A relay type underground excavation shed structure system and construction method

Abstract

The application discloses a relay type underground excavation shed hole structure system and a construction method, and relates to the technical field of highway engineering; the relay type underground excavation shed hole structure system comprises a main hole structure; the main hole structure adopts the following structure at a slope body excavation section: the main hole structure comprises a group of circular arc arch body structures; the circular arc arch body structures are arranged at intervals; the circular arc arch body structures are connected through a plurality of longitudinal pipes on one side close to the slope body and connected through a special-shaped beam body on the other side; a plurality of relay walls are arranged at intervals on the side close to the slope body of the circular arc arch body structures; and the longitudinal pipe shed penetrates the relay walls; and the top of the special-shaped beam body is provided with a plurality of inclined horizontal steel pipe piles which are punched into the slope body. The relay type underground excavation shed hole structure system aims to form a stable "upper anchoring and lower supporting" bearing structure system through the horizontal steel pipe piles, the relay walls and the longitudinal pipe shed, effectively isolates the disturbance of the underground excavation of the shed hole on the slope body, ensures the stability of the shed hole and the mountain body in the tunnel construction process, and realizes safe and rapid construction of the underground excavation of the shed hole.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of highway engineering, in particular to a relay type underground excavation shed tunnel structure system and a construction method. BACKGROUND

[0002] With the continuous extension of the highway to the western mountainous area, the line inevitably passes through the valley, the side of the mountain and other bias pressure sections. The shed tunnel, as an effective way to pass through the section, has begun to emerge. The traditional shed tunnel generally adopts the construction methods of open cut backfill and half-arch cover excavation. The above construction methods all have a problem: with the excavation of the shed tunnel, the disturbance of the slope body gradually increases, which is easy to cause sliding along the fracture surface during the excavation process, and there is a great safety hazard. The main reason is that the disturbance of the slope body caused by the excavation of the shed tunnel is not controlled in place. Whether it can be researched that a shed tunnel structure and a construction method for effectively controlling the disturbance of the slope body during the underground excavation, so that the shed tunnel can be quickly and safely constructed is a difficult problem to be solved. SUMMARY

[0003] Based on the existing problems, the present application provides a relay type underground excavation shed tunnel structure system and a construction method, which aims to form a stable "upper anchor and lower support" bearing structure system through the transverse steel pipe pile, the relay wall and the longitudinal pipe shed, effectively isolate the disturbance of the slope body caused by the underground excavation of the shed tunnel, ensure the stability of the shed tunnel and the mountain body during the tunnel construction process, and realize the safe and rapid construction of the underground excavation of the shed tunnel.

[0004] The technical scheme adopted by the present application is as follows:

[0005] A relay type underground excavation shed tunnel structure system, which comprises a main tunnel structure, and the main tunnel structure adopts the following structure at the slope body excavation section:

[0006] The main tunnel structure comprises a group of circular arc arch body structures, the circular arc arch body structures are arranged at intervals, the circular arc arch body structures are connected on the side close to the slope body through a plurality of longitudinal pipes, and the other side is connected through a special-shaped beam body; a plurality of relay walls are arranged at intervals on the side close to the slope body of the circular arc arch body, and the longitudinal pipe shed penetrates the relay wall; a plurality of transverse steel pipe piles are installed obliquely into the slope body on the top of the special-shaped beam body;

[0007] The transverse steel pipe pile is connected with the top of the special-shaped beam body to form an anchoring unit, and the anchoring unit realizes the lateral upper anchoring of the main tunnel structure; the plurality of longitudinal pipes form a longitudinal pipe shed, and the longitudinal pipe shed forms a longitudinal bearing unit together with the relay wall; and the longitudinal bearing unit realizes the lower support of the main tunnel structure when the rock mass excavation constraint is lost.

[0008] Further, the circular arc arch body structure comprises a sleeve arch located at the outer circle of the circular arc arch body structure, and a lining layer structure located at the inner circle and the bottom of the circular arc arch body structure.

[0009] Further, the relay wall section is a right trapezoidal wall structure, one side of which extends into the main hole structure, and the other side is embedded with the slope body.

[0010] Further, the special-shaped beam body includes a plurality of inclined columns arranged at intervals along the direction of the shed hole excavation, and a special-shaped joist is mounted at the top of the inclined column, and a bearing platform beam is mounted at the bottom of the inclined column; the special-shaped joist is connected to one side of the circular-arc-shaped arch body structure and the lining layer structure; the special-shaped beam body further includes a plurality of transverse connecting beams arranged at intervals along the direction of the shed hole excavation, and the bearing platform beam is connected to the lining layer structure through the plurality of transverse connecting beams in the main hole structure.

[0011] Further, the special-shaped joist is provided with a crown beam above the main hole structure, and the crown beam is located on the high mountain side of the center line of the main hole structure section, and the crown beam is connected to one end of the transverse steel pipe pile.

[0012] A construction method of a relay type underground excavation shed hole structure, which is based on the above-mentioned shallow-buried bias relay type underground excavation shed hole structure, and includes the following steps:

[0013] Step 1: Excavate the mountain in a small range, clear the operation platform, and set the transverse steel pipe pile towards the slope body, and the transverse steel pipe pile end is poured together with the crown beam;

[0014] Step 2: Further excavate the mountain in a small range, and make the bearing platform beam, the inclined column and the special-shaped joist;

[0015] Step 3: Determine the spacing and number of relay walls according to the geological conditions and the length of the shed hole;

[0016] Step 4: Determine the position of the relay wall based on the spacing and number of the relay wall, mill and pour the relay wall, and reserve a guide pipe at a suitable position of the relay wall during the pouring process, and the top of the relay wall is consistent with the surface slope of the mountain;

[0017] Step 5: Set the longitudinal pipe shed from the position of the arch towards the relay wall, and the pipe shed passes through the relay wall;

[0018] Step 6: Excavate the main hole below the pipe shed and make the lining layer structure;

[0019] Step 7: When the main hole structure is excavated to the relay wall, remove the part of the wall in the main hole according to the tunnel contour by milling, and continue to set the longitudinal pipe shed from the reserved guide sleeve of the relay wall to the next relay wall;

[0020] Step 8: Continue to excavate the main hole below the pipe shed; repeat the above steps until the main hole is through; when setting the longitudinal pipe shed, the upward angle thereof is 1-3°, so that the plurality of longitudinal pipes form an arch shape as a whole.

[0021] Further, in step 3, the spacing of the relay wall is determined as follows:

[0022] Step 3.1, calculate the residual sliding force of the slope:

[0023]

[0024]

[0025]

[0026] In the formula, , , is the residual sliding force of each part of the slope, where represents the first section of the slope, represents the middle section of the slope, represents the tail end of the slope near the main hole structure; is the safety factor; , , is the weight of the potential sliding soil of each part of the slope; , , is the angle between the potential sliding soil of each part of the slope and the horizontal plane; , , is the internal friction angle of each part of the slope; , , is the cohesion of the rock-soil body of each part of the slope; , , is the length of the potential sliding soil of each part of the slope; , is the load transfer coefficient between the slopes, ;

[0027] Step 3.2, calculate the residual sliding force that the bearing unit formed by the relay wall and the longitudinal pipe shed needs to bear:

[0028]

[0029] In the formula, is the residual sliding force that the bearing unit needs to bear; is the distribution coefficient;

[0030] The bearing unit formed by the relay wall and the longitudinal pipe shed is simplified as a single-span hyperstatic beam with fixed connection at both ends. The limit deflection of a single longitudinal pipe under the action of residual sliding force is calculated:

[0031]

[0032]

[0033] wherein, is the residual sliding force borne by a single longitudinal pipe; is the longitudinal pipe layout spacing of the longitudinal pipe shed; is the layout range of the longitudinal pipe shed; is the midspan deflection of the longitudinal pipe shed; is the length of the longitudinal pipe between the relay walls; is the elastic modulus of the longitudinal pipe shed; is the cross-sectional moment of inertia of the longitudinal pipe shed and the grouting body; is the diameter of a single longitudinal pipe;

[0034] Step 3.3, the maximum tensile stress of a single longitudinal pipe under the action of the residual sliding force is calculated as:

[0035]

[0036] wherein, is the maximum tensile stress of a single longitudinal pipe;

[0037] Step 3.4, based on the limit deflection calculation of a single longitudinal pipe and the maximum tensile stress of a single longitudinal pipe, the pipe shed length under the conditions of the limit deflection and the allowable stress of a single longitudinal pipe is calculated respectively 、 ;

[0038]

[0039]

[0040] Step 3.5, the length of a single longitudinal pipe should be taken as the smaller one of 、 ; the length of a single longitudinal pipe is the spacing of the relay walls.

[0041] The beneficial effects of the present application are:

[0042] 1. The relay type underground excavation shed structure system ingeniously connects the shed tunnel arch lining layer structure and the special-shaped beam body into a force whole mainly for transmitting axial force, thereby improving the anti-bias bearing capacity of the main tunnel structure.

[0043] 2. The relay type underground excavation shed structure system utilizes the relay walls to cooperate with the longitudinal pipe shed to form a bearing whole, effectively isolates the disturbance of shallow buried bias shed tunnel excavation to the mountain, and ensures that the mountain stability is not affected during the construction process of the main tunnel structure.

[0044] 3. The relay wall of the relay type tunneling shed structure system is milled and excavated, and the longitudinal main tunnel structure is constructed by tunneling, which greatly reduces the slope excavation area, saves land, and protects the environment. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 It is a schematic diagram of the overall structure of the relay type tunneling shed structure system of the present application;

[0046] Figure 2 It is a schematic diagram of the end surface structure of the relay type tunneling shed structure system of the present application;

[0047] Figure 3 It is a schematic diagram of the structure of the relay wall, longitudinal pipe shed and main tunnel structure of the present application;

[0048] Figure 4 It is a schematic diagram of the local structure of the relay wall and longitudinal pipe shed of the present application;

[0049] Figure 5 It is a schematic diagram of the mechanical analysis of the relay type tunneling shed structure system of the present application;

[0050] Figure 6 It is a cross-sectional view of the relay wall of the present application;

[0051] In the figure, 1 is a circular arc arch structure, 2 is a slope body, 3 is a longitudinal pipe, 4 is a special-shaped beam body, 5 is a relay wall, 6 is a transverse steel pipe pile, 7 is a longitudinal pipe shed, 8 is a sleeve arch, 9 is a lining layer structure, 10 is an inclined column, 11 is a special-shaped joist, 12 is a pile cap beam, 13 is a transverse coupling beam, 14 is a crown beam, and 15 is a guide sleeve. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not 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] In view of the problem that the disturbance control of the slope body in the current shed tunnel excavation process is not in place, the present embodiment provides a relay type tunneling shed structure system, which comprises a main tunnel structure, and the main tunnel structure adopts the following structure in the slope body excavation section:

[0054] As shown in Figure 1 and Figure 2 , the main tunnel structure comprises a set of circular arc arch structures 1, the circular arc arch structures 1 are arranged at intervals, the circular arc arch structures are connected on one side close to the slope body 2 by a plurality of longitudinal pipes 3, and connected on the other side by a special-shaped beam body 4. As shown inFigure 1 、 Figure 2 and Figure 4 As shown in

[0055] Wherein, as shown in Figure 1 The arc-shaped arch structure 1 includes a sleeve arch 8 at the outer circle of the arc-shaped arch structure 1, and a lining layer structure 9 at the inner circle and the bottom of the arc-shaped arch structure 1. As shown in Figure 1 、 Figure 2 and Figure 3 The special-shaped beam body 4 includes a plurality of inclined columns 10 arranged in the direction of the shed hole excavation, and a special-shaped joist 11 is installed at the top of the inclined column 10, and a bearing platform beam 12 is installed at the bottom. The special-shaped joist 11 is connected to one side of the arc-shaped arch structure 1 and the lining layer structure 9. As shown in Figure 1 The special-shaped beam body 4 further includes a plurality of transverse connecting beams 13 arranged in the direction of the shed hole excavation, and the bearing platform beam 12 is connected to the lining layer structure 9 through a plurality of transverse connecting beams 13 in the main hole structure.

[0056] In addition, the top of the special-shaped beam body 4 is provided with a plurality of transverse steel pipe piles 6 inclinedly punched into the slope body 2. Specifically, as shown in Figure 2 The special-shaped joist 11 is provided with a crown beam 14 above the main hole structure, and the crown beam 14 is located on the high mountain side of the center line of the main hole structure section, and the crown beam 14 is connected to one end of the transverse steel pipe pile 6.

[0057] As shown in Figure 2 The transverse steel pipe pile 6 is punched into the slope body 2, and the transverse steel pipe pile 6 is connected to the top of the special-shaped beam body 4 to form an anchoring unit, and the main hole structure is anchored on the upper side in the transverse direction through the anchoring unit. As shown in Figure 1 、 Figure 3 and Figure 4 A plurality of longitudinal pipes 3 form a longitudinal pipe shed 7, and the longitudinal pipe shed 7 forms a longitudinal bearing unit in cooperation with the relay wall 5, and the lower side of the main hole structure is supported through the longitudinal bearing unit when the rock mass excavation constraint is lost.

[0058] Further, as a preferred technical solution of the embodiment, as shown in Figure 4 and Figure 6 In this embodiment, the relay wall 5 is a wall structure with a right-angled trapezoidal cross section, one side of the relay wall 5 extends into the main hole structure, and the other side is embedded with the slope body 2.

[0059] The mechanical principle of the relay type underground excavation shed hole structure system is as follows:

[0060] The transverse steel pipe pile 6 is driven into the slope body 2 before the main hole structure construction, the end of the transverse steel pipe pile 6 is connected with the corbel 14 to form an anchoring unit, and the transverse "upper anchoring" is realized. In order to avoid the deformation of the pipe shed caused by the loss of the end constraint of the longitudinal pipe shed 7 during the excavation of the main hole structure, a plurality of relay walls 5 are arranged, and the relay wall 5 cooperates with the longitudinal pipe shed 7 to form a stable longitudinal bearing unit, and the "lower support" is realized.

[0061] After the excavation of the main hole structure, the soil at the slope toe is excavated, and the upper soil loses the support constraint and tends to slide obliquely downward, thereby generating a sliding force. The sliding force deducts the friction force on the sliding surface to form a residual sliding force. The residual sliding force is first borne by the anchoring unit, and the remaining part is applied to the bearing unit. The mechanical principle is shown in Figure 5 .

[0062] Due to the bearing unit formed by the transverse steel pipe pile 6, the relay wall 5 and the longitudinal pipe shed 7, the two bear all the residual sliding force, block the sliding tendency and displacement of the slope soil, and effectively isolate and block the disturbance caused by the shed hole excavation, thereby ensuring the safety and stability of the mountain and the shed hole.

[0063] Based on the above-mentioned relay type excavation shed hole structure system, the embodiment further provides a construction method of the relay type excavation shed hole structure system. The construction method comprises the following steps:

[0064] Step 1: Excavate the mountain in a small range, clear the operation platform, and drive the transverse steel pipe pile 6 into the mountain of the slope body 2. The end of the transverse steel pipe pile 6 is poured together with the corbel 14;

[0065] Step 2: Further excavate the mountain in a small range, and construct the pile cap beam 12, the inclined column 10 and the special-shaped joist 11;

[0066] Step 3: Determine the spacing and quantity of the relay wall 5 according to the geological conditions and the length of the shed hole;

[0067] Step 4: Determine the position of the relay wall 5 based on the spacing and quantity of the relay wall 5, mill and excavate the relay wall 5, and reserve a guide pipe at a suitable position of the relay wall 5 during the pouring process. The top of the relay wall 5 is consistent with the surface slope rate of the mountain;

[0068] Step 5: Drive the longitudinal pipe shed 7 from the position of the sleeve arch 8 to the relay wall 5, and the pipe shed passes through the relay wall 5;

[0069] Step 6: Excavate the main hole below the pipe shed and construct the lining layer structure 9;

[0070] Step 7: When the main hole structure is excavated to the relay wall 5, the part of the relay wall 5 in the main hole is removed by milling and excavating according to the tunnel contour, and the longitudinal pipe shed 7 is further driven from the reserved guide sleeve 15 of the relay wall 5 to the next relay wall 5;

[0071] Step 8, continue to excavate the main hole under the pipe shed; cycle the above steps until the main hole is through; when setting the longitudinal pipe shed 7, the upper angle is 1-3°, so that the whole longitudinal pipe 3 forms an arch shape.

[0072] Further, as shown in Figure 5 Step 3, the spacing of the relay wall 5 is determined as follows:

[0073] Step 3.1, calculate the residual sliding force of the slope:

[0074]

[0075]

[0076]

[0077] In the formula, , , is the residual sliding force of each part of the slope, where represents the first section of the slope body 2, represents the middle section of the slope body 2, represents the tail end of the slope body 2 close to the main hole structure; is the safety factor, generally taken as 1.3; , , is the weight of the potential sliding soil of each part of the slope; , , is the angle between the potential sliding soil of each part of the slope and the horizontal plane; , , is the internal friction angle of each part of the slope; , , is the cohesion of the rock-soil body of each part of the slope; , , is the length of the potential sliding soil of each part of the slope; is Figure 5 the load transfer coefficient between the corresponding slope body of the load transfer coefficient between the corresponding slope body of is the calculation method is:

[0078] .

[0079] Step 3.2, calculate the remaining sliding force that the load-bearing unit formed by the relay wall 5 and the longitudinal pipe shed 7 needs to bear:

[0080]

[0081] In the formula, is the remaining sliding force that the load-bearing unit needs to bear; is the distribution coefficient, which is 0-1.

[0082] Simplify the load-bearing unit formed by the relay wall 5 and the longitudinal pipe shed 7 as a single-span statically indeterminate beam with fixed connections at both ends, and calculate the limit deflection of a single longitudinal pipe 3 under the action of the remaining sliding force:

[0083]

[0084]

[0085] In the formula, is the remaining sliding force that a single longitudinal pipe 3 bears; is the layout spacing of the longitudinal pipes 3 of the longitudinal pipe shed 7; is the layout range of the longitudinal pipe shed 7; is the mid-span deflection of the longitudinal pipe shed 7; is the elastic modulus of the longitudinal pipe shed 7; is the cross-sectional moment of inertia of the longitudinal pipe shed 7 and the grouting body.

[0086] The calculation formula of the mid-span deflection of the longitudinal pipe shed 7 is as follows:

[0087]

[0088] In the formula, is the length of the longitudinal pipe 3 between the relay walls 5.

[0089] The calculation formula of the cross-sectional moment of inertia of the longitudinal pipe shed 7 and the grouting body is as follows:

[0090]

[0091] In the formula, is the diameter of a single longitudinal pipe 3.

[0092] Step 3.3, calculate the maximum tensile stress of a single longitudinal pipe 3 under the action of the remaining sliding force:

[0093]

[0094] In the formula, is the maximum tensile stress that a single longitudinal pipe 3 bears;

[0095] The maximum tensile stress should be less than the allowable stress of the steel pipe, and the safety factor is 1.5, and the allowable stress of the steel pipe is:

[0096] .

[0097] Step 3.4, based on the limit disturbance calculation of a single longitudinal pipe 3 and the maximum tensile stress of a single longitudinal pipe 3, the length of the pipe shed under the limit disturbance and allowable stress conditions of a single longitudinal pipe 3 is calculated respectively 、 ;

[0098]

[0099]

[0100] Step 3.5, the length of a single longitudinal pipe 3 should be taken as the smaller one of 、 ; the length of a single longitudinal pipe 3 is the spacing of the relay wall 5.

[0101] To verify the actual effect of the relay type underground shed structure system, the following actual engineering verification is carried out:

[0102] Taking a certain slope engineering as an example, the weight of the potential sliding soil body of each part of the slope = 1495 kN, = 2392 kN, = 2725.5 kN, = 21 m, = 11.69 m, = 9.47 m, the cohesion = 38 kPa, the friction angle = 28°, the slope safety factor = 1.3.

[0103] 、 、 ;

[0104] The layout range of the longitudinal pipe shed is 9.5 m, the layout spacing of the longitudinal pipe of the longitudinal pipe shed is 0.4 m, the diameter of a single longitudinal pipe is 0.108 m, and the elastic modulus of the longitudinal pipe shed = 95 × 10 4 MPa.

[0105] ① The relevant parameters are brought into the formula, and the residual sliding force F3 is calculated:

[0106]

[0107]

[0108] The remaining sliding force that the load-bearing unit formed by the relay wall and the longitudinal pipe shed needs to bear is calculated, and a distribution coefficient is taken here =0.8:

[0109]

[0110]

[0111]

[0112] The relevant parameters are brought in to calculate the remaining sliding force q that a single pipe shed bears:

[0113]

[0114] The relevant parameters are brought in to calculate the length of a single longitudinal pipe under the limit disturbance and allowable stress conditions 、 :

[0115]

[0116]

[0117] From the above calculation, it can be known that under the geological conditions, when the relay wall is set to be not more than 9.72m, the relay-type underground shed tunnel structure system can effectively isolate the disturbance of the shed tunnel excavation to the slope body, and ensure the stability of the shed tunnel and the mountain body during the tunnel construction process.

[0118] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A construction method of a relay-type underground excavation shed structure system, the construction method being based on a relay-type underground excavation shed structure, characterized by: The relay type underground excavation shed tunnel structure system comprises a main tunnel structure, and the main tunnel structure adopts the following structure in the slope body excavation section: The main tunnel structure comprises a group of circular arc arch body structures, the circular arc arch body structures are arranged at intervals, the circular arc arch body structures are connected through a plurality of longitudinal pipes on the side close to the slope body and connected through a special-shaped beam body on the other side; a plurality of relay walls are arranged at intervals on the side close to the slope body of the circular arc arch body structures, and the longitudinal pipe shed penetrates the relay walls; a plurality of inclined steel pipe piles are installed on the top of the special-shaped beam body and inclined into the slope body; The inclined steel pipe piles are punched into the slope body, the inclined steel pipe piles are connected with the top of the special-shaped beam body to form an anchoring unit, and the main tunnel structure is anchored on the upper side in the transverse direction through the anchoring unit; a plurality of longitudinal pipes form a longitudinal pipe shed, and the longitudinal pipe shed forms a longitudinal bearing unit in cooperation with the relay walls; and the lower side of the main tunnel structure is supported when the rock mass loses the constraint during excavation through the longitudinal bearing unit. The circular arc arch body structure comprises a sleeve arch located at the outer circle of the circular arc arch body structure and a lining layer structure located at the inner circle and the bottom of the circular arc arch body structure. The construction method of the relay type underground excavation shed tunnel structure system comprises the following steps: Step 1, a small range of mountain is excavated, a working platform is cleared, a horizontal steel pipe pile is punched into the mountain of the slope body, and the horizontal steel pipe pile is poured together with the corbel; Step 2, the mountain is further excavated in a small range, a bearing beam, an inclined column and a special-shaped supporting beam are constructed; Step 3, the interval and quantity of the relay walls are determined according to the geological conditions and the length of the shed tunnel; Step 4, the positions of the relay walls are determined based on the interval and quantity of the relay walls, the relay walls are milled and poured after excavation, the guide pipes are reserved at appropriate positions of the relay walls during the pouring process, and the top of the relay wall is consistent with the surface slope rate of the mountain; Step 5, the longitudinal pipe shed is punched into the relay wall from the position of the sleeve arch, and the pipe shed penetrates the relay wall; Step 6, the main tunnel is excavated below the pipe shed, and the lining layer structure is constructed; Step 7, when the main tunnel structure is excavated to the relay wall, the part of the relay wall in the main tunnel is removed by milling according to the tunnel contour, and the longitudinal pipe shed is punched into the next relay wall from the reserved guide sleeve pipe of the relay wall; Step 8, the main tunnel is continuously excavated below the pipe shed; the above steps are repeated until the main tunnel is connected; when the longitudinal pipe shed is punched, the upward angle thereof is 1-3°, so that the plurality of longitudinal pipes form an arch shape as a whole.

2. The construction method of the relay subsurface tunnel structure system according to claim 1, characterized in that: The relay wall is a wall structure with a straight-angle trapezoidal cross section, one side of which extends into the main tunnel structure, and the other side is embedded with the slope body.

3. The construction method of the relay subsurface tunnel structure system according to claim 2, characterized in that: The special-shaped beam body comprises a plurality of inclined columns arranged at intervals in the shed tunnel excavation direction, the top of the inclined column is provided with a special-shaped supporting beam, and the bottom of the inclined column is provided with a bearing beam; the special-shaped supporting beam is connected to one side of the circular arc arch body structure and the lining layer structure; the special-shaped beam body further comprises a plurality of transverse connecting beams arranged at intervals in the shed tunnel excavation direction, and the bearing beam is connected to the lining layer structure in the main tunnel structure through the plurality of transverse connecting beams.

4. The construction method of the relay subsurface tunnel structure system according to claim 3, characterized in that: The special-shaped supporting beam is provided with a corbel installed on the oblique upper side of the main tunnel structure, the corbel is located on the high mountain side of the center line of the main tunnel structure cross section, and one end of the corbel is connected with the horizontal steel pipe pile.

5. The construction method of the relay subsurface tunnel structure system according to claim 1, characterized in that: In step 3, the interval of the relay wall is determined as follows: Step 3.1, calculate the residual sliding force of the slope: ； ； ； wherein, , , is the residual downslope force of each part of the slope, wherein represents the first section of the slope body, represents the middle section of the slope body, represents the end section of the slope body close to the main hole structure; is the safety factor; , , is the weight of the potential downslope soil of each part of the slope; , , is the angle between the potential downslope soil of each part of the slope and the horizontal plane; , , is the internal friction angle of each part of the slope; , , is the cohesion of the rock-soil body of each part of the slope; , , is the length of the potential downslope soil of each part of the slope; , is the load transfer coefficient between the slopes ; Step 3.2, calculate the residual sliding force that the load-bearing unit formed by the relay wall and the longitudinal pipe shed needs to bear: ； wherein Fres the remaining glide force to be taken up by the carrying unit; is the distribution coefficient; Simplify the load-bearing unit formed by the relay wall and the longitudinal pipe shed into a single-span hyperstatic beam with fixed connections at both ends, and calculate the ultimate disturbance of a single longitudinal pipe under the action of the residual sliding force: ； ； wherein is the residual downforce borne by a single longitudinal tube; is the longitudinal tube layout spacing of the longitudinal tube shed; is the layout range of the longitudinal tube shed; is the midspan deflection of the longitudinal tube shed; is the length of the longitudinal tube between the intermediate walls; is the modulus of elasticity of the longitudinal tube shed; is the cross-sectional moment of inertia of the longitudinal tube shed and the grout body; is the diameter of a single longitudinal tube; Step 3.3, calculate the maximum tensile stress of a single longitudinal pipe under the action of the residual sliding force: ； wherein is the maximum tensile stress of the single longitudinal tube; Step 3.4, calculate the length of the pipe shed under the condition of the limit disturbance and allowable stress of single longitudinal pipe respectively based on the limit disturbance calculation of single longitudinal pipe and the maximum tensile stress of single longitudinal pipe , ; ； ； Step 3.5, length of single longitudinal tube Should take , The smaller of the two; length of single longitudinal tube Is the pitch of the relay wall.

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