JP2003206539A - Temporary closing construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an economical temporary closing construction method having a short construction period for driving a steel sheet pile in hard ground. <P>SOLUTION: This temporary closing construction method to be temporarily arranged in an outer peripheral part 1 of an objective structure, is characterized in that a plurality of master piles 2 are driven at prescribed intervals in the outer peripheral part 1, a waling material 31 is extended to the outer periphery of the driven master piles 2, the steel sheet pile 4 is also driven outside, and the steel sheet pile 4 is fixed to the waling material 31. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temporary cutoff method for constructing on hard ground or rock.

[0002]

2. Description of the Related Art Conventionally, in the case of constructing a structure underwater or at the water's edge, it is often the case that the work is temporarily performed by completely removing water from the parts required for the construction and making it a dry work. As this method, a temporary cutoff method is known. In addition, even for structures built on land, it is necessary to cut off the water in the earth retaining work when excavating below the groundwater level, and this is also used in this case. As described above, the temporary shut-off work mainly receives pressure such as water pressure and earth pressure from the outside. Therefore, the temporary shut-off work is required to have sufficient strength to withstand those pressures and also have a water stop function for keeping the inside of the construction work in a dry state. The temporary cutoff method is generally a method in which steel sheet pile b is driven into the ground to construct a continuous wall body and cut off. However, depending on the site, the ground where the steel sheet pile b is laid is hard ground or rock (hereinafter , Hard ground). In this case, conventionally, for example, a casing c is used in advance to drill a predetermined hard ground by a down-the-hole hammer method or the like, and then a steel sheet pile b is driven and supported on the hard ground. Thus, the steel sheet pile b which is self-supporting by the passive resistance from the ground propagates the water pressure received from the outside to the rooting portion due to the rigidity of the steel sheet pile b, and also has a sufficient depth so that Suppress flooding. Therefore, in the conventional temporary cutoff method for hard ground, it is necessary to drill holes in all places where the steel sheet pile b is set. However, the temporary cut-off work is often used only for temporary work, and generally, there is a trend to reduce the construction cost by setting a safety factor lower than that of this work.

[0003]

The above-mentioned conventional temporary cutoff method for the hard ground has the following problems. <a> Before placing a steel sheet pile on hard ground, it is necessary to drill a hole in the hard ground by the down-the-hole hammer method or the like. For this reason, it is necessary to drill holes in all the places where the steel sheet pile is placed, which is uneconomical because of the construction cost and construction period. <B> Only the steel sheet pile has the function of propagating the external force such as water pressure to the ground and resisting it. Therefore, changes in various constructions due to design changes due to changes in the situation at the site, etc., have a great impact because they change the type of steel sheet piles that are the main members, change the method of placing steel sheet piles, and the entire construction. .

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and in setting a steel sheet pile on a hard ground, pre-drilling points are minimized.
It is an object of the present invention to provide a temporary cutoff construction method that can shorten the construction period and the construction cost. In addition, it is an object of the present invention to provide a temporary shut-off method that can be economically changed while minimizing the effect on the change of members and the construction period even if the design has to be changed from the original schedule. The present invention achieves at least one of these objectives.

[0005]

In order to achieve the above object, the temporary cutoff method of the present invention is a temporary cutoff method for temporarily installing the outer periphery of a target structure, in which a plurality of parent piles are arranged at predetermined intervals. Is placed on the outer peripheral portion of the pile, and a reinforced member is bridged over the outer periphery of the driven parent pile, and a steel sheet pile is further driven outside, and the steel sheet pile is fixed to the reinforced member. To do.

Further, the temporary cutoff method of the present invention is characterized in that, in the temporary cutoff method described above, the front surface of the steel sheet pile is erected to construct a kettle, and the stored water that has permeated into the kettle is drained. I am trying.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

<B> Parent pile The parent pile 1 is a member that is driven into the ground to be self-supporting, and propagates the water pressure or the like received by the steel sheet piles 4 standing substantially parallel to the parent pile 1 to the ground. For this reason, the ground must be self-reliant, and must be installed with due consideration of the geology and the depth of driving into the ground, and resisting the passive earth pressure of earth and sand to ensure safety against falls and sliding. Try. Therefore, for example, in the case of the ground in which the hard ground layer 62 is deposited under the surface layer 61, the hard ground layer 62
Up to support. In addition, the main pile legs may be fixed by pouring concrete or the like to consolidate the soil, and it is not always necessary to consolidate the soil if the ground provides sufficient support. The method for driving the main pile 1 may be the down-the-hole hammer construction method alone, or may be a combination with another method,
There is no particular restriction.

The main piles 1 are laid on the outer periphery of the target structure at a predetermined interval, and this interval is determined by design.
For the parent pile 1, for example, an H steel pile or the like can be used. In this case, the material and shape are specified in JIS standard, and those having a width of 200 to 400 mm can be used. Since the cross-sectional performance of H steel piles differs depending on the direction, install in consideration of the direction in which horizontal force acts. A mooring material 32 can be projected on the main pile 1 toward the outside of the temporary cofferdam. The mooring member 32 is a member for mounting and fixing the uprising member 31 that bridges the main pile 2. The mooring members 32 are attached according to the number of steps of the bridging members 31 to be bridged.

<B> Uprising material The uprising material 31 is a member interposed between the transmission paths through which the steel pile 4 receives water pressure and the like and the parent pile 2 propagates to the ground. The uprising members 31 are arranged substantially orthogonal to the outside of the plurality of parent piles 2 standing upright at predetermined intervals. As a result, the surface pressure received by the steel sheet pile 4 is dispersed to the parent pile 2 via the reaping member 31,
The horizontal displacement of the steel sheet pile 4 can be reduced and the bending of the steel sheet pile 4 can be prevented. To fix the angry material 31,
It is mounted and fixed on the mooring material 32 which projects from the main pile 2. In addition, a steel sheet pile 4 that is cast further outward is erected by the material 3
It is fixed to 1 and integrated. This fixing method may be performed by welding or the like. A steel material such as an H-shaped steel can be used for the uprising material 31. Upholstering material 31 to parent pile 2
On the other hand, when the steel sheet pile 4 is bridged in one step, the steel sheet pile 4 is provided near the head. Moreover, you may provide the uprising material 31 in several steps as needed.

<C> Steel sheet pile The steel sheet pile 4 is a structural member that is continuously erected around the target structure and directly receives pressure such as water pressure from the outside and has sufficient strength to withstand the pressure. At the same time, a structure with a water stop function to keep the inside of the construction dry is provided. In addition to the hydrostatic pressure, the steel sheet pile 4 may have a flowing water pressure,
Since it may be subject to dynamic external forces such as wave pressure, the structure must be designed with due consideration to these effects. Note that the steel sheet pile 4 does not necessarily need to surround the entire outer periphery of the target structure, and a part of the steel sheet pile 4 may use a quay wall, a sea wall, or the like. The steel sheet pile 4 has a U shape, a linear shape, a steel pipe shape, or the like, but a material having an arbitrary cross-sectional performance can be selected depending on the use. The steel sheet pile 4 is supported by the uprising member 31 on the upper side and the ground on the lower side. By supporting the steel sheet pile 4 on the ground, it is sufficient that the steel sheet pile 4 can be prevented from tipping or sliding due to water pressure and earth pressure acting from the outside, and the water can be stopped, and in particular, the force need not be transmitted to the ground. Therefore, for example, the depth at which the vibration driving machine can be driven, that is, the driving depth may be only the surface layer 6, and the hard ground layer 62.
You don't have to type until. In addition, it is necessary to provide a water blocking structure between the steel sheet piles 4. Therefore, for example, an elastic material such as a swelling water blocking material or a water blocking rubber of the steel sheet pile 4 can be filled in the play of the engaging portion of the steel sheet pile 4 joint to stop water.

<D> Kamaba Kamaba 5 is constructed by constructing a dike in front of the steel sheet pile 4, which is the bottom of the excavated well, and excavating a groove therebetween (see FIG. 1). The kettle 5 is constructed in the vicinity of the steel sheet pile 4, because the permeation flow and the flow velocity are particularly large, and the permeated water is prevented from flowing into the excavation interior. This is constructed substantially parallel to the steel sheet pile 4, and does not necessarily have to be constructed on the entire circumference. Further, the kettle 5 may be protected by a wood sheet pile wall or the like. A water collection place leading from the kettle 5 may be separately constructed at a deep place from the bottom of the excavation. This is because the permeated water is naturally guided to the water collecting place via the cauldron 5 and then discharged to the outside by a submersible pump or a fugal pump. The pump used for discharging may vary depending on the size of the water collecting place and the water permeability of the ground, but for example, a submersible pump having a discharge outlet diameter of 2 inches which is generally easy to carry may be used.

<E> Other In general, when driving the steel sheet pile 4, in order to drive the steel sheet pile 4 correctly on the planned line and to ensure stability during construction, a guide frame made of a conductive material and a conductive pile is provided. Can be used as a guide when placing the steel pipe casing (not shown).
The guide pile is laid substantially parallel to the main pile 2, and the conductive material is built on the guide pile. A steel sheet pile 4 is provided with a wedge etc. at the beginning of driving.
Can be further fixed. The guide frame may be sequentially removed from the place where the driving is finished and used repeatedly.

In addition to this, along with excavation inside the temporary cut-off work, it is also possible to temporarily install a cut-off on the facing main pile 2 inside the excavation to support water pressure from the surroundings (not shown). In addition, a fire striking material may be provided at the corner of the temporary cut-off work, and if the cutting is long, an intermediate pile may be provided to fix the cutting and prevent buckling of the cutting.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the temporary cut-off method of the present invention will be described below with reference to the drawings. It should be noted that although this embodiment describes a temporary closing method in water, it can also be used as a temporary closing method using earth retaining or as the main work.

<A> Preparation for driving the main pile (see FIG. 1) When driving the steel sheet pile 4 on the water or near the waterfront, it is decided whether to land, ship, or scaffold, and Arrange for various work vessels. Next, guide piles are set in the river (not shown). The penetration depth of the guide pile may be a depth that can be penetrated using a vibration driving machine. The guide material is laid over the driven piles that have been placed, and the guide frame is installed by temporarily fixing it.

<B> Placing the main pile A steel pipe casing is placed in the space between the guide frames temporarily provided in the above step. The steel pipe casing may be driven by using the driving method depending on the hardness of the ground. For example, when the ground fault is composed of the surface layer 61 of soft ground and the hard ground layer 62 deposited thereunder, the driving to the surface layer 61 part is performed by a vibration driving machine, and the down ground hole hammer is applied to the hard ground layer 62. It may be placed by a construction method or the like. At this time, fine particles of excavated soil are suspended with bentonite muddy water due to the driving and drilling of the steel pipe casing, and the slime generated at the bottom of the hole is removed. After checking the depth of the bottom of the hole, use a plunger or the like to place fresh concrete. After pulling out the steel pipe casing, the parent pile 2 is transported by a crane or the like to build the parent pile 2. The support structure of the main pile 2 on the ground does not always need to be consolidated according to various conditions such as the site and the ground.

<C> Fixing of the upholstery member The mooring member 32 is extended from the main pile 2 built in the predetermined position. The mooring member 32 may be attached first if there is no hindrance during transportation or installation of the main pile 2. The mooring member 32 is attached to the outer side surface of the main pile 2 to be laid. The uprising member 31 is placed on the upper part of the mooring member 32 and fixed to the mooring member 32.

<D> Placing of Steel Sheet Pile After laying up the upholstery material 31 on the outside of the side surface of the main pile 2, steel sheet pile 4 is sequentially laid in the ground (see FIG. 2). For this placement,
For example, it can be set using a vibration driving machine,
The driving depth may be such that the steel sheet pile 4 does not fall or slide, and may be the depth up to the surface layer 61, for example. Further, the temporary shut-off work may be provided with a fired material or a burial inside if necessary. After the steel sheet pile 4 is driven in, water is stopped by filling the play space of the engaging portion of the steel sheet pile 4 joint. The upper part of the steel sheet pile 4 is fixed to the uprising member 31.

<E> Excavation inside the well The inside of the well which is temporarily installed on the outer peripheral portion 1 of the structure to be excavated is drained by an appropriate method, and a cut beam is temporarily installed if necessary. In the case of temporarily installing the cut-outs, the brackets are arranged on the inner surface of the main pile 2 at intervals. Then, the water surface sequentially descends due to the drainage, and each of the facing brackets that appears on the water surface due to this drainage is provided with a cutting beam. Moreover, you may install a fired material and an intermediate pile as needed. After draining the inside of the well, the embankment 5 is constructed on the front side of the steel sheet pile 4 at the bottom of the excavation, if necessary (see FIG. 1). This is to stop the inflow of permeated water that may enter from the lower part of the steel sheet pile 4. Thus, the inside of the temporary cut-off work is maintained as a dry work, and the target structure is constructed.

[0021]

Since the temporary shutoff method of the present invention is as described above, the following effects can be obtained. <A> In the structure of the present invention, the main pile receives water pressure and the like, and the steel sheet pile is used to stop water. For this reason, since only the place where the parent pile is to be drilled is required for drilling the hard ground, the construction cost is reduced and the construction period is shortened, which is very economical. Furthermore, since it is a construction method that mainly relies on the main piles for resistance to water pressure, there is no need to consider the rigidity of propagating water pressure, etc. to the ground and the rigidity due to ground deformation for steel sheet piles. It is economical because the cross-sectional performance of can be set lower than before. <B> Further, the function of receiving a horizontal force such as water pressure and the function of transmitting the force to the supporting ground are constituted by different members. Therefore, even if a design change is forced, only a part of the change does not have to be applied to the whole, and thus the loss is small.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a temporary cutoff method according to the present invention.

FIG. 2 is a perspective view of a temporary cutoff method according to the present invention.

FIG. 3 is an explanatory plan view of a temporary cutoff method according to the present invention.

FIG. 4 is an explanatory plan view of a conventional temporary cutoff method.

[Explanation of symbols]

1 ... Outer peripheral part 2 ... Parent pile 31 .. Uprising material 4 ... Steel sheet pile 51 ... Kamaba

Claims (2)

[Claims] 1. A temporary cut-off method for temporarily installing an outer periphery of a target structure, wherein a plurality of parent piles are driven at the outer periphery at a predetermined interval, and the piled up parent piles are angulated. A temporary cut-off construction method, characterized in that a material is bridged, a steel sheet pile is further cast on the outer side, and the steel sheet pile is fixedly mounted on the waving material. 2. The temporary cutoff method according to claim 1, wherein a front wall of the steel sheet pile is erected to construct a kettle, and water stored in the kettle is drained. .