JPS6329231A - Measuring instrument for tamping degree of tamping device for base ground - Google Patents

Abstract

PURPOSE:To efficiently measure the degree of tamping in a short time and to improve the measurement efficiency by detecting acceleration at the time of or almost at the time of the collision of a tamping member and deciding the degree of the tamping of a ground base based on the detected acceleration. CONSTITUTION:While a vehicle is moved forth at specific run speed, a roadbed is excavated to specific depth by a cutting conveyor 7 and screw cutters 10a and 10b and roadbed ground is conveyed to behind a 1st tamping device 9 by the conveyor 7. The exposed roadbed ground is hit by the vibrating plate 9a of the device 9 to tamp the roadbed ground to the specific degree. Further, the roadbed ground conveyed by the conveyor 7 is dropped on the roadbed hardened by the device 9 and laid almost uniformly by a screw spreader 12. The laid roadbed is hit by the vibrating plate 11a of a 2nd tamping device 11 to tamp the ground to the specific degree. The rotational frequency of exciters 9b and 11b are set above a specific value and when the acceleration detected by an acceleration sensor 13 reaches a specific value, it is decided that the ground is tamped as specified.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a compaction degree measuring device in a compaction device for compacting foundation ground such as road subgrade soil or roadbed.

<Prior Art> The degree of compaction of subgrade soil or roadbed for roads, etc. needs to be formed so as to satisfy a predetermined standard up to a predetermined depth. For this reason, in the past, for example, the subgrade soil was raised to a predetermined height, e.g.
0 to 30 cm) and compact it using a compacting device such as a road roller. Further, subgrade soil is spread to a predetermined height on the compacted subgrade and compacted by the compaction device. In this way, the degree of compaction of the subgrade soil is formed to a predetermined depth to satisfy a predetermined standard.

<Problems to be Solved by the Invention> Conventionally, in order to measure the degree of compaction of subgrade soil or roadbed, the density is measured from a compacted subgrade soil or roadbed specimen, and the density is The degree of compaction was measured by

However, in the method in which the degree of compaction is measured by taking a specimen after compaction and measuring the density, it takes time to measure the degree of compaction and the measurement efficiency is not good.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a compaction degree measuring device for a compaction device that can efficiently measure the compaction degree of foundation ground such as subgrade soil in a short time. shall be.

Means for Solving the Problems> For this reason, the present invention provides an acceleration sensor that detects the acceleration at or near the time of collision of a compaction member that repeatedly collides with the surface of the foundation ground, and a and a compaction degree determination device that determines the compaction degree of the foundation ground based on the basis of the compaction degree determination device.

<Operation> In this way, the degree of compaction of the foundation ground is measured from the acceleration of the compaction member, thereby compacting the foundation ground efficiently in a short time.

<Example> An example of the present invention will be described below based on FIGS. 1 to 5.

First, the tightening device will be explained based on FIGS. 1 and 2. A steering wheel 2 and a driving wheel 3 are attached to a lower front end and a lower rear end of a vehicle frame 1, respectively. A steering mechanism (not shown) is connected to the steering wheel 2, and a drive unit W (not shown) is connected to the drive wheel 3. A driver's seat 4 is provided at the rear of the vehicle frame 1, and a control device 5 for controlling the steering mechanism, the drive device, and various devices described below is provided in the vehicle frame 1 in front of the driver's seat 4. Further, a hydraulic pressure supply device 6 is provided at the front of the vehicle frame 1 to supply hydraulic pressure to various devices via the control device 5.

A cutting conveyor 7 is attached to a substantially central portion of the vehicle frame 1 and extends in the longitudinal direction of the vehicle, and a guide plate 8 is provided below the cutting conveyor 7 along the conveyor 7. And canting con hair 7
The subgrade ±8, which serves as foundation ground, is excavated to a predetermined depth and transported and supplied to the rear of a first compaction device 9, which will be described later, while being guided by the guide plate 8.

Also, on both sides of the cutting container 7, there are rotary screw cutters 1 for excavating the subgrade soil A to a predetermined depth.
0a and lOb are provided, respectively.

These screw cutters lOa and 10b have spiral blades formed in opposite directions from the center and collect the excavated subgrade soil to the cutting container 7 in the center. Then, these subgrade soils are transported and supplied to the rear of the first compaction device 8 by the cutting container 7.

A first compaction device 9 is provided below the cutting conveyor 7.
is provided. As shown in FIG. 3, the first tightening device 9 includes a diaphragm 9a as a tightening member extending in the direction of the inside of the vehicle, and a plurality of diaphragms arranged at predetermined intervals on the diaphragm 9a. The exciter 9a is composed of an eccentric cam type vibrator 9b that vibrates the vibrator 9a primarily in the vertical direction. The first compaction device 9 is configured to compact the subgrade soil excavated and exposed by the cutting conveyor 7 and screw cutters 1°a and 10b to a predetermined compaction degree.

Further, a second compaction device 11 is provided at the rear of the vehicle frame 1, and the second compaction device 11 compacts the subgrade soil B conveyed and supplied by the canting conveyor 7 to a predetermined degree of compaction. It has become. Similar to the first tightening device 9, the second tightening device 11 includes a diaphragm 11 extending in the direction of the vehicle J.
a, and a plurality of vibration exciters 11 arranged at predetermined intervals on the diaphragm 11a and vibrating the diaphragm 11a primarily in the vertical direction.
It is composed of b.

A screw spreader 12 is provided between the first tightening device 9 and the second tightening device 11 so as to extend toward the interior of the vehicle. This screw spreader 12 has spiral blades formed in opposite directions from the center,
The subgrade soil conveyed and supplied from the cutting conveyor 7 is conveyed toward both sides by the blades and is spread approximately evenly.

Further, as shown in FIG. 3, the diaphragm 9a of the first compaction device 9 is provided with an acceleration sensor 13 that detects the vertical acceleration of the diaphragm 9a, and the detection signal of this acceleration sensor 13 is It is input to the control device 5. Further, a rotation speed sensor 14 is provided to detect the rotation speed of the eccentric cam of the vibrator 9b of the first compaction device 9.
The detection signal is input to the control device 5. Also,
A speed sensor 15 is provided to detect the running speed of the vehicle,
The detection signal of this speed sensor 15 is input to the control device 5.

The control device 5 is provided with a first converter 16 for D/A converting the rotation speed detection signal, and the first converter 16 outputs a conversion signal to the rotation speed display meter 17 and the compaction degree determination section 18. do. Further, the control device 5 is provided with a second converter 19 for D/A converting the acceleration detection signal, and the second converter 19 is connected to the compaction degree determining section 18. Acceleration display meter 20 and integrator 21
Outputs the converted signal. The integrator 21 integrates the converted acceleration to determine the displacement of the diaphragm 9a in the vertical direction,
This displacement signal is output to the displacement display set 22. Further, the control device 5 is provided with a third converter 23 for D/A converting the traveling speed detection signal, and the third converter 23 outputs a conversion signal to the traveling speed indicator 24 and the traveling speed control section 25. do.

The degree of compaction determination section 18 determines the degree of compaction of the subgrade soil from the rotational speed of the vibrator 9b and the acceleration of the diaphragm 9a, as will be described later, and also determines the degree of compaction of the determined subgrade soil. A compaction degree signal corresponding to the above is output to the traveling speed control section 25. Further, the compaction degree determining unit 18 applies the rotation speed control signal for controlling the rotation speed of the vibrator 9b so that the determined compaction degree of the subgrade soil becomes a predetermined target compaction degree. Shaker 9
Output to b.

Further, the traveling speed control unit 25 controls the traveling speed so that the entire surface of the subgrade soil uniformly reaches a predetermined target degree of compaction based on the detected traveling speed and the determined degree of compaction of the subgrade soil. The set traveling speed control signal is output to the drive device that drives the drive shaft 3.

Further, the control device 5 is provided with a setting section 26 for setting a target compaction degree and running speed of the subgrade soil, and the setting section 26 sends setting signals to the compaction degree determining section 18 and the running speed control section 25, respectively. Output.

Note that 27 is a drive motor that drives the cutting conhair 7.

Next, the action will be explained.

While the vehicle is moving forward at a predetermined running speed, the subgrade soil A is excavated to a predetermined depth using the cutting conveyor 7 and the screw cutters lQa and 10b, and the excavated subgrade soil is transferred to the first compaction device 9 by the cutting conveyor 7. Transport to the rear.

Then, the vibrating plate 9a of the first compacting device 9 is struck against the excavated and exposed subgrade soil to compact the subgrade soil to a predetermined degree of compaction. Further, the subgrade soil transported by the cutting conveyor 7 is dropped onto the subgrade soil compacted by the first compaction device 9, and is spread approximately evenly by the screw spreader 12. The vibrating plate 11a of the second compaction device 11 is struck against the covered subgrade soil to compact the subgrade soil to a predetermined target compaction degree.

Incidentally, when the diaphragms 9a, 11a are driven into the subgrade soil, the acceleration when the diaphragms 9a, 11a are raised vertically due to the reaction of the subgrade soil depends on the degree of compaction of the subgrade soil. . Specifically, as the degree of compaction of the subgrade soil increases, the acceleration increases and converges to a certain value when the degree of compaction exceeds a predetermined degree. Further, the converged acceleration is generated by the vibrator 9b.

As shown in FIG. 5, when the rotation speed of the vibrator 9b, llb exceeds a predetermined value C, it becomes a substantially constant value.

Therefore, if the rotational speed of the vibrators 9b and llb is set above the predetermined value C, the subgrade soil will move when the acceleration detected by the acceleration sensor 3 reaches the predetermined value D shown in FIG. It can be determined that the compaction has been achieved to a predetermined target compaction degree.

In this way, the rotation speeds of the accelerators 9a and 11b can be controlled to compact the subgrade soil to a predetermined target compaction degree.

Then, while compacting the subgrade soil to a predetermined target compaction degree, the traveling speed of the compaction device is variably controlled, and the entire surface of the subgrade soil is compacted to approximately a predetermined target compaction degree.

As explained above, since the degree of compaction of the subgrade soil is determined by detecting the acceleration of the diaphragm 9a that compacts the subgrade soil, compaction hardness measurement can be carried out quickly and efficiently. The measurement efficiency can be greatly improved.

In addition, in this embodiment, the subgrade soil exposed by excavating the subgrade soil is compacted to a predetermined target compaction degree by the first compaction device 9, and the excavated subgrade soil is compacted. Since the subgrade soil is transported and supplied and compacted to a predetermined target compaction degree by the second compaction device 11, the subgrade soil can be compacted to a predetermined target compaction to a deeper place than before by just driving the vehicle once. It can be compacted to a high degree of compaction, greatly improving work efficiency compared to conventional methods, and thereby reducing construction costs.

In this embodiment, the diaphragm 9b detects the acceleration immediately after the collision with the subgrade soil, but the acceleration at the time of the collision with the subgrade soil may also be detected. Furthermore, although the rotational speed of the vibrator 9b and the running speed of the compaction device are automatically controlled, when the running speed is controlled manually by the driver, the running speed and the vibration excitation speed are controlled by the control device 5. It is sufficient to display the rotational speed and acceleration of the machines 9b and 11b and to move the vehicle forward when the roadbed reaches a predetermined target degree of compaction.

In addition, in the case of autopilot, if the traveling speed is set to a substantially constant value and the rotational speed of the vibrator 9a is controlled so that the acceleration becomes a predetermined value, a predetermined target degree of compaction can be secured. .

Furthermore, even if the traveling speed is changed based on the rotation speed and acceleration of the vibrator 9a, a predetermined target degree of compaction can be similarly ensured.

<Effects of the Invention> As explained above, the present invention measures the degree of compaction of the foundation ground by detecting the acceleration of the compaction member that compacts the foundation ground. Since it can be carried out quickly and efficiently, measurement efficiency can be greatly improved.

[Brief explanation of the drawing]

Fig. 1 is a side view of the compaction device, Fig. 2 is a plan view of the same, Fig. 3 is a perspective view of the main parts of the same, Fig. 4 is a block diagram of the control device of the above, and Fig. 5 is the operation of the same as the above. It is a characteristic diagram for explaining.

Claims (1)

[Claims] In a foundation ground compaction device that compacts the foundation ground by repeatedly colliding a compaction member against the surface of the foundation ground, an acceleration sensor detects acceleration at or near the time of collision of the compaction member, and the detected acceleration A compaction degree measuring device in a compaction device for foundation ground, comprising: a compaction degree determination device that determines the compaction degree of the foundation ground based on the above.