JP2002285537A - Dynamic consolidation method and dynamic consolidation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic consolidation method and a dynamic consolidation device capable of satisfying ensuring of strong dumping force/avoidance of trouble/labor reduction/shortening of a construction period/solution of the difficulty of work/reduction of a construction cost/simplification of the device/ extension of the life of the device, or the like. SOLUTION: Earth and sand are conveyed to the inside of a storage section 36 of a dumping chute 31 rising by setting on the ground G through a conveying machine 71, and an earth and sand mass S is formed of the earth and sand. The earth and sand mass S is dumped along the inside of the chute from the inside of the storage section 36 of the dumping chute 31 to collide with the ground G, and the earth and sand mass S is cut into the ground G by impacting energy produced when the earth and sand mass S collides with the ground G and, at the same time, the ground G is compacted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic compaction method and a compacting apparatus for compacting a ground in civil engineering, construction, waste disposal and other technical fields.

[0002]

2. Description of the Related Art In the dynamic compaction method widely used in the field of civil engineering and construction, a hammer lifted high above the ground is freely dropped toward the ground, and the ground is compacted by utilizing the collision energy at that time. It is a technology. This is known as tamping because it squeezes the ground.

[0003] The dynamic compaction method is roughly classified into a hammer connection type and a hammer detachable type. In the case of a hammer connection type, after the hammer (steel or concrete) connected to the tip of the wire rope is wound up with a winch, the winch is released without separating the hammer from the wire rope, and the wire rope is unwound and the hammer is unwound. To the ground. In the case of a hammer detachable type, the hammer is held by a detacher connected to the tip of a wire rope, and is wound up by a winch, then separated from the detacher and dropped to the ground. In each method, the lifting step for lifting the hammer and the dropping step for dropping the hammer are repeated as many times as necessary.

As described above, it is common technical knowledge in this field to use a hammer for the dynamic compaction method. Regarding the improvement of soft ground by the dynamic consolidation method, tamping is carried out by this tamping work and finish tamping, etc. In connection with this, backfilling and leveling are also performed.

[0005]

The dynamic compaction method using a hammer has the following problems. Repeated lifting and dropping of the hammer is too time-consuming. Troubles often occur during hammer handling. Especially with the hammer connection type, the entanglement of the wire rope often occurs. High skill is required for hammer operation to avoid trouble. The hammer that has penetrated the ground due to the fall must be pulled out by the work called “ground cutting”.
The pulling load at that time is about 3 to 4 times as large as the hammer.
This means that a large cooler that can be ground-cut is required for hammer operation. It is conceivable to increase the number of moving pulleys as a means of alleviating the increase in the size of the coolen, that is, to increase the hoisting force by reducing the speed of the wire rope to secure the pulling load. However, deceleration has the effect of taking longer to wind up. Although the hoisting time can be reduced by the full rotation of the engine, such measures result in severe handling of the coolen, and thus the mechanical elements of the coolen and the wire ropes are worn out early.
In the dynamic consolidation method, when tamping also serves as part of the backfilling work and the leveling work, labor, construction time, construction cost, etc. can be dramatically improved. However, tamping with a hammer has no relevance to both of these operations, and so no such improvement can be made.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above technical problems. In other words, the present invention is based on the technical idea of using sedimentary agglomeration, to secure a strong tamping force, eliminate work difficulty, avoid trouble, reduce labor, shorten construction period, reduce construction costs, simplify equipment, and reduce equipment service life. Extension,
It is an object of the present invention to provide a dynamic compaction method and a dynamic compaction device which can satisfy these requirements.

[0007]

The dynamic consolidation method according to the first aspect of the present invention is characterized by the following means for achieving the intended purpose. That is, the dynamic consolidation method according to claim 1 uses a drop chute having a storage portion on an upper side as being movably installed on the ground, and conveys as a means for feeding earth and sand into the storage portion of the drop chute. Using a machine, and carrying sediment via a transfer machine into a storage section of a drop chute that is set up on the ground and rises, and forms a sediment nodule with the loaded sediment, and stores the sediment nodule in a drop chute. It is characterized by dropping from the inside of the chute along the inside of the chute and colliding with the ground, causing the sediment lumps to bite into the ground with collision energy when the lumps collide with the ground, and consolidating the ground.

In the dynamic compaction method according to claim 2 of the present invention, in the method according to claim 1, the installation location of the drop chute is changed in order to compact various parts of the ground, and the sediment nodules are placed on the ground at various parts of the ground. It is characterized by collision.

The dynamic compaction method according to claim 3 of the present invention is characterized in that, in the method according to claim 1 or 2, the air in the chute is evacuated from the lower side surface of the chute when the sediment agglomerate falls. .

The dynamic compaction device according to the third aspect of the present invention is characterized by the following means for achieving the intended object. In other words, the dynamic compaction device according to claim 3 is provided with a drop chute for movably installing on the ground and a transport machine for feeding earth and sand to the upper side of the drop chute, and the upper part of the drop chute. On the side, there is provided a storage section for storing sediment to form sediment agglomerate and dropping the sediment agglomerate, and the upper side of a drop chute with a storage section for sediment and the The carry-out sections correspond to each other.

According to a fourth aspect of the present invention, there is provided the dynamic compaction method according to the third aspect, wherein an exhaust portion for exhausting air from the chute is provided on a lower side surface of the drop chute. I do.

[0012]

In the case of the dynamic compaction method according to the present invention, a drop chute having a storage section on the upper side is first set on the ground, and earth and sand are conveyed into the storage section of the drop chute by a transfer machine. Each sediment in the reservoir becomes a sediment agglomerate (one lump of sediment). Next, the earth and sand nodules are dropped from the storage portion along the inside of the falling chute at a stretch. In this way, the sediment nodules fall at a high speed and collide with the ground while maintaining a lump state without scattering. As a specific example, by dropping 50 m ³ of soil Nodules (weight about 80t) from the reservoir portion of the height of 20m and to collide with the ground. The collision energy of the earth and sand nodule at that time is (80 t) × (20 m) = 1600 t · m. The value obtained by multiplying this value by the attenuation rate (attributable to the voids of the earth and sand) is the substantial collision energy of the earth and sand nodules, and the ground improvement depth of 20 m or more can be secured. In the conventional method as a comparative example, when a hammer of 25 t is dropped from a height of 25 m, the collision energy is 625 t · m, and the ground improvement depth is 15 m. As can be understood from this comparison, the method of the present invention enables a high degree of dynamic compaction with a tamping force higher than that of the conventional method. In the method of the present invention, the installation location of the drop chute is changed, and the earth and sand nodule collides with the ground at each location, whereby the large ground can be compacted without difficulty.
Further, when the earth and sand nodules fall, the air in the falling chute is exhausted to reduce the air resistance, so that the decay rate of the collision energy can be kept low.

The dynamic compaction device according to the present invention has the above-described configuration for dynamic compaction. Therefore, when the dynamic compaction device according to the present invention is used, the method of the present invention can be rationally implemented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a dynamic compaction method and a dynamic compaction apparatus according to the present invention will be described with reference to the accompanying drawings.

1 to 4 showing an embodiment of a dynamic compaction device according to the present invention, a self-propelled vehicle 11 shown in FIG. Things. The traveling unit 12 mainly includes an infinite rail (crawler) and / or wheels that are driven by receiving the power of the engine, and the body unit 13 includes a crane operating mechanism.
It has a vehicle steering mechanism and others. Body part 1
On the front side of 3, a boom 15 which has a flat bifurcated (eg, U-shaped) mounting portion 14 at the upper portion and is attached to the front portion of the revolving frame with a pin is provided so as to be able to be turned upside down. And hydraulic or pneumatic telescopic arm 1
6 is swingably equipped. The body portion 13 further includes a sheave holding body 19
20 and a winch (not shown) for winding and unwinding the wire rope 21 are also provided. The end (rewind end) of the wire rope 21 rewound from the winch has a boom 1 via sheaves 17 and 18.
5 attached to the mounting portion 14.

The drop chute 31 illustrated in FIGS.
Is a tubular structure made of a rigid metal such as steel. The cross section of each part of the drop chute 31 may be circular or polygonal, but a typical example is a square cross section. Further, regarding the drop chute 31, the lower chute 32, the upper cylinder 35, the hopper 61 and the like are main constituent members. Upper and lower cylinders 32
Speaking of the relative relationship between the upper and lower cylinders 35, the upper cylinder 35 is several times longer than the lower cylinder 32, and the diameter of the lower cylinder 32 is slightly larger than that of the upper cylinder 35. The lower cylinder 32 has a plurality of fin-shaped legs 33 on a lower outer peripheral surface, and has an exhaust portion 34 communicating with the inside and outside on an upper side surface. However, the opening (exhaust outlet) at the external terminal of the exhaust unit 34 faces downward. Upper cylinder 35
Has a reservoir 36 on its upper side. In the example of FIGS. 1 to 4, the storage section 36 is configured by the upper space of the upper cylinder 35 and a pair of opening and closing members 37 and 38.
An operation mechanism for this is attached to 38. As is particularly apparent in FIG. 3, a pair of opening windows 39 and 40 are provided on both upper side surfaces of the upper cylinder 35 for inserting and removing the distal end portions of the two opening / closing members 37 and 38. The two opening / closing members 37 and 38 are arranged at the two opening windows 39 and 40 and are rotatably attached thereto. For that purpose, both open / close members 37
38 has fulcrums 41 and 42 in the middle of these upper surfaces. Usually, a plurality of the fulcrum portions 41 and 42 are provided along the width direction of the opening / closing member. In addition, both opening / closing members 37 and 38 have connecting portions 43 and 44 for connecting these operating members, respectively, on the upper surface of the rear end. Normally, the connecting portions 43 and 44 are also provided near both upper corners on the rear end side of the opening / closing member. Upper cylinder 3
5 have fulcrum portions 41 of both opening and closing members 37 and 38 on both sides.
The supporting portions 45 and 46 corresponding to 42 have both open windows 39 and 40.
Near the upper edge. A pair of jacks 47 and 48 for operating the two opening and closing members 37 and 38 are of a hydraulic type or a pneumatic type.
52 are provided. Both jacks 47 and 48 are attached to the front and rear surfaces of the upper cylinder 35 with the extension shafts 49 and 50 facing upward. In this case, the two opening / closing members 37 and 38 are configured such that the fulcrum portions 41 and 42 and the coupling portions 43 and 44 are fulcrum shafts 53.5.
By being connected by 4, it is rotatably attached to both side surfaces of the upper cylinder 35. Further, a plurality of connecting arms 55 and 56 are applied to the connecting portions 43 and 44 and the connecting pieces 51 and 52, and both ends of the connecting arms 55 and 56 are connected to them by connecting shafts 57, 58, 59, and 60. Be linked. Therefore, a pair of opening / closing members 37.3 having fulcrums 41 and 42 are provided.
8, when the telescopic shafts 49 and 50 of the jacks 47 and 48 are operated to expand and contract, their open / close ends are both open windows 39.4.
It is opened and closed in such a manner that it goes in and out of the upper cylinder 35 from zero. On the other hand, the hopper 61 has a cylindrical shape that is inclined in a mortar shape as shown in FIGS. A monitoring camera 63 is attached to the hopper 61 via a stay 62. Regarding the combination structure of the lower cylinder 32, the upper cylinder 35, and the hopper 61, the upper cylinder 35
The hopper 61 is detachably connected to the upper cylinder 35 on the upper end side of the upper cylinder 35 while being inserted therein.

The thus assembled fall chute 31 is assembled to the self-propelled vehicle 11 as is apparent from FIG. That is, the drop chute 31 has a part of the upper cylinder 35 fitted into the attachment part 14 of the boom 15 and connected thereto, or the tip of the telescopic arm 16 is pivotally attached to one side (left side) of the lower cylinder 32. It is assembled to the self-propelled vehicle 11. The driver's seat of the self-propelled vehicle 11 is also provided with an operation system (not shown) for the jacks 47 and 48 and a monitor (not shown) connected to the monitoring camera 62.

The drop chute 31 is combined with a transport machine 71 as shown in FIGS. As the transporting machine 71, various types can be adopted as long as they can transport and throw earth and sand into the storage section 36 of the drop chute 31. A specific example of the transfer machine 71 is a self-propelled and revolving belt conveyor, that is, a stage spreader. The stage spreader includes a receiving conveyor and an unwinding conveyor, and these conveyors can independently raise and lower. This transfer machine 71
Also, a monitoring camera 73 is attached via a stay 72. A monitor (not shown) for the surveillance camera is also provided in the driver's seat of the self-propelled vehicle 11.

When the dynamic compaction method for compacting the ground G with the dynamic compaction apparatus illustrated in FIGS. 1 to 4 is carried out, the following is an example. First, the self-propelled vehicle 11 is run to set the drop chute 31 at a tamping point on the ground G, or the unloading end of the transfer machine 71 is arranged on the hopper 61 to link the drop chute 31 with the dropper 31. Or Next, a certain amount of earth and sand is thrown into the storage section 36 of the drop chute 31 while the earth and sand is transported by the transport machine 71. FIG. 4A shows this state. As apparent from FIG. 4 (A), each of the earth and sand put into the storage unit 36 becomes a cluster of earth and sand and becomes the earth and sand cluster S. After that, the earth and sand nodule S
Jacks 47.4 in order to drop the oil from the storage 36
8, the telescopic shafts 49 and 50 are immersed in the jacks 47 and 48, respectively. In connection with this, as a series of operations, connecting pieces 51 and 52 at the distal end (upper end) of each telescopic shaft.
Dropping, the two connecting pieces 51 and 52 pull the two connecting arms 55 and 56 in these lowering directions, and the two open / close members 3
The opening / closing ends of 7.38 rotate instantaneously in the direction of the arrow in FIG. Then, since both opening and closing members 37 and 38 are opened as shown in FIG. 4 (B), the earth and sand nodules S fall in the falling chute 31 at a high speed while maintaining a lump state without scattering. In the falling chute 31 at this time, the falling sediment nodules S exhaust air from the exhaust unit 34 to the outside of the chute while pushing down lower air. And the sediment nodules S falling at high speed
When it reaches the lower end of No. 1, it collides with a tamping point on the ground G as shown in FIG. The collision energy at this time is strong. Therefore, the sediment agglomeration S compacts the tamping point of the ground G and simultaneously penetrates itself into the ground. This means that the intrusion (recessed portion) of the ground G is filled with the sediment nodule S at the same time as the tamping.
Part of the backfill work and leveling work associated with dynamic consolidation also proceed simultaneously. As for the drop chute 31, the telescopic shafts 49 and 50 of the jacks 47 and 48 are respectively protruded upward after the fall of the sediment nodule S to return to the open / close members 37.3.
8 returns to the closed state of FIG. 4 (A), and can be prepared for the next tamping operation. When the same portion of the ground G is to be repeatedly tamped, the above operation may be performed as many times as necessary. When the other portion of the ground G is to be tamped, the drop chute 31 is moved to the tamping point and the above operation is performed. Just do it.

In a general example of compacting a vast ground or compacting a ground in a wide area for constructing an artificial island, the construction area is divided into construction sections of an appropriate size, and tamping is performed in the construction section order. Work to spread the floor. Figure 5
The compaction of the ground described with reference to FIG. 6 shows an example of tamping construction in such a case. This is an example of compacting the ground when creating an artificial island.

In FIGS. 5 and 6, since the drop chute 31 is mounted on the self-propelled vehicle 11, it can be moved to any point. 5 and 6, there are two types of transport machines. One transport machine 71 is the stage spreader (self-propelled and swiveling belt conveyor) described above, and the other transport machine 74 is a shiftable conveyor. The shiftable conveyor (transfer machine 74) is also a self-propelled and revolving belt conveyor. This is used for transporting earth and sand from a lifting vessel to a land (for example, an artificial island) when a lifting vessel such as a reclaimer vessel is used as a lifting facility on the sea surface. In the example of FIG. 5 and FIG.
Are connected back and forth, and another transfer machine 74 is connected to the transfer machine 71 on the rear side. In this case, the transporting end of the front transporting machine 71 corresponds to the upper part of the drop chute 31 so that earth and sand can be put into the storage section 36 of the chute.

The tamping of the ground G performed in FIGS. 5 and 6 is the same as that described in FIG. That is, the drop chute 31 is set at the tamping point of the ground G, and the storage section 36 of the drop chute 31 is
A certain amount of earth and sand is put into the inside, and the earth and sand nodule S is dropped from the storage part 36 at a stretch to collide with the tamping point. However, in the example of FIG. 5 and FIG. 6, since the various points of the ground G are multi-point tamped, the falling chute 31 is moved and the transporting machine 71 is shifted accordingly. A specific example at this time is as follows with reference to FIG. Introduction to tamping the tamping point _{P 11.} After tamping at this point, the falling chute 31 is moved to the arrow X in FIG.
It is moved in a direction by a predetermined distance, after shifting the conveying end of the conveyor machine 71 by following this, tamping tamping point P _12. The following tamping each tamping point _P 13 _{~P 18} in the same manner. When the tamping is completed so far, the falling chute 31 is moved to the arrow Y in FIG.
After moving the transfer end of the transfer machine 71 in accordance with the predetermined distance in the
Tamping ₂₁ Then, the falling chute 31 is moved to FIG.
It moved in the reverse X direction by a predetermined distance, after shifting the conveying end of the conveyor machine 71 by following this, tamping tamping point P _22. The following also tamping each tamping point _P 23 _{~P 28} in the same manner. Subsequently, the falling chute 31 is moved from the tamping point P ₂₈ to the same P.
_The tamping point P ₃₁ is then tamped after the transport end of the transport machine 71 is shifted to follow the shift of the transport end. After that, at each tamping point P in the same manner
₃₂ · P ₃₈ } is sequentially tamped. In this way, the compaction of a vast ground such as the creation of an artificial island and the compaction of the ground in a wide area of land will proceed rationally.

As a specific example of the present invention, a weight of about 80 t
As described above, when the sediment nodules S are dropped from the storage unit 36 having a height of 20 m and collide with the ground G, the collision energy of the sediment nodules S becomes 1600 t · m. The value obtained by multiplying this value by the attenuation rate becomes the substantial collision energy of the sediment agglomeration S, and the ground improvement depth of 20
It has already been mentioned that m or more can be secured. In the case of the present invention, it can be estimated that if the ability to supply earth and sand to the storage unit 36 is increased, tamping of the earth and sand lumps S of 100 to 200 t can be performed 100 to 200 times / day. The improvement depth of the ground G is also, for example, (weight of the sand mass S 100 t).
In the case of x (the height of the storage part 36 is 25 m), it can be said that the conventional example is surpassed. The drop chute 31 has a height of about 30 and a weight of 20 to 40 t. In addition, in the dynamic compaction method and the dynamic compaction device using the earth and sand nodules S, the hammer is not used, so that there is no need to cut the ground. Therefore, the crane mounted on the self-propelled vehicle 11 is one time smaller than the conventional 130-150t class.
It can be reduced to 00t class.

Since the type of earth and sand used in the present invention is not particularly limited, various types of earth and sand used in this kind of field can be employed. Among these, soil generated at construction sites, bad soil used for landfill, etc.
Further, those obtained by adding an improving material to soil generated on site or defective soil are also included. Of course, the earth and sand may be mixed with pebbles, crushed stones, etc., and moist ones can also be used. When the soil contains moisture, its moisture content is 30% or less, especially 20% or less (eg, 5 to 15%).
%) Is desirable. The earth and sand containing moisture and moisture tends to maintain a lump when the earth and sand aggregate S is formed, and the residual air is relatively small or hardly seen.

In the present invention, the storage portion 36 of the drop chute 31 has a bottom portion which can be opened and closed mainly by a pair of opening and closing members 37 and 38. This means that the bottom of the storage section 36 opens in both directions. As another example, a single opening / closing member may be used to make the bottom of the storage section 36 a one-sided opening / closing structure. As another example, the storage unit 36 may be made of an open-topped container, and may be provided inside the upper part of the drop chute 31 in a reversible manner. Transfer machine 7
1 may be a normal belt conveyor or a bucket type conveyor. In addition, any machine that can scoop soil and transport it into the storage section 36 of the drop chute 31 can be used as the transport machine 71.

[0026]

The dynamic compaction method and apparatus according to the present invention have the following effects.

Storage part (high place) for falling chute
And collides it with the ground, so that a strong tamping force can be secured by the collision energy. Therefore, the compaction effect of the ground by this tamping is high.

At the time of tamping, the work is not difficult because only the earth and sand is put into the storage part of the falling chute and the earth and sand nodules are dropped onto the ground. This effect is particularly large when compared with a conventional example in which a hammer is operated by a crane. Therefore, the dynamic compaction method can be performed without requiring a high level of skill.

Since the sediment nodules are merely dropped by gravity from the storage portion of the drop chute, almost no trouble occurs. Therefore, the construction proceeds smoothly compared to the conventional hammer / crane system in which the wire rope is apt to be entangled.

Consolidation of the ground at the same time that the earth and sand nodules bite into the ground is only a tamping operation.
In addition, part of the backfilling and leveling work can be performed in synchronization with this. Therefore, it is possible to reduce labor, shorten a construction period, and reduce construction costs.

Since the apparatus is mainly based on a falling chute having a storage section, the configuration of the apparatus is simple. The falling chute is
In addition, since it is only for putting earth and sand and dropping the earth and sand nodules, it is not subjected to severe handling, and therefore, the service life of the apparatus is prolonged.

[Brief description of the drawings]

FIG. 1 is a front view schematically showing an embodiment of the apparatus of the present invention.

FIG. 2 is a right side view of the apparatus of FIG.

FIG. 3 is an enlarged sectional view of a main part of the apparatus of FIG. 1;

FIG. 4 is a longitudinal sectional view schematically showing an embodiment of the method of the present invention in the order of steps.

FIG. 5 is a front view schematically showing another embodiment of the method of the present invention.

FIG. 6 is a plan view of the method of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Self-propelled vehicle 15 Boom 31 Drop chute 32 Lower cylinder 34 Exhaust part 35 Upper cylinder 36 Storage part 61 Hopper 71 Transport machine 74 Transport machine G Ground S Earth and sand mass

Claims (5)

[Claims] 1. Use of a drop chute having a storage portion on the upper side as a device movably installed on the ground, and use of a transport machine as a means for feeding earth and sand into the storage portion of the drop chute, and The sediment is carried into the storage part of the falling chute that is installed on the ground and rises through a transporting machine, and the sediment nodule is formed with the conveyed sediment. A dynamic compaction method characterized by dropping along the ground to collide with the ground, and using the collision energy generated when the sediment nodules collide with the ground, causing the sediment nodules to bite into the ground and compacting the ground. 2. The dynamic consolidation method according to claim 1, wherein the installation location of the drop chute is changed in order to compact various parts of the ground, and the earth and sand nodules collide with the ground at various parts of the ground. 3. The dynamic compaction method according to claim 1, wherein when the earth and sand nodules fall, air in the chute is exhausted from the lower side surface of the chute. 4. A falling chute for movably installing on the ground, and a conveying machine for feeding earth and sand to an upper side of the falling chute, and storing sediment on an upper side of the falling chute. And a storage part for dropping the sediment nodule, and the upper part of the drop chute with the storage part for the sediment correspond to the sediment discharge part of the transfer machine. A dynamic consolidation device characterized by the following: 5. The dynamic compaction device according to claim 4, wherein an exhaust portion for exhausting air in the chute is provided on a lower side surface of the drop chute.