JPS60159218A - Sound-insulator for pile hammer - Google Patents

Abstract

PURPOSE:To improve working efficiency, by a method wherein a surrounding part, which is formed by a resilient material and formed in the shape of bellows, is located around a pile, a space between the pile and the surrounding part is filled with liquid, and gas is mixedly present in the liquid. CONSTITUTION:Sound insulating cylinders 9 and 9a, which is formed by a resilient material and is formed in the shape of bellows, are secured around a pile 2, and the sound-insulating cylinders are lifted and disposed in a position togetherwith a pile hammer 1. Thereafter, after, with a pump 5-1 driven, water is poured in the sound insulating cylinder 9a side through a water inlet hole 6, the pile 2 is driven through the working of the hammer 1. Simultaneously, with an air compressor 10 driven, an air 11 is sucked in water around the sound insulating cylinder 9. This causes vibration, produced along with driving of the pile 2, to be absorbed and damped by means of the sound insulating cylinders 9 and 9a, and causes damping of water hammer by dint of air bubbles.

Description

[Detailed description of the invention] The present invention relates to improving the fatigue of a sound insulation device for a pile hammer.

When a hydraulic or diesel engine type foundation pile driver (hereinafter referred to as a pile hammer) is used, it makes a big noise and spreads the noise to the surrounding area, causing a major pollution problem.

Conventionally, in order to prevent this noise, a D sound part 3 as shown in FIG. 1 has been used, but this sound insulation part 3 has the following drawbacks.

(1) It is very heavy.

(2) It is not easy to assemble (it takes 1 hour).

(3) Production cost is extremely high.

(4) It is not easy to transport.

In general, the noise generated during pile driving is mainly the exhaust gas discharge sound, the ram falling impact sound, and the fundamental sound of the hammer 1 and the pile 2 in the case of a diesel pile hammer, whereas in the case of a hydraulic pile hammer In the case of a hammer, this is the impact sound between the pile hammer 1 and the pile 2. however,
The noise of these striking parts is radiated not only from the striking parts to the surroundings (but also from the entire surface of the pile).

In particular, steel pipe piles produce higher noise than concrete piles when they resonate with the impact sound. Therefore, as mentioned above, it is necessary to insulate the entire pile including the pile hammer 1 from sound.

Piles are generally 30 to 40 meters long and 50 to 100 meters in diameter.
00α, and it is not easy to surround such a large thing with a metal sound insulating tube 3. on the other hand,
Generally speaking, when the noise from pile 2 becomes louder, it is not when pile 2 is sinking, but when pile 2 has sunk by +h, and at this time, empirically, the pile is almost close to the ground. It's also when Hammer 1 is coming down. Further, the time required for the pile 2 to sink is several tens of times longer than the time required for striking the pile 2 to stop driving.

Therefore, in the former case, a relatively small sound insulating cylinder is sufficient for sound insulation, but in the latter case, as described above, a very large sound insulating cylinder is required. In addition, 4 in FIG. 1 is a working machine.

The present invention solves the drawbacks of the prior art, and provides an IF device for a pile hammer that is easy to handle and transport and can significantly improve workability. A sound insulation device for a pile hammer, characterized in that a bellows-shaped enclosure made of an elastic material is provided, a liquid is filled between the pile and the bellows-shaped enclosure, and gas is mixed in the liquid. can get.

Next, the present invention will be explained with reference to the drawings.

FIG. 2 is a longitudinal sectional view of one embodiment of the present invention, and FIG. 3 is a simplified S-section of FIG. 2.

Sumirezu will now describe the principle of the present invention.

Liquids are generally said to have a self-attenuating effect. Therefore, the liquid can be used as a kind of sound absorbing material, and its handling is very easy. On the other hand, when the shock wave moves back and forth in the liquid, the water hammer phenomenon (water hammer phenomenon) occurs, which can generate unexpected destructive force.To prevent this, air is blown into the nuclear liquid to generate bubbles. The sound insulating cylinder must be shortened (as the pile sinks), the sound insulating cylinder must be shortened, and the sound insulating cylinder must be shortened as the pile sinks. The tube has a bellows shape that is relatively easy to expand and contract.Therefore, the bellows-shaped sound insulating tube can be contracted very much like an accordion or a lantern.

The above is a detailed explanation of the present invention, and next, the structure thereof will be explained.

As shown in Fig. 2, the pile driver 1 may be a hydraulic type or a diesel engine type.

If the hollow pile 2 is a pile without a foundation, no inner attachment is required. 6 is a water hole; 7. /fi A bellows-shaped aquarium,
It is foldable for easy transportation. 5-1 is a water pump, 5-11 is a check valve, 5-3 is an ML valve, 5-4 is an accumulator, and 6 is a water hole.

7 is a bellows-shaped water tank, filled with 8 tanks of water, 9, 9a
is a bellows-shaped J sound part, 10 is an air compressor, and if the rubber balloon 17 is to be buried, it is unnecessary to use it.

11 is a bubble or '4! Ki, 12 is weight, 13 is float.

14 is a stand (iron plate), 15 is the ground, and 16 is the weight of an air-filled rubber balloon.

Next, the effect will be explained.

Ahead f,! f tube 9e9air pile 2 or bailu nomaa 1
Fixed to. The resistor 2, sound insulation m9t9a, etc. are lifted together with the pile hammer 1, and as shown in FIG. 2, they are set at a predetermined position for piling, and then water is injected with the pump 5-1. Water is injected into the sound insulating cylinder 9a side from the water passage hole 6. When the water injection is finished, the counter 2 starts.

At the same time, the air compressor IO is operated and the air 11 is sound-insulated.
blows into the surrounding water. The filled water will leak a little, but it's not a problem. In addition, if the pressure is high (if
The return valve 5-3 is operated so that the filled water 8 returns to the water tank 7. The accumulator 5-4 is connected to each valve 5-2, 5-3 and the water pump 5- from the water hammer phenomenon.
This is to protect 1.

Next, we will discuss the effects.

When the pile hammer l hits the pile 2, the pile 2 deforms into a bellows shape or a beer barrel shape, and also deforms into a shape like an MJM thrush, which is the reverse of that shape, and repeats this deformation violently. . At the same time, elastic waves reciprocate inside the main body of resistor 2. Therefore, the amplitude and frequency of these vibrations causes the air to vibrate, which people perceive as sound, or noise. Therefore, this vibration is blocked by the water and the bellows-shaped shielding tube 9,
By absorbing and attenuating the sound at 9a and making the sound omnidirectional, the sound wave energy can be dispersed and consumed, so that the impact sound can be rapidly reduced. In other words, the sound waves that travel through water are approximately 1,500 m7s, while in iron they are 5,000"/s, so water's frequency is approximately 173 or lower than that of iron, so the phase difference is large (and for humans, it is that much more irritating. This means that it no longer feels like a certain sound.

Generally, the speed of sound traveling through a medium is expressed by the following equation.

The coefficient, ρ, depends on the density of the medium; in the case of rubber, E is small and ρ is large, so the speed at which sound travels is very slow, and when trying to deform in synchronization with the elastic waves, it requires a large amount of energy, - total elasticity. As it is absorbed from the waves, the elastic wave energy is rapidly depleted. Therefore, the contacting air can no longer be vibrated. People can't hear sounds. Note that the same applies to water. Therefore, the GFR cylinder made of water and rubber can have a much greater sound-dampening effect than conventional metal sound-insulating cylinders. As mentioned above, since the water and bellows-shaped sound insulating cylinders are easy to handle, it is obvious that the work efficiency is significantly improved. Furthermore, for the same reason, there is no resonance sound generated inside the pile, so the pile driving operation can be carried out very quietly.

Next, FIG. 3 shows the case of FIG. 2 7al--dark road.

The outside of the pile in Figure 3 is the same as in Figure 2, but the inside of the pile is different. That is, the inside of the pile is filled with water, and the weight 16 of an air-filled rubber boat is placed at the bottom. On the other hand, there is a case where several relatively large rubber balloons 17 are connected to each other by spring-like strings 18 and floated in the water. The rubber vessel 1z is used to attenuate water hammer, similar to bubbles in the water. Further, the pneumatic rubber balloon weight 16 installed at the bottom is used to prevent and attenuate elastic waves or pressure waves propagating in water from being reflected at the bottom surface. If the pneumatic rubber balloon catcher 16 has a bellows shape other than the shape shown in the figure, it will easily adhere to the inner diameter of the pile, thereby preventing water leakage. In addition, the pile is sinking
Needless to say, a lubricant should be applied to minimize the frictional force during the process.

Next, when the pile 2 is hit by the pile hammer l, it undergoes a complex deformation as described above. The liquid adapts to this deformation (including changes in volume) almost simultaneously Ic, so the displacement or change in the pile immediately changes into the driving energy of the water. Therefore, the fact that water or liquid has a free surface is suitable for dissipating kinetic energy.

Now, when the water or liquid is in contact with the rubber balloon 1, the apparent free surface has increased, and the volume of the rubber balloon 17 changes when the pressure wave passes through it, which is the area that consumes kinetic energy. The increased pressure on the button has the effect of eliminating or attenuating underwater pressure waves. Therefore, the silencing effect is also great in the case of FIG. Note that it is more effective to use highly viscous oil instead of water and blow air into it, since these bubbles are less likely to easily float to the surface and be released into the atmosphere.

The effects of the present invention are as follows.

(1) The bellows-shaped bellows part, which contains air and liquid and is made of extremely elastic material, is lightweight and expandable, making it easy to handle, that is, to transport, store, and assemble. The tear rate is high (Ryu's performance improves.

(2) A type of sound absorber that contains a mixture of liquid and gas adheres better to the pile than sound absorbing materials such as glass wool, so it directly absorbs the vibration energy of the pile, which is the source of noise peaks, and absorbs the gas and liquid. Since it can convert into kinetic energy, it has very good sound absorption efficiency. Furthermore, since the sound-insulating cylinder itself made of a hyper-elastic material can directly absorb the kinetic energy of the gas and liquid, it does not violently vibrate the air in contact with it, so there is less noise. \
Noise generated from the striking part between the hammer and the pile and the entire pile can be extremely reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of an example of a conventional example, FIG. 2 is a vertical cross-sectional view of an embodiment of the present invention, and FIG. 3 is a vertical cross-sectional view of another actual m-row of the present invention. In the figure, 1...Pile hammer + 5-4-...Accumulator 2#@-Pile (bailun 6...-1rfi Water hole 3...Sound insulation tube 7...Bells-shaped Water tank 4... Work equipment 8...Φ Water 11... Life, bubbles or air 12---- Weight 130... Float 14... Iron plate 150... Ground 16 @ fist air Filled rubber balloon weight 17...Tatami - Rubber balloon 185ees Spring-like string Patent applicant Ishikawajima Harima Heavy Industries Co., Ltd. Representative Yoshi Shirakawa Naome/Eye

Claims (1)

[Claims] +11 A pile nozzle characterized in that a bellows-shaped enclosure made of an elastic material is provided around the pile, a liquid is filled between the cough pile and the bellows-shaped enclosure, and gas is mixed in the liquid. Sound insulation device for cameras.