JP3681817B2 - Support structure and support method for existing underground structures - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention generally relates to a support structure and a support method for an existing underground structure such as a buried pipe, a road or a lining tunnel for a railroad, and in particular, intersects such an existing underground structure directly below the structure. The present invention relates to a structure and a method for supporting an underground structure prior to excavation immediately below the underground structure in order to newly construct the structure.
[0002]
[Prior art]
One of the prior arts is to receive an existing underground structure from below, excavate from the ground surface to the bottom level of the existing structure, improve the ground directly under the underground structure, A plurality of tunnels are installed in the direction crossing the underground structure by a simple tunnel method, and pile materials such as pile driving machines and H-shaped steel are carried into the tunnels, and the guides are driven by pile driving work in each tunnel. A large number of support piles are created from the pit below, and a jack is installed between the support pile and the underground structure. Prior to excavation, the jack is operated to load the underground structure into the support pile. It is something to carry. Another one of the prior arts is to receive an existing underground structure at its lower side opposite to each other. As described in Japanese Patent Laid-Open No. 5-331866, A discontinuous underground wall is provided as a support structure, and an existing structure is received and supported by a bracket pedestal included in the support structure.
[0003]
[Problems to be solved by the invention]
One of the above prior arts is a work in the shaft, that is, a pile driver, an H-section steel to be the core material of the pile is carried into the narrow shaft, and the H-shaped steel is added to the ground under the shaft. Because it is a medium continuous wall construction, this conventional technology has poor workability, requires a long construction period, requires ground improvement and downhole excavation, and is expensive to construct. There's a problem.
[0004]
In addition, another one of the above prior arts is that the continuous or discontinuous underground walls are due to ground work, and therefore there are underground structures such as other buried objects in this prior art. There is a problem that it cannot be used at sites that hinder the construction of underground walls. Further, according to this prior art, continuous or discontinuous underground walls are provided as support structures on both sides of the underground structure, so that when another structure is to be constructed immediately below the underground structure, There is a risk that the support structure will be hindered. Furthermore, according to this prior art, since the underground structure is supported only at the lower side of the underground structure, in the case of an underground structure in which the interval between the bracket bases is large, the deflection due to its own weight increases. Further, when the underground structure is a lining tunnel for a subway, there is a problem that this conventional technology cannot be adopted in such a case because it is necessary to take into account the bending due to the influence of live weight.
[0005]
Therefore, the object of the present invention is basically to improve the workability of the work for supporting the existing underground structure, to shorten the construction period and to reduce the construction cost, and in particular, to improve the safety of the existing underground structure. It is to support the underground structure without affecting the sex.
[0006]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention secures a support pile to both sides of an existing underground structure to support the underground structure, and supports the suspension girder with the support pile. The basic structure of the support structure and support method for the underground structure is to connect the underground structure to the suspension structure and suspend the structure. Furthermore, the support structure according to the present invention is a plurality of support piles that are installed at intervals on both sides of the underground structure and reach the top surface of the underground structure from the ground below the underground structure. A support pile consisting of a lower pile portion, an upper pile portion and a jack arranged between both pile portions, means for fixing each support pile to the side of the underground structure, and arranged across the underground structure A suspension girder supported by the support pile, and a means for connecting the underground structure and the suspension girder, which is installed through the center of the underground structure at an interval in the axial direction. Including. Each of the fixing means and the connecting means includes a steel bar and a resin adhesive.
[0007]
Furthermore, the support method according to the present invention excavates the ground from the ground surface to the top surface of the existing underground structure, and on both sides of the underground structure, from the ground below the underground structure, the top surface of the underground structure. The lower pile portion of the support pile that reaches the bottom is installed from the ground below the underground structure to the vicinity of the bottom of the underground structure, excavating the ground from the level of the top surface of the underground structure to the level of the bottom, A jack is installed on a lower pile portion of the support pile, and an upper pile portion of the support pile is installed from the jack to the top surface of the underground structure, and an upper pile portion of each support pile is placed on the underground structure. A connecting means that is fixed to a side, a suspension girder is arranged across the underground structure, and the suspension girder is supported by the support pile, and passes through substantially the center of the underground structure at an interval in the axial direction. To connect the bottom of the underground structure and the suspension girder , For subsequent drilling directly below the underground construction, comprising causing play a load of the jack to actuate 該地 under construction in the lower stake part. The upper pile portion is made of H-shaped steel, a hole is made in the flange portion of the H-shaped steel and the side wall of the underground structure, a steel rod is inserted into the hole, and the steel rod is fixed with a resin adhesive. By doing so, the upper pile portion is fixed to the side portion of the underground structure. Moreover, the said upper pile part is integrated with the side wall of the said underground structure by reinforced concrete.
[0008]
[Effects of the invention]
According to the present invention, since the pile driving work is not performed directly under the existing underground structure, the workability of the work for supporting the existing underground structure is improved, the construction period is shortened, and the construction cost is reduced. be able to. In addition, the support pile is fixed to both sides of the existing underground structure to support the underground structure, the suspension girder is supported by the support pile, and the underground structure is connected to the suspension girder. As a result, the safety of existing underground structures can be ensured.
[0009]
Embodiment
Referring to FIG. 1, an existing underground structure 12 supported by a support structure 10 according to the present invention for digging directly under an existing underground structure is shown. This underground structure 12 is a lining tunnel for a subway in the illustrated example. Other underground structures include buried pipes and road lining tunnels.
[0010]
The support structure 10 includes a plurality of support piles 14 disposed at intervals on both sides of the underground structure 12. Each support pile 14 has a length that reaches the top surface of the underground structure from the ground below the underground structure 10 as a whole. Moreover, each support pile 14 consists of the lower pile part 14a, the upper pile part 14b, and the jack 14c arrange | positioned between both pile parts. In the state where the support structure 10 supports the underground structure 12 as shown in the drawing, each jack 14c is in the operating state and receives the load applied to the upper pile portion 14b and the lower pile portion 14a. Yes. As for each support pile 14, the upper pile part 14b is being fixed to the side part of the underground structure 10 with the fixing means 16. As shown in FIG. The fixing means 16 includes a plurality of steel bars 16a and a resin-based adhesive that fixes the steel bars 16a to an underground structure. A plurality of suspension girders 18 are arranged across the underground structure 12, and each suspension girder is supported by the support pile 14 via a receiving girder 20. Further, a connecting means 22 for connecting the underground structure 10 to the hanging girder 18 is disposed so as to penetrate substantially the center thereof at an interval in the axial direction of the underground structure 12. The connecting means 22 includes a plurality of steel bars 22a and a resin-based adhesive that fixes the steel bars 22a to an underground structure.
[0011]
In the construction of the support structure 1 0, as shown in FIG. 2, after providing the mountain Tomekabe 26 surrounding the excavation zone 24, bulldozer the ground from the surface 28 to the top surface 30 of the underground construction 12 32, backhoe 34 Drill using a drilling machine such as. The surface 28 is provided with a lid 36 for safety and traffic.
[0012]
Next, as shown in FIG. 3, a plurality of pile holes 40 are drilled at intervals on each side of the underground structure 12 and in close proximity to the side walls of the underground structure using a drilling device 38. To do.
[0013]
After drilling each pile hole, as shown in FIG. 4, the ground from the level of the top surface 30 of the underground structure 12 to the level of its bottom surface 43 is excavated, and H-shaped steel is used as the pile core in each pile hole. And mortar 42 is filled as a filler. The tip of the subsequent H-section steel is connected to the rear end of the H-section steel with a bolt and filled with mortar, and this is repeated until the bottom portion of the support pile 10, that is, from below the underground structure 12 to the vicinity of the bottom surface 43. The lower pile portion 14a is created. At this time, the mortar 42 is filled up to a later excavation level 44 in consideration of excavation. A jack 14c is arranged at the tip of each lower pile portion 14a, and then an H-shaped steel is arranged on the jack 14c to provide an upper pile portion 14b from the top of the jack to the top surface 30 of the underground structure 12, This is fixed to the side of the underground structure 12 as will be described later. The H-section steel can be connected by welding instead of the bolt.
[0014]
In order to fix each upper pile portion 14b, a large number of holes reaching both sides of the underground structure 12 through both flanges of the H-shaped steel are formed, and a resin adhesive (for example, a polyester film) is partitioned in the holes. (Resin composition filled in two chambers) and a steel rod 16a such as a deformed reinforcing bar having a thread groove at the end thereof are inserted to fix the steel rod to the underground structure 12, and a nut (not shown) ). Thus, each upper pile part 14b is fixed to the side part of the underground structure 12 by the fixing means 16 which consists of a resin adhesive, the steel bar 16a, and a nut.
[0015]
Thereafter, reinforcing bar (not shown) disposed between the upper Katakui portion 1 4b, these place the mold (not shown) to Da設concrete surrounding, thereby lower stake moiety through a jack 14c Reinforced concrete reinforced walls 48 (FIG. 5) integrated with both sides of the underground structure 12 supported by 14a are formed on both sides of the underground structure 12.
[0016]
Next, as shown in FIG. 6, the girder 20 is arranged on the accessory wall 48, and the hanging girder 18 crossing the underground structure 12 is arranged on the girder. As a result, the receiving girder 20 is supported by the support pile 14 via the accessory wall 48, and the hanging girder 18 is supported by the supporting pile 14 via the receiving girder 20.
[0017]
Thereafter, as shown in FIG. 7, a hole penetrating the substantially central portion at an interval in the axial direction of the underground structure 12 is vertically drilled, and the same resin-based adhesive as described above in each hole, A steel bar 22a such as a modified PC rebar having a thread groove at the end is inserted to fix the steel bar to the underground structure 12, and the upper end of the steel bar is fixed to the suspension girder 18 with a nut 50. Thereby, the underground structure 12 and the hanging girder 18 are connected by the connecting means including the resin adhesive, the steel rod 22a and the nut 50, and the load of the underground structure 12 is supported by the support pile 14 via the hanging girder 18. .
[0018]
Finally, excavation is performed immediately below the underground structure 12 to a predetermined excavation level 44 (see FIG. 1). Prior to this excavation, the jack 14c is operated to receive the load of the underground structure 12, and this is carried by the lower pile portion 14a. As a result, the support piles 14 are fixed to both sides of the underground structure 12 to support the underground structure, the suspension girders 18 are supported by the support piles 14 , and the underground structures are connected to the suspension girders. The ground under the underground structure can be excavated while the structure is suspended and the safety of the underground structure 12 is ensured.
[Brief description of the drawings]
FIG. 1 is a view showing a state in which an underground structure is supported by a support pile according to the present invention.
FIG. 2 is a diagram showing excavation conditions up to the top surface of an underground structure.
FIG. 3 is a diagram showing a drilling situation for constructing support piles on both sides of an underground structure.
FIG. 4 is a cross-sectional view of an underground structure to which a built support pile is fixed.
FIG. 5 is a partially enlarged side view of an underground structure to which a built support pile is fixed.
FIG. 6 is a view showing a situation in which a hanging girder arranged across an underground structure is supported by a support pile via a receiving girder.
FIG. 7 is a view showing a state in which an underground structure is connected to and suspended from a hanging girder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Support structure 12 Underground structure 14 Support pile 14a Lower pile part 14b Upper pile part 14c Jack 16 Fixing means 16a Steel bar 18 Suspension girder 20 Support girder 22 Connecting means 54 Steel bar 56 Nut

Claims (8)

  A plurality of support piles fixed to both sides of an existing underground structure and supporting the underground structure, each comprising a lower pile portion, an upper pile portion, and a jack disposed between both pile portions. A support structure for an underground structure, comprising: a support pile; and a suspension girder supported by the support pile and connected to the underground structure to suspend the underground structure.   A plurality of support piles fixed to both sides of an existing underground structure and supporting the underground structure, a suspension girder supported by the support pile, and an interval between them in the axial direction of the underground structure A support structure for an underground structure, including an underground structure and a means for connecting the suspension girder, which are installed through the center.   A support structure for supporting the underground structure to excavate directly beneath the existing underground structure, the support structure being installed at intervals on both sides of the underground structure from the ground below the underground structure A plurality of support piles reaching the top surface of the underground structure, each comprising a lower pile portion, an upper pile portion, and a jack disposed between the two pile portions; and each support pile on the side of the underground structure Means that are fixed across the underground structure, suspended girders that are supported by the support piles, and are installed through the center of the underground structure at intervals in the axial direction. A supporting structure for an existing underground structure, comprising: an underground structure and a means for connecting the suspension girder.   A support pile composed of a lower pile portion, an upper pile portion, and a jack disposed between both pile portions is fixed to both sides of the existing underground structure to support the underground structure, and the suspension pile is supported by the support pile. The underground structure is supported by connecting an underground structure to the suspension girder and suspending the structure.   Support piles are fixed to both sides of the existing underground structure to support the underground structure, and the suspension girders are supported by the support piles, and penetrate substantially through the center of the underground structure at intervals in the axial direction. A method for supporting an underground structure, wherein an underground structure is connected to the suspension girder by a connecting means arranged as described above, and the structure is suspended.   A method of supporting the underground structure in order to excavate an existing underground structure, excavating the ground from the surface to the top surface of the existing underground structure, and forming the underground structure on both sides of the underground structure. The lower pile portion of the support pile extending from the ground below the structure to the top surface of the underground structure is installed from the ground below the underground structure to the vicinity of the bottom of the underground structure, and the top surface of the underground structure Excavating the ground from the level of the bottom to the level of the bottom, installing a jack on the lower pile portion of the support pile and installing the upper pile portion of the support pile from the jack to the top surface of the underground structure The upper pile portion of each support pile is fixed to the side of the underground structure, a suspension girder is arranged across the underground structure, and the suspension girder is supported by the support pile, and the axis of the underground structure By connecting means penetrating almost the center at intervals in the direction In order to connect the bottom of the underground structure and the suspension girder, and then excavate directly below the underground structure, the jack is operated to load the lower pile portion with the load of the underground structure. Including existing underground structure support methods.   The upper pile portion is made of H-shaped steel, a hole is made in the flange portion of the H-shaped steel and the side wall of the underground structure, a steel rod is inserted into the hole, and the steel rod is fixed with a resin adhesive. The supporting method according to claim 6, wherein the upper pile portion is fixed to a side portion of the underground structure.   The support method according to claim 6, wherein the upper pile portion is integrated with a side wall of the underground structure by reinforced concrete.

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