JPS58500290A - Ground consolidation method and consolidation device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Material layer densification method and densification device This invention (a method for compacting or increasing the density of a material layer) , concerning a densification machine implementing this method. This methodological device, in particular, at least The purpose is to set what the mo-dora l＼ acts on the oyster quality due to gravity and vibrational force. ing.

In normal vibrating rollers or densification equipment, the vibrations e.g. This is achieved by means of a rotating eccentric device provided in the drum, where the drum is substantially circular or Given an elliptical path. Traditionally, get improved performance and reduce bearing stress In order to achieve this, devices exist that are equipped with several cooperating eccentrics.

Regarding this technology, there is a patent disclosed in Swiss Patent No. 384゜019. In this case, two eccentrics rotating in opposite directions are arranged. In that case, the forces generated by rotation balance each other in the horizontal direction, but in the vertical direction They are designed to complement each other in the orthogonal direction. This purpose is for drums and has the desired effect of having a substantially vertical densification force from the substantially vertical movement of the It's about letting go.

What is disclosed in French Patent No. 1,166.681 is that the drum The present invention relates to a vibrating roller including at least two vibrating bodies attached to a cylindrical surface.

Each vibrating body is driven in the same direction by a power transmission from the drum's central drive shaft. It contains a rotating eccentric mass. For slips or slides in power transmission equipment This results in harmonic frequencies in the vibratory motion of the drum.

For the degree of densification achieved in a material layer, the shear in the material layer being densified It is known from experiments that the number of alternations of stress directions is an important point.

Conventional vibratory rollers typically generate large and variable vertical downward forces.

This normal force itself increases the shear stress within the material layer, the magnitude of which is It varies with the operating frequency (vibration frequency) (hereinafter referred to as "eccentric frequency").

However, no appreciable tensile stress occurs at the interface between the roller and the ground surface. Since, the direction of shear stress does not change with eccentricity frequency. shear stress The change in direction of the roller is caused by the passage of the roller as it moves slowly over the layer of material. This is caused by a one-time static load.

[Simple periodic shearing device for dry particulate materials], [Geotechnical e-Test Ting Journal J; ASTM.

Voll, No. 2.1978, Ansel and Brown (Ansel Brown) describes a simple experimental setup for testing, where static negative As the load is applied, a rapid change of direction of shear stress is achieved within the material. .

Experiments using this device have shown that better densification effects can be obtained than with conventional techniques. Ta.

What is disclosed in U.S. Patent No. 5,5t5,656 is that It has two drums, each supported by a yoke connected to a frame. Regarding vibrating rollers. An eccentric mass rotates about a horizontal axis above each drum. are arranged on each yoke so that the This configuration results in a yoke and a With an eccentric drum, the rotating eccentric mass is located between the axis of the drum and the center of the eccentric mass. This causes the lower part of the drum to have a reciprocating component along the material layer. Gives exercise including.

The purpose of this invention is to apply shear stress while densifying the material layer so that the roller When passing over a material, stress repeatedly and rapidly changes direction within the material layer. A second object of the invention is to provide a densification machine comprising a drum. The installation provides a machine with relatively low stress on the part and the rest of the machine. Is Rukoto.

A third object of the invention is that the movement within the layer of material to be densified is It is to provide a densification machine that is substantially confined to a relatively small volume of layers. .

A fourth object of the present invention is to achieve a desired density within the material layer by using a relatively small The goal is to construct a densification machine that consumes only energy.

This invention densifies or densifies the material layer by using a drum that rotates on the material layer. It is based on the idea that the drum mainly has a substantially constant A downward gravity load of magnitude and a rapidly varying magnitude in the tangential direction of the drum. It is designed to apply similar alternating forces.

In this invention, these alternating forces that vary rapidly in magnitude are applied to the drum. by applying rapidly alternating substantially pure torque around the shaft of the will be achieved. Due to the reaction force from the material layer to the drum, and the drum is normally The absolute total of the drum when it is moved or propelled slowly along a layer of material, such as The motion is more complex than pure alternating rotational motion about the drum axis. This invention and What is important for densification and densification is that virtually pure alternating torque and the alternating frequency and magnitude of the torque are applied around the axis of If the torque is sufficiently high in relation to the rotation speed, the torque is independent of the rotation of the drum. produces rapid alternating forces in the plane of the material that are substantially parallel to the plane be.

Novel and particularly distinctive features of the invention and its advantages and implementation of the densification method; and a densification machine according to the method of this invention will be explained in detail with reference to the drawings. Make it.

Figure 1 shows the principle of densification theory according to the prior art (an paper by Ansell and Brown). figure.

FIG. 2 shows the opposite substantially vertical densification force and drum with two eccentrics rotating in the direction A principle diagram that provides the desired effect with the movement of.

Figure 6 shows the prior art disclosed in French Patent No. 1.166.681. Principle diagram of a densification device with two eccentric devices in the densification drum according to 0 FIG. 4 shows the prior art disclosed in U.S. Pat. No. 3,543,656. , a diagram showing the principle of a simplified microdensification device.

Figures 5A to 5D show that after this invention the drum has been substantially Basic principle diagram of applying pure alternating torque to .

FIG. 6 shows a vehicle propelled by rear wheels and equipped with the densification drum of the present invention in the front. Schematic side elevation of a self-propelled densification machine.

Figure 7 applies substantially pure alternating torque to the drum around its meticulous FIG. 8 is a partially cutaway perspective view of the method and apparatus for carrying out the A side view of the chemical machine.

FIG. 9 is a cross-sectional view of a part of an embodiment of the densification device of the present invention.

FIGS. 10A-B illustrate this output, which can be optionally set to normal or densification of the present invention. Schematic diagram of Ming's densification machine.

11 and 12 are schematic diagrams of another embodiment of the invention.

Figures 13 to 18 show the results of microdensification tests for embodiments of the densification machine of the present invention. Graphs of measurement results and quantities.

In connection with the laboratory experiments mentioned above, Ansell and Brown densification according to Fig. proposed the principle of They are designed to provide mutual shear stress. How does horizontal movement actually work? Information regarding whether it will be implemented or not will be omitted.

The desired drum movement is achieved in densifying the layer of material by conventional methods or by the present invention. There are many ways to create movement. Since the densification machine according to the above-mentioned paper and patent specification Later, in explaining the basic principles and ideas and the detailed explanation of this invention, a brief explanation will be given. Therefore, the motion of the drum in Figures 2-5 is caused by a rotating eccentric mass. Assume that

As shown in Figure 2, for example, As shown, the vertical forces and drum motion are caused by two eccentric masses 2a, 2b , and these eccentric masses are applied to shirts 3a and 3b of drum 1, respectively. Rotates as it is mounted. The shafts 3a, 3b rotate around the drum meticulously. It is mounted so that it follows only the lateral movement of the drum, not the rotational movement.

The eccentric masses are the same and the shafts are equidistant from the drum axis. Each shaft 3a , 3b, the eccentric masses 2a and 2b have the same speed, but in opposite directions. Rotates in sync with. Therefore, 2a and 3a are opposed to rotating clockwise. 2b and 3b counterclockwise in synchronization with 2a and 3a and at the same rotational speed. Rotate in the direction.

Due to this rotation, the mass and the drum each experience a force through the shaft. this The force interaction is a vector from the center of each mass pointing outward from the center of each shaft. Illustrated by Tor. The direction of the force changes synchronously with the angular position of the rotating mass. Ru. mutual orientation during synchronous rotation of masses 2a and 2b at the same rotational speed, i.e. Their mutual phase positions mean that the forces on the drum act together vertically, but not horizontally. They are selected so that they have opposite effects on each other. Mass mounted eccentrically when rotating does not impart any vibrational torque to the drum about the drum axis.

Figure 3 shows the densification device disclosed in French Patent No. 1.166.681. This shows the principle of generating motion for the ram. The rotation of the drum is produced by a pair or more vibrating bodies mounted inside the cylindrical surface of the ram. It will be done. The two vibrating bodies in pairs are located on either side of the drive shaft in the center of the drum. Each side of the ram center is adapted to be moved relative to each other in a fine direction. Each swing The moving body contains a mass that is eccentrically attached to the shaft and rotates with it. It has become so. The shaft is a power transmission device from the drive shaft in the center of the drum. It will be rotated depending on the position.

It is not clear whether the masses of a pair of vibrating bodies mounted eccentrically are the same. do not have. Also, power and motion transmission from the drive shaft to the eccentric shaft is ,shaft.

It is also clear whether the rotation speed is the same or almost the same. It's not.

On the other hand, in the specification it is stated that slipping or slipping in the transmission causes a phase difference between the eccentrics. It is stated that migration occurs. Due to this phase shift, the frequency of the vibrating body is Different vibration frequencies will be applied to the drum.

Figure 6 shows the mass attached to the shirt h3a rotating clockwise.

The force vector from the center of mass is directed away from the shaft 3a. S A second mass that is suspended on the shaft 3a and rotates synchronously with the mass 2a is connected to the hole 2b. Illustrated by The force vector that rotates synchronously with the mass 2b is caused by multiple arrows. is illustrated.

Although not clearly stated in the French patent specification, both vibrating bodies forming a pair are Due to slip and phase shift, and eccentricity along the fine direction of the drive shaft Differences in equipment location create complex combinations of moving forces and torques on the drum. I am using it. The torque is passed around the drive shaft and through the center of the drum. and act around the precisely orthogonal axis of the eccentric device. Therefore, France In those disclosed in the national patent specifications, substantially pure alternating torque is It is not applied to the details of the program.

U.S. Pat. No. 5,543,656 discloses a soil densification system with two drums. A machine is disclosed in which each drum has its own eccentric device located above it. It is designed to be vibrated by Each drum and eccentric device are attached to the frame. It is rotatably attached to an elastically suspended yoke.

Each eccentric causes vibrations not only of the drum, but also of itself and the yoke.

As shown in Figure 4, the motion, which is a combination of lateral and rotational motion, 3 and the center axis of the drum. Densification machine suspended freely in the air If the eccentric is When the machine densifies the material layer, the eccentric device brings the drum to point As it moves, the forces from the layers provide an alternating rotational movement. However, Therefore, in the above-mentioned US patent specification, an eccentric device is used to align the axis of the drum with respect to the drum. No substantially pure alternating torque is applied around.

The generation form of the densification movement of the drum of the densification machine of this invention is different from that of the prior art. The principle is different from what was explained.

Since a substantially pure alternating torque is applied to the drum about its axis, Driving without lateral forces directly generated by eccentric devices affecting the shaft of the drum. A vibratory force is applied to the material in contact with the periphery of the ram. The advantages of such a configuration are It has the advantage, in particular, that the drum movement is isolated from the densification machine frame. In this case, there are problems that are difficult to solve with regular vibrating rollers. are doing. 5A to 5D show a mode in which alternating torque is generated in this invention. are clearly shown, and these drawings show two eccentrics rotating synchronously in the same direction. The principle of the invention using masses 2a, 2b and masses in four different angular positions quantity is indicated. As is clear from the drawings, in Figures 5A and 5a, While the torque M for the fineness of the drum l due to the eccentricity 1t2a12b is zero, Fig. 5B shows its maximum value in one direction, and Fig. 5D shows its maximum value in one direction. In this case, the maximum value in the other direction is shown.

Furthermore, the eccentric mass does not exert any lateral movement force on the drum at any position. It is also clear that there is no such thing.

As is clear, the shafts 3a, 3b can be driven vertically, horizontally or along any diagonal line. Torque has no significance when it lies in the plane passing through the center of the system. essential The point is that the force vectors are synchronized and at the same time, as shown in Figures 5A to 5D. It means rotating at the speed and direction of rotation.

A densification machine 20 is shown in FIG. is provided. The densification machine 20 usually consists of two sections 21.22FC The front section 21 serves as a frame for holding the drum l. and is articulated with a rear section 22 for steering. Ru. The rear section 22 contains the drive seat 24 and possibly the driver's compartment. to propel the atomization machine through the rubber tires 23 and drive the eccentric device. A moving crab unit 25 that supplies power to the fluid motor 19 is held. drum 1 can be equipped with a driving fluid pressure motor (not shown) as usual. .

The densification machine shown in FIG. 6 is merely an example of the application of this invention; This is not a detailed explanation of the structure of the conversion machine.

FIG. 7 shows the structure of the device of the invention as shown in principle in FIGS. 5A-D. . A conventional drum 1 is provided which houses two pairs of eccentric masses 2m, 2b, said masses 2 a and 2b are arranged to rotate in the same direction and at the same speed.

Pair of eccentric masses 2-. 2b is the end wall F3a of the drum l.

8b attached to the shafts 3a and 3b, the solid axis of the drum is They are rigidly mounted at equidistant positions, so that the axis of the shaft 3 is at the front. It is in the same plane as the axis. The drive shirt for shaft centers 3a and 3b) 10 is inside the drum. It is mounted in the center. A motor 9 is provided on the outside of the wall at one end of the shaft 10. ing. The motor 9 also includes bearings, a housing, and It is elastically suspended on the frame 21 by an elastic device (not shown). driving shaft A suitable power transmission device from the shaft to the shafts 3a, 3b is arranged, which In FIG. 7, chain 2 or toothed belt transmission devices 4a, 5a, 6a and 4b , 5b and 6b. Also, gears can be used. other On the other hand, the transmission member can slip and no belt or similar is utilized; It is essential that the phase relationship between the eccentric masses of the pair remains unchanged at 180°. This is because it is a point. In actual implementations, a fine offset from this phase shift Sha does not significantly affect the intended function.

Eccentric mass 2-. shown near one end wall 8a of the drum. Apart from 2b, shaft 3 a, 3b hold a similar eccentric mass near the other end wall 8b of the drum. well known Several eccentric masses can be placed on each shaft, or The foot retains a uniformly distributed eccentric mass along all or most of its possible length can do.

The shape of the eccentric masses 2a, 2b shown in FIG. 7 merely constitutes an illustrative example of the invention. It's just that. Includes movement of the center of gravity from the shirt l and withstands the stress during application Other shapes of eccentric masses can be utilized within the scope of this invention. Of course that clause As a matter of fact, the eccentric mass has a substantially pure vibrational force relative to the drum about its axis. It is formed to bring about a certain amount of energy.

In the device described above, the eccentric mass has a sinusoidal shape relative to the drum about its axis. resulting in a fluctuating resultant torque, which causes the layer of material affected by the drum to Produces vibrational shear stress fluctuations. On the basis on which the drum should be densified or consolidated Upon contact, the forces at the contact surface between the drum and the foundation are in addition to the vibratory horizontal forces, constitutes the normal force resulting from the weight of the machine.

Slowly alternating shear stresses are possible, which cause the densification machine to move back and forth on the foundation. Depending on the speed at which the densification machine is passed over the foundation by the repeatedly moving plow.

Due to the weight of the densification machine, the densification of the material carried out in this way requires energy. The frequency (number of times) at which the densification machine is reversed is determined by the densification machine of the present invention. compared to the frequency at which the eccentric mass causes shear stress fluctuations on the drum. low 0 The invention can also be configured to include more than two eccentric devices within the drum. . These eccentrics are made common except for the angular position of their masses, and If the shaft is placed parallel to the axis of rotation of the drum, its axis will be parallel to the axis of the drum. The phase is uniformly separated along a circle coaxial with . Eccentric devices rotate synchronously in the same direction and The phase difference of the eccentric masses on the shaft is determined by the plane passing through each shaft axis and drum axis. equal to the angle between, therefore, all the forces from the eccentric mass correspond to Figure 5A. When this happens, it points radially outward from the axis of the drum.

The invention has many applications, for example where several drums are provided and the or even more so by a machine or a towing vehicle equipped with the eccentric device of this invention. Applies to machines that are propelled by Figure 8 shows such a trailer viewed from the - side. It shows the condition. This approximately 900K9 trailer-type densification machine has a hollow section. It is assembled on a frame or pedestal 61 formed from a A bar holder 40 is provided. While the drum 1 is suspended from the frame, the pressure A fluid tank 57 and pump 58 are held. Lower side of the front end of the holding body 40 A tensile quadrant transducer (conversion device) 45 is arranged at. Said Tran Sudeisa 451-1 - connected to the tow bar 44, the free end of the tow bar 44 A conventional towing connection 41 with a release handle 42 is provided by a bolt connection 43. is attached to connect the densification machine to the tow ball of the vehicle.

The holder 40 is formed from two rectangular hollow sections, these cefcicons are They are welded together at the ends that hold the lance deducer 45 and emanate from each other at an acute angle to the rear. They are scattered. The rear end of the holder is connected to the frame 61 by a bolt connector. It has a welded flange. The trestle 61 has a front frame section 46 and a portion A similar rear frame section 48 is included. These frame sections consists of hollow square frames that are welded together to form a square frame. , flanges 55 are provided at mutually opposing corners, and the bolt connectors 56 extend the length. It is adapted to be connected to a manual weldment. The front frame section 46 is At a distance from each front corner, a flap is welded to be connected to the retainer 40. It differs from the rear section in that it has a hinge. two frame sets Sections 46 and 48 are connected by two welds running in the longitudinal direction of the machine. each former is formed from an upper hollow section 47 and a lower hollow section 49. each end is provided with a welding flange, and a vertical hollow section fixing body 5 is provided. They are interconnected by 0°51. A hollow section 49 is provided between the fixed bodies. A shallow part is provided in the lower beam formed by pushing down the upper end line. ing.

A base structure 59 for mounting the pump 58 is provided on the upper side of the pedestal 61. The pump 58 is fed from the tank 57 and compressed by a motor (not shown). radial piston type for the fluid, thus forming a normal type fluid unit. It is. As is clear from FIG. 9, which is a partial cross-sectional view taken along line B-B in FIG. , the drum of the densification device is mounted on a pedestal 61 by means of a suspension plate (60.70). There is. The suspension plate 60 is attached to the three rubber shock absorbers using bolt connections. This is a front shock absorber 72, which is attached to the side of the solid axis of the drum 1. Rear impact device 71° and upper part mounted vertically above the solid axis of drum 1 A rubber shock absorber (not shown). The six shock absorbers are normal; It has a cylindrical shape, and both end faces can be screwed together to form an elastic connection between them. can. The end surface of the shock absorbing device facing away from the suspension plate 70 is connected to the pedestal. 61, and the front shock absorber 72 is fixed. screwed into the fixed plate 76 and welded together with the spacers 81, 82 of the fixture 50. The rear impact absorbing device 71 is installed by screwing into the plate 75. Together with the spacers 79 and 80 of the fixture 51, they form a weld. Correspondence not shown The upper shock absorber is attached to the upper beam 47 in such a manner. shock absorber Holes 52.5 are provided in both fixtures 50.51 and in the upper beam 47 to facilitate installation. 3 and 54 (see FIG. 8) are formed.

The suspension plate 70 on the other side of the drum 1 is attached to the front shock absorber on the plate 77. installation 73, mounting the rear shock absorber 74 on plate 78, and the associated upper Similarly, elastic suspension can be achieved through an upper shock absorber (not shown) attached to the has been done. The drum diameter is 60crn and its width is 85α. The container containing the contents The weight of the ram is 310Kf.

The contents of the drum 1 correspond in principle to that described in accordance with FIG. Therefore to drive the central drive shirt) 10, and the suspension play to drive the eccentric device) to 70. It is directly driven by the drive motor 9, which is fixed in place. The drive motor 9 is a fluid type. and is connected to pump 58 by a hose (not shown) in a conventional manner. driving shaft The foot 10 has each end wall 8a.

1. Attach the bearing housing 88.90 in the normal way to the bearing housing 88. It is. Housing 88.90a Bearing housing 87.89 Rotatable The housings 87.89 and 70.60 respectively are attached to the suspension brakes. The drive shaft 10 can be rotated independently of the rotation of the drum 1. I try to be able to do it. The rotation of drive shirt) 10 is caused by toothed bells h5a, 5b and Eccentric mass is maintained by four similar toothed wheels 5a, 4a and 5b, 4r+ It is synchronously transmitted to shafts 3a and 3b. Shirts h3a and 3b are each at the drum end Bearing housings 83, 86 and 84° screwed to section walls 8a, 8b By 85 the drum end wall 8a on the side of the drive shaft 10.

It is attached to 8b. Housings 83, 84, 85°86 are standard types. , roller bearings and bearing housings 87, 88, 8 Also used on 9.90. To make it symmetrical, shirts) 31L and 3bK are The same toothed wheels 91 and 92 as the toothed transmission wheels 4a and 4b are provided. ．． 92 is for each shaft the same distance from the center of the drum as each toothed transmission wheel. are installed symmetrically. Shirt) 3aK is provided with an eccentric mass 2a, and this This is screwed to the shirt h3a close to the bearing housing 83. Furthermore, a similar eccentric mass 2c is aligned with mass 2a and is connected to the other bearing halves. Close to housing 84, it is screwed to the shaft.

Similarly, the other shaft 3bVc has two similar eccentric masses 2b.

2d is provided, and the driving form of 31L and 3b is that both eccentrics on one shaft The central mass is displaced by 1000 with respect to the eccentric mass of the other shaft at the same rotational speed. In other words, the phase is shifted by 1800.

The densification machine may have two or more modes of operation, such as the vibration mode of the present invention; It is advantageous to have a normal vibration regime with a force substantially perpendicular to the foundation. be. In this state, the above-mentioned eccentric mass arrangement is changed to a phase angle of 1 on each shaft. This is achieved by varying the angle between 80° and O0.

An example of such a modification is that the eccentric mass of at least one shaft is It includes being able to rotate between two end positions with respect to the foot. each direction The end position at is such that the relative phase angle is 1800 when the shaft rotates in one direction. is selected so that when rotating in the opposite direction, the relative phase angle is 0°. same Although similar results can be achieved with more than two shafts and associated eccentric masses, , for operation according to the inventive concept, the phase angle between the different eccentric masses is The composition in the radial direction of the drum depends on the mutual geometrical relationship of the two shafts. The movement force must always be zero.

The lateral displacement force, i.e. the phase angle between all eccentric masses, must be non-zero in normal operation. must therefore work together to maintain its position relative to the centrally located shaft. Eccentricity ■ brings about an eccentric moment equal to the sum of the eccentric moments.

10a-b shows a drive shaft 10 and shafts 3a, 3b with eccentric masses. is shown, in which case the drive of the shaft is similar to that in Figure 7. It will be held in Fig. 10a is a partial view from the side, while Fig. 10b is a partial view from the side. It is a sectional view taken along the line AA in the figure. The main eccentric masses 30a and 30b in this case The part occupies 90° of the circular ring around each shirt h3a or 3b . The eccentric mass 30a is rotatable around the shirt h3a and the rest of the shaft 3& It is attached by a small annular portion 31a surrounding the portion. On the side of the annular portion 31a, A stop 32,33 is provided which is rigidly attached to the shirt h3a. Each stop body is It constitutes 900 parts of the ring around the circumference of the shaft, and its position is When the direction of rotation of is reversed, the eccentric mass 30a rotates 180° around its shaft. It is possible to move the angle. The other eccentric mass 30b is connected to the shaft 3b by a ring. The annular portion 31b substantially corresponds to the portion 31a. However, it is rigidly attached to the shaft 3b. The deviation shown in Figure 10 At the positions of the core masses 30a and 30b, the shaft is driven counterclockwise. , thus providing an oscillatory rotational motion relative to the drum. Both shafts 3a, 3b When the direction is reversed so that the shirt h3a is driven clockwise, the shirt h3a becomes an eccentric mass 30 & 1800 revolutions, but the eccentric mass 30b is fixed on the shaft 3b. and hence the eccentric mass 30a.

30b rotate in phase with respect to each other to provide normal vibratory operation of the drum.

Substantially pure vibrational torque in this invention is applied to the drum of the densification machine of this invention. In order to apply , there is no need to place 1 inside the drum. Of course, Dora There is a separate method and device for generating pure alternating torque about the axis of the motor. also exists. Figure 11.12 shows the driving force of the machine running back and forth on the material layer. A densification machine is shown in which the densification is obtained by driving a densification system. This machine's recommendation Acceleration is done by applying a torque to the drum around its axis. . This torque for moving the machine by rotating the drum is change its direction when the running direction of the machine is reversed. After machine on material layer The direction and reversal of forward movement may vary depending on vehicle speed and machine weight during densification operation. It cannot be done particularly rapidly, so the torque needed to propel the machine is changes its direction very slowly compared to the alternating frequency of the torque. Ru.

Figure 11 shows how to superimpose rapid reciprocating torque onto constant or slowly fluctuating torque. A conventional differential gear is schematically shown. The differential gear is equipped with a housing 100. Well, inside it, an input shaft 101 and an output shaft 102 each have a bearing. The journal is supported by groups 103 and 104.

A first gear 105 is attached to the input shaft and a similar gear 106 is attached to the output shaft. installed on. Two other gears 107a, 107b are gears 105, 106 are identical to and interlock with them within the housing. gear 107a, 107b (mahousing bearing 109a.

Journal parts 108a and 108b are provided for attachment to 109b. . The input shaft is rotated in a predetermined direction, for example clockwise, and If rotation is prevented, the output shaft will rotate in the opposite direction, in this case counterclockwise. be transferred. On the other hand, the housing is rotated in the same or opposite direction as the input shaft. and the output shaft, respectively, than if the housing were held stationary. , rotated quickly or slowly.

FIG. 12 facilitates the method of driving the drum 113 and at the same time is shown in FIG. to utilize differential gearing and provide essentially pure vibrational torque to the drum. A block diagram is shown. Move the entire densification machine backwards and forwards on the material layer The input shaft of the differential gear 112 is driven through the reduction gear 111 to A traveling motor 110 is provided. The output shaft of the differential gear is connected to the drum The device is then rotated in the usual manner around its axis.

A rotary motion transfer device 115 is connected to the housing 7 of the differential gear and is connected to the housing. In contrast, it provides reciprocating torque around the input and output shafts.

A motion transfer device that can convert normally continuous input rotational motion into reciprocating rotational motion or torque is driven by a vibration motor 114. The rotational speed of the vibration drive motor 114 is High compared to the rotational speed of the differential gear input shaft.

The apparatus according to the block diagram shown in FIG. 12 allows relatively slow rotational movement. The torque consisting of relatively rapid motion due to the alternating torque superimposed on this is the driver. Provided for ram's gross exercise. This device allows the drum to rotate over a layer of material. 6-9, the center of the drum and its Each of the circumferences results in approximately the same motion.

If desired or preferred, motor 110 may be used instead of motor 114. The rotary motion transfer device 115 may also be driven. The device shown in Figure 12 , elastic devices are suitably included between the different parts of the densification machine, but these The attachment of the parts to the equipment and machines is omitted for the sake of brevity.

Densification experiments were carried out using the embodiment of the densification machine according to Figures 8-9. densification The same embodiment was used, but with an eccentric mass, a shaft and its drive configuration. has been changed so that in FIG. It has only been rotated. Therefore, the relative phase position of the eccentric mass is It is done so that movement can be obtained. In this invention, the axis of the drum is around, eccentric masses of different dimensions to obtain vibration torque of different amplitude and frequency Experiments were conducted at different frequencies from 2.5 to 70 Hz.

A compact experiment was carried out on a foundation approximately 2 m long with natural gravel with a grain size of 0-32 ILI. was carried out and was well densified by a diaphragm densifier in a layer of 40 crn. . On top of this, 80crn of crushed base gravel with a particle size of 0-filter 2U was placed to ensure good densification. I was secretly exposed. The top layer of 25m spans an area 1.5m wide and 5m long. I was left free. Its upper surface is purified and then this surface is densified It was densified by passing it through the machine 16 times. The said machine operates for the entire time. The vehicle was then towed back and forth along the same route. The travel speed was constant, approximately 0.8"/sec.

Two different series of experiments are compared below, one with vibration according to this invention. One concerns the drum in its normal vibrating configuration.

In the latter case, the experimental series consists of a conventional Typical parameters are selected for the vibration densification machine, i.e. approximately 0.4 For the nominal amplitude of , the frequency is 50 Hz and the collected eccentric moment is 012~m. be.

Preliminary experiments on examples configured in vibrational mode show comparable densification results. is shown to be expected at large eccentric moments and low frequencies. Shake In dynamic mode, the nominal tangential amplitude on the cylindrical surface of the drum is approximately 0.8 tu. Therefore, an experimental series with a resultant eccentric moment of 0.24 K9m was selected. In the experimental series, the vibration frequency was 40 Hertz.

The densification results achieved in the experiment can be evaluated using the usual methods, e.g. leveling, plate bearing. Ring tests, isotope measurements and tracks embedded within the material layer to be densified. The transducer is evaluated by a transducer which takes into account the effects of movement within the material layer. I am starting to receive it. Additionally, the power consumption of the fluid motor is measured and The horizontal and vertical acceleration of the ramshaft and other quantities were sensed. to this invention Some interesting results and conclusions regarding are described below by Figure 15-18. Ru.

The level of the densified surface can be determined by measuring the level of three cross sections at 1 m intervals. was carried out. Straight steel bead with cross section of 50x50m and length of 05m At the center of each cross section, perpendicular to the running direction of the densification machine, a placed on the surface. A spherical surface is provided at the center of the steel beam above it, and the attack A scale leveling device is placed. Level readings are taken every second pass, initially This is done after passing twice. Permanent to the level after two passes, on the ordinate The amount of subsidence is given by U. In the figure, five measurement cross-sections and a flat surface in width are shown. Average values are shown. The lower curve shows the results for the rocking motion mode of this invention. And the upper curve shows the results for the normal vibration mode of operation. these The curve includes the combined densification effect of the 0.25 m thick top layer in the free state. the effect of the total amount of settlement, the potential for densification of the underlying layer, and the potential for lateral movement of material. The results will be shown. As is clear from this result, the rocking motion mode causes a very large The total amount of settlement can be obtained.

Apart from the total amount of subsidence at the surface, the deformation of the strata can be measured using a device called a deformation meter. determined. The deformometer consists of two horizontal cylinders, the circular ends of which are vertical thin elastic connected by rods. The rod is connected to the length measuring device built into the lower cylindrical body. be done. Changes in the distance between the cylinders are electrically detected with an accuracy of 0.01.

The center distance between the cylinders in this experiment was 75 mm. The deformation meter is the center of was placed in the free state surface layer in the stretched state at a depth of approximately 0.2 m. Both experiments The results from said deformometer placed similarly as in the series are shown in Figure 14. It is. The abscissa shows the number of passes in a logarithmic scale, and the ordinate shows the measured length, i.e. 75. The % deformation based on is given. This instrument is zeroed after one pass. It was. Therefore, the results are in terms of the % average deformation of a layer 75 fins thick; Its center is located at a depth of 0.2 m below the surface of the earth. From the results, we found that the simulation using the oscillating motion mode In Leeds, some high deformation is shown, but in natural soil materials. Considering the spread in this type of measurement, the difference is not significant.

After the final densification work of each experimental series, a rigid disk with a diameter of 300M was used to A seat load test was conducted. Plate load test conducted in 6 cycles Loading and unloading were carried out for 10KN, 20KN and 50KNK. Bullet The gender module was calculated by the following formula for the first and second loads, respectively. El or x2=0.75Dg Here, 92 disk diameter Average stress increase value on the disk surface during loading of Δσ two problems Plate loading test in the subsidence children's picture experiment series for the stress increase value of the ΔS two problems. The results from the test are shown in FIG. The calculated module is the maximum of the abscissa. For large loads, it is shown on the ordinate. Modulus at the first load (El) and the modulus at the second load (E2) are shown. obtained elasticity The modulus all decreases somewhat after densification by the rocking drum of the present invention. Ru.

The measurements were performed using an isotope instrument manufactured by DECCA as model HDM-5. It is also carried out by indirect measurement of densified soil layer density. for two measurement positions As an average value, the isotope instrument, after densification with a rocking drum, Kf/, with a volume density of 1 and 2240 after densification with a normal vibrating drum. A volume density of K9/3 was given.

Different measurement methods do not give clear results regarding the densification results obtained. Not possible. The level measurement results show that the oscillating motion mode has a fairly high densification effect. However, depending on the plate load test, some information about the oscillatory operating mode A high densification effect was shown, and depending on the other two measurement methods, the rocking motion mode Somewhat high effectiveness has been shown for ψ.

Other mechanical and environmental conditions were provided for both experimental series mentioned above. For example, the power required to drive an eccentric device, the drum suspension plate It includes vibrations of the ground and pedestal, and vibrations at the ground surface at a distance from the densification machine. It will be done.

The power required to drive an eccentric mass is measured in the motor driving the eccentric mass. calculated from the measured pressure drop and the measured rotational speed rpm. thus The power recorded and supplied to the drive motor of the eccentric mass is It is used for compaction work, but it is also used for fluid motors, shaft bearings, and belt transmissions. consumed in the form of internal losses in the delivery device. No eccentric mass is installed, In particular measurements, the loss effect is approximately 800W at 1-t40 Hz.

It was measured to be about 1.000 W at 50 Hz.

The graph in Figure 16 shows the power supply to the eccentric mass drive motor during the two experimental series mentioned above. It shows the power that is generated. The number of passes through the densification machine is shown on the abscissa and the total power is The coordinates are shown. The upper graph is normal vibration densification, the lower graph is oscillation. It is about densification. Power consumption is fairly constant for each series , in the case of rocking, it was about 60% of that in the case of normal vibration. The results of densification are mutual Considering that the power losses in each case are considered to be comparable, As can be seen from Figure 16, the efficiency is greater in the case of oscillation over a wider range. This shows that it is quite high.

The results obtained from the recorded vertical and horizontal accelerations on the suspension plate 60 The result is shown in FIG.

− The polar line for the acceleration vector tip movement during the period is the normal vibration operating mode. and drawn for rocking motion mode. Unwanted frame as shown The vertical amplitude, which is the most important for movement, is different in rocking mode than in normal mode. This is about 20% of the corresponding amount. The horizontal amplitude in rocking mode is the same as that in normal mode. It was about 30% of the corresponding value.

In the case of rocking drums, by increasing the mass without elastic cushions, For example, by rigidly connecting a certain part of the pedestal to the suspension plate, further horizontal It is possible and appropriate to reduce the velocity amplitude. This further , the advantage is that the amplitude of the tangential motion at the drum periphery along the contact surface with the material layer is increased. , so that the friction between the drum and the material layer is sufficient to prevent slipping. If the size is large, the densification effect will be increased. The corresponding measurement is a normal vibration densification machine In this case, the substantially radial oscillation of the drum is greatly damped, and if this damping is compensated for by an increase in the eccentric moment. This results in high vibration amplitudes for the rest of the pedestal.

In Fig. 18, another variation of the vibration amplitude at the ground surface far away from the densification machine is shown. The results from the study have been shown.

This study was carried out in a static microdensification machine on a large, flat horizontal asphalt surface. It was done. From below, this foundation is made up of clay, gravel layer of unknown thickness, and asphalt. It is composed of The measurement location is on the asphalt surface, and it becomes denser when driving forward. 0°, 450.900.1350 and 180 relative to the center line of the machine path Marked at a distance of 1,2°4 and 8m from the center of the drum along the line at It will be done. A two-axis accelerometer with radial and vertical measurement directions is placed at the measurement point. It will be destroyed. The rotational speed rpm value of acceleration in each direction is the eccentric mass rotating. recorded in between. The horizontal axis of Figure 18 shows distance on a logarithmic scale, and the vertical axis shows one distance. Logarithmic scale converted to m/62 maximum value, assuming a sinusoidal oscillation with frequency components shows the acceleration amplitude. This result shows the size of the composite ing. The five radial directions are indicated by separate lines. The above-mentioned series of comparative experiments The same eccentric mass was utilized as in In case of oscillating motion mode, the comparison series The frequency was 40 hertz, as was the case. When in vibration operating mode, the machine Because high vibrations cause lateral movement, high frequencies such as the 50 hertz mentioned above It wasn't available. Therefore, in this case, the result for the frequency of 40 herns is is given. The upper group of curves in Figure 18 is for a normal vibrating drum; The lower group of curves is then applied to the rocking drum. As is clear from the diagram, vibration The level is 8 to 10 times lower in the case of rocking, and the directional characteristics are also different. a place of oscillation In this case, the amplitude transverse to the drum (90° curve) is either forward (0°) or backward ( 1800,). At distances less than approximately 3 meters from the machine, The opposite is true for vibrations.

After testing the embodiment of the densification machine, its drum surface has a very smooth surface. child This indicates that the surface is slipping against the material layer during densification. , indicating that the entire motion cannot be transferred to the material layer. Therefore, on the basis On the other hand, a drum with high friction, for example a drum with a rubber coating, provides good precision. It is thought that the result of increased density can be obtained.

In summary, the experimental results show that the purpose of this invention is to develop a densification machine as shown in Figures 8-9. It is shown that this can be achieved by This example and Figures 6-7 and 11 The embodiment shown in Figures 1 to 12 is considered to be an example of the state in which the object of this invention is realized. However, the present invention is not limited to these embodiments.

Figure 1 Figure 2 Figure 5 Figure 6 Figure 7 10th (1c Figure 10b Figure 11 Figure 12 Pa Figure 18 rn/s2 international investigation report

Claims (1)

[Claims] 1. moving a densification machine having at least one drum over a layer of material; A method for densifying the material layer, wherein the drum is subjected to gravity and rocking force. In a method that acts more on the layer of material, the material layer is The rocking force is generated by applying a substantially pure alternating torque around the center. high frequency compared to the frequency at which the running direction of said densification machine is reversed. A densification method characterized in that the direction of action of the torque is reversed. 2. The drum is provided with at least two synchronously rotating eccentric devices spaced apart from its axis. and applying said torque to act on said drum by said eccentric device. such that the forces applied are substantially neutral to each other in any radial direction of the drum. The method according to claim 1, characterized in that the eccentric device is arranged in a manner that . 6. At least one drum, said drum being subject to gravity and rocking relative to the layer of material. By moving a densification machine that applies a force over the material layer, the material is In an apparatus for densifying a layer, substantially a torque generator that imparts said rocking force by applying pure alternating torque to and at a high frequency compared to the frequency at which the densification machine reverses its running direction. The present invention is characterized by comprising a torque generating device configured to reverse the acting direction of the torque. A densification device with a characteristic. 4. The torque generating device includes at least two eccentric devices that rotate synchronously, and An eccentric device is spaced apart from the drum axis and its synchronous movement causes the eccentric device to The forces exerted on the drum by the core device are proportional in any radial direction of the drum. are substantially in equilibrium with each other and provide substantially pure torque about the axis of said drum. As set forth in claim 3, the invention is characterized in that they work together so as to form a equipment. 5 said eccentric devices are substantially similar and each device rotates parallel to the center of said drum; A common synchronous rotation is performed around the rotation axis, and the rotation axis of the eccentric device is arranged at uniform intervals on a circle concentric with the drum, and rotated by the rotation of the eccentric device. All forces acting on the drum are directed radially outward from the axis of the drum. 5. A device according to claim 4, characterized in that: 6. The force exerted by the rotation of the eccentric device is constantly and instantaneously The invention is characterized in that it can be set so that the The device according to claim 4 or 5. 7 The setting of the eccentric device is performed by reversing the rotation direction, and The position of at least one eccentric mass of the eccentric device is determined by the rotation described by the eccentric device. so that one of the 12 terminal positions can be taken depending on the fixed part. 7. The device according to claim 6, characterized in that: 82 eccentrics are provided, the eccentric mass of one eccentric being on its retaining shaft. partially rotatable in the eccentric, and when the direction of rotation of the eccentric device is reversed, half of the mass Claim 1, characterized in that the radial angular position is shifted by substantially half a rotation ( 3? ). 9 Rotating the drum to provide a driving force for moving the densification machine over the material layer and the torque generating device is configured to apply torque to an output shaft (lO2 ) connected to the drum, the travel motor (110) The input shaft (101) of the differential gear is driven by the swing motor (114). A rotary motion transfer device (115) driven by the differential gear 7 00) to apply reciprocating torque to the housing. Apparatus according to claim 6.