JP7090515B2 - Invert construction method in tunnel - Google Patents

Description

The present invention relates to an invert construction method in a tunnel for installing an invert in the bottom ground of a new or existing tunnel.

When constructing a mountain tunnel or the like, if the bottom ground contains poor geological parts such as large earth pressure or water pressure, an invert is installed on the bottom ground for reinforcement. In addition, if the geology around the tunnel is poor in an existing tunnel without an invert, the structure of the tunnel may become unstable, such as the pavement of the tunnel being lifted or the lining side wall of the tunnel being cracked. In order to stabilize the structure of the tunnel, additional inverts are installed on the bottom ground.

In order to install the invert on the bottom ground of such a new or existing tunnel, various invert construction methods such as construction with cast-in-place concrete and construction with precast concrete have been conventionally implemented.

FIG. 4A shows the construction using cast-in-place concrete. In this construction, the following construction procedure is generally adopted.
(1) The invert installation portion P is excavated, and after the excavation, the formwork is assembled into a predetermined shape and the concrete C is placed.
(2) Curing is performed until the concrete C placed in the invert installation portion P reaches the required strength.
(3) When the concrete C of the invert installation portion P is solidified and develops the required strength, the formwork is disassembled, the earth and sand are backfilled on the concrete C, and a temporary road is formed on the concrete C.
This kind of invert construction method is disclosed in Patent Document 1 and the like.

FIG. 4 (b) shows the construction using precast concrete. In this construction, the following construction procedure is generally adopted.
(1) The invert installation part P is excavated, and after the excavation, the precast concrete PC manufactured at the factory is carried in and installed at a predetermined position of the invert installation part P by using a crane or the like.
(2) Assemble the formwork to fill the gap between the precast concrete PC of the invert installation part P and the ground below it, and after assembling this formwork, put non-shrink mortar as the backfill material in the gap. Fill.
(3) When the non-shrink mortar solidifies and reaches the required strength, the formwork is dismantled, the earth and sand are backfilled on the precast concrete PC, and a temporary road is formed on the upper part.
This kind of invert construction method is disclosed in Patent Document 2 and the like.

Japanese Unexamined Patent Publication No. 2000-64800 Japanese Unexamined Patent Publication No. 10-221886

However, the above-mentioned conventional invert construction method has the following problems.
(1) Construction with cast-in-place concrete becomes a problem especially when installing an invert in an existing tunnel. In the case of this construction, it is necessary to assemble the formwork in the invert installation part in the tunnel, so the work efficiency is low, and until the concrete placed in the invert installation part reaches the required strength, it will be in the invert installation part. The earth and sand cannot be backfilled, and the construction period is inevitably long. Therefore, in order to install an invert in the tunnel in service by construction with cast-in-place concrete, it is necessary to regulate the lane in the tunnel for a long period of time. During the construction period, there is a large social impact such as traffic congestion due to traffic restrictions, so it is difficult to respond to the request to shorten the number of regulation days.
(2) In the construction with precast concrete, the weight of one piece of precast concrete is very heavy, and the size of the crane that can be used in the tunnel is limited. In addition, the number of precast concrete divisions at the invert installation section increases. If the number of precast concrete divisions increases, the transportation cost from the manufacturing plant to the construction site will increase, and the process (labor) for installing the precast concrete will increase, causing construction delays and the schedule for lifting lane restrictions. Affects.

The present invention solves such a conventional problem, and in this kind of invert construction method, after installing an invert in the invert installation portion, the earth and sand can be backfilled in the invert installation portion at an early stage, and the inside of the tunnel can be backfilled. By shortening the period of road lane regulation (traffic regulation), reducing the weight of the invert (piece) installed in the invert installation part, and increasing the size of the invert, the cost required for transportation is reduced. The purpose is to make it easier to install the invert and shorten the man-hours and processes for installing the invert.

In order to achieve the above object, the present invention
In the invert construction method in the tunnel where the invert is installed in the bottom ground of the tunnel
An invert installation part was excavated in the ground at the bottom of the tunnel.
After the excavation of the invert installation portion is completed, only the steel shell of the synthetic segment having a synthetic structure of a steel shell having a concrete injection port and concrete injected into the steel shell from the concrete injection port in the invert installation portion. And backfill the invert installation part,
After backfilling the invert installation portion, concrete was injected and filled into the steel shell of the invert installation portion through the concrete injection port to complete the synthetic segment, and the steel shell and the inside of the steel shell were filled. With both concrete, deformation of the ground around the tunnel, resistance to external force,
The gist is that.
Then, when this invert construction method is carried out in the tunnel, the bottom ground of the tunnel is divided into two or three in the tunnel width direction, and one side of the two divisions in the tunnel width direction or a part of the three divisions. Excavation of the invert installation part, installation of only the steel shell of the synthetic segment, backfilling of the invert installation part, and injection and filling of concrete into the inside of the steel shell are performed in sequence, and one side or 3 is divided into two in the tunnel width direction. After installing the invert in a part of the division, the same construction is sequentially performed on one side of the two divisions or the rest of the three divisions in the tunnel width direction to install the invert.
In this case, the steel shell can bear only the overburden pressure acting on the synthetic segment buried in the invert installation part and the traffic load when the vehicle passes over the ground where the invert installation part is backfilled. In addition, increase the strength and strength of the steel shell.
In addition, this invert construction method is embodied as follows.
(1) When a six-sided steel shell is used for the steel shell and the steel shell is installed in the invert installation portion, the steel shell is installed in the invert installation portion via a quick-hardening mortar pack, and the steel shell and the steel are installed. Inject the backfill material between the shell and the ground. In this case, the quick-hardening mortar pack can be installed at an arbitrary position under the bottom surface of the steel shell (six-sided steel shell).
When a five-sided steel shell is used for the steel shell and the steel shell is installed in the invert installation portion, the steel shell is installed in the invert installation portion via a quick-hardening mortar pack, and concrete is placed inside the steel shell. At the time of casting, the concrete is injected and filled in the steel shell in contact with the ground immediately below the steel shell. In this case, the quick-hardening mortar pack is installed directly under the side wall of the steel shell (five-sided steel shell).
(2) Using a concrete injection hole drilled at one end of the steel shell and a concrete placing hose inserted into the inside of the steel shell from the concrete injection hole as a concrete injection port of the steel shell, the steel shell is installed in the invert installation portion. At that time, one end of the concrete casting hose is inserted from the concrete injection hole at one end of the steel shell to the other end in the steel shell, and when the invert installation portion is backfilled, the other end of the concrete casting hose is used. Is taken out above the backfilling completion height of the invert installation part, and after backfilling of the invert installation part, concrete is injected from the other end of the steel shell of the invert installation part through the concrete placing hose. While pulling out the concrete placing hose from the steel shell, it is injected to one end in the steel shell and filled in the entire steel shell.
Further, when the concrete injection hole drilled at one end of the steel shell and the sheath pipe connected to the concrete injection hole are used as the concrete injection port of the steel shell, when the steel shell is installed in the invert installation portion, the sheath pipe is used. One end is connected to the concrete injection hole at one end of the steel shell, and when the invert installation portion is backfilled, the other end of the sheath pipe is taken out above the backfill completion height of the invert installation portion, and the invert is performed. After backfilling the installation portion, a concrete casting hose is inserted through the sheath pipe from the concrete injection hole at one end of the steel shell of the invert installation portion to the other end in the steel shell, and the other end in the steel shell. You may inject concrete from the concrete, and while pulling out the concrete placing hose from the steel shell, inject it to one end of the steel shell and fill the entire inside of the steel shell.
(3) In the cases of (1) and (2) above, the steel shell is provided with an air vent together with the concrete inlet, and while the concrete is injected into the steel shell, the steel is provided by the air vent. Remove the air inside the shell.
In this case, the steel shell is installed in the invert installation portion by using a plurality of air vent holes drilled in the upper surface of the steel shell and a plurality of air through hoses connected to the air vent holes as the air vents of the steel shell. At the time, when one end of each of the air through hoses is connected to each of the air vent holes of the steel shell and each of the air through hoses is arranged outside the steel shell, when the invert installation portion is backfilled. , The other end of each air passage hose is taken out above the backfilling completion height of the invert installation part, and after backfilling of the invert installation part, while concrete is injected into the steel shell, each air passage hose is said. It is assumed that the air in the steel shell is evacuated.
Further, in this case, an air passage formed inside the steel shell as an air vent of the steel shell, an air vent hole formed by communicating with the ventilation passage at one end of the steel shell, and an air passage hose connected to the air vent hole. When the steel shell is installed in the invert installation portion, one end of the air through hose is connected to the air vent hole at the one end of the steel shell, and the air is backfilled when the invert installation portion is backfilled. The other end of the through hose is taken out above the backfilling completion height of the invert installation portion, and after backfilling of the invert installation portion, while concrete is injected into the steel shell, the inside of the steel shell is provided by the air through hose. It may be used to bleed the air from the hose.
Further, in this case, it is preferable to arrange filling sensing sensors for detecting the filling status of concrete at several places in the steel shell to check the filling status of concrete in the steel shell.

According to the invert construction method of the present invention, after the excavation of the invert installation portion is completed, only the steel shell of the synthetic segment is installed in the invert installation portion, the invert installation portion is backfilled, and after the invert installation portion is backfilled, the steel shell is backfilled. Through the concrete inlet provided in, concrete is injected and filled into the steel shell of the invert installation part to complete the synthetic segment, and both the steel shell and the concrete filled inside the steel shell deform the ground around the tunnel. Since it resists external force, it has the following special effects unique to the present invention.
(1) After installing only the steel shell as an invert in the invert installation part, it is possible to backfill the earth and sand in the invert installation part at an early stage. The process until the regulation (traffic regulation) is lifted can be shortened, and the period (days) of lane regulation can be significantly shortened as compared with the conventional case.
(2) The weight of the invert (piece) installed in the invert installation section can be reduced and the size of the invert can be increased. By increasing the size of the invert, the cost required for transportation can be reduced and the invert can be installed. It can be made easier and the man-hours and processes for installing the invert can be shortened.

The figure which shows the construction procedure of the invert construction method in the tunnel by one Embodiment of this invention ((1) excavates the invert installation part in the bottom ground of a tunnel, and after excavation of the invert installation part is completed, the synthetic segment in the invert installation part. The figure (2) showing the state in which only the steel shell is installed is after the steel shell is installed in the invert installation part, and the figure (3) showing the state in which the invert installation part is backfilled is after the invert installation part is backfilled. Figure showing the state of injecting concrete into the steel shell buried in the invert installation part of the tunnel) Enlarged view of the method of placing concrete in the steel shell buried in the invert installation part of the tunnel by the same construction method. The figure showing the installation method of the steel shell in the invert installation part and the treatment method between the steel shell and the ground contact surface in the invert installation part by the same construction method ((a) is a six-sided steel shell on the steel shell). The figure (b) showing the method of installing the steel shell and the treatment method between the steel shell and the ground contact surface when using the above is the method of installing the steel shell and the steel shell when the five-sided steel shell is used for the steel shell. Figure showing the treatment method between the ground ground planes) A diagram showing the conventional invert installation method ((a) is a diagram showing construction with cast-in-place concrete, and (b) is a diagram showing construction with precast concrete).

Next, a mode for carrying out the present invention will be described with reference to the drawings.

As shown in FIG. 1, the invert construction method in this tunnel is used to install the invert I in the bottom ground of the tunnel T, and in this construction method, the invert installation portion P is excavated in the bottom ground of the tunnel T. After the excavation of the invert installation portion P is completed, the steel shell of the synthetic segment 1 having a composite structure of the steel shell 10 having a concrete injection port and the concrete injected into the steel shell 10 from the concrete injection port in the invert installation portion P. Only 10 is installed to backfill the invert installation part P, and after backfilling the invert installation part P, concrete is injected and filled into the steel shell 10 of the invert installation part P through the concrete injection port to complete the synthetic segment 1. Both the steel shell 10 and the concrete filled inside the steel shell 10 were made to resist deformation and external force of the ground around the tunnel.

Then, in this invert construction method, when the tunnel T is carried out, the bottom ground of the tunnel T is divided into two or three in the tunnel width direction, and one side of the two divisions in the tunnel width direction or a part of the three divisions. Excavation of the invert installation part P, installation of only the steel shell 10 of the synthetic segment 1, backfilling of the invert installation part P, and injection filling of concrete into the inside of the steel shell 10 are performed in sequence, and one side is divided into two in the tunnel width direction. After installing the invert I on the side or a part of the three divisions, the same construction is performed sequentially on one side of the two divisions or on the other side of the three divisions in the tunnel width direction, and the invert I is installed.

Hereinafter, with reference to FIGS. 1, 2 and 3, the construction procedure for additionally installing the invert in the existing tunnel in service will be illustrated and the construction procedure will be specifically described.
In the existing tunnel T, the inner wall of the tunnel is covered with an arch-shaped structure A. In this construction, the invert 1 is installed on the bottom ground of the tunnel T and connected between the lower parts of the arch structure A. ..
Further, in this case, the bottom ground of the tunnel T is divided into two in the tunnel width direction for construction.

In this construction, first, as shown in FIG. 1 (1), a safety fence F is installed substantially in the center of the road R of the tunnel T. This ensures the passage of vehicles on R1 (on the right side in FIG. 1) on one side of the road. Subsequently, earth retaining piles S are driven into the safety fence F on the other side R2 side of the road at predetermined intervals in the direction of the tunnel axis. Then, the road other side R2 is excavated by an excavation machine (not shown) to form the invert installation portion P. Along with this excavation, a horizontal sheet pile (not shown) is installed on the earth retaining pile S to earth the earth on one side of the road R1. In addition to this excavation, a lining cradle B will be created at the bottom of the arch-shaped structure A on the inner wall of the tunnel. Then, every time the excavation length of the invert installation portion P advances by a predetermined distance (for example, 10 m to 20 m), the invert I is installed in the invert installation portion P.

As described above, the composite segment 1 having a composite structure of the steel shell 10 and the concrete 14 injected into the steel shell 10 is used for the invert I (see FIG. 3). In the case of this synthetic segment 1, a six-sided steel shell or a five-sided steel shell is used for the steel shell 10, and regardless of the case of the steel shell 10, the weight as the invert I is the conventional weight before the concrete 14 is injected. Compared to precast concrete, it is larger and lighter, so in this construction method, the size of the steel shell 10 is increased to the extent that it can be transported by truck or the like. Further, the steel shell 10 has a steel shell 10 against the overburden pressure acting on the synthetic segment 1 buried in the invert installation portion P and the traffic load when the vehicle passes over the ground where the invert installation portion P is backfilled. The strength and proof stress are increased by increasing the plate pressure on each surface of the steel shell 10 or by providing a vertical member (plate) or rib for reinforcement inside the steel shell 10 so that the burden can be borne only by the steel shell 10. When a vertical member (plate) for reinforcement is provided inside the steel shell 10, an opening for passing a hose 111, which will be described later, is provided in the vertical member (plate). Then, as shown in FIG. 2, the steel shell 10 is provided with a concrete injection port 11 on the upper surface together with an air vent port 12. In this case, as the concrete injection port 11, a concrete injection hole 110 drilled in one end of the steel shell 10 (the end of the upper surface plate on the inner wall side of the tunnel) and a concrete casting hose inserted into the steel shell 10 from the concrete injection hole 110. 111 and are used. Further, as the air bleeding port 12, a plurality of air bleeding holes 120 drilled in the upper surface (upper surface plate) of the steel shell 10 and a plurality of air through hoses 121 connected to these air bleeding holes 120 are used. Further, in the steel shell 10, a plurality of places for sensing the filling status of the concrete 14 at several places on the inner surface of the upper surface plate so that the filling status of the concrete 14 to be injected into the steel shell 10 can be confirmed. The filling detection sensor 13 is arranged.

In this installation work of Invert I, as shown in FIG. 1 (1), only the steel shell 10 of the synthetic segment 1 is installed. The concrete 14 to be filled in the steel shell 10 is post-filled. In this case, as shown in FIG. 3, the steel shell 10 is installed in the invert installation portion P via the quick-hardening mortar pack 21 in which the quick-hardening mortar is packaged. When a six-sided steel shell is used for the steel shell 10, as shown in FIG. 3A, the steel shell 10 is installed in the invert installation portion P via the quick-hardening mortar pack 21. In this case, the quick-hardening mortar pack 21 can be installed at an arbitrary position below the bottom surface of the steel shell 10. In this way, the backfill material 22 is injected between the steel shell 10 and the ground beneath the steel shell 10. When a five-sided steel shell is used for the steel shell 10, the steel shell 10 is installed in the invert installation portion P via the quick-hardening mortar pack 21 as shown in FIG. 3 (b). In this case, the quick-hardening mortar pack 21 is installed directly below the side wall portion of the steel shell 10. When the concrete 14 is placed inside the steel shell 10 in this way, the concrete 14 is injected and filled in the steel shell 10 in contact with the ground directly below the steel shell 10. This corrects the unevenness of the ground plane of the steel shell 10. Further, in this case, as shown in FIG. 1 (1), the invert installation portion of the road other side R2 of the tunnel T from the state where the length direction of the steel shell 10 is directed to the tunnel width direction. In P, it is installed and connected in parallel in the tunnel axial direction from one end to the other end in the tunnel axial direction. In addition, these steel shells 10 abut the end portion on the inner wall side of the tunnel with the lining pedestal B at the lower part of the arch-shaped structure A on the inner wall of the tunnel, and the arch-shaped structure A and the lining pedestal B pass through the lining pedestal B. Integrate.

After installing the steel shell 10 on the entire invert installation portion P on the other side of the road R2, as shown in FIG. 2, one end of the concrete placing hose 111 is inserted from the concrete injection hole 110 at one end of the steel shell 10 to the other end in the steel shell 10. Insert it to (the central end of the tunnel T), connect one end of each air passage hose 121 to each air vent hole 120 of the steel shell 10, and arrange each air passage hose 121 on the outside of the steel shell 10. Here, as shown in FIG. 1 (2), earth and sand are backfilled in the invert installation portion P from above the steel shell 10 without injecting the concrete 14 into each steel shell 10. Further, when backfilling the invert installation portion P, the other end (opening) of the concrete placing hose 111 is set to the other end (opening) of each air passage hose 121 before the earth and sand are backfilled in the invert installation portion P. At the same time, it is taken out above the backfilling completion height of the invert installation portion P of the tunnel T. After backfilling the invert installation part P, the upper surface is paved to form a temporary road, and as shown in FIG. 1 (3), the concrete placement taken out above the backfill completion height of the invert installation part P. The concrete 14 is injected from the other end of the steel shell 10 of the invert installation portion P through the hose 111, and while the concrete 14 is injected into the steel shell 10, the air in the steel shell 10 is evacuated by the air vent 12. , While gradually pulling out the concrete placing hose 111 from the inside of the steel shell 10, inject it to one end in the steel shell 10, and confirm the filling status of the concrete 14 in the steel shell 10 with each filling detection sensor 13 in the steel shell 10. While filling the entire inside of the steel shell 10. After the concrete is filled in the steel shell 10, each air through hose 121 for bleeding air may be pulled out from the steel shell 10 in the ground where the invert installation portion P is backfilled and taken out, and is left in the ground. You may. In the latter case, a grout material such as concrete, mortar, or epoxy resin is injected into each air passage hose 121 to fill the voids left inside each air passage hose 121. After backfilling the invert installation portion P in this way, the concrete 14 is cured in the steel shell 10 buried in the invert installation portion P. This eliminates the need for a special process (period) for curing the concrete 14 during the construction period. By doing so, after the steel shell 10 is installed in the invert installation portion P, the invert installation portion P can be immediately backfilled and a temporary road can be created on the invert installation portion P.

Excavation of such an invert installation portion P, installation of only the steel shell 10 of the synthetic segment 1 which is a post-filling type, backfilling of the invert installation portion P, injection filling of concrete 14 into the steel shell 10, and formation of a temporary road. Each step is repeated in units of predetermined distances (for example, 10 m to 20 m) at the bottom ground of R2 on the other side of the road of the tunnel T. Therefore, it is necessary to regulate the lane of the road other side R2 during the construction of the installation of the invert I on the road other side R2 in the tunnel T, but this construction is a predetermined distance (for example, 10 m to 20 m) on the road other side R2. Since it is done in units, it is possible to interrupt the installation work of Invert I in small steps and flexibly lift the lane regulation of R2 on the other side of the road in small steps, and shorten the lane regulation (period) as a whole. can.
Invert I (synthetic segment 1) is installed on the other side R2 of the road in the tunnel width direction in this way, and then construction is performed on one side R1 in the tunnel width direction in the same process to invert I (synthetic segment 1). To install. Similarly, in the road one side R1 in the tunnel T, the lane regulation of the road one side R1 is required during the construction of the installation of the invert I, but this construction is a predetermined distance (for example, for example) on the road one side R1. Since it is carried out in units of 10m to 20m), the installation work of Invert I can be interrupted in small steps, and the lane regulation of R1 on one side of the road can be flexibly lifted in small steps. Can be shortened.

As described above, according to this invert construction method, after the excavation of the invert installation portion P is completed, the steel shell 10 having the concrete injection port 110 and the steel shell 10 are injected into the steel shell 10 into the invert installation portion P. After the steel shell 10 of the filling type synthetic segment 1 having a composite structure with the concrete 14 is installed, the invert installation portion P is backfilled, and after the invert installation portion P is backfilled, the steel shell 10 is injected with concrete. Through the entrance 11, concrete 14 is injected and filled into the steel shell 10 of the invert installation portion P to complete the synthetic segment 1, and both the steel shell 10 and the steel 14 filled inside the steel shell 10 are used for the ground around the tunnel. After excavating the invert installation part P, if the steel shell 10 is installed in this invert installation part P, the invert installation part P can be backfilled at an early stage, and the invert installation part can be backfilled. After the backfilling of P, if the steel shell 10 buried in the invert installation portion P of the tunnel T is filled with the concrete 14 through the concrete injection port 11 of the steel shell 10, the synthetic segment 1 is completed, and in particular, the concrete 14 It is not necessary to secure the curing period as one step of the construction work, and the synthetic segment 1 as the invert I can be quickly installed in the invert installation unit P. Therefore, the process until the lane regulation (traffic regulation) of the road in the tunnel is lifted can be shortened, and the lane regulation period (days) can be significantly shortened as compared with the conventional case. Further, after excavating the invert installation portion P, only the steel shell 10 is installed as the invert piece in the invert installation portion P, so that the weight of the invert piece installed in the invert installation portion P can be reduced. By reducing the weight of the invert piece, the size of the invert piece can be increased, and by increasing the size of the invert piece, the cost required for transporting the invert piece (that is, the steel shell 10) can be reduced, and the invert piece (that is, the steel shell 10) can be transported. The man-hours and processes for installing the steel shell 10) can be shortened.

Then, in this invert construction method, when the tunnel T is carried out, the bottom ground of the tunnel T is divided into two in the tunnel width direction, the invert installation portion P is excavated from one side in the tunnel width direction, and the composite segment 1 is formed. After installing the invert I on one side in the tunnel width direction by sequentially installing only the steel shell 10, backfilling the invert installation portion P, and injecting and filling the concrete 14 into the inside of the steel shell 10, one side in the tunnel width direction. Since the invert I is installed on the other side by performing the same construction, the backfill of the excavated invert installation portion P on one side and each other side and the composite segment 1 as the invert I are performed on the bottom ground of the tunnel T. Installation can be done quickly and quickly. Therefore, the process until the lane regulation (traffic regulation) of the road in the tunnel is lifted can be shortened, and the lane regulation period (days) can be significantly shortened as compared with the conventional case.
For the implementation in the tunnel T, the bottom ground of the tunnel T is divided into three in the tunnel width direction, the invert installation portion P is excavated from a part in the tunnel width direction, and only the steel shell 10 of the synthetic segment 1 is installed. After backfilling the invert installation part P and injecting and filling the concrete 14 into the inside of the steel shell 10 and installing the invert I in a part in the tunnel width direction, the same construction is sequentially performed in the remaining part in the tunnel width direction. The same applies to the case where the tunnel I is installed (similar action and effect can be obtained).

Further, in this invert construction method, when a six-sided steel shell is used for the steel shell 10 and the steel shell 10 is installed in the invert installation portion P, the steel shell 10 is placed in the invert installation portion P via the quick-hardening mortar pack 21. Since the backfilling material 22 is injected between the steel shell 10 and the ground under the steel shell 10 after installation, the steel shell 10 is placed in the invert installation portion P and the ground contact surface of the steel shell 10 is treated (non-landing). Can be modified) and installed quickly. Further, when a five-sided steel shell is used for the steel shell 10 and the steel shell 10 is installed in the invert installation portion P, the steel shell 10 (the open surface of the five-sided steel shell faces the installation surface of the invert installation portion P). Is installed in the invert installation portion P via the quick-hardening mortar pack 21, and when the concrete 14 is placed inside the steel shell 10, the concrete 14 is injected in the steel shell 10 in contact with the ground directly under the steel shell 10. Since the steel shell 10 is filled, the steel shell 10 can be quickly installed in the invert installation portion P by treating the ground contact surface of the steel shell 10 (correcting the non-landing).

Further, in this invert construction method, a concrete injection hole 110 drilled at one end of the steel shell 10 and a concrete casting hose 111 inserted into the inside of the steel shell 10 from the concrete injection hole 110 are used as the concrete injection port 11 of the steel shell 10. When installing the steel shell 10 in the invert installation portion P, one end of the concrete placing hose 111 is inserted from the concrete injection hole 110 at one end of the steel shell 10 to the other end in the steel shell 10, and the invert installation portion P is backfilled. At this time, the other end of the concrete casting hose 111 is taken out above the backfilling completion height of the invert installation portion P, and after the invert installation portion P is backfilled, the steel of the invert installation portion P is passed through the concrete casting hose 111. The concrete 14 was injected from the other end of the shell 10, and while the concrete placing hose 111 was pulled out from the steel shell 10, it was injected to one end of the steel shell 10 to fill the entire inside of the steel shell 10. The synthetic segment 1 can be efficiently and quickly installed on the bottom ground of the T.
In this case, the air vent 12 is installed in the steel shell 10 together with the concrete inlet 11, and the air in the steel shell 10 is evacuated by the air vent 12 while the concrete 14 is injected into the steel shell 10. , The concrete 14 can be efficiently and quickly filled in the steel shell 10. Then, the steel shell 10 is inverted and installed by using a plurality of air bleeding holes 120 drilled in the upper surface of the steel shell 10 and a plurality of air through hoses 121 connected to each air bleeding hole 120 as the air bleeding port 12 of the steel husk 10. When installing in the part P, one end of each air through hose 121 is connected to each air vent hole 120 of the steel shell 10 and each air through hose 121 is arranged outside the steel shell 10 so that the invert installation part P can be installed. At the time of backfilling, the other end of each air passage hose 121 is taken out above the backfilling completion height of the invert installation portion P, and after backfilling of the invert installation portion P, while concrete is injected into the steel shell 10. Since the air in the steel shell 10 is evacuated by each air through hose 121, the air can be reliably evacuated from the inside of the steel shell 10 while the concrete is injected into the steel shell 10.
Further, in this case, filling sensing sensors 13 for detecting the filling status of the concrete 14 are arranged at several places in the steel shell 10, and each filling sensing sensor 13 determines the filling status of the concrete 14 in the steel shell 10. Since it is confirmed, the concrete 14 can be surely filled in the steel shell 10.

In this embodiment, as the concrete injection port 11 of the steel shell 10, a concrete injection hole 110 drilled at one end of the steel shell 10 and a concrete casting hose 111 inserted into the inside of the steel shell 10 from the concrete injection hole 110 are used. When installing the steel shell 10 in the invert installation portion P, one end of the concrete placing hose 111 is inserted from the concrete injection hole 110 at one end of the steel shell 10 to the other end in the steel shell 10, and the invert installation portion P is backfilled. At this time, the other end of the concrete casting hose 111 is taken out above the backfilling completion height of the invert installation portion P, and after the invert installation portion P is backfilled, the steel of the invert installation portion P is passed through the concrete casting hose 111. Concrete was injected from the other end of the shell 10, and while the concrete placing hose 111 was pulled out from the steel shell 10, it was injected to one end of the steel shell 10 to fill the entire inside of the steel shell 10. When the steel shell is installed in the invert installation part, one end of the pod is made of concrete at one end of the steel shell. Connect to the injection hole, and when backfilling the invert installation part, take out the other end of the sheath pipe above the backfilling completion height of the invert installation part, and after backfilling the invert installation part, put the concrete casting hose. Insert the steel from the concrete injection hole at one end of the steel shell of the invert installation part to the other end of the steel shell through the sheath pipe, inject concrete from the other end of the steel shell, and pull out the steel casting hose from the steel shell while steel. It may be injected up to one end in the shell and filled in the entire steel shell, and even in this case, the same effect as that of the above embodiment can be obtained.
Further, in this embodiment, as the air vent 12 of the steel shell 10, a plurality of air vent holes 120 drilled in the upper surface of the steel shell 10 and a plurality of air through hoses 121 connected to each air vent hole 120 are used. When the steel shell 10 is installed in the invert installation portion P, one end of each air passage hose 121 is connected to each air vent hole 120 of the steel shell 10 and each air passage hose 121 is arranged outside the steel shell 10. When backfilling the invert installation portion P, the other end of each air through hose 121 is taken out above the backfill completion height of the invert installation portion P, and after the invert installation portion P is backfilled, the inside of the steel shell 10 While the concrete was injected into the steel shell, the air in the steel shell 10 was evacuated by each air through hose 121. When a vertical member (plate) for reinforcement is provided, an air passage formed by making an air bleeding hole at the top of each vertical member, etc.) and an air bleeding drilled by communicating with a ventilation path at one end of the steel shell. Using an air through hose (neither mesh nor a hole in the middle of the hose, a general hose that allows air to flow) that connects to the hole and the air bleeding hole, attach the steel shell to the invert installation part. When installing, connect one end of the air through hose to the air vent hole at one end of the steel shell, and when backfilling the invert installation part, the other end of the air through hose is above the backfill completion height of the invert installation part. It may be taken out, and after the invert installation portion is backfilled, the air in the steel shell may be evacuated by an air through hose while the concrete is injected into the steel shell. It has an effect.
Further, in this embodiment, the case where the invert is installed in the bottom ground of the existing tunnel is illustrated, but it is needless to say that this invert construction method can be similarly applied to the bottom ground of the newly constructed tunnel. ..

T tunnel A arched structure R road R1 road one side R2 road other side F safety fence S earth retaining pile B lining cradle P invert installation part I invert 1 synthetic segment 10 steel shell 11 concrete injection port 110 concrete injection hole 111 Concrete casting hose 12 Air bleeding port 120 Air bleeding hole 121 Air bleeding hose 13 Filling detection sensor 14 Concrete 21 Fast-hardening mortar pack 22 Backfill material

Claims (10)

In the invert construction method in the tunnel where the invert is installed in the bottom ground of the tunnel
An invert installation part was excavated in the ground at the bottom of the tunnel.
After the excavation of the invert installation portion is completed, only the steel shell of the synthetic segment having a synthetic structure of a steel shell having a concrete injection port and concrete injected into the steel shell from the concrete injection port in the invert installation portion. And backfill the invert installation part,
After backfilling the invert installation portion, concrete was injected and filled into the steel shell of the invert installation portion through the concrete injection port to complete the synthetic segment, and the steel shell and the inside of the steel shell were filled. With both concrete, deformation of the ground around the tunnel, resistance to external force,
Invert construction method in a tunnel characterized by this. For implementation in the tunnel, the bottom ground of the tunnel is divided into two or three in the tunnel width direction, and the invert installation part is excavated from one side of the two divisions in the tunnel width direction or a part of the three divisions. Installation of only the steel shell, backfilling of the invert installation part, and injection and filling of concrete into the inside of the steel shell are performed in sequence, and the invert is installed on one side of the two divisions or a part of the three divisions in the tunnel width direction. The method of inverting in a tunnel according to claim 1, wherein the invert is installed by sequentially performing the same construction on one side of the two divisions or the rest of the three divisions in the tunnel width direction. When a six-sided steel shell is used for the steel shell and the steel shell is installed in the invert installation portion, the steel shell is installed in the invert installation portion via a quick-hardening mortar pack, and the steel shell and the bottom of the steel shell are installed. The invert construction method in a tunnel according to claim 1 or 2, wherein a backfill material is injected between the ground and the ground. When a five-sided steel shell is used for the steel shell and the steel shell is installed in the invert installation portion, the steel shell is installed in the invert installation portion via a quick-hardening mortar pack, and concrete is placed inside the steel shell. The invert construction method in a tunnel according to claim 1 or 2, wherein the concrete is injected and filled in the steel shell in contact with the ground directly below the steel shell. When installing the steel shell in the invert installation part using a concrete injection hole drilled at one end of the steel shell and a concrete placing hose inserted into the inside of the steel shell from the concrete injection hole as a concrete injection port of the steel shell. One end of the concrete placing hose is inserted from the concrete injection hole at one end of the steel shell to the other end in the steel shell, and the other end of the concrete placing hose is inverted when the invert installation portion is backfilled. After backfilling the invert installation part, concrete is poured from the other end of the steel shell of the invert installation part through the concrete placing hose, and the concrete is placed. The invert construction method in a tunnel according to any one of claims 1 to 4, wherein the concrete hose is pulled out from the steel shell, injected to one end in the steel shell, and filled in the entire inside of the steel shell. When the concrete injection hole drilled at one end of the steel shell and the sheath pipe connected to the concrete injection hole are used as the concrete injection port of the steel shell, and the one end of the sheath pipe is installed at the invert installation portion, the one end of the sheath pipe is used. It is connected to the concrete injection hole at one end of the steel shell, and when the invert installation portion is backfilled, the other end of the sheath pipe is taken out above the backfilling completion height of the invert installation portion, and the invert installation portion is taken out. After backfilling, a concrete casting hose is inserted through the sheath pipe from the concrete injection hole at one end of the steel shell of the invert installation portion to the other end of the steel shell, and concrete is inserted from the other end of the steel shell. The invert construction in the tunnel according to any one of claims 1 to 4, wherein the concrete casting hose is pulled out from the steel shell, poured to one end of the steel shell, and filled in the entire steel shell. Method. Any of claims 1 to 6 in which an air bleeding port is installed in the steel shell together with a concrete inlet, and air in the steel husk is evacuated by the air bleeding port while concrete is injected into the steel shell. Invert construction method in the tunnel described in. When installing the steel shell in the invert installation part by using a plurality of air bleeding holes drilled in the upper surface of the steel shell and a plurality of air through hoses connected to each of the air bleeding holes as the air bleeding port of the steel shell. One end of each of the air through hoses is connected to each of the air vent holes of the steel shell, and each of the air through hoses is arranged outside the steel shell. The other end of the air through hose is taken out above the backfilling completion height of the invert installation part, and after backfilling of the invert installation part, while concrete is injected into the steel shell, the steel is used by each of the air through hoses. The invert construction method in a tunnel according to claim 7, wherein the air in the shell is removed. As the air vent of the steel shell, an air passage formed inside the steel shell, an air vent hole formed at one end of the steel shell so as to communicate with the air passage, and an air through hose connected to the air vent hole are used. When the steel shell is installed in the invert installation portion, one end of the air passage hose is connected to the air vent hole at one end of the steel shell, and when the invert installation portion is backfilled, the other end of the air passage hose is connected. Is taken out above the backfilling completion height of the invert installation part, and after the backfilling of the invert installation part, the air in the steel shell is evacuated by the air through hose while the concrete is injected into the steel shell. Item 7. The invert construction method in the tunnel according to Item 7. The invert construction in the tunnel according to any one of claims 1 to 9, wherein sensors for detecting the concrete filling status are arranged at several places in the steel shell to confirm the concrete filling status in the steel shell. Method.

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