JP3863625B2 - Tunnel lining reinforcement method using mortar composite carbon fiber sheet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tunnel reinforcing method for a mountain tunnel, a subway shield tunnel, an underground station, an underground passage, and the like.
[0002]
[Prior art]
In such tunnels, the lining concrete deteriorates over time, and the proof strength decreases due to damage such as peeling of the lining and cracks, which may cause an unexpected disaster.
[0003]
Therefore, conventionally, when the lining concrete is deteriorated, a means for reinforcing the lining concrete has been adopted. As conventional reinforcing means,
(1) Adding concrete to the surface of lining concrete to increase the thickness.
(2) Method of installing secondary product concrete (precast RC) on the surface of lining concrete.
It has been known.
[0004]
[Problems to be solved by the invention]
However, in any of the above methods, since the placement of 20-30 cm thick concrete or secondary product concrete is made inside the tunnel, the inner cross-sectional area of the tunnel is greatly reduced, In addition to the problem that the effective cross section as a tunnel becomes narrow, there is a problem that full-line traffic stop or one-side traffic stop is necessary at the time of construction, and hot line construction is extremely difficult.
[0005]
Furthermore, there is a problem that the construction work such as a support work becomes large and the construction period required for the construction takes a long time.
[0006]
[Means for Solving the Problems]
In view of the above points, the present invention has been made with a problem that the reduction in the inner cross section of the tunnel is extremely small, and that the hot wire construction is possible and construction in a short construction period is possible. As a solution, a fast-strength cement mortar is applied to the lining surface of the tunnel, a carbon fiber sheet is pasted thereon, and bolts are placed on the lining concrete layer from above the carbon fiber sheet to thereby apply the carbon fiber sheet. The fast-strength cement mortar is fixed by impregnating an epoxy resin on the carbon fiber sheet fixed to the lining, solidifying the carbon fiber sheet, and then applying a fast-strength cement mortar from above. And a carbon fiber sheet are combined and integrated .
[0007]
In addition, an epoxy resin is applied to the lining surface of the tunnel, a carbon fiber sheet is pasted thereon, and the carbon fiber sheet is impregnated with an epoxy resin to form a first carbon fiber reinforced plastic sheet. Then, flow the early-strength cement mortar evenly over the release-treated plate, and put the carbon fiber sheet into contact with the carbon fiber sheet before it hardens. A second-layer carbon fiber-reinforced plastic sheet is formed by impregnation, and the second-layer carbon fiber-reinforced plastic sheet is stacked via an epoxy resin applied on the first-layer carbon fiber-reinforced plastic sheet. Before the epoxy resin of the second-layer carbon fiber sheet is hardened, bolts are placed on the lining concrete layer from above the composite plate, and the carbon fiber reinforced plus Secure the Kkushito the lining, characterized in that it comprises a step of finishing the surface of the carbon fiber sheet of the second layer in early strength cement mortar, mortar composite carbon fiber sheet according to the tunnel lining strengthening method, more in addition to the above SL each method, after construction of the carbon fiber sheet, can be made to be fixed and along the steel required width having a tunnel cross-sectional shape. In this case, the bolt for fixing the sheet may penetrate the steel material, and may be fixed to the lining concrete with the bolt together with the steel material.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to embodiments shown in the drawings.
FIG. 1 shows an example of subjecting a lining reinforcement 3 according to the present invention to the surface of a lining concrete 2 of a tunnel constructed in a natural ground 1, and FIG. 2 shows an embodiment of the invention according to claim 1. FIG. 1 is a partially enlarged view of the state where the lining reinforcement of FIG.
[0009]
The construction procedure for reinforcing the lining is as follows. First, a primer (adhesive) 4 is applied after removing the surface of the lining concrete 2 from the surface, and then an early-strength cement mortar 5 is applied. Application is performed, and before the cement mortar 5 is hardened, a carbon fiber sheet 6 is applied thereon.
[0010]
After the carbon fiber sheet 6 is attached, bolts 7 and 7 are installed, and the sheet 6 is fixed by the head 7a. The bolt 7 preferably has a diameter of about 6 mm and a length of about 40 mm, and is preferably made of stainless steel in order to prevent rusting. Further, the number of bolts 7 is set to about one per 1 m ² .
[0011]
As described above, the carbon fiber sheet 6 fixed by the bolts 7 is impregnated with a resin 8 such as an epoxy resin to solidify the carbon fiber sheet 6, and then the mortar 9 is applied thereon to finish.
[0012]
The final thickness by the above construction can be constructed with less than 8 mm.
[0013]
In addition, in claim 2, the early-strength cement mortar is uniformly flowed on a plate (not shown) subjected to the mold release treatment, and the carbon fiber sheet is brought into contact with and adhered before the early-strength cement mortar is hardened. A composite plate is formed by integrating a carbon fiber reinforced plastic sheet 10 obtained by impregnating an epoxy resin into a carbon fiber sheet and an early strength cement mortar, and the composite plate is covered as shown in FIG. Reinforcing work is performed by fixing the surface of the concrete 2 with bolts 7, injecting a grout cement mortar injection material 11 between the surface of the lining concrete 2 and the composite plate 10, and finishing the surface with mortar 9.
[0015]
5 and 6 show another embodiment of the present invention, in which an arch is formed to match the inner peripheral shape of the lining concrete 2 of the tunnel with a steel material having a width L of about 100 to 150 mm and a plate thickness of about 2 to 3 mm. In the case of the example of FIG. 2, the steel material 12 is brought into contact with the surface of the carbon fiber sheet 6 stuck as described above, and the width L of the steel material 12 is set. Bolts 7 are installed within the range, and then epoxy resin 8 and mortar 9 are applied in the same manner as in the above embodiment. The installation interval of the steel material 12 is 2 m as a standard. However, the dimensions and installation intervals of the steel material 12 are appropriately selected according to the deterioration state of the tunnel lining concrete 2 and the like. Note that the steel material 12 may be placed on the bolt 7 after the bolt 7 is driven.
[0016]
The above construction can be carried out on a simple movable lift, and does not require any large-scale equipment such as a support work or a formwork.
[0017]
When the strength test by the above-described lining reinforcement method was performed using the test piece 13 shown in FIG. 7, the result shown in FIG. 8 was obtained. That is, both ends of the test piece 13 having the carbon fiber sheet piece 15 fixed to the lower surface of the concrete 14 in each mode are supported by the fulcrums 16 and 16, and the load P is loaded at the center of the upper surface. In the case of reinforced concrete, the displacement at the center of the span is about 4 mm due to a load of less than 5 tons. The unreinforced reinforced concrete is about 5 tons. What was stopped with the bolt exceeded 8t, and what combined the carbon fiber sheet piece 15, the bolt, and the steel material reached 10t. As a result, it was found that the bending strength, shear strength, and toughness of the concrete are remarkably increased by carrying out the lining reinforcement method according to the present invention.
[0018]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
(1) By reinforcement with a carbon fiber sheet, it can be integrated with existing concrete and bend and shear can be reinforced at the same time.
(2) Since the surface is covered with a cement mortar layer, the structure is excellent in fire resistance, acid resistance, and fire resistance.
(3) High safety is ensured by bolts or bolts and steel.
(4) Since the thickness after the construction only needs to be increased by about 8 mm, the decrease in the inner cross section of the tunnel can be made extremely small.
(5) Construction in live lines is possible, and traffic obstruction can be reduced.
(6) The equipment for construction is simple and the construction period is remarkably short.
(7) The finished surface after construction can have the same color tone as the existing concrete.
[Brief description of the drawings]
FIG. 1 is a front view showing a tunnel as a construction example of the present invention.
FIG. 2 is an explanatory view of an embodiment of the reinforcing method according to claim 1 of the present invention, taken along an AA enlarged section of FIG.
FIG. 3 is a view corresponding to FIG. 2, showing an embodiment of a reinforcing method according to claim 2 of the present invention.
FIG. 4 is a view corresponding to FIG. 2 showing an embodiment of a reinforcing method according to claim 3 of the present invention.
FIG. 5 is a perspective view of a steel material when steel materials are used in combination (claims 4 and 5).
6 is a view corresponding to FIG. 2 and showing a state in which the steel material is reinforced together.
FIG. 7 is an explanatory diagram of a test piece for testing reinforcement strength according to the present invention.
FIG. 8 is a graph showing the test results.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ground mountain 2 Overlay concrete 3 Overlay reinforcement 4 Primer 5, 9 Cement mortar 6 Carbon fiber sheet 7 Bolt 8 Epoxy resin 10 Composite board 12 Steel material 13 Test piece 14 Concrete piece 15 Carbon fiber sheet piece 16 Support point

Claims (4)

Apply fast-strength cement mortar to the tunnel lining surface, and paste a carbon fiber sheet on it.
A bolt is placed on the lining concrete layer from above the carbon fiber sheet to fix the carbon fiber sheet to the lining,
The carbon fiber sheet is solidified by impregnating the epoxy resin on the carbon fiber sheet fixed by the bolt,
Furthermore, it includes a step of compositely integrating the early strength cement mortar and the carbon fiber sheet by applying the early strength cement mortar from above,
Tunnel lining reinforcement method using mortar composite carbon fiber sheet. The early-strength cement mortar is poured evenly on the release-treated plate, and the carbon fiber sheet is abutted and affixed before the early-strength cement mortar hardens, and this carbon fiber sheet is impregnated with an epoxy resin. A composite plate is formed by integrating the carbon fiber reinforced plastic sheet and the early strength cement mortar,
Bolts are placed on the lining concrete layer from above the composite board to fix the composite board to the lining, and grout cement mortar is injected into the gap between the composite board and the lining surface,
Characterized in that it includes a step of finishing the surface of the composite plate with a high-strength cement mortar,
Tunnel lining reinforcement method using mortar composite carbon fiber sheet. The tunnel lining reinforcement method by the mortar composite type | mold carbon fiber sheet of Claim 1 or 2 including the process of aligning and fixing the steel material of the required width which has the cross-sectional shape of a tunnel after construction of the said carbon fiber sheet. 4. The tunnel lining reinforcement method using a mortar composite carbon fiber sheet according to claim 3, wherein the bolt penetrates the steel material and is placed in a lining concrete layer.

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