JPH04371603A - Compaction method of ground - Google Patents

Abstract

PURPOSE:To obtain the degree of compaction larger than compaction by one vibrating roll and make compacting a subbase course layer particularly in arbitrary depth under a road surface possible by concentrating vibrations from a plurality of vibrating rolls. CONSTITUTION:In vibrating rolls, in which two vibrating rolls R are connected before and behind, the direction S of vibration of the vibrating rolls R are inclined by an angle theta respectively. Vibrations from the grounding sections of each vibrating roll R to the lower section of a road surface are concentrated to a fixed section under the road surface at the central section of the front and rear vibrating rolls R, thus compacting a subbase course at a vibration concentrating section P.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of compacting ground using vibrating rollers.

0002

[Prior art] In the conventional ground compaction method, asphalt mix, cemented carbide concrete, etc. is spread on the ground using an asphalt finisher, and then a vibrating roll equipped with a vibrating roll that can vibrate up and down is used to spread the asphalt mixture or cemented carbide concrete on the ground using an asphalt finisher. The ground is compacted by rolling it with rollers and using the vibration of the vibrating roll and its own weight.

[0003] The vibrating mechanism of the vibrating roll that can vibrate vertically is, for example, two vibrating shafts arranged horizontally across the center of rotation of the rolling wheels and rotated in opposite directions while synchronized by gears. Moreover, by making the eccentric weights attached to both the vibration axes face in the same direction on the upper and lower sides, horizontal force is canceled out and only vertical vibration is generated.

0004

[Problems to be Solved by the Invention] In the conventional ground compaction method, compaction is carried out to a relatively deep part of the road surface by vertical vibration, but in order to increase the degree of compaction, the same vibrating roller Even if it is compacted two or three times, it does not compact beyond a certain level, and in order to compact it further, another vibrating roller with a larger vibration force must be used. At this time, even if a vibrating roller formed by connecting two vibrating rolls at the front and rear is used, conventionally the front and rear vibrating rolls are simply vibrated in the vertical direction separately to perform rolling.
There is no concept of concentrating the vibrations from both vibrating rolls, and it is not possible to apply vibrations below the road surface that are greater than the vibrations generated by each vibrating roll.

[0005] Another problem is that it is not possible to specify and compact a ground layer at an arbitrary depth. The present invention has been made with attention to the above-mentioned problems, and it is possible to specifically compact the ground at any depth under the road surface, and also to combine the vibrations from a plurality of vibrating rolls. The purpose of this method is to obtain a degree of compaction greater than that achieved by compaction using a single vibrating roll.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the ground compaction method of the present invention comprises a plurality of vibrating rolls whose vibration direction can be specified, connected at a predetermined interval in the front and rear. It is characterized by using vibrating rollers, and by intersecting the directions of vibration transmission from each of the ground contact parts of the plurality of vibrating rolls at a specific depth position in the ground, the vibrations from each vibrating roll are concentrated at that position. There is.

[0007]

[Operation] For example, by using a vibrating roller in which two vibrating rolls are connected at a predetermined interval in the front and rear, the vibration direction of the front vibrating roll is tilted backward from the vertical direction by an angle θ, and the vibration of the rear vibrating roll is When the direction is tilted forward from the vertical direction by an angle θ, the vibration generated from each of the front and rear vibrating rolls is transmitted from the ground contact part of each vibrating roll in a direction tilted by an angle θ, and the vibration is transmitted to the center between the front and rear vibrating rolls. Concentrates on the ground below the road surface and at a certain depth.

As mentioned above, if each vibration direction of a plurality of vibrating rolls connected in front and behind is specified and the direction of vibration transmission from the ground contact part of each vibrating roll intersects at a specific depth, the The vibrations from each vibrating roll concentrate in the deep part, particularly compacting the ground in that part. In particular, since the vibrations from each vibrating roll are concentrated and synthesized, the vibration energy to the vibration concentrated area becomes large, and the compaction to the vibration concentrated area is achieved with a greater degree of compaction than compaction with a single vibrating roll. It will be constructed.

By moving the vibrating roller while maintaining the vibration direction, the vibration concentration section moves horizontally while maintaining a constant depth, and the ground layers at a constant depth are successively compacted. . Note that the vibration roll used in the present invention, whose vibration direction can be specified, is, for example, disclosed in Japanese Patent Application Laid-Open No. 1986-
Those described in JP 315711 and the like are publicly known.

0010

[Example] This example will be explained based on the drawings. first,
To explain the configuration of the vibrating roll R used in this embodiment, as shown in FIG.
are provided spaced apart from each other, and a shaft hole 2a is formed in the center of each inner wall 2, coaxially with the center of rotation of the rolling wheel 1. A cylindrical vibration excitation frame 3 is disposed coaxially with the rolling wheel 1 between the two inner walls 2, 2, and cylindrical extension portions are provided at both ends of the vibration excitation frame 3, respectively. 3a, each is supported in the shaft hole 2a of the inner wall 2 via a bearing and is rotatable.

A vibration motor 4 is fixed to one extended portion 3a of the vibration generating body frame 3 (on the left side in FIG. 1), with a rotating shaft 4a inserted into the extended portion 3a. One end of a drive shaft 5 is connected to the end of the rotating shaft 4a of the vibration motor 4, and a gear train 6 is further connected to the other end of the drive shaft 5. The gear train 6 includes a drive gear 6a fixed to the drive shaft 5, a driven gear 6b meshed with the drive gear 6a, a first gear 6c fixed coaxially with the driven gear 6b, and a first gear 6c. The second gear 6d meshes with the gear 6c. And the first gear 6
Vibration shafts 7a and 7b are connected to the central axes of the second gear 6d and the second gear 6d, respectively.
The vibrating body frame 3 is arranged symmetrically and horizontally across the center of rotation, and is supported within the vibrator frame 3 via a bearing.

Eccentric weights 8 are eccentrically fixed to the pair of vibration generating shafts 7a and 7b with a phase difference of 180 degrees in the circumferential direction, and both eccentric weights 8 are fixed when facing in the vertical direction. They are provided so that they are in the same phase with each other. The extension portion 3a provided on the left side of the vibration generator frame 3 in FIG. There is.

[0013] Further, a protruding portion 3b is provided to protrude in the radial direction from the outer peripheral portion of the cylindrical extending portion 3a. The protruding part 3
The tip of a piston rod 12a of a cylinder 12 is swingably connected to the outer end of b, and the main body of the cylinder 12 is connected to the support 9, so that when the piston rod 12a of the cylinder 12 expands and contracts, the protruding end 3b can be rotated 90 degrees. Note that stoppers 13 and 14 are fixed to the support body 9, and come into contact with the protrusion 3b to restrict the rotation of the protrusion 3b from exceeding 90 degrees.

In the vibrating roll R having the above configuration, when the vibration motor 4 is driven, its power is transmitted to the drive gear 6a of the gear train 6 via the drive shaft 5, and the drive gear 6a
The driven gear 6b meshed with the driven gear 6b is rotated, and one of the vibration generating shafts 7a fixed to the driven gear 6b is rotated. Furthermore, synchronization is achieved by the first gear 6c and the second gear 6d, and the other vibration shaft 7b is also rotated at the same rotational speed in the opposite direction to the one vibration shaft 7a.

Due to the rotation, the pair of vibration shafts 7a, 7b
Each eccentric weight 8 attached to the
As shown in the schematic diagram b), they rotate in synchronization in mutually opposite directions. At this time, as shown in the schematic diagram of FIG.
In the centrifugal force generated by each eccentric weight 8, the horizontal component force constantly cancels each other out and becomes zero, and only the vertical component force is combined, so that only the vertical force acts and only vertical vibration is generated. .

When the piston rod 12a of the cylinder 12 is operated in the above state, the protrusion 3b connected to the piston rod 12a rotates in accordance with the movement of the piston rod 12a. Then, the vibrator frame 3 continuous to the protrusion 3b rotates around the rotation center of the rolling wheel 1,
Two vibration shafts 7a, 7 supported within the vibration body frame 3
b also rotates around the rotation center, thereby changing the vibration direction S of the vibrating roll R. That is, when the projection 3b is rotated by the angle θ due to the operation of the cylinder 12 device, the two vibration shafts 7a, 7b are rotated as shown in FIG.
The virtual plane H connecting these is also tilted by an angle θ from the horizontal direction, and the vibration direction S is also tilted by an angle θ from the vertical direction.
Therefore, the vibration is transmitted in a state where the vibration transmission direction F from the ground contact portion of the vibrating roll R to the road surface G is inclined by an angle θ.

As shown in FIG. 3, two vibrating rollers R having the above structure are connected at a predetermined interval (L in this embodiment) in the front and rear to compact the ground. Construction. The cylinders 12 in each of the front and rear vibrating rolls R are arranged in symmetrical positions, and the vibration direction S of the front vibrating roll R is set in the vertical direction by moving the piston rod 12a of each cylinder 12 back and forth. The vibration direction S of the vibrating roll R on the rear side can be tilted from the vertical direction to the front side.

Then, by moving the piston rod 12a of each cylinder 12 back and forth, the virtual plane H formed by each pair of vibration shafts 7a and 7b is tilted by an angle θ, and the vibration direction of both the front and rear vibrating rolls R is adjusted. S is selected from the vertical direction so that the front vibrating roll R side is tilted backward, or the rear vibrating roll R side is tilted forward by an angle θ. moreover,
When the vibration motor 4 of both the front and rear vibrating rolls R is driven, Fig. 7
As shown in , a direction F that is inclined by an angle θ (backward for the front vibrating roll R and forward for the rear vibrating roll R) with respect to the vertical direction from the contact point between the front and rear vibrating rolls R and the road surface G. The vibrations are transmitted to the
Under the road surface G at an intermediate position between the front and rear vibrating rolls R, and (
The vibrations are concentrated at a position P at a depth of L/2 )·cot θ, and the ground in that vibration-concentrated portion P is particularly compacted.

At this time, since the vibrations from both of the vibrating rolls R are combined in the vibration concentrating part P, vibration energy larger than the vibration energy of one vibrating roll R is applied to the vibration concentrating part P. , the degree of compaction of that portion P becomes even greater. When the vibrating roller is moved forward as it is, the concentrated portions P of each vibration caused by both the front and rear vibrating rolls R move while maintaining a constant depth, following the vibrating roller, and in this way, the ground layer at a constant depth is particularly Can be compacted.

The depth of the vibration concentrated portion P can be changed by changing the inclination angle θ of the vibration direction S by both the front and rear vibrating rolls R. In the above description, the inclination angles of the vibration direction S of both the front and rear vibrating rolls R are the same angle θ, but the vibrating direction S of the front and rear vibrating rolls R may be tilted at different angles. For example, as shown in FIG. 8(a), if the inclination angle of the vibration direction S of the front vibrating roll R is α, and the vibration direction S of the rear vibrating roll R is tilted by β, both the front and rear vibrating rolls R The vibrations caused by this are concentrated at a depth of L/(tan α+tan β) and particularly compact the ground at that depth.

Further, in the above embodiment, the vibration direction S of each vibrating roll R can be selected within a range of 90 degrees, but the selection of the vibration direction S is expanded to a range of 180 degrees, as shown in FIG. As shown in FIG. 8(b), the vibration concentrated portion P may be placed on the ground below the road surface G in front of the front vibrating roll R. Further, in this embodiment, only two vibrating rolls R are arranged at the front and rear, but a vibrating roller in which three or more vibrating rolls R at the front and rear are connected at a predetermined interval may be used. Even in this case, by tilting the vibration direction of each vibrating roll R at an appropriate inclination angle, each vibration can be concentrated at a specific depth position under a specific road surface G, as shown in FIG. 8(c). The soil at that depth can be particularly compacted.

Furthermore, since the vibration mechanism of the vibrating roll R of this embodiment is an example, if the vibration direction S can be specified and a plurality of vibration directions S can be selected, the vibrating roll R having another vibration mechanism can be used. Connected vibrating rollers may also be used.

[0023]

[Effects of the Invention] As explained above, in the ground compaction method of the present invention, it is possible to specify and compact the ground at any depth under the road surface. By concentrating the vibrating rolls, it is possible to obtain a greater degree of compaction than the individual compaction by each vibrating roll.

[Brief explanation of drawings]

FIG. 1 is a top sectional view showing a vibrating roll according to the present embodiment.

FIG. 2 is a cross-sectional view showing the rotation of the protruding portion of the vibrator frame by the cylinder.

FIG. 3 is a side view showing a vibrating roller.

FIG. 4 is a side view showing a rotating state of an eccentric weight fixed to an excitation shaft.

FIG. 5 is a schematic diagram showing the states of horizontal force and vertical force of centrifugal force of a pair of eccentric weights according to changes in phase.

FIG. 6 is a side view showing the vibration direction when a virtual plane formed by a pair of vibration axes is tilted.

FIG. 7 is a side view showing a concentrated state of vibration caused by front and rear vibrating rolls.

FIG. 8 is a side view showing a vibration concentration section according to another embodiment.

[Explanation of symbols]

7a, 7b Excitation axis 8 Eccentric weight 12 Cylinder R Vibration roll S Vibration direction F Vibration transmission direction P Vibration concentration part

Claims (1)

[Claims] [Claim 1] A vibrating roll whose vibration direction can be specified,
By using a plurality of vibrating rollers that are connected at a predetermined distance in the front and rear, and by intersecting the directions of vibration transmission from each ground contact part by the plurality of vibrating rolls at a specific depth position in the ground, it is possible to A ground compaction method characterized by concentrating vibrations from each vibrating roll.