistivity change value, it is determined that the reason why the anchoring of the anchor rod does not meet the preset standard is collapse of the surrounding rock;

[0028] The preset electrical resistivity change value is positively correlated with the depth from the ground to the tunnel top surface.

[0029] Further, the displacement detection subunit collects the displacement amounts of the anchor rod and each adjacent anchor rod through a remote sensor, and calculates an average value of the displacement amounts as a displacement change value of the corresponding anchor rod.

[0030] Compared with the prior art, the beneficial effects of the present application are that the present application determines the anchor rod installation position by combining the resistivity and anchor rod support model to install the anchor rod, increases the installation density of the anchor rod at the surrounding rock position with a risk of water seepage by combining the past anchor rod installation experience, simultaneously converts the multi-source data into quantifiable support decision basis, reduces the resource waste caused by blind installation of the anchor rod, and effectively improves the accuracy and stability of the tunnel excavation support system based on multi-source data.

[0031] Further, the present application generates installation characterization values by collecting the installation pressure and grouting amount in the anchor rod installation process to determine the water seepage risk level of the corresponding surrounding rock position of the anchor rod, determines the corresponding strategy according to the water seepage risk level, the traditional experience method often appears over-supporting or insufficient supporting, and the data-driven strategy can accurately locate the risk area, converts the construction process data into quantifiable risk control basis, and further improves the accuracy and stability of the tunnel excavation support system based on multi-source data.

[0032] Further, the present application generates anchor rod firmness characterization values by combining the surrounding rock pressure after the anchor rod completes grouting, the temperature value in the anchor rod, and the displacement value of the anchor rod to determine whether the installation of the anchor rod is qualified, avoids single parameter misjudgment, the traditional single parameter detection needs multiple retests, and the multi-parameter comprehensive evaluation can complete the judgment in a relatively short time, saves the detection cost, accurately locates the defects to reduce the rework amount, reduces the misjudgment rate by using the relevance between parameters, realizes the improvement of the anchor rod installation quality, and accurately determines the surrounding rock situation around the anchor rod, further improves the accuracy and stability of the tunnel excavation support system based on multi-source data.

[0033] Further, the present application accurately locates and analyzes whether the tunnel wall has water seepage by detecting a plurality of parameters in the initial spraying concrete and anchor rod construction process, simultaneously improves the detection efficiency, constructs a whole-chain management and control system of “construction process-seepage risk-disposal strategy” through multi-dimensional detection and fusion analysis of the initial spraying concrete and anchor rod construction parameters, converts the discrete construction data into locatable and quantifiable waterproof decision basis, realizes the upgrading from experience waterproofing to digital waterproofing, and further improves the accuracy and stability of the tunnel excavation support system based on multi-source data. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 The structural block diagram of the tunnel excavation support system based on multi-source data of the present application is shown in the figure;

[0035] Figure 2Logic diagram for determining the water seepage risk level of the present application;

[0036] Figure 3 Logic diagram for determining the anchoring condition of the present application;

[0037] Figure 4 Logic diagram for determining the reason why the anchoring of the present application does not meet the preset standard. DETAILED DESCRIPTION

[0038] In order to make the objects and advantages of the present application clearer, the present application will be further described below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0039] The preferred embodiments of the present application will be described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application and are not used to limit the protection scope of the present application.

[0040] It should be noted that, in the description of the present application, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings, which is only for the convenience of description and does not indicate or imply that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0041] In addition, it should also be noted that, in the description of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] Please refer to Figure 1 As shown in the structure block diagram of the tunnel excavation support system based on multi-source data of the present application, the present application provides a tunnel excavation support system based on multi-source data, which comprises:

[0043] The initial spraying detection unit sprays concrete on the surface of the surrounding rock and obtains the resistivity of a plurality of initial points in the initial spraying layer and the surrounding rock pressure;

[0044] The anchor rod installation unit is connected with the initial spraying detection unit, and is used to determine the anchor rod installation position in combination with the resistivity and the anchor rod support model to install the anchor rod, and collect the installation pressure and the grouting amount in the anchor rod installation process;

[0045] The anchor rod early warning unit is connected with the anchor rod installation unit, and is used for determining a water seepage risk level of a position of the corresponding surrounding rock of the anchor rod according to the installation characteristic value and determining a corresponding strategy according to the water seepage risk level.

[0046] The anchor rod monitoring unit is connected with the anchor rod early warning unit, and comprises a temperature detection subunit arranged in each anchor rod for monitoring a temperature value in the anchor rod and a displacement detection subunit arranged at an end of the anchor rod for acquiring a position of the anchor rod under the condition that grouting of the anchor rod is completed.

[0047] The support early warning unit is connected with the initial spraying detection unit and the anchor rod monitoring unit respectively, and is used for determining whether the fixation of the anchor rod meets the preset standard according to a change rate of the anchor rod axial force twice under the condition that the fixation of the anchor rod does not meet the preset standard according to the anchor rod fixation characteristic value, or determining a reason according to a change value of the resistivity, wherein the reason includes water seepage of the surrounding rock and collapse of the surrounding rock.

[0048] It can be understood that the surrounding rock pressure is a pressure applied by the surrounding rock on the initial spraying layer.

[0049] It can be understood that the displacement detection subunit detects the positions of the anchor rods through a drone, installs a wireless positioning tag at the end of the anchor rod in the area where the support is completed, receives a tag signal of the wireless positioning tag through the drone or a handheld receiving device, calculates three-dimensional coordinates of the tag, generates initial coordinates, continues to collect the tag signal to generate new three-dimensional coordinates, and compares the initial coordinates with the new three-dimensional coordinates to obtain an offset.

[0050] It can be understood that the anchor rod axial force is converted into a resistance change through a strain gauge (sensitivity coefficient 2.0-2.2) pasted on the surface of the anchor rod, and is converted into the axial force after being measured by a Wheatstone bridge.

[0051] Specifically, the anchor rod installation position is determined by combining the resistivity and the anchor rod support model in the present application, the installation density of the anchor rods is increased for the surrounding rock positions with a water seepage risk by combining the past anchor rod installation experience, and the multi-source data is converted into quantifiable support decision basis, so that the resource waste caused by blind installation of the anchor rods is reduced, and the accuracy and stability of the tunnel excavation support system based on the multi-source data are effectively improved.

[0052] Specifically, the installation characteristic value is determined by collecting the installation pressure, the grouting amount and the pressure fluctuation rate per unit time in the anchor rod installation process.

[0053] In the embodiment, the installation characteristic value is calculated by the following formula:

[0054] ;

[0055] wherein, and is the weight coefficient, the installation pressure can directly reflect whether the anchor rod and the surrounding rock are closely attached, the grouting amount can reflect the size of the surrounding rock pores around the anchor rod, the pressure fluctuation in the installation process may reflect the loosening of the surrounding rock, which can lead to the appearance of new pores, and generally , , P is the installation pressure (MPa), is the design pressure (MPa), is the design grouting amount (L), is the pressure fluctuation rate per unit time, is the installation representation value, and only the numerical value is taken when the above formula is calculated.

[0056] Specifically, the installation pressure and the grouting amount in the anchor rod installation process are collected to generate an installation representation value to determine the water seepage risk level of the surrounding rock position corresponding to the anchor rod, and a corresponding strategy is determined according to the water seepage risk level. The traditional experience method often appears over-supporting or insufficient supporting, and the data-driven strategy can accurately locate the risk area, and the construction process data is converted into a quantifiable risk control basis, which further improves the accuracy and stability of the tunnel excavation and support system based on multi-source data.

[0057] Please refer to Figure 2 , which is a logic diagram for determining the water seepage risk level of the present application. The anchor rod early warning unit determines the water seepage risk level of the surrounding rock position corresponding to the anchor rod according to the installation representation value and a plurality of preset installation representation values in turn, wherein,

[0058] If the installation representation value is less than the first preset installation representation value, the water seepage risk level of the surrounding rock position corresponding to the anchor rod is determined to be the first water seepage risk level; if the installation representation value is greater than or equal to the first preset installation representation value and less than the second preset installation representation value, the water seepage risk level of the surrounding rock position corresponding to the anchor rod is determined to be the second water seepage risk level;

[0059] If the installation representation value is greater than or equal to the second preset installation representation value, the water seepage risk level of the surrounding rock position corresponding to the anchor rod is determined to be the third water seepage risk level.

[0060] The first preset installation representation value is less than the second preset installation representation value and both are positively correlated with the depth from the ground to the tunnel top surface.

[0061] In one specific embodiment, the first preset installation representation value is set to 0.3, the second preset installation representation value is set to 0.6, and if the installation representation value is 0.18, which is less than the first preset installation representation value, the water seepage risk level of the surrounding rock position corresponding to the anchor rod is determined to be the first water seepage risk level.

[0062] If the installation characteristic value is 0.47, which is greater than the first preset installation characteristic value and less than the second preset installation characteristic value, it is determined that the water seepage risk level of the anchor rod corresponding to the surrounding rock position is the second water seepage risk level;

[0063] If the installation characteristic value is 0.74, which is greater than the second preset installation characteristic value, it is determined that the water seepage risk level of the anchor rod corresponding to the surrounding rock position is the third water seepage risk level;

[0064] It can be understood that the greater the depth of the tunnel top surface from the ground, the greater the shrinkage force of the tunnel inner wall, and the greater the pressure and grouting amount used for installing the anchor rod. Therefore, the first preset installation characteristic value and the second preset installation characteristic value are positively correlated with the depth of the tunnel top surface from the ground.

[0065] Preferably, the first preset installation characteristic value is selected from the range of (0.2, 0.4), and the second preset installation characteristic value is selected from the range of (0.5, 0.7).

[0066] Specifically, the corresponding strategies include,

[0067] If the water seepage risk level is the first water seepage risk level, the slurry ratio is changed to re-grout.

[0068] If the water seepage risk level is the second water seepage risk level, the slurry ratio is changed and intermittent grouting is performed.

[0069] If the water seepage risk level is the third water seepage risk level, a water permeable pipe is buried around the water seepage anchor rod, and a grouting hole is arranged to perform staged grouting to form a waterproof curtain.

[0070] It can be understood that the first water seepage risk level corresponds to a scene with relatively minor water seepage hazards. The water seepage channels of this level are mostly small gaps between the anchor rod and the hole wall, and local cracks that are not completely filled. The channels are small in size, few in number, and have no continuous high water pressure to push the water seepage. Only the sealing ability of the slurry itself needs to be enhanced to block the channels. The second water seepage risk level corresponds to a scene with medium development of water seepage channels. The channels have certain connectivity, and continuous grouting once will result in incomplete filling due to the rapid loss of slurry. In addition, the high mobility of the slurry may be dispersed by water pressure, which cannot effectively seal. Therefore, intermittent grouting is adopted. The third water seepage risk level corresponds to a scene with extremely high water seepage risk. There are through water seepage channels, and water can continuously supplement through the channels. The core function of the water permeable pipe is to actively drain and reduce pressure, and to guide the high water pressure seepage out through the water permeable pipe, thereby reducing the local water pressure around the anchor rod and avoiding the dispersion of the slurry by water during grouting. The purpose of arranging the grouting hole is to expand the sealing range and gradually cut off the water seepage channels from the periphery to the center, so as to avoid sealing only the local part and missing the deep cracks, and finally form a waterproof curtain.

[0071] Please refer to Figure 3As shown, it is a logic diagram for determining the fixing condition of the anchor rod, and the support warning unit determines that the fixing of the anchor rod has a risk of not meeting the preset standard according to the comparison result that the anchor rod firmness representation value is greater than or equal to the first preset firmness representation value, and the first preset firmness representation value is positively correlated with the depth of the tunnel top surface from the ground.

[0072] Specifically, the support warning unit determines whether the fixing of the anchor rod meets the preset standard according to the anchor rod axial force under the condition that the anchor rod firmness representation value is greater than or equal to the first preset firmness representation value and less than the second preset firmness representation value, and the support warning unit performs water seepage warning and determines the reason why the fixing of the anchor rod does not meet the preset standard according to the change value of the resistivity under the condition that the anchor rod firmness representation value is greater than or equal to the second preset firmness representation value, and the second preset firmness representation value is positively correlated with the depth of the tunnel top surface from the ground, and the first preset firmness representation value is less than the second preset firmness representation value.

[0073] Specifically, the anchor rod firmness representation value is determined by the pressure change value of the surrounding rock pressure, the temperature change value of the anchor rod internal temperature value, and the displacement change value of the anchor rod position.

[0074] In this embodiment, the anchor rod firmness representation value is calculated by the following formula:

[0075] ;

[0076] wherein, , and are weight coefficients, generally taken as , , , is the pressure change value (MPa) of the surrounding rock pressure, is the surrounding rock pressure (MPa), is the temperature change value (℃) of the anchor rod internal temperature value, is the initial temperature (℃) of the anchor rod, is the displacement change value (mm) of the anchor rod position, is the maximum allowable displacement (mm), is the anchor rod firmness representation value, and only the numerical value is taken when the above formula is calculated.

[0077] In a specific embodiment, it is set that is 0.3 MPa, is 10℃, is 8 mm, is 0.12 MPa, is 8℃, is 2 mm, then the anchor rod firmness representation value S is 0.42.

[0078] In a specific embodiment, the first preset firmness representation value is set as 0.5, the second preset firmness representation value is set as 1.2, if the anchor rod firmness representation value is 0.42, which is less than the first preset firmness representation value, it is determined that the fixing of the anchor rod meets the preset standard;

[0079] If the anchor rod firmness representation value is 0.84, which is greater than the first preset firmness representation value and less than the second preset firmness representation value, it is determined whether the fixing of the anchor rod meets the preset standard according to the anchor rod axial force twice.

[0080] If the anchor rod firmness representation value is 1.56, which is greater than the second preset firmness representation value, a water seepage warning is given, and it is determined that the reason why the fixing of the anchor rod does not meet the preset standard according to the change value of the resistivity.

[0081] It can be understood that the greater the depth of the tunnel top surface from the ground, the greater the surrounding rock pressure, the lower the initial temperature of the tunnel, the greater the temperature change value after grouting, and the greater the probability and amplitude of displacement of the surrounding rock, so the first preset firmness representation value and the second preset firmness representation value are positively correlated with the depth of the tunnel top surface from the ground.

[0082] Preferably, the first preset firmness representation value is selected in the range of (0.4, 0.6), and the second preset installation representation value is selected in the range of (1.1, 1.3).

[0083] Specifically, the anchor rod firmness representation value is generated by combining the surrounding rock pressure after grouting, the temperature value in the anchor rod and the displacement value of the anchor rod, so as to determine whether the installation of the anchor rod is qualified, avoid single parameter misjudgment, traditional single parameter detection needs multiple retests, and multiple parameter comprehensive evaluation can complete the determination in a relatively short time, saves detection cost, accurately locates defects to reduce rework, reduces misjudgment rate by using the correlation between parameters, improves the installation quality of the anchor rod, and accurately determines the surrounding rock condition around the anchor rod, further improves the accuracy and stability of the tunnel excavation and support system based on multiple source data.

[0084] Specifically, the support warning unit determines whether the fixing of the anchor rod meets the preset standard according to the anchor rod axial force change rate twice, wherein,

[0085] If the anchor rod axial force change rate is less than the preset axial force change rate, it is determined that the fixing of the anchor rod meets the preset standard;

[0086] If the anchor rod axial force change rate is greater than or equal to the preset axial force change rate, it is determined that the fixing of the anchor rod does not meet the preset standard, a water seepage warning is given, and radial grouting is performed around the water seepage anchor rod.

[0087] The preset axial force change rate is positively correlated with the depth of the tunnel top surface from the ground.

[0088] In a specific embodiment, the anchor rod axial force change rate is set to 20%, if the anchor rod axial force change rate is 18% and is less than the preset axial force change rate, it is determined that the fixing of the anchor rod meets the preset standard;

[0089] If the anchor rod axial force change rate is 32% and is greater than the preset axial force change rate, it is determined that the fixing of the anchor rod does not meet the preset standard, a water seepage warning is issued, and radial grouting is performed with the water seepage anchor rod as the center.

[0090] It can be understood that the greater the depth of the tunnel top surface from the ground, the greater the probability of displacement of the surrounding rock, and the greater the water seepage amount, so the preset axial force change rate is positively correlated with the depth of the tunnel top surface from the ground.

[0091] Preferably, the preset axial force change rate is selected in the range of (10%, 25%).

[0092] Referring to FIG. 6, Figure 4 FIG. 6 is a logic diagram for determining the reason why the fixing of the anchor rod does not meet the preset standard, according to the change value of the resistivity, as shown in the drawing, the support warning unit determines the reason why the fixing of the anchor rod does not meet the preset standard according to the change value of the resistivity, wherein,

[0093] If the change value of the resistivity is less than the preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is water seepage of the surrounding rock;

[0094] If the change value of the resistivity is greater than or equal to the preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is collapse of the surrounding rock;

[0095] In a specific embodiment, the preset resistivity change value is set to 50%, if the change value of the resistivity is 42% and is less than the preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is water seepage of the surrounding rock;

[0096] If the change value of the resistivity is 64% and is greater than the preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is collapse of the surrounding rock;

[0097] The preset resistivity change value is negatively correlated with the depth of the tunnel top surface from the ground.

[0098] It can be understood that the shallower the depth of the tunnel top surface from the ground, the higher the porosity of the overburden layer, the stronger the permeability, and the greater the influence of water seepage on the resistivity, the deeper the depth of the tunnel top surface from the ground, the lower the porosity of the overburden layer, the poorer the permeability, and the smaller the influence of water seepage on the resistivity, so the preset resistivity change value is negatively correlated with the depth of the tunnel top surface from the ground.

[0099] Preferably, the depth of the tunnel top surface from the ground is (0 meters, 50 meters), and the preset resistivity change value is selected in the range of (60%, 80%);

[0100] The depth of the tunnel top surface from the ground is (50 meters, 100 meters), and the selected range of the preset resistivity variation value is (40%, 60%);

[0101] The depth of the tunnel top surface from the ground is (100 meters, 200 meters), and the selected range of the preset resistivity variation value is (20%, 40%).

[0102] Specifically, the displacement detection subunit collects the displacement amounts of the anchor rod and each adjacent anchor rod through the remote sensor, and calculates the average of the displacement amounts as the displacement variation value of the corresponding anchor rod.

[0103] Specifically, the application makes accurate positioning and analysis on whether the tunnel wall has water seepage by detecting a plurality of parameters in the initial concrete spraying and anchor rod construction process, and improves the detection efficiency. Through multi-dimensional detection and fusion analysis of the initial concrete spraying and anchor rod construction parameters, a whole-chain management and control system of “construction process-seepage risk-disposal strategy” is constructed, the discrete construction data is converted into a locatable and quantifiable waterproof decision basis, the upgrade from experience waterproof to digital waterproof is realized, and the accuracy and stability of the tunnel excavation support system based on multi-source data are further improved.

[0104] Thus, the technical solutions of the application have been described in combination with the preferred embodiments shown in the drawings, but it is easy for those skilled in the art to understand that the protection scope of the application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the application, and the technical solutions after the changes or replacements will all fall within the protection scope of the application.

Claims

1. A tunnel excavation support system based on multi-source data, characterized by, The application relates to a tunnel supporting system, which comprises: a primary spraying detection unit, which is used to spray concrete on a surrounding rock surface and acquire the resistivity of a plurality of initial points in a primary spraying layer and the pressure of the surrounding rock; an anchor rod installation unit, which is connected with the primary spraying detection unit and used to determine the anchor rod installation position by combining the resistivity and an anchor rod supporting model to install the anchor rod and collect the installation pressure and the grouting amount during the installation of the anchor rod; an anchor rod early warning unit, which is connected with the anchor rod installation unit and used to determine the water seepage risk grade of the corresponding surrounding rock position of the anchor rod according to installation characteristic values and determine the corresponding strategy according to the water seepage risk grade; an anchor rod monitoring unit, which is connected with the anchor rod early warning unit and comprises a temperature detection subunit arranged in each anchor rod to monitor the temperature value in the anchor rod and a displacement detection subunit arranged at the end of the anchor rod to acquire the position of the anchor rod under the condition that the anchor rod is completed grouting; a supporting early warning unit, which is connected with the primary spraying detection unit and the anchor rod monitoring unit respectively and used to determine whether the fixing of the anchor rod meets the preset standard according to the secondary determination of the anchor rod axial force change rate when it is determined that the fixing of the anchor rod has the risk of not meeting the preset standard according to the anchor rod firmness characteristic value, or determine the reason according to the change value of the resistivity, wherein the reason includes surrounding rock water seepage and surrounding rock collapse; the installation characteristic values are determined by collecting the installation pressure, the grouting amount and the unit time pressure fluctuation rate during the installation of the anchor rod; the anchor rod firmness characteristic values are determined by the pressure change value of the surrounding rock pressure, the temperature change value of the temperature value in the anchor rod and the displacement change value of the position of the anchor rod; if the anchor rod axial force change rate is less than a preset axial force change rate, it is determined that the fixing of the anchor rod meets the preset standard; if the anchor rod axial force change rate is greater than or equal to the preset axial force change rate, it is determined that the fixing of the anchor rod does not meet the preset standard, a water seepage early warning is sent and radial grouting is carried out with the water seepage anchor rod as the center; if the change value of the resistivity is less than a preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is surrounding rock water seepage; if the change value of the resistivity is greater than or equal to the preset resistivity change value, it is determined that the reason why the fixing of the anchor rod does not meet the preset standard is surrounding rock collapse.

2. The multi-source data based tunnel excavation support system of claim 1, wherein, the anchor rod early warning unit determines the water seepage risk grade of the corresponding surrounding rock position of the anchor rod according to the installation characteristic values and a plurality of preset installation characteristic values in sequence.

3. The multi-source data based tunnel excavation support system of claim 2, wherein, the corresponding strategy includes, if the water seepage risk grade is a first water seepage risk grade, the grouting is carried out again by changing the slurry ratio; if the water seepage risk grade is a second water seepage risk grade, intermittent grouting is carried out by changing the slurry ratio; if the water seepage risk grade is a third water seepage risk grade, a water permeable pipe is buried with the water seepage anchor rod as the center, grouting holes are arranged and stage grouting is carried out to form a waterproof curtain.

4. The multi-source data based tunnel excavation support system of claim 3, wherein, the supporting early warning unit determines that the fixing of the anchor rod has the risk of not meeting the preset standard according to the comparison result of the anchor rod firmness characteristic values greater than or equal to a first preset firmness characteristic value, and the first preset firmness characteristic value is positively correlated with the depth of the tunnel top surface from the ground.

5. The multi-source data based tunnel excavation support system of claim 4, wherein, The support early warning unit determines whether the fixation of the anchor rod meets the preset standard according to the secondary judgment of the anchor rod axial force on the condition that the anchor rod firmness representation value is greater than or equal to the first preset firmness representation value and less than the second preset firmness representation value, and the support early warning unit performs water seepage early warning and determines the reason why the fixation of the anchor rod does not meet the preset standard according to the change value of the electrical resistivity on the condition that the anchor rod firmness representation value is greater than or equal to the second preset firmness representation value, the second preset firmness representation value is positively correlated with the depth from the tunnel top surface to the ground, and the first preset firmness representation value is less than the second preset firmness representation value.

6. The multi-source data based tunnel excavation support system of claim 5, wherein, The preset axial force change rate is positively correlated with the depth from the tunnel top surface to the ground.

7. The multi-source data based tunnel excavation support system of claim 6, wherein, The preset electrical resistivity change value is positively correlated with the depth from the tunnel top surface to the ground.

8. The multi-source data based tunnel excavation support system of claim 7, wherein, The displacement detection subunit collects the displacement amounts of the anchor rod and each adjacent anchor rod through a remote sensor, and calculates the average of a plurality of displacement amounts as the displacement change value of the corresponding anchor rod.

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