JPH0735652B2 - Ground improvement device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a ground improvement device for injecting a ground improvement material into soft ground, mixing and stirring the material to create an improved columnar body, and improving the soft ground. is there.

2. Description of the Related Art A method of injecting an improving material into soft ground, mixing and stirring the same to form an improved column is disclosed in, for example, Japanese Patent Publication No. 59-4504.
As shown in No. 9, various methods have been performed.As an apparatus for carrying out this construction method, although not shown, a drive unit is attached so as to be able to move up and down along the leader of the pile driver, and this drive unit Connect a pipe with a stirring blade equipped with an injection nozzle at the lower end, rewind the wire with a winch, and wind the wire to penetrate the pipe tip to a predetermined ground depth,
Then, a pipe is used in which the improving material is sprayed while gradually pulling out this pipe.

Problems to be Solved by the Invention By the way, in the above-mentioned construction method, it is required to form a uniform improved columnar body, but in the above-mentioned device, the pipe is drawn out by the winding operation of the wire by the winch. Therefore, it is difficult to make fine adjustments such as a winding operation at a constant speed or a stepwise withdrawal operation in the unit of several tens of millimeters. Therefore, it has been impossible to construct a reliable and uniform improved columnar body. This is because the diameter of the wire wound around the drum changes during winding and winding. In the past, it was generally wound at a speed of about 6 m / min, and it was difficult to achieve a speed of several tens of millimeters / min.

The present invention has been made to solve such a problem, and an object thereof is to make it possible to make a drawing speed of the pipe substantially constant and to easily perform a stepwise drawing operation in units of several tens of millimeters. It is possible to provide a ground improvement device which is capable of forming an improved columnar body which is substantially uniformly and sufficiently filled.

Means for Solving the Problems Referring to the drawings showing an embodiment of the present invention, in FIGS. 1 to 6, an elevating member 2 movably provided on a reader 1 provided in the up-down direction; An up-and-down moving device 4 for winding and lowering 2 with a wire 3; a fluid pressure cylinder 6 having a drive device 5 provided on the elevating member 2; a stirring head 7 provided at the tip end provided on the drive device 5. A ground improvement device comprising: a pipe 8; a nozzle provided in the stirring head 7; an improvement material supply device 10 provided in communication with the pipe 8; an actuation device 11 for the fluid pressure cylinder 6. is there.

Further, the ground improvement device is formed by adding the following various devices. That is, a depth detecting device 12 for detecting the depth of the nozzle 9 in the ground; a position detector 13 for detecting the position of the driving device 5 with respect to the elevating member 2, and the position detector.
13 and a setter 14 for setting a numerical value, and a logic circuit 16 connected to the automatic and manual switching switch 15 and connected to the actuating device 11; an arithmetic unit 17 and a comparator 18 provided in the logic circuit 16; A ground improvement device comprising a timer circuit 19.

Furthermore, the logic circuit 16 has the operating circuit 20 connected to the depth detecting device 12, and the ground improvement device is characterized in that.

Action The hydraulic cylinder 6 is extended, the drive device 5 is located at the lowermost position with respect to the elevating member 2, the drive device 5 is then activated, and the wire 8 is repeated by the vertical movement device 4 while rotating the pipe 8. put out.

As a result, the stirring head 7 at the tip of the pipe 8 is penetrated into the ground while stirring the ground.

In this case, the depth detecting device 12 indicates the depth of the stirring head 7. When the same depth reaches the measurement depth, the penetration into the ground is stopped, and the improved material is pressure-fed from the supply device 10 to the pipe 8 for automatic,
Manual switching switch 15 is automatically switched to fluid pressure cylinder 6
Activate contraction.

At this time, the improving material is sprayed horizontally from the stirring head 7.

Next, the contraction operation raises the driving device 5, and its position is notified to the logic circuit 16 by the signal from the position detector 13. Then, the signal is compared with a preset value in the setter 14, and when the preset value is reached, the output signal activates the timer circuit 19 in the logic circuit 16 and activates the actuating device 11 therewith, and The contraction operation of the pressure cylinder 6 is stopped.

In this stopped state, the timer circuit 19 operates and continues for a predetermined time, during which the improving material is injected into the ground. Next, after the stop of the fluid pressure cylinder 6 has passed for a predetermined time, the actuating device 11 is actuated again to perform the contracting action. Hereinafter, the same operation is repeated up to the stroke of the fluid pressure cylinder 6.

Next, the automatic / manual switching switch 15 is switched from automatic to manual, the operation of the fluid pressure cylinder 6 is stopped, and the pumping of the improved material is stopped at a glance. In this state, the vertical movement device 4 is operated and the lifting member 2 is moved. Is pulled up by the length of the stroke of the fluid pressure cylinder 6.

In this case, the actuating device 11 is actuated, the fluid pressure cylinder 6 is extended, and the drive device 5 and the pipe 8 are lowered with respect to the elevating member 2. Next, the pumping of the improved material is restarted, the automatic / manual switching switch 15 is switched from manual to automatic, and the same operation is repeated thereafter.

It should be noted that there is no problem even if the automatic / manual switching switch 15 is only manual, and the fluid pressure cylinder 6 is contracted or extended to pump or stop the improved material to arbitrarily form a pillar of the improved material. .

Example A pile driver was used in the apparatus of the present invention as shown in FIG. In the figure, 22 is a pile driver, 23 is a guide pipe, and 24 is a hanging sheave. The elevating member 2 moves up and down along the guide pipe 23. As the vertical movement device 4, a winch of a pile driver 22 was used. The drive unit 5 is composed of a motor and a speed reduction mechanism, and is slidably provided on the guide pipe 23 in the same manner as described above.

In FIG. 5, reference numeral 25 denotes a cylinder guide, and one end of the inner casing 25a is fixed in a state where the fluid pressure cylinder 6 is built in the lifting member 2, and the outer casing 25b is formed by fixing the inner casing 25a to the outer surface of the drive unit 5. It is formed by being inserted into the above to prevent the thrust load of the fluid pressure cylinder 6.

A hydraulic cylinder was used as the fluid pressure cylinder 6.

Next, the stirring head 7 is, for example, as shown in FIG.
A stirring blade 26 is provided in the lateral direction, and a nozzle 9 is provided at the lower end of the head 7 and the tip of the blade. And the nozzle 9
Each of them has a valve mechanism incorporated therein, which serves as a differential pressure valve in which one is opened and the other is closed by the hydraulic pressure supplied.

Further, the position detector 13 is a winder for the measuring wire 27,
An end portion of the length measuring wire 27 is connected to the elevating member 2, and the length measuring wire 27 is wound and unwound as the elevating member 2 moves up and down. Then, a pulse is generated depending on the length.

As a means for detecting the vertical movement distance of the drive unit 5 with respect to the lifting member 2, a bar 28 serving as a scale is suspended from the lifting member 2 as shown in FIG. 3, and the length of the bar 28 is detected. The position detector 13 is provided in the drive device 5. This position detector 13 is, for example, as shown in the same figure,
Small holes 29 are provided in the bar 28 at equal intervals (25 mm as an example), and photoelectric switches 30 are arranged on both sides of the bar 28 passing through the small holes 29.

In the figure, 30a is a light source part such as a light emitting diode, 30b is a light receiving part such as a phototransistor, and this photoelectric switch 30 has a small hole 29.
The movement of the driving device 5 and its distance are detected depending on whether or not light passes through.

In addition, although not shown, a resistance member, a magnet piece, or the like is embedded in the bar 28 to electrically detect a change in resistance or a change in magnetic field to detect the movement of the drive device 5 and its distance. May be. As described above, the signals detected by the depth detection device 12 and the position detection device 13 and output by this are input to the logic circuit 16. The logic circuit 16 is connected to a setter 14 for setting the rising distance of the drive unit 5 and an automatic / manual switching switch 15, and the control signal output from the logic circuit 16 operates the fluid pressure cylinder 6. The solenoids 32 and 33 of the solenoid valve 31 provided in the device 11 are controlled. Further, in FIG. 4, reference numeral 20 designates an operating circuit for generating signals to the display 34, the recorder 35 and the like. In the device of the above embodiment, the setting device 14 is 25 mm or 50 mm in advance.
It was carried out by setting the value of. The contraction stop time of the fluid pressure cylinder 6 was 6 seconds. There is no problem if the improving material is injected when the stirring head 7 penetrates. In this case, the pressure feeding pressure is adjusted so that the downward nozzle 9 is opened. The operation of the apparatus according to this embodiment is substantially the same as the operation of the invention described above, and therefore the description thereof will be omitted.

EFFECTS OF THE INVENTION The present invention is configured as described above, and the stirring head 7 is penetrated to a predetermined depth of the ground, and the fluid pressure cylinder 6 is contracted or extended while the fluid pressure cylinder 6 is contracted or extended while injecting the improving material from the stirring head 7. By increasing the speed, it is possible to make the injection amount of the improving material substantially uniform. Further, by stopping the rising for a certain period of time and injecting the improving material, it is possible to obtain a good improved columnar body in which the improving material is sufficiently injected.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is a schematic view of a ground improvement device, FIG. 2 is a view showing an outline of wiring of the device, and FIG.
FIG. 4 is a schematic view of the device for detecting the position of the drive device with respect to the lifting member of the device, FIG. 4 is a block diagram showing the logic circuit of the device, FIG. 5 is a front view of the main part of the device, and FIG. The figure is a partial cross-sectional view of the stirring head used in the apparatus. 1 ... Leader 2 ... Elevating member 3 ... Wire 4 ... Vertical movement device 5 ... Drive device 6 ... Fluid pressure cylinder 7 ... Stirring head 8 ... Pipe 9 ... Nozzle 10 ... Supply device 11 ... Actuator 12 ... Depth detector 13 ... Position Detection device 14 ... Setting device 15 ... Automatic / manual switching switch 16 ... Logic circuit 17 ... Arithmetic circuit 18 ... Comparator 19 ... Timer circuit 20 ... Actuation circuit

Claims (2)

[Claims] 1. An elevating member movably provided on a reader provided in an up-down direction; an up-and-down moving device for hoisting and lowering the elevating member with a wire; a fluid pressure cylinder having a drive device provided on the elevating member; A pipe provided with a stirring head at the tip of the drive unit; a nozzle provided on the stirring head; a supply device for an improvement material provided in communication with the pipe; provided in communication with the fluid pressure cylinder A ground improvement device comprising a hydraulic cylinder actuator. 2. An elevating member movably provided on a reader provided in an up-down direction; an up-and-down moving device for hoisting and lowering the elevating member with a wire; a fluid pressure cylinder having a drive device provided on the elevating member; A pipe provided with a stirring head at the tip of the drive unit; a nozzle provided on the stirring head; a supply device for an improvement material provided in communication with the pipe; provided in communication with the fluid pressure cylinder An operating device for the fluid pressure cylinder; a depth detecting device for detecting the underground depth of the stirring head; a position detector for detecting the position of the driving device with respect to the elevating member; a position detector for setting the position detector and a setting device for setting a numerical value; And a logic circuit connected to the automatic or manual switching switch and connected to the actuating device;
A ground improvement device comprising an arithmetic unit, a comparator, and a timer circuit provided in the logic circuit.