JP3904881B2 - Construction method of existing roadbed surface support - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing an existing roadbed surface support , and in particular, it is constructed with high accuracy while suppressing the occurrence of mortar outbreak, ground uplift and settlement of the existing roadbed surface support, and inside the existing roadbed surface support. It is related with the construction method of the existing roadbed surface support body which forms active space.
[0002]
[Problems of conventional technology]
As an example of a conventional existing roadbed surface support, as shown in FIG. 11, an existing roadbed surface support 30 is configured in the ground 5 below the existing roadbed surface 3 to construct a structure on the roadbed surface such as a railway bridge 4. It was constructed by the following process.
(1) A shaft is constructed at a predetermined interval in the ground 5 below the existing roadbed surface 3.
(2) After injecting the chemical solution 14 in the horizontal direction from one of the pair of vertical shafts toward the propulsion embedding portion of the tubular steel pipe 31, the tubular steel pipe 31 is constructed in a gate shape and made of tubular steel. Concrete 32 is placed in the pipe 31.
(3) Horizontal or diagonally below one of the vertical shafts so that the cylindrical steel pipe constructed in the gate shape does not sink even if the inner surface of the portal shape is excavated below the cylindrical steel pipe constructed in the portal shape. The soil is improved by a soil cement improved body or the like that can be formed by cement milk injected into the ground and the local soil, and a work space 34 is formed by excavating the gate-shaped inner surface.
(4) After the cast-in-place concrete pile 36 is constructed toward the lower ground 35 of the work space 34, the concrete 37 is placed in the work space, and the cylindrical steel pipe 31 and the cast-in-place concrete pile 36 are integrated. To do.
[0003]
In this construction example, although there is a merit that the ground is not loosened as a ground improvement method that allows horizontal construction, it is necessary to inject chemicals and improve the ground. It was necessary to construct so as not to loosen the ground while constructing the mold, so that the mortar would not erode and the ground would not rise, and the following points had to be dealt with carefully.
(1) Take measures to control the amount of subsidence on the existing roadbed surface.
(2) Take measures to confirm improved ground strength.
(3) Take measures that do not require a long construction period.
[0004]
[Problems to be solved by the invention]
The present invention is proposed in order to alleviate the necessity in view of the construction situation as in the above example, and the occurrence of mortar, ground uplift or subsidence of existing roadbed surface support caused by ground improvement Of the existing roadbed surface support that can form an active space such as a work space for constructing underground passages and incidental structures such as underpasses, etc. inside the gate-type support body. We provide construction methods .
[0005]
[Means for Solving the Problems]
The construction method of the existing roadbed surface support that is the invention according to claim 1 comprises a gate-type support horizontally embedded in the ground below the existing roadbed surface, and works on the lower end of the side wall of the gate-type support The process of forming a space, the process of press-fitting a plurality of ready-made piles in the vertical direction from the work space to the lower ground, filling the work space at the lower end of the side wall of the gate-type support body with concrete and the ready-made gate-type support body It consists of the process of integrating the piles and the process of forming an active space inside the gate-type support body, which suppresses the occurrence of mortar outbreak, ground uplift or subsidence of existing roadbed surface support caused by ground improvement. While being constructed with high precision, an effective active space is formed inside the portal support.
[0006]
The construction method of the existing roadbed surface support that is the invention according to claim 2 is the construction method according to claim 1 , wherein the work space formed in the gate-type support and the lower end of the side wall is in the form of a filled concrete cylinder. Work formed on the side wall and bottom end of the side wall of the gate-type support formed by embedding a tubular steel pipe made of filled concrete in the vertical direction from the ceiling and the ceiling of the gate-type support formed by embedding the steel pipe in the horizontal direction It is characterized by comprising space, and in addition to the above functions, it maintains a stable construction state while suppressing settlement.
[0007]
The construction method of the existing roadbed surface support that is the invention according to claim 3 is the construction method according to claim 1 or 2 , wherein the press-fitting of the prefabricated pile in the vertical direction toward the lower ground is formed at the lower end of the side wall. In addition to the above functions, the ready-made piles can be constructed in a stable state with subsidence. ing.
[0008]
The construction method of the existing roadbed surface support that is the invention according to claim 4 is the construction method according to any one of claims 1 to 3 , wherein the step of forming an active space inside the portal support is a filling It is characterized by excavating the internal ground of the portal support while measuring the amount of settlement at the ceiling of the portal support made of concrete tubular steel pipe. In addition to the above functions, the formation of active space is stable. We are constructing.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In the present embodiment, the existing roadbed surface support is basically configured in the ground below the existing roadbed surface, and in the existing roadbed surface support that supports the structure on the existing roadbed surface, the ground below the existing roadbed surface. It consists of a gate-type support buried in the inside, a plurality of ready-made piles arranged at the lower end of the side wall of the gate-type support, and an active space formed inside the gate-type support. As a form, it is formed by joining cylindrical steel pipes made of filled concrete that embed the portal support in the ground below the existing roadbed surface, and this filled concrete tubular steel pipe generates a horizontal force in the direction perpendicular to the cylindrical steel pipe axis. In addition to being able to transmit, it is characterized in that it is rigidly joined to the upper end portion of a prefabricated pile buried in the vertical direction of the ground at the lower end portion of the side wall of the portal support.
[0010]
Hereinafter, an embodiment of an existing roadbed surface support will be described in detail with reference to the drawings. In order to facilitate understanding, the same reference numerals as those in the conventional example are used for the same portions.
[0011]
FIG. 1 shows an embodiment in which an existing roadbed surface support is applied to a railway bridge, and only one side of the railway bridge is shown in cross section.
[0012]
In the figure, the existing roadbed surface support body 1 supports the bridge 4 for the track constructed on the existing roadbed surface 3 having a large span because it straddles the road 2 at both ends.
[0013]
The existing roadbed surface support 1 is disposed at the lower end 8 of the gate-type support 6 embedded in the ground 5 of the existing roadbed surface 3 and the side walls 7, 7 constituting the gate-type support 6. It is comprised from the active space 10 formed inside the some ready-made pile 9 and the gate-type support body 6. FIG.
[0014]
The gate-type support body 6 is composed of a ceiling portion 12 formed by connecting filled concrete tubular steel pipes 11 in the horizontal direction and side walls 7 and 7 formed by vertically stacking on both sides of the ceiling portion 12. ing. The filled concrete cylindrical steel pipes 11 arranged in the horizontal direction or stacked in the vertical direction are firmly coupled so as to be able to transmit a horizontal force and a vertical compressive force in a direction perpendicular to the cylindrical steel pipe axis. In addition, the holding force for the railway bridge 4 is reinforced by forming a gate shape.
[0015]
A plurality of ready-made piles 9 embedded in the vertical direction of the ground are respectively arranged at the lower ends 8 of the side walls 7, 7 formed on both sides of the gate-type support 6. The upper end of the ready-made pile 9 is integrated by rigid joining, and the gate-type support 6 is supported by the ready-made pile 9, thereby preventing the existing roadbed surface support 1 from sinking.
[0016]
The form of the filled concrete tubular steel pipe 11 can adopt various forms such as the form of a PC steel pipe pile and the filling of concrete after drilling only the tubular steel pipe. If the form which can establish the function which can transmit the horizontal force in the orthogonal direction of a steel pipe axis and the compressive force of a perpendicular direction is established, the portal support body 6 with which the existing roadbed surface support body 1 is comprised can be constructed | assembled.
[0017]
The gate-type support 6 is formed in a rigid state in which a plurality of ready-made piles 9 are rigidly joined to the lower end portions 8 of the side walls 7 and 7 formed on both sides, and settling is prevented. An active space 10 such as a work space for constructing an underground passage such as an underpass or an incidental structure can be formed inside the body 6.
[0018]
Thus, the existing road surface support 1 not only supports the bridge 4 for the track, but also forms an active space 10 such as an underground passage such as an underpass in the interior of the support for the track bridge 4 so There are many opportunities that can be used effectively by forming exchanges.
[0019]
As is clear from the detailed description based on the above embodiment, the existing roadbed surface support of the present embodiment , combined with support by a plurality of ready-made piles, eliminates the need for ground improvement work and eliminates the need for ground improvement work. In addition to suppressing dredging, ground uplift and settlement of the existing roadbed surface, construction can be performed with high accuracy, and an effective active space can be formed inside the portal support.
[0020]
Next, the construction method of the existing roadbed surface support according to the present invention will be described. The construction method of the existing roadbed surface support according to the present invention basically consists of a gate-type support horizontally embedded in the ground below the existing roadbed surface, and a work space is provided at the lower end of the side wall of the gate-type support. A step of forming, a step of press-fitting a plurality of ready-made piles in a vertical direction from the work space toward the lower ground, a concrete filling the work space at the lower end of the side wall of the gate-type support, and the gate-type support and the ready-made pile And the step of forming an active space inside the portal support, specifically, the working space formed at the portal support and the lower end of the side wall is made of a filled concrete cylinder. Formed on the side wall of the gate-type support body formed by embedding a cylindrical steel pipe in the vertical direction from the ceiling portion and the ceiling portion of the gate-type support body formed by embedding the steel pipe in the horizontal direction. Ready-made in the vertical direction, consisting of a working space or facing down to the ground The step of forming the active space inside the gate-type support body is carried out sequentially while adding the ready-made piles divided using the jack device arranged on the upper surface of the work space formed at the lower end of the side wall, It is characterized by excavating the internal ground of the portal support while measuring the amount of settlement at the ceiling of the portal support made of filled concrete tubular steel pipe.
[0021]
Below, the construction method of the existing roadbed surface support body by this invention is demonstrated in detail based on FIGS. 2-10 which shows embodiment.
[0022]
FIG. 2 is a cross-sectional view of the shaft constructed on both sides of the planned construction portion of the gate-type support before the gate-type support is constructed in the ground below the existing roadbed surface.
[0023]
In the present embodiment, the railway bridge 4 is constructed on the upper surface of the existing roadbed surface 3, and the left and right sides of the railway bridge 4 have a portal type on the existing roadbed surface 3 on both sides of the railway bridge 4. In order to carry out operations such as constructing a support body, a pair of vertical shafts 13 and 13 are constructed on the front and rear sides across the planned bridge portion of the gate-type support body.
[0024]
FIG. 3 is a cross-sectional view below the existing roadbed surface for constructing the portal support. In this process, when constructing the gate-type support, the chemical solution 14 is horizontally applied from each vertical shaft 13 to the planned part for constructing the gate-type support as a measure for water stoppage in the ground below the groundwater level during steel pipe propulsion. By injecting, the safety of steel pipe propulsion drilling is aimed at.
[0025]
The gate-type support 6 is composed of a ceiling portion 12 and side walls 7 and 7 constituting both sides thereof. In this embodiment, a concrete steel tubular steel pipe filled in the ground of a reinforced existing roadbed surface 5 is used. By embedding 11 in the horizontal direction, the portal support 6 is configured.
[0026]
The ceiling 12 of the portal support 6 is formed by embedding a filled concrete cylindrical steel pipe 11 in the horizontal direction and firmly bonding the horizontal force in the direction perpendicular to the cylindrical steel pipe axis so that they can be transmitted to each other. Has been. Similarly, the side wall 7 of the gate-type support 6 is configured so that a compressive force can be transmitted by vertically laminating a cylindrical steel pipe 11 made of filled concrete, but is positioned at the lower end portion 8 of the side wall 7. With respect to the individual cylindrical hollow steel pipes 15, 15, the work space 16 is configured without filling with concrete.
[0027]
It is possible to embed the cylindrical hollow steel pipe 15 by adopting a construction method different from the burying of the filled concrete cylindrical steel pipe 11, and in this embodiment, as shown in FIG. The cylindrical hollow steel pipe 15 is pulled by the traction devices 17 'and 17' along the stranded wires 17 and 17. A drilling device 18 is provided at the tip of the cylindrical hollow steel pipe 15, and exhibits the advantage of being able to construct the cylindrical hollow steel pipe 15 at high speed and with high accuracy.
[0028]
Therefore, the burying of the cylindrical hollow steel pipe 15 can be adopted also when the ceiling portion 12 and the side walls 7 and 7 in the above-mentioned gate-type support body 6 are configured, and as shown in FIG. Instead of embedding the concrete tubular steel pipe 11, a construction method of filling the concrete 19 after embedding the tubular hollow steel pipe 15 can also be carried out.
[0029]
In the construction method of the existing roadbed surface support according to the present invention, a process of press-fitting a plurality of ready-made piles after forming a work space at the lower end of the side wall of the gate-type support is employed. Construction is carried out as shown in FIG.
[0030]
FIG. 6 shows a process of constructing a ready-made pile from the work space formed at the lower end of the side wall of the portal support.
[0031]
In this process, the vertical ready-made pile 9 is press-fitted from the work space 16 formed in the two cylindrical hollow steel pipes 15 and 15 located at the lower end portion 8 of the side wall 7 toward the lower ground. The press-fitting of the ready-made pile 9 is performed sequentially by adding the divided straight pipes 21 while using the jack device 20 arranged on the upper surface of the work space 16, and the supporting force of the ready-made pile 9 is used in the press-fitting. Is measured.
[0032]
When the ready-made pile 9 is press-fitted to a predetermined depth, the gate-type support body and the ready-made pile are integrated, and these steps are shown in FIG.
[0033]
Fig.7 (a) is sectional drawing which shows the state with which the gate-type support body and the ready-made pile were integrated, FIG.7 (b) is an enlarged view in B part of Fig.7 (a), FIG.7 (c) ) Is an enlarged view of a portion C in FIG.
[0034]
Since the cylindrical hollow steel pipes 15 and 15 forming the work space 16 are punched through the bottom plate between them, the prefabricated piles are press-fitted, so that the through holes are as shown in FIG. 7 (b). It is filled with a lid 22.
[0035]
On the other hand, in FIG.7 (c), in order to integrate the lower end part 8 of the side wall 7, and the front-end | tip of the ready-made pile 9, the fixing mechanism 23 is used and it is covered with the cover material 24 after construction.
[0036]
After the above construction is performed, the entire work space 16 is filled with the filled concrete 25 as shown in FIG. 7A, and the portal support 6 and the ready-made pile 9 are integrated. It is configured.
[0037]
When the portal support 6 is configured in the ground 5 below the existing roadbed surface 3 by the above steps, the shaft is removed as shown in the cross-sectional view of FIG. The ready-made pile 9 in this state is installed along the side walls 7 and 7 of the gate-type support body 6 as seen in the plan view of FIG. Yes.
[0038]
FIG. 10 shows a process of forming an active space inside the portal support, which is performed after the portal support is constructed.
[0039]
In this step after the gate-type support body 6 is formed in the ground 5 under the existing roadbed surface 3, the laterally extending construction method is provided between the gate-type support bodies 6 and 6 installed on both sides of the bridge 4 for the track. The new girder 26 is replaced by a carrier erection method or the like.
[0040]
In addition, since the gate-type support 6 is integrated with the ready-made pile 9, the installation in the ground is solidified, so that the active space 10 is formed inside the gate-type support 6 together with this replacement. The range of utilization of the existing roadbed surface 1 on which the railway bridge 2 is constructed is expanded.
[0041]
The excavation for forming the active space 10 is performed while measuring the amount of subsidence at the ceiling 12 of the portal support 6, and the process of excavating the internal ground of the portal support 6 is thereby stably performed. It can be constructed.
[0042]
As described above, the construction method of the existing roadbed surface support according to the present invention comprises a gate-type support horizontally embedded in the ground below the existing roadbed surface, and a work space at the lower end of the side wall of the gate-type support. Forming a plurality of pre-made piles in the vertical direction from the work space toward the lower ground, filling the work space at the lower end of the side wall of the gate-type support body with concrete, and the gate-type support body and the pre-made piles And the process of forming an active space inside the gate-type support body, which suppresses the occurrence of mortar outbreak, ground uplift or subsidence of existing roadbed surface support caused by ground improvement While being constructed with high accuracy, an effective active space is formed inside the existing roadbed surface support.
[0043]
As mentioned above, although the present invention has been described in detail based on the embodiment, the construction method of the existing roadbed surface support according to the present invention is not limited to the above embodiment at all, and the form of the gate-type support As a matter of course, various changes can be made in the scope of the present invention with respect to the specific construction method and the like.
[0044]
【The invention's effect】
The construction method of the existing roadbed surface support body according to claim 1 comprises a gate-type support body embedded in the horizontal direction in the ground below the existing roadbed surface, and forms a work space at the lower end of the side wall of the gate-type support body A step of pressing a plurality of ready-made piles vertically from the work space toward the lower ground, filling the work space at the lower end portion of the side wall of the gate-type support body with the gate-type support body and the ready-made piles. Since it consists of a process of integrating and a process of forming an active space inside the portal support, it is cylindrical with a plurality of ready-made piles that are press-fitted vertically from the lower end of the side wall of the portal support. Taking advantage of the features of steel pipes, ground improvement work is unnecessary and the following effects are achieved.
1. Construction can be done without loosening the ground.
2. Does not cause mortar outbursts and ground uplifts like ground improvement.
3. The construction condition can be confirmed by eliminating the ground improvement, which makes it difficult to confirm the support strength, and simultaneously grasping the pile support force during press-fitting of a pre-made pile.
4). Since the legs of the gate-type support can be intensively supported vertically, the construction is not extensive as in ground improvement, and simultaneous press-fitting of a plurality of ready-made piles can be facilitated.
[0045]
The construction method of the existing roadbed surface support body according to claim 2 is the construction method according to claim 1 , wherein the work space formed in the gate-type support body and the lower end portion of the side wall is a horizontal pipe made of filled concrete. Constructed from the ceiling of the portal support that is embedded in the direction and the work space formed on the side wall of the portal support that is embedded in the vertical direction from the ceiling and filled with a cylindrical steel pipe filled with concrete. In addition to the above effects, it has the effect of maintaining a stable construction state while suppressing settlement.
[0046]
The construction methods of the existing roadbed surface support according to claim 3, working space in construction method according to claim 1 or 2, the press-fitting of the vertical prefabricated pile directed downwardly ground, which is formed in the side wall lower end portion In addition to the above effects, in addition to the above effects, the effect of constructing the ready-made piles in a stable state is suppressed. I play.
[0047]
The construction method of the existing roadbed surface support body according to claim 4 is the construction method according to any one of claims 1 to 3 , wherein the step of forming the active space inside the gate-shaped support body is a filled concrete cylinder. In addition to the above effects, the construction of the active space is stably constructed because the internal ground of the gate-type support is excavated while measuring the amount of settlement at the ceiling of the gate-type support made of steel pipe Has an effect that can be.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment in which an existing roadbed surface support according to the construction method of the present invention is applied to a bridge for a track. FIG. 2 is a cross-sectional view of a shaft built in the ground below the existing roadbed surface. [Fig. 3] Cross-sectional view under the existing roadbed to construct a portal support [Fig. 4] An embodiment of pulling a cylindrical hollow steel pipe from a shaft on the reaching side [Fig. 5] An embedded cylindrical hollow steel pipe Fig. 6 Process drawing for constructing ready-made piles from the working space formed at the lower end of the side wall of the gate-type support. Fig. 7 Integration of the gate-type support and the ready-made piles. FIG. 8 is a sectional view of the process of removing the vertical shaft. FIG. 9 is a plan view of an installed pile in the portal support. FIG. 10 is a process of forming an active space inside the portal support. [Fig. 11] Cross-sectional view of existing roadbed surface support construction [explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Existing roadbed surface support body, 2 Road, 3 Existing roadbed surface, 4 Bridge for track, 5 Ground, 6 Gate type support body, 7 Side wall, 8 Lower end part, 9 Ready-made pile, 10 Active space, 11 Filled concrete cylinder Steel pipe, 12 Ceiling, 13 Vertical shaft, 14 Chemical solution, 15 Cylindrical hollow steel pipe, 16 Working space, 17 PC steel strand, 17 'Traction device, 18 Excavator, 19 Concrete, 20 Jack device, 21 Straight pipe, 22 Lid , 23 Fixing mechanism, 24 Cover material, 25 Filled concrete, 26 New girder, 30 Existing roadbed surface support, 31 Tubular steel pipe, 32 Concrete, 33 Ground improvement, 34 Working space, 35 Lower ground, 36 Concrete pile 37 concrete,

Claims (4)

A step of forming a gate-type support body embedded horizontally in the ground below the existing roadbed surface, and forming a work space at the lower end of the side wall of the gate-type support body, vertically extending from the work space toward the lower ground A step of press-fitting a plurality of ready-made piles, a step of filling the work space at the lower end of the side wall of the gate-type support body with concrete and integrating the gate-type support body and the ready-made piles, and the inside of the gate-type support body A method for constructing an existing roadbed surface support characterized by comprising a step of forming an active space. The work space formed at the gate-type support and the lower end of the side wall is a ceiling of the portal-type support formed by embedding a filled concrete tubular steel pipe in the horizontal direction, and the filled concrete tubular steel pipe is vertically extended from the ceiling. The construction method for an existing roadbed surface support according to claim 1 , comprising a side wall of a gate-type support body embedded in a direction and a work space formed at a lower end portion of the side wall. The press-fitting of the ready-made pile in the vertical direction toward the lower ground is sequentially performed while adding the ready-made pile divided using the jack device arranged on the upper surface of the work space formed at the lower end of the side wall. The construction method of the existing roadbed surface support body of Claim 1 or 2 . The process of forming an active space inside the portal support is characterized by excavating the internal ground of the portal support while measuring the amount of settlement at the ceiling of the portal support made of filled concrete tubular steel pipe The construction method of the existing roadbed surface support body in any one of Claim 1 thru | or 3 .

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