KR20120017594A - Tunnel construction method using reinforcement wall - Google Patents

Abstract

PURPOSE: A tunnel construction method using a reinforcing wall is provided to increase stability by decreasing ground settlement, crown displacement, convergence displacement, face displacement and support stress. CONSTITUTION: A tunnel construction method using a reinforcing wall is as follows. A plurality of reinforcing walls(100) are formed on both sides of a tunnel excavated. The reinforcing wall supports the load of upper ground of the tunnel excavated. A loop of the tunnel is formed between the reinforcing walls. The loop of the tunnel is connected to the reinforcing wall. The inside of the tunnel is finished.

Description

Tunnel construction method using reinforcement wall {TUNNEL CONSTRUCTION METHOD WITH SUPPORT WALLS}

The present invention relates to a non-adhesive tunnel construction method (Modified-CAM), in particular, when the ground is shallow, such as low topi soil section, and the ground around the tunnel is stable and effective construction of the tunnel It is about how to.

Modified-CAM (hereinafter referred to as M-CAM) is a method that can safely construct tunnels without air delay or environmental complaints in low toe soil areas by applying the load transfer mechanism of Cellular Arch Method (hereinafter referred to as CAM).

The excavation method for the construction of structures in the low toe soil area is often applied to the open ground method after the upper ground has been grounded. However, when there is an urban center on the ground, it is inconvenient to control traffic for a long time. Therefore, conventionally, in order to construct the ground without attaching the upper ground, a method of completing a tunnel by applying a leg pile, an elephant foot, sidewall reinforcement, etc. in the tunnel shaft is generally used.

Conventional tunnel construction process of low topi soil section is a step of pressing the large diameter steel pipe 110 in the form of an arch (arch) before the tunnel excavation along the direction of the tunnel (X-axis direction), the paper holding material 108 or lattice paper holding ( It has been constructed including installing a rigid material) and forming an elephant foot, shotcrete placement, rock bolt construction step and leg pile construction, sidewall reinforcement step.

In order to reinforce the pit in accordance with the conventional method, it is necessary to additionally install an elephant foot and a leg pile to secure the bearing capacity and stability of settlement of the stiffeners 108, and the upper load during excavation. And in order to ensure the stability of the side wall portion load is required for the process of installing the side wall pile and the guide, such as the construction period is long, there is a problem that the displacement of the tunnel structure is large.

Therefore, the present invention is to remove the problems of the prior art described above to effectively construct a tunnel in a low topi soil section.

An object of the present invention is to increase stability in tunnel construction of low toffee soil sections by reducing surface settlement, shear deformation, pore displacement, membrane displacement, and support material stress, etc., compared to existing gang reinforcement methods. Another object of the present invention is to simplify the reinforcing process in the tunnel by constructing a reinforcement wall (vertical continuous wall) in advance, improving workability, shortening air, and reducing environmental complaints.

The object, according to the present invention, includes installing a plurality of reinforcing walls for supporting the upper ground load of the tunnel to be excavated to a predetermined depth on at least one side based on the tunnel excavation direction along the tunnel excavation direction This is achieved by a non-stick type tunnel construction method.

The installing of the reinforcing wall may include: generating a plurality of drilled holes having a predetermined depth in a direction crossing the tunnel drilling direction along the tunnel drilling direction; And placing concrete in each of the plurality of drilling holes; It may include, and may include the step of inserting a pre-made reinforcing wall into each of the plurality of drilling holes, omitting the step of placing concrete in the drilling hole.

The method may include forcibly hitting the reinforcing wall to the predetermined depth, omitting the step of forming the drilling hole and the pouring of concrete.

The present invention, the step of installing a gangjae for the reinforcement of the tunnel; It may further comprise the step of coupling the steel retainer and the reinforcing wall.

In addition, the step of coupling the stiffeners and the reinforcement wall, cutting the side portion of the reinforcement wall so that the side end portion of the stiffeners can be mounted; The cutting portion of the reinforcing wall and the side end portion of the steel retainer may include a step of using a fastener to join through which the object of the present invention is achieved.

According to the present invention described above, there are the following effects.

First, the tunnel can be safely constructed in low topi soil sections.

Second, the air can be shortened and the cost can be reduced compared to the conventional tunnel construction method.

1 is a cross-sectional view of a tunnel by a conventional gang reinforcement method,
Figure 2 is a cross-sectional view of the tunnel by the tunnel construction method of the present invention,
3 is a flow chart related to the step of installing the reinforcing wall according to the first embodiment of the present invention;
4 is a flow chart related to the step of installing the reinforcing wall according to the second embodiment of the present invention;
5 is a flow chart for the tunnel construction method of the present invention,
6A is a schematic cross-sectional view taken along line AA of FIG. 2;
6B is a schematic cross sectional view taken along line BB of FIG. 6A;
Figure 7 is a flow chart for the process of connecting the reinforcement wall and the stiffeners,
8 is a plan view of the reinforcing wall according to the present invention;
9 is a flowchart illustrating a comparison between the present invention and a conventional construction method;
10 is a graph comparing the effects of the present invention and the conventional construction method.

Looking at the construction method of the various tunnels to which the present invention can be applied as follows.

The method of forming a structure or creating a certain space in the basement is divided into a ground-breaking method of opening the ground according to the strength of the ground, the type of ground, and ground conditions, and a non-mounting (tunnel) method of not laying the ground.

In the ground-breaking method, earth-wall attachment is common, and pile-up, drilling and driving stages, road rehabilitation, protection of obstacles, excavation and installation of construction materials, construction and waterproofing of structures, backfilling and construction of construction materials Removing the package and recovering the package. The open type method is mainly used when the excavation depth is relatively shallow and there are no environmental problems such as traffic obstacles, obstacle interference, and noise and vibration, and it is mainly used in low toffee sections with shallow toffees or soils lacking firmness of the ground. It is a construction method.

The non-adhesive method includes a NATM method, a shield TBM method, a CAM method, a TRCM method, and the like. The present invention is a method of constructing an underground structure in which the NATM method is improved among the non-adhesive methods described above.

NATM method (New Austrain Tunneling Method) is to excavate the upper half section, cast the upper rock bolt and shotcrete, excavate the lower half section, cast the lower rockbolt and shotcrete, waterproof and lining concrete Including the step of pouring. The NATM method is effective when the ground itself is solid like rock, so that the ground itself can serve as a common treasure.

Specific embodiments of the present invention described above will be described in detail with reference to the drawings.

1 is a cross-sectional view (Y-axis direction) of a tunnel constructed according to a conventional gang reinforcement method.

2 is a cross-sectional view (Y-axis direction) of the tunnel constructed in accordance with the present invention.

In the non-open type tunnel construction method according to the present invention, as shown in Figure 2, the step of forming a reinforcement wall 100 on both sides of the tunnel to be excavated, to form a loop of the tunnel between the reinforcement wall 100 Step, connecting the loop of the tunnel and the reinforcing wall 100 and closing the interior of the tunnel.

Forming the reinforcing wall 100 on both sides of the tunnel, to support the upper ground load of the tunnel to be excavated to a predetermined depth on at least one side based on the tunnel excavation direction (X axis direction) of the tunnel It includes a step of installing a plurality of reinforcing wall 100 to.

Forming the loop of the tunnel, press the large diameter steel pipe 110 in the horizontal direction (X direction) in the tunnel working hole and grouting the inside of the large diameter steel pipe 110, excavated the upper half of the tunnel to secure the retaining material 108 )).

The connecting of the loop and the reinforcement wall 100 may include fixing and connecting the rigid support 108 of the loop with the reinforcement wall 100 to transfer the load acting on the loop to the reinforcement wall 100. Delivering.

Finishing the interior of the tunnel, after fixing and connecting the reinforcing wall 100 and the stiff retaining material 108 includes the step of placing the shotcrete inside the tunnel.

Therefore, in the present invention, the reinforcing wall 100 is pre-constructed and then fixedly connected to the rigid retainer 108 to allow the reinforcing wall 100 to receive the load on the tunnel.

The reinforcement wall 100 and the rigid retainer 108 are provided in contact with each other to receive a load from the rigid retainer 108. Of course, the reinforcement wall 100 and the stiffener 108 may be connected with a predetermined gap, and in this case, a separate connection member (not shown) is provided between the stiffening wall 100 and the stiffener 108. Can be.

The reinforcement wall 100 may be installed in various ways and in various shapes, and may form a vertical continuous wall (CPW) as shown in FIG. 2.

The present invention shown in Figure 2 includes the step of installing the reinforcing wall 100, unlike the conventional gangway reinforcement method, and the conventional gangway reinforcement method in that the installation of the side wall pile, leg pile, the elephant foot is not required It can be called an improved construction method. Of course, the step of installing the reinforcing wall 100 may be included in various construction methods.

Of course, the technical features of the present invention may not be limited to the above-described interpretation of the terms, and may be variously interpreted at the technical level of those skilled in the art.

In some cases, the present invention may proceed in parallel with the installation step of the reinforcing wall 100 and the construction step in the tunnel.

2 shows that the large diameter steel pipe 110 is arranged in two rows, but the number and arrangement of the large diameter steel pipe 110 are not limited and may be variously modified as necessary.

A first embodiment 300 of the installation of the reinforcement wall 100 is shown in FIG. 3.

In the non-open type tunnel construction method according to the first embodiment 300 of the present invention, forming a reinforcement wall 100 on both sides of the tunnel to be excavated, and forming a loop of the tunnel between the reinforcement wall 100. , Connecting the loop of the tunnel and the reinforcing wall 100 and closing the inside of the tunnel.

Here, the forming of the reinforcing wall 100 may include generating a drilling hole 310 to a predetermined depth, as shown in FIG. 3, placing a reinforcing bar in the drilling hole 310 and pouring concrete. It includes. In some cases, the reinforcing wall 100 may be provided by pouring only concrete without reinforcing the rebar.

Of course, in the step of generating the hole (310), obstacles (支 障 物), that is, underground burial, pipes, wires and various obstacles in order to check the progress and safely proceed with the basic digging of a predetermined depth (H1) can do.

In this case, since the drilling is carried out after the foundation digging, the concrete placement in the drilling hole 310 proceeds at a predetermined depth (H1) or less, and the reinforcing wall 100 has a predetermined depth (from a predetermined depth (H1) or less. Up to H1 + H2).

In addition, if there is no obstacle or the like, or not in the downtown area, the foundation digging may be omitted and the perforation and concrete pouring can be performed directly on the surface, the reinforcement wall 100 may be formed to a predetermined depth from the ground.

A guide casing (not shown) may be further provided to facilitate the drilling in generating the drilling hole 310.

Reinforce the reinforcing bars 331 before placing concrete in the drilling hole 310, and assembled into the drilling hole 310 by assembling the reinforcing bars 331 to fit the shape of the reinforcement wall 100 in advance in the ground You can also pour concrete. In some cases, only concrete can be poured without reinforcing bars.

In addition, after hardening is made after pouring concrete into the drilling hole 310, the upper portion of the drilling hole 310 can be finished. At this time, when rainwater or groundwater flows into the drilling hole 310, it may be a separate waterproof treatment because it may cause corrosion or defects in the tunnel later.

In the non-open type tunnel construction method according to the second embodiment of the present invention, forming a reinforcement wall 100 on both sides of the tunnel to be excavated, forming a loop of the tunnel between the reinforcement wall 100, the tunnel Connecting the loop and the reinforcing wall 100 and finishing the interior of the tunnel.

Wherein the step of forming the reinforcing wall 100 includes the step of preparing a punched hole as in the first embodiment, the step of placing concrete after reinforcing the reinforcing bars in the drilled hole or in some cases only concrete Can be omitted. Therefore, the construction period may be further shortened as compared with the first embodiment 300.

The forming of the reinforcing wall 410 according to the second embodiment may include separately manufacturing the reinforcing wall 410 with precast concrete, and drilling the reinforcing wall 410 made of the precast concrete. And inserting into the hole 310.

After inserting the reinforcing wall 410 into the drilling hole 310, concrete may be poured to remove the play between the drilling hole 310 and the reinforcing wall 410, to eliminate the play using mortar. It may be.

 Of course, the reinforcing wall 410 according to the second embodiment 400 is not limited to precast concrete, but may be formed of various materials that can withstand the load in the steel pipe and tunnel made of metal.

The drilling holes 310 of the first embodiment 300 and the second embodiment 400 may be provided in various ways, using a drill-shaped drill machine 320 of a screw, excavation in the drilling process And the earth and sand may be removed from the inside of the drilling hole 310.

The perforation hole 310 may be provided using a pile driver (not shown).

In the non-adhesive tunnel construction method according to the third embodiment (not shown) of the present invention, the step of forming the reinforcing wall may be omitted. That is, the step of drilling and the step of reinforcing the reinforcement or concrete is omitted, there may not be a drilling hole.

The reinforcing wall according to the third embodiment is manufactured separately and is installed to a predetermined depth by hitting or pressing in the ground at the position where the tunnel is to be formed. The reinforcing wall may be provided with various materials having rigidity of a predetermined value or more, such as concrete or metal.

Driving may be used to hit the reinforcement wall, and the reinforcement wall may be press-fitted through various means. The reinforcing wall may be smaller as the cross-sectional area goes downward to facilitate installation in the basement by hitting and pressing. In addition, the reinforcing wall may be manufactured in various shapes.

The reinforcement walls 100 and 410 according to the first, second, and third embodiments may be installed in a vertical direction (Z-axis direction) and a traveling direction (X-axis direction) of the tunnel. Of course, the traveling direction of the tunnel may not be parallel to the ground, and the angle formed between the axial direction of the reinforcing walls 100 and 410 and the traveling direction of the tunnel may not be 90 °.

The reinforcement walls 100 and 410 may be continuously formed at one side or both sides of the tunnel along the traveling direction of the tunnel. In some cases, the reinforcement walls 100 and 410 may be formed at predetermined intervals.

The drilling hole 310 may be provided to a point deeper than the bottom of the tunnel, in which case the reinforcing walls 100 and 410 are provided to a position deeper than the bottom of the tunnel.

5 illustrates a process (a → b → c → d) of constructing a tunnel using the reinforcement walls 100 installed in various ways according to the first, second and third embodiments. Of course, the construction method of the tunnel shown in FIG. 5 may be implemented by partially merging the construction of the step (a.b.c.d).

As shown in Figure 5 (a), the present invention after the construction of the reinforcement wall 100, the large diameter steel pipe 110 is pressed in the horizontal direction and grouting and excavating the upper half of the tunnel 150 step,

Installing the rigid retaining material 108 in the upper portion of the tunnel and fixing and connecting with the reinforcing wall 100,

Pour shotcrete in the tunnel,

Excavating the core 140 and the lower half 160 of the tunnel and finally lining 130 the interior of the tunnel with concrete.

As shown in FIG. 5, the excavation process of the tunnel is separated into the excavation of the upper half 150 and the excavation of the lower half 160 to safely proceed with the excavation when the ground is not solid, such as a low toffee soil section. 150) Leaving the core 140 during the excavation is to prevent the sediment inside the tunnel is pushed out by the earth pressure in the tunnel to ensure the stability of the membrane surface. Therefore, the core 140, the upper half and the lower half during the excavation is not necessary to separate the core, the upper half, and the lower half may not be excavated, on the contrary, if the ground is very fragile and the stability problem during the excavation, the upper half and The lower half can be further subdivided and the excavation can be applied.

6A is a cross-sectional view (Y-axis direction) of the reinforcing wall 100 and the connection portion 200 of the stiffener 130 shown in FIG. 2 on an A-A line.

6B is a longitudinal cross-sectional view (Z-axis direction) illustrating an enlarged view of the connecting portion 200 of the reinforcement wall 100 and the stiffener 130 shown in FIG. 6A with respect to the B-B line.

The reinforcing wall 100 is fixedly connected to the stiffeners 108 to receive the load received by the stiffeners 108.

6A and 6B have fastened the reinforcing wall 100 and the steel retainer 108 using a plurality of anchor bolts 105. The anchor bolt 105 may use a chemical anchor.

Of course, the connection portion 200 may be connected using various fasteners in addition to the anchor bolt 105.

7 illustrates a process of fastening the connection part 200 to the anchor bolt 105.

Looking at the connection process shown in Figure 7, the excavation of the upper half of the tunnel after the cutting part of the side of the reinforcing wall 100 in the tunnel portion of the mounting portion 201 can be mounted on both ends of the stiffeners 108 ), To install the anchor 105, and to fix the rigid retaining material 108 to the mounting portion 201 and to fix it with a bolt (108).

The mounting portion 201 may be provided in various ways. That is, the side surface of the reinforcement wall 100 may be partially cut inside the tunnel to be provided to the inside of the reinforcement wall 100. It may be provided to the outside of the wall (100).

Of course, by omitting the step of providing the mounting portion 201 to the reinforcing wall 100, both ends of the stiffeners 108 may not be mounted. In this case, a separate connecting member (not shown) is provided between the reinforcing wall 100 and the stiffening member 108 to eliminate the play and the reinforcing wall 100, the connecting member (not shown) and the stiffening member. 108 can be connected through a variety of fasteners.

8 is a view showing a plane in a horizontal direction (X axis direction) parallel to the traveling direction of the tunnel around the reinforcement wall 100 in the tunnel construction method according to the present invention.

According to FIG. 8, the reinforcing wall 100 forms a continuous pile wall made of reinforcing bars 101 and 102 and concrete, and a cross section of the reinforcing wall 100 is circular. In addition, the reinforcing wall 100 is provided in contact with each other.

Of course, the reinforcement wall 100 may be provided by pouring only concrete without using reinforcing bars, and the reinforcement wall 100 may be provided using various materials having strengths higher than a predetermined value.

In addition, the reinforcement wall 100 may be provided with a material that hardens after a predetermined time after pouring in addition to concrete.

The reinforcing wall 100 is not limited to the shape of the pillar may have a cross section of various forms. In addition, the reinforcement walls 100 may not be continuously arranged, and the interval therebetween may have a predetermined clearance as needed. The distance L1 between the center and the center of the reinforcing wall 100 may be variously modified depending on the case.

Figure 9 shows a comparison of the flow according to the present invention with a flow chart of the conventional gangster reinforcement method.

According to FIG. 9, compared to the conventional tunnel construction method, the leg pile, the elephant foot, the side wall pile, and the inverted process are eliminated, so that the cycle time can be reduced and the forward drilling can be performed collectively by the existing method. have.

As described above, in addition to the effect of shortening the air by eliminating some processes compared to the conventional tunnel construction method, it is possible to obtain a more stable tunnel construction by reducing displacement and support stress in the tunnel.

Non-adhesive tunnel construction method (M-CAM) according to the present invention will be described in detail in [Table 1], [Table 2] and [FIG. 10] by comparing the conventional gang reinforcement method. Of course, the following [Table 1], [Table 2] and [FIG. 10] is only one example for comparing the present invention and the conventional gangster reinforcement method, it may have various embodiments. For example, the specifications of the present invention and the conventional mine reinforcement method described in [Table 1] are not limited to those described in [Table 1].

Table 1 says the specifications in the construction method and the conventional reinforcement method of the present invention.

Table 2 compares the effects of the method of the present invention and the conventional reinforcement method.

10 is a graph showing the data of Table 2.

In [Table 1], excavation site refers to the excavation distance at the time of tunnel construction, and shotcrete is mainly used for primary lining for the purpose of hardening early. Cainvert refers to an invert that is temporarily installed in the upper half of the lower half after digging the upper half before digging the lower half.

When considering the table 1, the wall by the reinforcing member controls the displacement of the side when applying the method of the present invention, and compared to the existing tunnel construction method because the thickness of the shotcrete at the bottom of the tunnel is reduced by 150 mm compared to the existing gang reinforcement method. It shows a 60% reduction, and it is possible to omit the installation of the second half stiffeners and caverns.

In addition, as shown in the analysis results of [Fig. 10] and [Table 2], when the present invention method is applied, the surface and sediment settlements are reduced by about half, and the internal displacement is 2.06mm from 6.66mm outward. It was reduced by about 70%. In addition, the film displacement decreased by 80% from 11.06mm to 2.25mm and the shotcrete stress decreased by more than 40% from 7.67MPa to 5.92MPa. The groundwater inflow decreased from 1.04 m3 / min / km to 0.91 m3 / min / km, which showed superior tunnel reinforcement effect compared to the existing mine reinforcement method.

As described above, the present invention has an excellent effect compared to the conventional tunnel construction method.

The present invention is not limited to the above-described embodiments, and various modifications and embodiments of the present invention are apparent to those skilled in the art.

10: elephant foot 20: leg pile
40: Cainbert 50,120: Shotcrete
60,130: lining 100,410: reinforcement wall (vertical continuous wall)
101, 102, 331: rebar 105: anchor
200: reinforcement wall and the steel support portion 201: mounting portion
110: large diameter steel pipe 108: gangjibojae
140: core 150: upper half
160: lower half 300: first embodiment
310: drilled hole 320: drill machine
330: crane 340: concrete pouring machine
400: second embodiment 410: precast concrete
109: Bolt
h1: Digging depth h2: Drilling hole depth
L1: center distance of reinforcement

Claims (6)

In the non-open type tunnel construction method,
And installing a plurality of reinforcing walls for supporting the upper ground load of the tunnel to be excavated to a predetermined depth on at least one side of the tunnel excavation direction along the tunnel excavation direction. The method of claim 1,
Installing the reinforcing wall,
Generating a plurality of drilled holes having a predetermined depth in a direction crossing the tunnel drilling direction along the tunnel drilling direction; And
Placing concrete in each of the plurality of perforation holes; Non-removable tunnel construction method comprising a. The method of claim 1,
Installing the reinforcing wall,
Generating a plurality of drill holes having a predetermined depth in a direction crossing the tunnel excavation direction along the tunnel excavation direction; And
And a non-removable tunnel construction method comprising inserting the reinforcing wall into each of the plurality of drilling holes. The method of claim 1,
Installing the reinforcing wall,
The method of claim 1, further comprising the step of forcibly hitting the reinforcement wall to the predetermined depth to install. The method of claim 1,
Installing a stiffener for reinforcement of the tunnel;
The non-open type tunnel construction method further comprising the step of coupling the steel retaining material and the reinforcing wall. The method of claim 5,
Combining the steel retainer and the reinforcement wall,
Cutting a part of the side surface of the reinforcing wall so that the side end of the steel retainer can be mounted;
And the cutting portion of the reinforcing wall and the side end portion of the steel retaining member are coupled using a fastener.

Images