JPH0742155A - Suspending method for shore strut in shore strut earth retaining method and length adjusting mechanism for shore strut - Google Patents

Abstract

PURPOSE:To quickly suspend a shore strut between earth retaining walls and reduce the cost of the materials to be used. CONSTITUTION:A plurality of shore strut members 11 are connected to form a shore strut 7, length adjusting mechanisms 17 are provided on the shore strut members 11 located at both ends of the shore strut 7, and the shore strut 7 is suspended between earth retaining walls 5 so that the length adjusting mechanisms 17 face the earth retaining walls 5. Contact plates 21 of the length adjusting mechanisms 17 are extended on the earth retaining wall 5 side of the end faces 13, and the contact plates 21 are brought into pressure contact with the earth retaining walls 5. A preload is applied to the shore strut 7, and the slackness of the connection portions of the shore strut members 11 is removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a girder for supporting a gutter wall to prevent the surrounding ground from collapsing in underground excavation work, and a suitable length of the girder to carry out the method. It is related to the adjusting mechanism.

[0002]

2. Description of the Related Art Conventionally, in underground excavation work, a dam wall is constructed by a continuous underground wall or the like, and a girder is installed between facing dam walls to prevent the surrounding ground from collapsing. The cut-and-mountain construction method is generally used. Among them, in underground excavation work such as subway construction where excavation is performed from above the road surface, it is necessary to quickly erection a girder between the retaining walls in order to restore the road surface and allow passage immediately after the primary excavation. For this reason, a crossbeam is often installed directly between the cliff walls. By the way, generally, a girder is configured by connecting a plurality of girder members made of H-shaped steel having a standardized length dimension in advance. In order to counteract earth pressure of the retaining wall, a screw jack, etc. is provided in the middle axial direction of the cutting beam, and both ends of the cutting beam are pressed against the mountain retaining wall, so that the cutting beam is preloaded and a plurality of cutting beams are applied. The looseness of the joint of the member is eliminated, and an axial force is applied to the beam to create a reaction force against the earth pressure of the retaining wall.

However, as described above, since the truss members constituting the truss are formed in a standardized length dimension in advance, the length of the truss connecting them is not necessarily the interval between the retaining walls. Does not always coincide with, and in most cases, a slight gap is formed between the end of the girder and the retaining wall. Therefore, conventionally, the gap between the end of the beam and the retaining wall has been filled as follows. (B) Fill the gap between the end of the beam and the retaining wall with concrete. (B) A giraffe jack (screw jack) is provided in the joint portion of the beam member to jack the beam members on both sides in the axial direction. (C) A liner plate such as an iron piece is placed in the gap between the end of the beam and the retaining wall.

[0004]

However, the following problems occur in the above-mentioned prior art. In the case of (a), if the concrete does not exhibit a predetermined strength, the girder cannot be preloaded, a waiting time is spent until the strength appears, and excavation work is delayed.
In the case of (b), the joint reinforcement of the giraffe jack provided in the joint portion of the beam member is complicated, and the jack is expensive. In the case of (C), since the gap between the end of the girder and the cliff wall is not constant, it is necessary to prepare multiple types of liner plates with different thicknesses. However, since it is necessary to prepare a useless plate that is not actually used, the cost is high. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cutting girder dam construction method capable of quickly constructing a girder between the girder walls and reducing the cost of materials used. It is an object of the present invention to provide a method of constructing a truss and a mechanism for adjusting the length of the truss suitable for carrying out the method.

[0005]

Means for Solving the Problems To achieve the above object, the present invention is to install a cutting beam between the mountain retaining walls which are opposed to each other in the method of constructing a mountain girder retaining structure. The both ends of the girder are bridged to face the mountain stop wall, and jack means is provided between at least one end of the girder and the mountain stop wall facing the end, and the jack means is provided. Is extended in the longitudinal direction of the beam.

Further, the present invention is a mechanism for adjusting the length of a truss, which is inserted through at least one end face of the truss and extends in the longitudinal direction of the truss and is parallel to each other. A plurality of shaft members, an abutment plate attached to each shaft member portion located outside the end surface, and extending in parallel with the end surface, and a fixing member that fixes the position of each shaft member with respect to the end surface. And a member. Further, in the present invention, the shaft member is configured by a screw rod, a hole through which the screw rod is inserted is formed in the end surface, and the fixing member is
Both sides of the end face are composed of nuts screwed to the screw rod.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show an underground structure constructed by applying the present invention. FIG. 1A is a plan sectional view and FIG. 1B is a longitudinal sectional view. In these figures, 1 is the ground, 5 is the ground 1
Deck wall consisting of continuous concrete underground wall placed in
Reference numeral 7 is a girder directly installed between the opposing dam walls 5 in order to counteract the earth pressure applied from the ground 1 to the dam walls 5 and prevent the ground 1 from collapsing. Further, 8 is an excavated ground formed by the primary excavation of the ground 1, 9 is a pile pile driven into the ground 1 along the direction in which the cutting beam 7 is received, and 10 is the above-mentioned along the erection direction of the cutting beam 7. It is a bracket provided on the shelf pile 9, and the cutting beam 7 is held by the bracket 10.

As shown in FIG. 1A, the cutting beam 7 is composed of a plurality of cutting beam members 11 having an appropriate length corresponding to the distance between the mountain retaining walls 5 facing each other. Each of the truss members 11 is made of H-shaped steel or the like, and as shown in FIG. 2, substantially square end faces 13 corresponding to the outer shape of the trellis members 11 are provided at both ends in the longitudinal direction X of the truss members 11. Holes 15 at the four corners of the end face 13.
Are formed. Beam member 11 configured in this way
Contact the end faces 13 of two adjacent beam members 11 to align the positions of the holes 15 of the two beam members 11.
A bolt (not shown) is inserted into the hole 15 and fixed with a nut (not shown), so as to be connected in the longitudinal direction X.
Reference numeral 17 in FIG. 1B is a length adjusting mechanism (corresponding to a jack means) according to one embodiment of the present invention. In this embodiment, the length adjustment is performed on the beam members 11 at both ends of the beam 7. A mechanism 17 is provided.

FIG. 3 shows the length adjusting mechanism 17 shown in FIG.
It is a perspective view showing a schematic structure of. As shown in FIG. 3, the length adjusting mechanism 17 of the present embodiment includes four screw rods 19, an abutting plate 21, an adjusting nut 23, and a fixing nut 25. A male screw 27 is formed on the peripheral surface of the screw rod 19 and is inserted into the hole 15 of the end surface 13 of the beam member 11. The contact plate 21 is formed in a substantially square shape slightly smaller than the end surface 13 of the beam member 11, and the base end 29 of the screw rod 19 is provided at each of four corners thereof.
Are attached vertically. Each screw rod 19 is attached to the end face 13
In the state of being inserted into the hole 15 of the contact plate 21 and the end surface 13
Is almost parallel to.

The adjusting nut 23 is screwed into each screw rod 19 before being inserted into the hole 15, and is located outside the end face 13 after being inserted into the hole 15. Further, the fixing nut 25 is screwed from the tip 31 of each screw rod 19 after inserting each screw rod 19 screwed with the adjusting nut 23 into the hole 15. still,
In this embodiment, the adjusting nut 23 and the fixing nut 25 fix the position of each screw rod 19 with respect to the end surface 13 to form a fixing member.

The length adjusting mechanism 17 constructed as described above.
In the case of erection of the girders 7 including the gutters 5, first, a pair of gutters 5 made of continuous concrete underground walls are formed in the ground 1, and the gutters 7 are formed between the gutters 5. A plurality of shelf piles 9 are driven in at one place in the ground along the receiving direction at intervals, and primary excavation is performed between the retaining walls 5. Next, at the height part of each shelf pile 9 exposed on the excavated ground 8 formed by the primary excavation, the cut beam 7 is installed.
In the vicinity of the seam of No. 1, the bracket 10 is attached along the erection direction of the girder 7, and as shown in the enlarged perspective view of FIG. The plate 4 is attached to the five retaining walls on the extension line, and the bracket 10 is also attached to the plate 4. Next, a plurality of girder members 11 are connected to each other to form a girder 7 having a length close to the interval between the gutter walls 5, and both ends of the girder 7 are supported by the brackets 10 of the gutter wall 5. At the same time, the middle portion of the cutting beam 7 is supported by the bracket 10 of each shelf pile 9,
The cutting beams 7 are bridged between the mountain retaining walls 5 so that the length adjusting mechanisms 17 of the mountain beam members 11 located on both ends of the mountain facing the mountain retaining walls 5 as shown in FIG.

If the beams 7 are laid between the cliff walls 5,
As shown in FIG. 5, the adjusting nut 23 of the length adjusting mechanism 17 is screwed toward the tip 31 side of each screw rod 19,
As a result, the base end 29 side portion of each screw rod 19 extends from the hole 15 toward the outside of the end face 13. The length of the extending portion of each of the screw rods 19 on the side of the base end 29 is determined by
Then, the contact plate 21 is abutted against the mountain stop wall 5 via the plate 4 by adjusting according to the gap S between the end face 13 of the beam member 11 and the end face 13. At this time, the fixing nut 25 is not screwed into the thread groove 27 of each screw rod 19, or is screwed to the tip 31 side of each screw rod 19.

When the contact plate 21 is applied to the mountain retaining wall 5, the adjusting nut 23 is slightly screwed to the tip 31 side of each screw rod 19 so that the end face 13 and the mountain retaining wall 5 are separated from each other. The screw rods 19 are stretched between them to pre-load the cut beams 7, and the connection portions between the cut beam members 11 forming the cut beams 7 are loosened to fix the cut beams 7 to the pair of retaining walls 5. Temporarily hold the installation condition between the two.

Further, as shown in FIG. 5, the fixing nut 25 is brought into contact with the inside of the end surface 13 of the cutting beam member 11, and the fixing nut 25 and the adjusting nut 23 fix the end surface 13 of the cutting beam member 11. Tighten and fix the position of each screw rod 19 and the contact plate 21 with respect to the end face 13. When the above adjustment work is completed, the gap S between the mountain wall 5 and the contact plate 21 of the length adjusting mechanism 17 forms a formwork and concrete C is poured to fill the gap S. When the concrete C is solidified, the position of the contact plate 21 with respect to the end surface 13 of the cut beam member 11 is fixed, and the end surface 13 of the cut beam member 11 is fixed to the mountain stop wall 5, whereby the cut beam 7 is formed. It is fixed in a erected state between the pair of cliff walls 5.

As described above, according to this embodiment, a plurality of beam members 11 are connected to each other to form the beam beam 7, and the beam beam members 11 located at both ends of the beam beam 7 have a length adjusting mechanism 17. Is provided, and the crossbeam 7 is bridged between the cliff walls 5 so that the length adjustment mechanism 17 faces the cliff walls 5, and the contact plate of the length adjustment mechanism 17 is provided on the ridge wall 5 side of the end face 13. 21 is extended so that the contact plate 21 is pressed against the retaining wall 5. Therefore, even if a gap S occurs between both ends of the girder 7 and the mountain stop wall 5, the gap S
Can be easily filled by extending the contact plate 21 of the length adjusting mechanism 17, and the cost of materials used can be reduced as compared with the case of using a giraffe jack or a liner plate. Further, by pressing the contact plate 21 against the mountain stop wall 5 via the plate 4, it is possible to preload the cutting beam 7 and to loosen the connecting portion of each cutting beam member 11, so that earth pressure can be applied. It is possible to promptly oppose each other, and moreover, the girders 7 can be quickly installed between the cliff walls 5. Then, the contact beam 21 is pressed against the mountain retaining wall 5 side through the plate 4, so that the cross beam 7 is temporarily held in the installed state between the mountain retaining walls 5, so that it is driven into the gap S. The next excavation work or the like can be immediately performed without waiting for the solidification of the concrete C.

Further, according to the present embodiment, the screw rod 19 is inserted into the hole 15 of the end face 13 of the beam member 11 facing the mountain wall 5 and extends from the hole 15 to the outside of the end face 13. The abutment plate 21 extending in the direction orthogonal to the longitudinal direction X is attached to the base end 29 of the, and the adjustment nut 23 is screwed to the base end 29 side portion of the screw rod 19, and the end face from the hole 15 is attached. The length adjusting mechanism 17 is configured by screwing a fixing nut 25 to the tip 31 side portion of the screw rod 19 extending inside 13. Therefore, by adjusting the length of the screw rod 19 extending to the outside of the end surface 13 by screwing the adjusting nut 23, the position of the contact plate 21 connected to the beam member 11 is set to the gap S. The length of the cutting beam 7 in the longitudinal direction X can be adjusted according to the interval between the mountain retaining walls 5 on which the cutting beam 7 is installed, and these can be adjusted with screw rods, nuts, and plate materials. This can be achieved with an inexpensive configuration.

In the present embodiment, the case where the cross beams 7 are installed between the opposing cliff walls 5 has been described. For example, FIG.
As shown in FIG. 3, when the bulging 33 is provided inside the mountain retaining wall 5, the abutting plate 21 of the length adjusting mechanism 17 is abutted against the bulging 33 and the abutting waving is performed. If the cross beam 7 is installed between the parts 33, the same effect as in the previous embodiment can be obtained. Further, in the present embodiment, the case where the length adjusting mechanism 17 is provided in a part of the plurality of beam members 11 constituting the beam beam 7 has been described. The present invention also applies to beams.

Further, in this embodiment, the length adjusting mechanism 17 is provided on the beam members 11 at both ends of the beam 7, but the length adjusting mechanism is provided on only one end face in the longitudinal direction of the beam. May be. In addition, in this embodiment, the shaft member is the screw rod 1.
9 and the fixing member is composed of the adjusting nut 23 and the fixing nut 25. For example, the shaft member is composed of a rod body having a plurality of engaging recesses formed on its circumferential surface along the axial direction. The structure of the shaft member and the fixing member is the one shown in the present embodiment, such as the fixing member is constituted by an engaging member that can be engaged with the engaging recess of the rod body and is locked to the end surface of the beam. Not limited to. Further, in this embodiment, after fixing the positions of the screw rods 19 and the contact plates 21 with respect to the end face 13, the form is assembled in the gap S between the mountain stop wall 5 and the end face 13 of the beam member 11 facing this. Although the concrete C was poured to fill the gap S, the concrete casting may be omitted.

[0019]

As described above, according to the present invention, in constructing a crossbeam between the mountain barrier walls facing each other in the mountain girder dam construction method, the crossbeam is bridged between the mountain dam walls. Both ends of the cut beam are made to face the mountain stop wall, and a jack means is provided between at least one end portion of the cut beam and the mountain barrier wall facing the end portion, and the jack means is provided at the cut beam. Since it is made to extend in the longitudinal direction, it is possible to erected a girder between the cliff walls quickly and reduce the cost of materials used. Further, according to the present invention, there is provided a mechanism for adjusting the length of the cross beam, the mechanism being inserted through at least one end surface of the cross beam, extending in the longitudinal direction of the cross beam and parallel to each other. A plurality of shaft members, an abutment plate attached to each shaft member portion located outside the end surface, and extending in parallel with the end surface, and a fixing member for fixing the position of each shaft member with respect to the end surface. Since the configuration is provided, the length of the cutting beam can be adjusted according to the length between the opposing pressure plates, and the cutting beam length adjusting mechanism that can perform the next excavation work immediately after installation can be provided at low cost.

[Brief description of drawings]

1 shows an underground structure constructed by applying the present invention, FIG. 1 (a) is a plan sectional view, and FIG. 1 (b) is a longitudinal sectional view.

FIG. 2 is a perspective view of an essential part showing a schematic configuration of a truss member that constitutes the truss shown in FIG.

FIG. 3 is a perspective view showing a schematic configuration of a length adjusting mechanism shown in FIG. 1 (b).

FIG. 4 is an enlarged perspective view showing a state in which an end portion of the girder of FIG. 1 spanning between the mountain retaining walls is supported on the mountain retaining wall side.

FIG. 5 is an explanatory view showing a usage state of the beam member having the length adjusting mechanism shown in FIG.

FIG. 6 is a plan cross-sectional view of an underground structure in which a girder provided with the length adjusting mechanism shown in FIG. 3 is installed between the wavings arranged inside the mountain stop wall.

[Explanation of symbols]

 7 Cut Beam 11 Cut Beam Member 13 Cut Beam Member End Face 15 Hole 17 Length Adjusting Mechanism 19 Screw Rod 21 Abutment Plate 23 Adjusting Nut 25 Fixing Nut 27 Screw Groove 29 Screw Rod One End 31 Screw Rod Other End

Claims (3)

[Claims] 1. When constructing a girder between the mountain shelters facing each other in the girder girder construction method, the girder is bridged between the girders so that both ends of the girder are exposed to the girder. No, a jack means is provided between at least one end of the cut beam and the mountain stop wall facing the end, and the jack means is made to extend in the longitudinal direction of the cut beam. A method of erection of a girder in the girder mountain stop method. 2. A mechanism for adjusting the length of a cutting beam, the mechanism being inserted through at least one end face of the cutting beam,
A plurality of shaft members extending in the longitudinal direction of the beam and parallel to each other, and a contact plate attached to each shaft member portion located outside the end face and extending parallel to the end face, A fixing member for fixing the position of each of the shaft members with respect to the end face, and a mechanism for adjusting the length of a girder. 3. The shaft member is composed of a screw rod, a hole through which the screw rod is inserted is formed in the end face, and the fixing member is a nut screwed to the screw rod on both sides of the end face. The length adjusting mechanism for a beam as claimed in claim 2, wherein