JPH056601B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for constructing a pile-type precast concrete breakwater or breakwater.

Prior art A wave dissipating means is formed by randomly throwing multiple concrete blocks of irregular shape into the seashore or into the sea, or a concrete structure is constructed in the sea or on the shore to counter wave energy using gravity. Breakwaters have been known for a long time, but they all have problems such as the suitability of the construction method for the topography and ground, the difficulty of underwater work, the input of a huge amount of materials, and the long construction period, making them economically disadvantageous. be.

Purpose The present invention aims to eliminate the drawbacks of the above-mentioned conventional construction methods, and by adopting the underwater concrete construction method, which has been developed in recent years, by progressively improving it, it can be constructed using relatively small amounts of materials and labor. The aim is to shorten the construction period, make it possible to construct an economically solid breakwater, and provide a method that is highly adaptable to environmental and construction conditions.

Structure The method of the present invention includes: (1) a step of driving at least two or more pairs of steel pipe piles facing each other at a predetermined interval at a predetermined position on the water bottom; A guide member of a precast concrete block board in which a plurality of short outer pipes are fixed at predetermined intervals and arranged in the same direction along the width surface is lifted vertically, and the short outer pipe portions are fixed to the of steel pipe piles,
A step of temporarily fixing one of the guide members along each steel pipe pile by suspending the pipes so as to be inserted through the top ends of the respective steel pipe piles; The process of erecting and temporarily fixing braces between the pipes, and injecting and solidifying filler into the gaps between the short pipe for extrapolation and the steel pipe pile and between the braces to form the point part and the structure framework. A step of dropping a plate-shaped precast concrete block plate with no holes or with through holes between the guide grooves of a pair of parallel H-shaped cross-section members formed as a result of the above step. , a step of supporting both ends by the guide groove, and a step of stacking the concrete block plates over the entire length of the guide groove by repeating the step to form a concrete block wall. Construction method.

(2) The precast concrete block structure described in paragraph (1) above consists of forming a pair of a wave-dissipating concrete block wall with through holes and a non-porous wave-breaking concrete block wall. How to construct a breakwater or breakwater.

(3) A process of driving at least two or more pairs of steel pipe piles facing each other at a predetermined interval at required positions on the water bottom, and in parallel with the above process, a pair of guide members made of H-shaped sections A step of fixing a connecting brace or beam between the short outer pipes to form a guide member structure framework, lifting the framework vertically, and attaching the pair of cast steel pipes to the short outer pipes. The breakwater according to paragraph (1) or paragraph (2), which comprises suspending the piles by inserting the top ends of each pile, and inserting and temporarily fixing the framework along a pair of steel pipe piles. How to construct a wave-dissipating levee.

The embodiment will now be described with reference to the drawings.

Example 1 Figure 1 shows the cross-sectional structure of a precast concrete breakwater formed by implementing the construction method of the present invention, and Figure 2 is a cross-sectional view taken along the - line in Figure 1. , In the figure, 1 is a pair of steel pipe piles driven into the seabed, which are installed in the direction of wave propagation or in the direction perpendicular to the coast. The distance between the pair of steel pipe piles is unified to a predetermined length, and both piles are driven parallel to each other.

2 is a short pipe for extrapolation (hereinafter referred to as outer pipe) which has a diameter one size larger than the diameter of the steel pipe pile 1 and is short in length.
In principle, the brace 3 or the brace attachment part 4 is fixed to the side surface of the tube. Each of the outer pipes 2 is inserted into the steel pipe pile 1 from its top end, while an H-shaped cross-section member 5 is juxtaposed to the pipe pile 1 and has a length approximately equal to the substantial height of the embankment.
(hereinafter referred to as H-shaped member), a plurality of them are fixed to the side surface (width side) at intervals in the longitudinal direction and aligned in the same direction. The above-mentioned assembly of the outer tube 2 and the H-shaped member 5 is carried out at a processing plant on land where the equipment has been prepared in advance. As shown in FIG. 1, the two are in opposite positions. In addition, as shown in FIG. 2, which shows a cross-section taken along the line in the figure, the relationship between the H-shaped member 5 and the outer tube 2 is such that the width of the H-shaped member 5 is perpendicular to the opening direction of the guide groove 6 of the member 5. Outer tube 2
are combined. The section 5 is usually made of H-beam steel, and is connected to the outer tube 2 by welding, riveting, bolts and nuts, or other fixing means. In this way, the guide members of the block are preformed in a processing shop remote from the construction site.

7 is injected into the gap between the outer pipe 2 and the steel pipe pile 1.
A solidified filler, generally expanded mortar, is used to bond between the pile and the outer tube, between the outer tube and the brace, and to form a point in the steel pipe pile.

_8-1 and _8-2 are precast concrete blocks, the width l is the pitch p between a pair of steel pipe piles and the adjacent steel pipe pile, and the thickness s is the same as that of the H-shaped member 5. The height h, which is approximately equal to the groove width, can be set arbitrarily depending on the shape of the block, but at least if a plurality of wave-dissipating holes 9 passing through the block from the front and back are provided, the strength will be extremely reduced. It won't happen.

Figures 3a and 3b are front views of the blocks, in which figure a is the wave-dissipating block _8-1 , which is provided with a plurality of wave-dissipating holes 9 passing through it, and figure b is the wave-dissipating block _8-2. shows.

Referring again to FIGS. 1 and 2, the concrete blocks 8 _-1 and 8 _-2 are connected to the opposing guide grooves 6 of the H-shaped members 5 of the guide members installed in parallel and fixed to the adjacent steel pipe piles, respectively. , 6, guide both ends of it.
The lower surface of the pile is supported on the seabed surface and placed horizontally between adjacent steel pipe piles. If necessary, stones or stacked stones 11 may be placed on the seabed surface to prevent scouring by offshore waves and to close the gap between the bottom of the block and the seabed surface. The precast concrete block plates are all made of the same shape and the same materials, and are produced in large quantities on land away from the construction site prior to construction, and are used to guide the grooves 6, 6 provided in the H-shaped member of the guide member. By repeatedly stacking multiple pieces in parallel, a wave-dissipating wall or wave-breaking wall with one surface is formed. In the figure, _8-1 is a wave-dissipating block with a wave-dissipating hole 9 inserted through the concrete block. When waves pass through multiple through holes drilled in the wave-dissipating wall,
Consume and absorb that energy.

_8-2 is a breakwater block, which is fitted into the H-shaped member of the guide member installed parallel to the pile located on the shore side of a pair of steel pipe piles, and is stacked to form a breakwater wall. This weakens the wave energy and completely blocks it out, making it an effective breakwater overall.

The braces that connect the diagonals of the framework are installed to apply tensile stress to the strain that occurs in the structural members, including the steel pipe piles, that are subjected to wave pressure.

10 is a slab laid on the top of the breakwater, 1
2 is the upper concrete with wave-receiving function, W,
L is the water line. In this embodiment, as part of the work to protect the legs of the embankment, concrete is placed on the stacked stones 11 and on the seabed nearby.

The above-mentioned wave-dissipating levee or breakwater can be constructed by the method described below, so the water depth is 10 to 20 meters.
There are the following advantages regarding construction on the seabed.

(1) Compared to conventional construction methods, the construction period can be shortened by 20-30% because the parts used are more prefabricated and construction on site is easier.

(2) The use of fewer materials, smaller size, and lighter weight make it easier to transport materials, and the construction machinery can be made smaller.

(3) It can be constructed even on soft ground without ground improvement work, and since the breakwater body is supported by steel pipe piles 1, there is no concern about subsidence as seen with other gravity type breakwaters.

(4) By using underwater member joining (underwater point construction method), it is possible to form an economical cross section that is easy to construct and has high rigidity.

(5) It can be applied (constructed) even when the seabed surface is immovable.

There are some that have excellent economic effects.

Construction method While measuring the driving position and verticality of the steel pipe pile 1 by sighting and distance measurement from two directions on land, drive each steel pipe pile 1, and place a pair of steel pipe piles with a predetermined distance apart horizontally by p. Pour at least one set at a distance. The allowable range of the length of the predetermined interval must not exceed the difference in diameter between the steel pipe pile 1 and the outer pipe 2 when the framework of the guide member is already completed. The steel pipe pile after driving is at the water surface W, L,
After adjusting the height from the top, one guide member is lifted to each steel pipe pile, and the steel pipe piles of all the outer pipes 2 fixed to the same member are hung one after another from the top of the steel pipe pile, and then the H-shaped member 5 of the guide member is hammered into place. The installed steel pipe piles 1 are temporarily fixed so that they are juxtaposed, and the outer pipes 2 suspended from the pair of steel pipe piles 1 are temporarily connected using braces 3, and the outer pipes 2 and the steel pipe piles are 1 or between the brace mounting member 4 and the brace 3, a fluid filler is injected and solidified to firmly connect each member and form a framework structure. In this case, it is necessary to provide sealing means on the bottom side of each gap to prevent the fluid filler from leaking out from the gap between the two before solidifying. In the framework structure assembled by the above-mentioned process, the H-shaped members 5 are arranged on the outside of the steel pipe piles, and the grooves 6 are oriented perpendicular to the frame surface. In addition, the braces 3 on the diagonal of the framework are connected on the offshore side near the seabed and on the shore side to the top point, so that when wave pressure is applied to the framework, the diagonal braces 3 (not pressure).

As shown in FIG. 2, the framework structures as described above are arranged in at least one set of identical structures separated by a pitch p in the lateral direction. Vertical guide grooves 6, 6 provided in a pair of guide members thus constructed and facing each other with an interval of approximately p
In between, the length l between the guide grooves 6 and 6, the thickness s that matches the width of the groove 6, and the appropriate amount are prepared in large quantities at a processing factory on land. Concrete block plates 8 _-1 and 8 _-2 shown in the third diagram having a height h of
It is inserted into the vessel, lowered horizontally into the sea, and placed horizontally on the ocean floor.

Before starting the above process, if necessary, concrete is placed on the seabed near the structure or stacked stones 11 are placed in order to reinforce the seabed of the steel pipe pile legs against washing by waves. The foundation structure constructed in this way functions to support the bottom of the concrete block plates that will be piled up from now on, but the support of the bottom of the blocks is achieved by providing a stopper at the lower end of the groove 6 of the H-shaped member. Therefore, they are replaceable. and,
If this latter method is adopted, by fixing guide members of a certain length to all the steel pipe piles 1, it is possible to always arrange the concrete block plates horizontally regardless of the seabed topography. Become.

After that, the above process is repeated on each concrete block board 8.
_-1 , 8 By repeating _-2 , concrete blocks are stacked up to the same height as the guide member between a set of steel pipe piles, and a block wall is constructed on both sides supported by H-shaped members. can be formed. In this case, it is desirable to use the wave-dissipating block _8-1 for the block wall facing offshore, and the wave-breaking block _8-2 for constructing the shore-side block wall. After assembling the double block wall to the steel pipe pile 1, a brace 3 horizontally connects the top end of the pile, and a slab 10 is stretched and fixed on the top surface of the top beam to form a floor. Accordingly, the construction of the breakwater structure is completed by placing the upper concrete 12 which functions as a breakwater shelf thereon.

In addition, the double block wall is breakwater block _8-2 .
It is also free to construct it with only the wave-dissipating block _8-1 .

Example 2 In the construction method described in Example 1, steel pipes were used in principle for the diagonally arranged members of the braces 3 forming the framework of the guide member, but a telescopic joint was applied here. A construction method in which the steel rods are engaged with a sash, the space between the steel pipe pile 1 and the outer pipe 2 is solidified with a filler material 7, and after the case point is formed, initial stress is generated in the framework by adjusting each expansion joint. can also be adopted. The other procedures are the same as those described in Example 1, and will therefore be omitted.

Example 3 Examples 1 and 2 were aimed at relatively large-scale breakwaters or breakwaters built in places with deep water or on coasts where waves are strong, but in the case of small-scale breakwaters, It can be constructed by a method similar to this example. That is, in Example 1, the cast steel pipe pile 1, the concrete block 8 _-1 ,
_8-2 , concrete block guide member framework excluding slab 10, etc., in other words, outer pipe 2, brace 3,
A framework consisting of the brace mounting part 4 and the H-shaped member 5 is pre-assembled integrally at a suitable location on land before construction.

As described in Example 1, the steps of positioning the steel pipe pile 1 on the sea, measuring it after it is vertical, driving at least a pair of pipe piles, and setting the height of the pipe piles are the same steps, but after that, the steps described above are carried out. In parallel with the process, the block guide member framework that has been integrally assembled and processed on land is transported to the sea and hoisted, and each outer pipe 2 is fixed to the hanging framework at a pair of pipe pile positions.
A guide member framework is installed so as to be inserted into the top end of each pipe pile 1 and juxtaposed between the pair of steel pipe piles, and is temporarily fixed. After sealing the bottom of the gap between the pipe pile 1 and the outer pipe 2, the pipe pile and the framework are fixed by injecting and solidifying a fluid filler into all the gaps. The subsequent steps are the same as those described in Example 1, so they will not be explained again.

As can be seen from the above, this method allows the framework to be constructed on land where the equipment and environment are well-prepared. Since the framework can be formed in parallel with the offshore pouring work described in step 1, the construction period on site can be significantly shortened. The only problem is the framework.
Because it is pre-formed into a one-piece structure, it becomes large and difficult to transport, but by selecting a processing location that will mainly be transported on water,
Avoiding the difficulties of transporting over land
It is not hard. In addition, since the left and right intervals of the outer pipes 2, 2 are fixed, the steel pipe pile 1 to be driven through the outer pipes 2, 2 is fixed.
It is unavoidable that the tolerance range for the relative position of and the perpendicularity thereof becomes strict. The above-mentioned technical difficulty can be alleviated to some extent by increasing the difference in diameter between the pipe pile 1 and the outer pipe 2.

Effects As described above, when using the construction method of the present invention, (1) a highly rigid frame structure is constructed in which the steel pipe piles are connected with each other with braces through the grid points, so the number of piles can be reduced overall; It is possible to reduce the amount of materials used, such as by reducing the pile diameter.

(2) The length of the extrapolation short tube that forms the case point can be shortened, reducing the amount of steel used and improving economic efficiency.

(3) Since parts can be prefabricated, processes can be performed in parallel and the construction period can be significantly shortened, which shortens and simplifies the construction period on water where footing is poor.

(4) Large structures are constructed by combining relatively small members.

(5) Construct large structures using small construction machinery comparable to the pile method.

There are significant economic effects.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of a breakwater constructed by carrying out the method of the present invention, and FIG. 2 is a cross-sectional view of an embodiment of the breakwater constructed by implementing the method of the present invention. 3 is a front view of a precast concrete plate that is one of the components of the breakwater, and figure a shows the wave-dissipating block,
Part b is a breakwater block. 1...Steel pipe pile, 2...Short pipe for extrapolation (outer pipe), 3
...Brace, 4...Brace material attachment part, 5...
Cross-section H-shaped member, 6...Groove, 7...Filling material, 8 _-1 ,
_8-2 ...Precast concrete block board,
9...Wave dissipating through hole, 10...Slab, 11...
Stacked stones.

Claims (1)

[Claims] 1. A process of driving at least two or more pairs of steel pipe piles facing each other at predetermined intervals at predetermined positions on the bottom of the water, using elongated piles with an H-shaped cross section, with predetermined spacing in the longitudinal direction. A guide member made of a precast concrete block plate with a plurality of short outer pipes fixed in the same direction along the width is lifted vertically,
A step of suspending the short pipe portion for extrapolation so as to pass through the top end of each of the steel pipe piles, and temporarily fixing the guide member by inserting it along each steel pipe pile;
A step of erecting and temporarily fixing a brace between each of the short outer pipes of a pair of guide members occupying corresponding positions based on the above process, and a gap between the short outer pipe and the steel pipe pile and between the braces. A step of injecting and solidifying a filler into the structure to form a point part and a structure framework; A process of dropping a plate-shaped precast concrete block plate with a hole or a through hole and supporting both ends of the plate by the guide groove, and repeating the process allows the concrete block plates to be stacked over the entire length of the guide groove to create concrete. A method for constructing a breakwater or wave-dissipating levee, characterized by comprising the step of forming a block wall. 2. Precast concrete block construction consists of forming a pair of a wave-dissipating concrete block wall with through holes and a non-porous wave-breaking concrete block wall. Claim 1
Method of constructing a breakwater or wave-dissipating levee as described in Section 1. 3. The process of driving at least two or more pairs of steel pipe piles facing each other at a predetermined interval at a required position on the water bottom;
In parallel with the above step, a step of connecting the corresponding short tubes for outer insertion of a pair of guide members made of H-shaped cross-section members and fixing braces or beams to form a guide member structure framework; Lift vertically,
A patent claim comprising the step of suspending the pair of driven steel pipe piles by inserting their respective top ends into the short pipe for extrapolation, and temporarily fixing the framework by inserting the framework along the pair of steel pipe piles. A method for constructing a breakwater or wave-dissipating levee according to item 1 or 2.