JPS5923797Y2 - Piles for driving into bedrock - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of a pile for driving into rock, and more specifically, a pile for driving into rock that has an improved nozzle that ejects fluid to remove crushed rock by driving the pile into bedrock. It is related to.

Until now, it was thought that it was impossible to drive piles directly into bedrock containing hard soil with an N value (standard penetration test value) of 50 or higher, but recently it has become possible to drive piles directly into bedrock as described above. A construction method was developed.

This construction method utilizes the pile body as a transmitter of impact energy to the rock mass, and crushes the rock mass by directly impacting the rock mass with the tip of the pile body.The crushed rock is then pumped through a nozzle placed near the tip of the pile body with a fluid, e.g. By injecting water and displacing the crushed rock at the impact point, the impact energy that is always concentrated at the tip of the pile body is transmitted to the rock in the most efficient manner, thereby crushing the rock.

Therefore, since the pile body can be easily driven into bedrock, it is a useful construction method with a wide range of applications, especially in offshore construction.

However, since the nozzle must blow away the crushed rock, it must always be located near the tip of the pile body.

Therefore, the above-mentioned effect cannot be achieved unless the nozzle is also driven into the rock as the pile body is driven into the rock.

That is, the tip of the nozzle must also hit the rock to break it.

However, in conventional nozzles of this type, the fluid injection port is located on the nozzle tip surface, so if this tip is damaged when the nozzle tip hits rock, the shape of the fluid injection port may be deformed. There is a risk that the amount and direction of the fluid ejected will change, making it impossible to achieve the intended purpose.

Therefore, an object of the present invention is to provide a rock piling machine that prevents the injection port from being deformed for a long time even when the tip of the nozzle hits the rock bed by improving the conventional nozzle described above.

To achieve this purpose, the present invention consists of a pile body driven by a vibrating pile driver and a water guide pipe, and the water guide pipe is movable vertically relative to the pile body and is attached to the pile body. This is a pile for driving into rock, which is attached along the water guide pipe and has a rock striking piece projected forward from the nozzle at the tip of the water guide pipe from its injection port.

Next, embodiments of the present invention will be described with reference to the drawings.

A vibrating pile driver, e.g.
A fluorohammer is suspended.

As shown in FIG. 1, this vibrohammer is equipped with a pile body 1 to be driven into bedrock so as to transmit vibrations generated by the vibrohammer.

This pile body 1 preferably has a number of water guide pipes 2 along its inner edge that correspond to the size of the pile, that is, the amount of crushed rock to be removed, and the tip thereof is connected to the bedrock of the pile body 1. It is located near the point of impact.

The water guide pipe 2 is disposed so as to be freely movable relative to the pile body 1, for example, in the vertical direction and, if necessary, in the horizontal direction.

The water guide pipe 2 is connected to, for example, a high water pressure pump so that a nozzle 4 at its tip injects water at a pressure and amount capable of removing crushed rock from the impact point of the pile body 1.

To explain the relationship between the water guide pipe 2 and the pile main body 1 mentioned above, in Fig. 1, when the pile main body 1 is made of H-shaped steel, the steady rest hardware 3 is fixed to the corner part of the web 1a and the flange 1b. Then, the water guide pipe 2 is loosely fitted into the gap formed between the steady rest hardware 3, the web 1a, and the flange 1b.

The water guide pipe 2 is connected to the pile main body 1 with a certain amount of clearance above it by a hanging hardware 5 such as a wire or a chino.

In addition, when arranging the water guide pipe 2 on the pile body 1,
When the pile main body 1 is a steel pipe, for example, when two water guide pipes 2 are used, steady rest metal fittings are installed at two opposite locations along the inner edge of the steel pipe, and the steady rest is attached to the inner edge of the steel pipe and the steady rest. The water guide pipe may be loosely fitted into each gap formed by the metal fittings.

On the other hand, the nozzle 4 has a connecting portion 4a with the water guide pipe 2, as shown in FIG. 2, and an injection hole 4b is bored from the connecting portion 4a toward the tip.

Moreover, from the outer peripheral part of the injection port 4C of the injection hole 4b,
A rock striking piece 4d extends forward.

This rock striking piece 4d has a jet nozzle 4C as shown in FIG.
Alternatively, as shown in FIG. 3, the outer periphery of the injection port 4C may be covered with multiple rock striking pieces 4d.

In addition, when the rock striking pieces 4d are covered in multiple layers as shown in FIG. 3, it is better to make the protruding length of each rock striking piece 4d longer as it is located outward, so that the tip of the rock striking piece 4d is covered with multiple layers. This is preferable in terms of concentrating the impact force, and the jetting angle of the water spouted from the jetting port 4C can be easily set to a desired angle.

Now, when driving the pile body 1 into the bedrock, the bedrock on the seabed is sloped and uneven, and is affected by ocean currents, so if the pile body 1 cannot stand on its own, temporary scaffolding will be erected, and high pressure will be applied to the pile body 1 on board the ship. Attach the water guide pipe 2 with hanging hardware.

Next, after starting a high water pressure pump (not shown) and inspecting the nozzle 4, the pile body 1 is erected and a vibrohammer (vibrating pile driver) is attached to the end of the pile body 1.

In this state, the high water pressure pump is started, the vibrohammer is started, and the pile body 1 is driven.

During this driving, vibrations caused by the vibrohammer are transmitted to the pile body 1, so that the tip of the pile body 1 hits the bedrock.

As a result of this blow, the tip of the pile body 1 shatters the struck portion of the bedrock, and the pile body 1 is separated from the bedrock due to the reaction force.

At this time, the nozzle 4 of the water guide pipe 2 strikes the bedrock later than the pile body 1, and then the hanging hardware 5 tightens as the pile body 1 separates from the bedrock until the water guide pipe 2 is pulled up. During this time, the rock remaining near the impact point and crushed at the point of impact is removed by the water flow.

The nozzle 4 strikes the rock slab as described above, and at this time, it is the tip of the rock striking piece 4d of the nozzle 4 that hits the rock slab.

Therefore, even if the tip of the rock striking piece 4d is damaged, the injection port 4C is not affected in any way, so that the water flow for removing the crushed rock has the desired effect.

In addition, when the nozzle 4 is as shown in FIG. 3, it is the outer rock striking piece 4d that strikes the rock slab first.

When the outer rock striking piece 4d is damaged and its protrusion length becomes short, the inner rock striking piece 4d will strike the rock, so the striking force is always concentrated on the rock striking piece 4d to generate the necessary striking force. It is possible to extend the service life of the nozzle 4 while obtaining the desired results.

As described above, the nozzle 4 that has struck the bedrock and removed the crushed rock is separated from the bedrock via the water guide pipe 2 and the hanging hardware 5 due to the separation of the pile body 1 from the bedrock. At this time, the pile main body 1 has started moving in the direction of the rock wall for impact, so when the pile main body 1 hits the rock wall, the nozzle 4 is located at a distance from the rock wall. Become.

Therefore, the action of the jetted water on the bedrock is weakened, and during this time the pile body 1 hits the bedrock, so that the energy of the pile body 1 is not reduced by the jetted water when the pile body 1 is struck.

In this way, while the pile main body 1 and the nozzle 4 move up and down alternately, the nozzle 4 also hits the bedrock and perforates it, and the pile body 1 and the nozzle 4 bite into the bedrock as shown in Fig. 1. Even if the main body 1 is driven into a bedrock and the rock striking piece 4d of the nozzle 4 is damaged to some extent, the nozzle 4 still functions in the same manner as described above.

In addition, the position of the steady rest hardware 3 is such that the nozzle 4 is placed close to the hanging hardware 5 in order to stabilize the horizontal position of the water guide pipe 2.
It is best to place it as low as possible within the range where it can move up and down.

In this case, when the pile body 1 and the nozzle 4 are driven into the bedrock and the steady rest hardware 3 collides with the rock, the steady rest hardware 3 is attached to the pile body 1 to such an extent that the steady rest hardware 3 can be removed by the impact force. After this is removed, the nozzle 4 is guided by the bedrock, so there is no problem with the work.

As described above, according to the present invention, since the injection port can be protected by providing the rock striking piece in the nozzle, the desired fluid can be obtained even if the rock striking piece is damaged to some extent.

Therefore, the pile main body can be driven into the rock while the service life of the nozzle is greatly extended compared to conventional nozzles.

Since the water guide pipe 2 is movable vertically with respect to the pile body 1 and is attached along the pile body, the pile body 1 is driven against the rock by the vibrating pile driver and rebounds, causing it to bounce up. At the same time, the rock hitting piece 4d protruding forward from the nozzle 4 of the water guide pipe 2 hits the rock, and at the same time, the water jetted from the nozzle 4 splashes the crushed rock that has been mainly crushed by the impact of the pile body 1. Then, the water guide pipe 2 rebounds with a delay from the repulsion of the pile body 1 due to the reverse jet force of the jetted water and jumps up, and at this time the pile body 1 falls for the next blow and hits the bedrock again. Similarly, the pile body 1 and the water guide pipe 2 alternately move up and down, and the pile can be easily driven into bedrock with an N value of 50 or more.

Furthermore, since the pile main body 1 and the water guide pipe 2 move up and down alternately as described above, the reverse jetting force of the water injected from the water guide pipe 2 does not directly act on the pile main body, and the jet water Since the crushed rock is removed, it is possible to prevent the so-called "sand cushion" in which the crushed rock acts like a cushion against the pile driving force of the pile body 1, and furthermore, it is possible to prevent the water guide pipe from running along the pile body. Since it is attached, it is possible to prevent the water guide pipe from shaking as much as possible when water is injected.

In addition, since the jetted water only needs to have enough water pressure and volume to remove crushed rocks, the water pressure and volume can be minimized.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a striking part showing one embodiment of the present invention, Fig. 2 is a partially sectional perspective view of a nozzle, and Fig. 3 is a partially sectional perspective view showing another embodiment of the nozzle. It is. 1... Pile body, 4... Nozzle, 4C.
...Injection port, 4d...Bedrock impact piece, D.
·····bedrock.

Claims (1)

[Scope of utility model registration request] It consists of a pile body driven by a vibrating pile driver and a water guide pipe, and the water guide pipe is movable vertically relative to the pile body and is attached along the pile body. A pile for driving into rock, characterized in that a tip nozzle has a rock-driving piece projected forward from its injection port.