JPH0128200B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for excavating a lateral hole under a track necessary for constructing an underground structure such as an underground passage that crosses the track.

As a countermeasure against railroad crossing accidents and road traffic congestion, there is a strong desire to create grade-separated intersections between railways and roads, and to this end, construction projects such as those shown in Figures 1 and 2 have recently been carried out.

In other words, vertical shafts B and B' are excavated on both sides of the planned underground structure sandwiching track A, and a large number of steel pipes are installed in the ground at an appropriate depth under track A in a direction approximately perpendicular to track A. After constructing pipe roof protection by horizontally press-fitting pipes C in close parallel to each other, shoring D is installed to support the earth retaining and steel pipes on the side from one shaft to the other. A method is being implemented in which the tunnel is excavated while the tunnel is being constructed.

However, according to this method, since the steel pipe is buried underground, a certain amount of earth cover E is required between the rail and the steel pipe, and the underground structure must be built that much deeper. As a result, the slope F for entering the structure becomes steep or the slope portion becomes long, and the construction cost increases because the steel pipes cannot be removed.

In order to eliminate such drawbacks, the present invention supports the lower surface of the track with a plurality of steel girder members without forming a pipe roof protection work, and horizontal holes are formed in the ground on the lower surface side of the steel girder members. The present invention provides a method for excavating a horizontal hole under a track that does not require earth covering.

To explain an embodiment of the present invention with reference to the drawings, a track bed ballast 3 under the track consisting of a rail 1 and sleepers 2, 2 supporting the rails 1, 1 is placed between each sleeper 2, 2 in a direction perpendicular to the rail 1. As shown in FIG. 9, a plurality of grooves a penetrating between both sides of the track bed ballast 3 are formed in a predetermined length portion of the track by excavation.

At this time, the roadbed 4 may also be excavated if necessary. Next, after spreading mortar 5 evenly on the bottom of this excavated groove, each groove a has a depth of H that is slightly lower than the depth of groove a.
Insert and lay the shaped steel girder 6 over the entire width of the roadbed 4, and then place it along the upper surface of the steel girder 6 in the gap 7 between the upper surface of the steel girder 6 and the lower surface of the rail 1. Then insert the insulating member 8 made of an insulating material such as wood, connect and secure the rail 1 and the insulating member 8 with a suitable fastener 9, and connect the insulating member 8 and the steel girder 6 with bolts 22 or the like. By fixing, the train load is supported by the roadbed 4 via the rail 1, the fastening material 9, the insulating member 8, and the steel girder 6.

Excavation bottom surface 1 of the structure to be constructed in this way
Hypothetical ground collapse line drawn from both ends of 1 12, 12
A plurality of parallel steel girder members 6, 6...6 in the area of
After constructing the hairpin girder 10, a splice material 13 is constructed in a suitable place on the upper surface of the steel girder material 6 in parallel with the rail 1, and the steel girder materials 6, 6...6 are arranged in parallel by the splice material 13. to stabilize the orbit. Sleeper 2 will be removed at this point.

Next, vertical shafts 23 and 23' are constructed in the ground on both ends of the hairpin girder 10 made of steel girder groups, that is, on both sides of the track, as shown in FIG.
A self-propelled excavator 14 having the cross-sectional shape of the structure is used to move the hairpin girder 1 toward the other shaft 23'.
0 steel girders 6 and the roadbed 4 while supporting the side earth pressure.
excavate.

As shown in FIG. 8, the self-propelled excavator 14 has a plurality of steel sheet piles 1 on both sides of a movable frame, which is made up of a support frame 15 assembled in a frontal shape and connected in the front-rear direction.
6, 16...16 are attached so as to be slidable back and forth, and the horizontal hole is drilled while alternately propelling the steel sheet piles 16 and the movable support frame 15 using the frictional force with the earth pressure acting on these steel sheet piles 16 as a propulsion reaction force. It is something to be excavated.

As this excavator 14 digs, the excavator 1
As shown in Fig. 7, the upper girder 18 is inserted into the rear horizontal hole of No.
A shoring 17 consisting of a lower girder 19 and earth retaining columns 20, 20 is assembled, and this shoring 17 supports the steel girder 6 and the lateral earth pressure. At this time, the track bed ballast 3 is also removed at the same time. In addition, shoring 17
The outer surface of the earth retaining sheet pile 21 is spanned between the outer parts of the adjacent earth retaining columns 20, 20, and is locked therewith to cover the outer surface of the earth retaining column.

In this way, while the excavator 14 excavates the roadbed 4 and erects the shoring 17 in sequence, the other vertical shaft 2
3' and drill a horizontal hole 24 under the track.

Thereafter, an underground structure that will serve as a passage is constructed within the horizontal hole 24 by normal means, and sleepers are laid while placing bed ballast between the steel girders 6 and 6. Pull it out and restore it to its original state.

Furthermore, if the lower surface of the steel girder 6 is uneven, a packing may be interposed between the upper girder 18 and the steel girder to absorb the uneven surface.

Next, since the width of the underground structure is quite wide, a large excavator is required to excavate the horizontal holes for constructing such a structure at once, which increases the cost. By performing the excavation method described in the above embodiment by dividing it in the horizontal direction, horizontal holes 24a and 24b with an appropriate interval are excavated between the vertical holes, and the remaining holes sandwiched between these horizontal holes 24a and 24b are ground 26
While excavating with a normal excavator such as a shovel, connect both ends of the upper girder 27 to the opposite ends of the upper girders 18a and 18b built in the horizontal holes 24a and 24b, and connect the lower girders of the horizontal holes 24a and 24b. 19a and 19b are similarly connected by a lower girder 28, and shoring structures 17a and 17b are erected.

In this case, the steel girders 6, 6...6 are the upper girder 18a,
18b and the joint girder 27, and the earth retaining columns 20a, 20b are supported by the upper girder 18a, 18b.
This becomes the intermediate support of the joint girder 27.

Thereafter, the trajectory is restored to its original state in the same manner as in the previous embodiment.

As described above, the present invention involves excavating grooves perpendicular to the track in the track bed ballast between the sleepers supporting the rail laid on the track above the horizontal hole to be excavated, and inserting steel girders into these grooves. At the same time, an insulating member is interposed between the lower surface of the rail and the upper surface of the steel girder material, and the rail is supported by the steel girder material.Then, after removing the sleepers, the steel girder material is installed from one end to the other. Before proceeding, a horizontal hole is dug in the ground below the steel girder material, and in the horizontal hole being excavated, earth retaining sheet piles on the side wall of the hole and shoring to support the steel girder material and lateral earth pressure are erected. However, since this relates to the method of excavating horizontal holes under the tracks, which is characterized by drilling and penetrating horizontal holes in the ground under the tracks, the steel girders that receive the rails are designed to hold the trackbed ballast between each sleeper. Since it is installed in a trench formed by excavation, the installation work can be done more easily and accurately than the method of driving it into the ground. The steel girder that directly supports the rail in this way has no earth cover, and the horizontal hole is drilled along the bottom surface of the steel girder. , it is possible to drill a horizontal hole into the ground as close as possible to the rail, and therefore it is possible to shorten the approach slope to the underground structure constructed in the horizontal hole, and also to create a gentle slope. In addition, it is possible to efficiently excavate side holes without stopping train operations, eliminating the need for night work, and the excavation period is shortened, which also shortens the running period of trains. It is possible.

Furthermore, since the steel girders that receive the rails can be removed after the horizontal hole is excavated, the construction cost is low and the system is economical.

[Brief explanation of drawings]

Fig. 1 is a construction drawing of the conventional method, Fig. 2 is a simplified longitudinal sectional front view thereof, Figs. 3 to 11 show an embodiment of the present invention, and Figs. 3 to 6 are construction process diagrams. , Figure 7 is a simplified vertical front view of the assembled shoring, Figure 8 is a simplified vertical front view of the excavation being performed with a self-propelled excavator, and Figure 9 is a simplified vertical front view of the steel girder section that receives the rail. Enlarged vertical front view, Fig. 10 is a side view, Fig. 11
The figure is a simplified longitudinal sectional front view showing another embodiment of the present invention. 1...rail, 2...sleeper, 3...trackbed ballast, 4...
Roadbed, 6... Steel girder, 8... Insulating member, 14... Excavator, 17... Shoring, 23, 23'... Vertical shaft, 24...
Horizontal hole, 25...underground structure.

Claims (1)

[Claims] 1. In the upper part of the horizontal hole to be excavated, grooves perpendicular to the rails are excavated in the bed ballast between the sleepers that support the rails laid on the track, and steel girders are laid in these grooves, and the bottom surface of the rails is The rail is supported by the steel girder by interposing an insulating member between the upper surface of the steel girder and the steel girder, and after removing the sleepers, the steel girder is moved from one end of the steel girder to the other. A horizontal hole is excavated in the lower ground, and while the earth retaining sheet pile on the side wall of the hole, the steel girder material, and a support to support the lateral earth pressure are erected in the horizontal hole being excavated, the horizontal hole is laid in the ground under the track. A horizontal hole drilling method under the track, which is characterized by drilling and penetrating a hole.