JP3126909B2 - Automatic soil augmentation control method of soil cement column in foundation ground - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a soil cement column in a soil cement synthetic steel pipe pile method or the like, and more particularly, to a construction management for controlling an injection amount of cement milk supplied to the soil cement column. The present invention relates to a system and a control method thereof. Here, the soil cement synthetic steel pipe pile excavates the ground with an earth auger, supplies the solidified material into the excavation hole, mixes and mixes with the soil at the current position by the stirring blade at the tip of the earth auger as it is, into the ground A steel pipe having a diameter smaller than that of the soil cement column is inserted into the formed columnar soil cement, so-called soil cement, and is integrated with the steel tube by hardening of the soil cement column. Usually, ribs are provided on the outer peripheral surface and the inner peripheral surface of the steel pipe to ensure integration with the soil cement column. Thus, this is a form of foundation pile aiming at the reduction of construction waste and the improvement of the working environment in response to the suppression of construction waste and the labor shortage. In the present invention, it is not limited to only the soil cement synthetic steel pipe pile construction method, other construction methods involving the creation of soil cement columns carried out during the construction method, for example, an underground continuous wall construction method,
Naturally, application of the ground improvement method is also performed.

[0002]

2. Description of the Related Art In the construction of a soil cement column in the conventional soil cement synthetic steel pipe pile method, various control means are being used to control the amount of cement milk to be injected. That is, as one of the control means,
A system is adopted in which the column forming speed is constantly detected, and the cement milk injection pressure is linearly controlled based on the comparison value based on a comparison with the set column forming speed. However, according to this method, the injection pressure frequently changes in response to the change in the column forming speed, and an interference action occurs between the two, sometimes causing a hunting phenomenon, resulting in poor responsiveness. In addition, if the sensitivity is made slower in this control method, the tracking performance is deteriorated,
As a result, the response is poor. Therefore, some conventional control systems are not always adapted to the automatic control of cement milk in the construction of this type of soil cement column mainly for on-site construction.

[0003]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems of the prior art, and has excellent responsiveness and can control the supply amount of cement milk suitable for on-site construction. It is an object of the present invention to obtain an automatic control method for forming a soil cement column on a foundation ground.

[0004]

Means for Solving the Problems In order to achieve the above-mentioned object, the method of the present invention for automatically forming a soil cement column on a foundation ground employs the following technical means. That is, in the first invention, as described in claim 1, a consolidated material such as cement milk is supplied into a hole excavated in the ground by an excavator, and the excavator is provided with a current position by a stirring blade at the tip of the excavator. In the method of mixing and stirring with soil and soil to form a soil cement column in the ground, at least the construction data of the depth of column formation and the amount of cement milk injection at the tip of the excavator is detected by a detection device, and the detection data Based on the comparison, the measured cement milk injection amount and the set milk injection amount are compared, and the injection amount of the cement milk supply device is controlled based on the comparison value, and the depth is divided into depth sections in small distance units,
In the unit depth section, a constant supply of cement milk is made, and when changing the unit depth section, setting of the setting milk injection amount of cement milk is performed by incorporating correction of excess or deficiency in the previous section. I do. According to a second aspect of the present invention, as set forth in claim 2, a consolidation material such as cement milk is supplied into a hole excavated in the ground by an excavator, and the sediment at the current position is directly supplied by a stirring blade at the tip of the excavator. In the method of forming a soil cement column in the ground by mixing and stirring, at least, the construction data of the column depth and cement milk injection amount at the tip of the excavator is detected by a detection device, and based on the detection data, Compare the measured cement milk injection amount with the set milk injection amount, control the injection amount of the cement milk supply device based on the comparison value, and set the column forming speed as the column forming depth per unit time to a constant width speed. Areas are divided, and the cement milk injection amount per unit time is assigned so that the same injection amount per unit depth corresponds to each speed area. It is determined whether or not to continue in the area for a predetermined time, and if it is within the above-mentioned predetermined time, the actually measured column velocity is maintained, and if it exceeds the above-mentioned predetermined time, the area is changed to a design speed area corresponding to the actually measured column velocity. It is characterized by doing.

(Action) In the first invention, the depth section of the small distance unit functions as a check section of the supply amount of cement milk, and the responsiveness between the column forming speed and the supply amount of cement milk is reduced.
The setting accuracy of the cement milk supply amount is improved. In the second invention, the cement milk injection amount is made variable without changing the current column forming speed, and as a result, the expected cement milk injection amount is secured in the control target section. Thereby, the responsiveness between the column forming speed and the cement milk supply amount is reduced, and the setting accuracy of the cement milk supply amount is improved.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an automatic soil cement column forming control method according to the present invention. (Configuration of Embodiment) FIGS. 1 to 17 show a construction management system in a soil cement synthetic steel pipe pile method according to one embodiment.
That is, FIG. 1 shows the entire configuration of the construction management system, FIGS. 2 to 5 show the partial configuration of the machine part, and FIGS. 6 to 17 show the software configuration. In the figure, E is the ground and P is the soil cement column.

FIG. 1 shows a schematic configuration of a construction management system in a soil cement synthetic steel pipe pile method. This system is a construction machine S for constructing a soil cement column P on a ground E.
And a cement milk supply device M that supplies cement milk to the construction machine S, and includes a detector and a control device arranged in each part of the construction machine S and the cement milk supply device M. The control device specifically adopts a “construction management device”, and processes the work instruction device 100, the output signals of the work instruction device 100, and the signals output from the various detectors according to a predetermined program. A processing device 110,
The display device 120, the data storage device 13
Contains 0.

[0008] The construction machine S is a vertically standing reader 1
A, a construction machine main body 1 that has a wire 1B that is suspended along the leader 1A and that can be wound up and rewinded by a winch, and that can be moved by a crawler 1C, and excavation mounted on the construction machine main body 1. A drive unit 3 guided along the reader 1A as the stirring device 2, a rotation shaft unit 4 which rotates by receiving rotation of the drive unit 3, a drilling blade and a stirring blade attached to a lower end of the rotation shaft unit 4; And a digging / stirring unit 5 having The cement milk supply device M includes an automatic batcher plant 7 and an automatic cement milk supply device 8. Among them, the automatic batcher plant 7 has a function of switching the mixing of the water / cement ratio, and the automatic cement milk supply device 8 supplies the cement milk with a predetermined amount to the hose 9.
Through to the construction machine S.

However, this system is applied to a construction mode in which a large number of soil cement columns P are cast in a ground area having a certain extent.

Hereinafter, the configuration of each part will be described in detail. The construction machine main body 1 comprises a vertically erected leader 1A, a wire 1B suspended along the leader 1A and capable of being wound and rewinded by a winch, and is provided by a crawler 1C. It is movable. As the construction machine main body 1, a known construction machine is used. The construction machine body 1 has a "construction management device"
Is mounted and operated by an operator.

[0011] Drilling and stirring device 2 excavating and stirring device 2, the driving unit 3 is guided along the reader 1A, rotation shaft (or the rotating rod) 4 which rotates by receiving the rotational drive of the drive unit 3, the An excavating / stirring unit 5 mounted on the lower end of the rotating shaft unit 4 and having stirring blades. The drive unit 3 drives the rotary shaft unit 4 and the excavation / stirring unit 5, which are the main components of the excavation / stirring unit 2, to rotate.
Supply port for cement milk supply to the plant. FIG. 2 shows a schematic configuration of the driving unit 3. That is, the casing 12
A guide jib 13 that engages with and slides on the reader 1A is attached to the back of the casing. An electric motor 14 is mounted inside the casing 12, and is attached to the rotating shaft 4 via a reduction gear 15 and a gear mechanism 16. Transmit torque. An injection device 17 is mounted on the upper part of the rotating shaft portion 4 and a cement milk supply device M
Accept supply of cement milk from Rotating shaft part 4 Rotating shaft part 4 rotates by receiving rotational driving force from driving unit 3
In addition, a hollow tube is formed, and cement is provided in the hollow portion 4a.
Milk passes. That is, the injection device 17 installed at the upper end of the rotating shaft 4 is free to rotate with the rotating shaft 4 and is connected to the hose 9 that is connected to the cement milk supply device M. The rotating shaft portion 4 is appropriately extended with a unit length.

[0012] Drilling and stirring portion 5 excavation and stirring portion 5, as shown in FIG. 3, the rotating shaft portion 4
A drilling wing 20 having a drilling bit 20a protruding therefrom is disposed at a lower end thereof, and four stirring blades 21 are disposed above the drilling wing 20. The hollow portion 4a of the rotary shaft portion 4 is provided.
The cement milk is discharged from the discharge port 5a communicating with the cement milk.
In the illustrated example, the cement milk discharge port 5a is provided below the stirring blade 21. However, a mode in which a cement milk discharge port 5b (shown by a broken line) is provided above the stirring blade 21 can be adopted. That is, in the case of only the cement milk discharge port 5a, a W-shaped construction mode described later is adopted, and in the case where the cement milk discharge ports 5a and 5b are provided, a V-shaped construction mode described later is adopted. In addition, a valve body is added to the discharge ports 5a and 5b, and the switching operation is performed by the operation of the valve body. FIG. 4 shows another embodiment of the excavation / stirring unit 5A. In the excavating / stirring unit 5A, the rotating shaft part 4 has a double pipe structure of an inner pipe 23 and an outer pipe 24, the inner pipe 23 protrudes from the lower end of the outer pipe 24, and the inner pipe 23 has , A lower stirring blade 21A and a cement milk discharge port 5a are disposed, and an outer pipe 24 is disposed with an upper stirring blade 21B. The lower stirring blade 21A and the upper stirring blade 21B have the same configuration.

Automatic Batcher Plant 7 The automatic batcher plant 7 performs the automatic metering of cement and water, performs mixing at a predetermined mixing ratio, and has a function of switching between poor mixing and rich mixing. FIG. 5 shows a schematic configuration of the automatic batcher plant 7, a mixing tank 30 for mixing and stirring the measured cement and water, and a first poor mixing compound for stirring the cement milk supplied from the mixing tank 30. An agitator tank 31 and a second agitator tank 32 for rich mixture are provided. The mixing tank 30 is branched into first and second agitator tanks 31 and 32 via switching valves 33a and 33b. First agitator tank 31 and second agitator tank 3
It conducts to the supply device 8 via the two to three way valve 34. The three-way valve 34 is operated by pneumatic drive, and its open / closed state is sent to the processing device 110 as an electric signal, and performs an opening / closing operation in response to an instruction from the processing device 110.

Automatic cement milk supply device 8 The automatic cement milk supply device 8 is mainly composed of an inverter pump, and sends a predetermined amount of cement milk to the construction machine S via a hose 9. In FIG. 5, reference numeral 36 denotes the inverter pump, which specifically employs a triple plunger pump. Cement milk is sent from the inverter pump 36 to the construction machine S via the hose 9 at a predetermined injection amount. The length of the hose 9 is set to a length corresponding to the target ground area, and its capacity is known. Inverter pump 36 is driven at 0.0 to 120.0 Hz.
The actual frequency of the inverter pump 36 is sent to the processing device 110, and receives a predetermined frequency in response to an instruction from the processing device 110.

The work management system construction management apparatus is installed in construction machine body 1, a work instruction unit 100, for processing in accordance with a signal outputted from the output signal of the working instruction unit 100 detector to a predetermined program A display device 120 and a data storage device 130. The display device 120 employs a touch panel to display a construction state and to instruct an operation by touch input. The construction management device has at least various functions of display of management items, that is, detection data, display of construction status, confirmation of a support layer, recording of construction data, and an alarm device. The detection data includes the excavation depth, the cement milk injection amount, the cement milk injection (discharge) pressure, the excavation current value, the stirring current value, the inverter frequency, the state of the switching valve, and the like. These detected data are sent to the processing unit 1 every second.
It is taken into 10. Excavation depth: rotation of the construction machine S in the excavation / stirring device 2
Output from a depth gauge that monitors the displacement of the lower end of the shaft 4
Obtained from the signal. It is measured with the pulse count value. Usually, 0.0-50.0 m is taken. Cement milk injection amount: Detected by an electromagnetic flow meter linked to the automatic cement milk supply device 8 in the cement milk supply device M. Usually 0.0 to 400.
Take 0 l / min. Cement milk injection (discharge) pressure: detected by an injection pressure gauge mounted on the cement milk automatic supply device 8 in the cement milk supply device M. Usually 0.0
Take 100.0 kg / cm ² . Excavation current: detected by an excavation ammeter mounted on the drive unit 3 that drives the excavation rotary shaft of the construction machine S. Usually, 0.0 to 600.0 A (ampere) is taken. Stirring current: Detected by a stirrer ammeter attached to the drive unit 3 that drives the rotating shaft for stirring in the construction machine S. Usually, 0.0 to 600.0 A is taken. Inverter frequency: The output value of the inverter pump 36 as a cement milk discharging device is taken. Usually 0.0
Taking 120.0 Hz. Switching valve state: The switching state of the switching valve of the automatic batcher plant 7, that is, the three-way valve 34, is detected.

Detecting device The detecting device includes a depth gauge, an electromagnetic flow meter, an injection pressure gauge,
Drilling ammeter, stirring ammeter, etc. are adopted. Depth gauge: Measures the depth of the rotating rod in the excavation / stirring device 2. Detect as pulse display. Electromagnetic flowmeter: installed at the end of the cement milk injection hose 9 connected to the cement milk discharge pump 36,
Detect the amount of cement milk injected. Injection pressure gauge: installed at the end of the cement milk injection hose 9 connected to the cement milk discharge pump 36,
Detect the injection pressure of cement milk. Drilling ammeter: mounted on the drive unit 3 of the construction machine S and detects a drive current of the drive unit 3 that drives the rotating rod 4. Stirring ammeter: attached to the driving unit 3 of the construction machine S, and detects a driving current of the driving unit 3 that drives the stirring unit 5.

Construction management procedure The soil cement columns P are constructed and constructed in a ground area having a certain extent by using the above-mentioned components. The construction management procedure proceeds according to a program stored in the ROM of the processing device 110. For this reason, a “scaling value setting program” and a “reference value setting program” are prepared based on the “construction management program” centered on the “milk injection amount control program”. Further, in order to execute these programs, various reference values, speed area patterns, pile patterns, and inverter values for the inverter pump are determined as index values. FIG. 6 shows the configuration of a program and the flow of data in the construction management system.
Here, the detection items are the above-mentioned excavation depth, cement milk injection amount, cement milk injection (discharge) pressure, excavation current,
Stir current and inverter frequency are taken. Further, the screen display A performs a digital display and a graph display, and the screen display B displays a reference value and a scaling value.

<Reference values> In proceeding with the construction management procedure, the following various reference values are first determined as index values required for the construction management: (1) First lower limit injection amount (2) Second Next lower limit injection amount (3) Upper limit drilling current value (4) Upper limit stirring current value (5) Current value upper limit reaction time (6) Upper limit injection pressure (7) Injection pressure reaction time (8) Stationary stirring time (9) Hose capacity (Blending correction value) (10) Estimated N value reference value (11) Idle current value (12) Support layer calculation coefficient. Of the above, (1) to (8) form the basis. FIG. 7 shows a reference value setting screen. The contents of these reference values are as follows. (1) Primary lower limit injection amount: For example, 99% is adopted. If the instantaneous milk inflow amount falls below the first lower limit injection amount, a first alarm is issued. (2) Secondary lower limit injection amount: For example, 90% is adopted. If the instantaneous milk inflow amount falls below this second lower limit injection amount, a second alarm is issued. (3) Upper limit excavation current value: For example, 450A is adopted. When the instantaneous excavation current value exceeds this upper excavation current value continuously for the current value upper limit reaction time or longer, an alarm is issued. (4) Upper limit stirring current value: 350 A is adopted, for example. If the instantaneous value of the stirring current value continuously exceeds the upper limit stirring time for the current value upper limit reaction time, an alarm is issued. (5) Current value upper limit reaction time: This is the reaction time until the alarm output of the excavation stirring current value, and takes, for example, 1 second. (6) Upper limit injection pressure: Take, for example, 20 kg / cm ² . When the instantaneous injection pressure value exceeds the upper limit injection pressure continuously for the upper limit injection pressure reaction time or longer, an alarm is issued. (7) Injection pressure reaction time: The reaction time until the injection pressure alarm is output, for example, 1 second. (8) Static stirring time: for example, 60 seconds is taken. In the stationary stirring section, when the stationary stirring time is exceeded, the process proceeds to the next depth section. (9) Hose capacity (compensation correction value): For example, 200 l (l) is taken. When the composition changes from the poor composition to the rich composition, the composition is switched from the depth that is faster by the hose capacity. Mixing change depth = Section shift depth ± (Hose capacity / Poor mix design injection amount / Poor mix setting speed) However, when changing from a rich mix to a poor mix, processing is performed with a value of 1/2 of the hose capacity. (10) Estimated N value reference value: For example, 48 is adopted. If the estimated instantaneous N value exceeds the estimated N value reference value during the penetration, an alarm (safe side) is issued. Estimated N value (N): N = K (Ad−Ao) √D where N: estimated N value, K: estimated N value reference value, Ad: excavation current value (A), Ao: idling current value ( A), D: Depth (m) (11) Idling current value: It is a digging current value when the vehicle is idling before the penetration and on the ground, for example, 80 A is taken.

<Speed area pattern and pile pattern> In addition to the above reference values, "speed area pattern" and "pile pattern" are set as index values. The setting of the speed region is performed by appropriately dividing the travel distance (meter) per unit time (minute), that is, the speed (meter / minute) into regions, and injecting cement milk (liter / liter) corresponding to each speed region. Minutes). The velocity region and the injection volume are in a proportional relationship. Poor blending and rich blending are determined by the correspondence between the velocity region and the injection amount. FIG. 8 shows a setting screen of the speed area pattern. In the example shown in FIG. N with 1 and wealth
o. 2 shows an example of two patterns. FIG. 9 is a graph showing the correspondence between the speed region and the amount of cement milk injection. In the present embodiment, the speed is set to 1.00 m / min and 0.05 m /
Minutes in the speed range (0.95 to 1.05 m /
140 liters / min. The velocity region is delimited every 0.10 m / min and changes at a 14 l / min injection rate. 0.
60 liters / at a speed of 28-0.33 m / min
Per minute, where the velocity region changes every 0.05 m / min, whereas it changes at a 10 l / min injection rate. FIG. 8 shows one pattern of a poor mixture and one pattern of a rich mixture.
Prepare a pattern.

Setting of Pile Pattern The pile pattern is determined by inserting a speed region pattern in accordance with the depth section in the pile formation by the construction machine. FIG. 10 shows a setting screen of the pile pattern. That is, on this screen, the depth section speed area pattern number setting speed design injection amount construction type pattern (W type / V type) is input. FIG. 11 shows a process of forming a soil cement column P in the ground formed based on the set pile pattern. In the illustrated example, a W-type soil cement column molding method is shown, and a stirring unit 5 having a cement milk discharge port 5a shown in FIG. 3 is used.
In the example of FIG. No. 1, No.
No. 2 corresponds to FIG. 0 is cement
There is no injection. In FIG. 3, two cement spouts
When using the stirring unit 5 having the outlets 5a and 5b, the V type
Selected. In the case of the V type, no. 3, N
o. 4, No. 6-No. 9 is omitted, and construction is performed quickly.

<Inverter Value> In this embodiment, an inverter pump is used. In order to control this inverter pump, a speed region determination time (increase direction) a speed region determination time (decrease direction) injection amount reference region (increase direction) injection amount reference region (decrease direction)
Startup amplification rate Startup amplification time Minimum injection amount Various amounts of injection pressure correction coefficient are determined. FIG. 12 shows this inverter value setting screen, on which the above-mentioned respective set values are inputted. Hereinafter, the contents of these set values will be described. Speed region determination time (increase direction): For example, 5 seconds is taken. If the current speed (instantaneous value) deviates from the applicable speed range to the higher speed continuously for more than this speed range determination time during construction, the pump moves to the next speed range and changes the pump discharge rate. Do it automatically. Speed region determination time (downward direction): Takes 5 seconds, for example. If the current speed (instantaneous value) deviates from the applicable speed range to the lower speed continuously for more than this speed range determination time during construction, the pump moves to the next speed range and changes the pump discharge rate. Do it automatically. Injection amount reference region (increase direction): For example, 10% is adopted. When checking the injection amount at every 50 cm depth during construction, the design injection amount and the actual injection amount are compared, and if the actual injection amount exceeds (design injection amount x (1 + injection amount reference area / 100)), the following Adjust the pump discharge so that the excess is subtracted in the 50 cm section. The excess is calculated by the following formula: excess = actual injection amount− (design injection amount × (1 + injection reference region / 100)) Injection reference region (downward direction): Take 5%, for example. When checking the injection amount at every 50 cm depth during construction, the design injection amount and the actual injection amount are compared, and if the actual injection amount is less than (design injection amount x (1-injection amount reference area / 100)), the next Adjust the pump discharge amount to add the shortage in the 50 cm section of. The calculation of the shortage is given by the following equation: shortage = design injection amount−actual injection amount Startup amplification factor: Take, for example, 130%. When increasing the pump discharge amount, an instruction is sent to the inverter pump to output the pump discharge amount multiplied by the start amplification factor during the start amplification time. After the startup amplification time, the pump returns to the normal pump discharge amount. The calculation of the pump discharge command amount at the time of startup amplification is given by the following equation: Pump discharge command amount = pump discharge amount + (increase × startup amplification rate / 100) Startup amplification time: Time for performing startup amplification. Take 5 seconds. Minimum injection volume: The minimum setting volume of the pump discharge instruction,
For example, take 40 liters / minute. If the set pump discharge amount falls below the minimum injection amount due to re-strike, the minimum injection amount becomes the pump discharge amount. Injection pressure correction coefficient: a correction coefficient for automatic pump control, for example, 303.

Data Processing Method When executing the program of the present construction management, data processing is performed according to the following rules. The input data is captured from the input of the pile number input end signal to the input of the measurement end signal, and the data is calculated and displayed every second. The analysis data is stored between the time when the measurement start signal is input and the time when the measurement end signal is input. The excavation speed is calculated as the difference in excavation depth. The transition of the depth section is automatically performed under the following conditions. a. If the traveling direction of the next depth section is the same, the transition automatically occurs when the excavation depth exceeds the set depth. However, if the excavation depth enters the depth section before the transition due to backlash or the like after the transition, the depth section is not changed. b. If the traveling direction of the next depth section is different, if the excavation depth reaches the set depth and the traveling direction changes, and is displaced by a predetermined unit distance (for example, 10 cm) or more, the operation automatically shifts to the next depth section. c. In the depth section before the stationary stirring section, when the excavation depth reaches the set depth and stays within the predetermined distance (+10 cm) for a predetermined time (for example, 10 seconds) or more, the apparatus automatically shifts to the stationary stirring section. d. In the depth section of the stationary stirring section, when the set stationary stirring time is satisfied and the excavation depth is raised by a predetermined distance (10 cm) or more, the operation automatically shifts to the next depth section. The elapsed time starts counting when a measurement start signal is input, and ends counting when a measurement end signal is input.

Milk injection amount control method The milk injection amount control, which is the main part of this construction management procedure, is performed in the following manner. The milk injection amount control (inverter frequency control) is performed based on the excavation speed based on the speed region pattern of the pile pattern. The change (control) of the milk injection amount is performed when the current speed region deviates from the current speed region by the speed region determination time for the time or more. The set milk injection amount and the actual milk injection amount are compared for each predetermined depth (for example, 50 cm), and when the actual milk injection amount exceeds or falls below the injection amount reference region of the set milk injection amount, the injection during the next predetermined depth is performed. The injection is performed with the injection amount obtained by adding the insufficient amount.
The start-up adjustment at the start of the pump is adjusted by setting the start amplification factor and the start amplification time. Switching of compounding valve
Is automatically performed from the setting and blending of the pile pattern of the reference value.
If the mix changes at the same time when moving to the depth section,
Calculated from the amount (compensation correction value) and the design milk
Switch the blending valve first at the given depth.

Creation of the soil cement column The reference values, speed area patterns and pile patterns above the above are set, and according to the data processing method and the milk injection amount control method, the soil cement column P is created according to the following procedure. Will be implemented. FIG. 13 shows a ground area to be constructed, and FIG. 14 shows a geological map of the ground. Prior to this construction, pre-boring is performed in this ground area, and the hardness (N value) of the formation is measured. As shown in the drawing, a cement milk supply device M is arranged facing the target ground, and cement milk is pumped from the cement milk supply device M to the construction machine S via a hose 9 having a predetermined length. This hose 9
The length of the hose determines the hose capacity as a blending correction value. The construction machine S moves sequentially and constructs the soil cement pillar P (see arrow A). In the construction, the creation of the soil cement columns P1 and P2 is completed, and the construction is in the creation process of P3. Each of the soil cement columns P is composed of a poor compounding portion at the upper portion and a rich compounding portion as a solidification portion at the lower end.

FIG. 15 is a flowchart showing the outline of the construction management. In other words, the gist of this flow is to display and store the construction status on a monitor screen based on the data obtained every second from the detector, and at the same time, control the milk injection amount from the set milk injection amount, excavation speed and injection pressure. And outputs an alarm when each monitoring item deviates from the set value.

The construction management flow will be described below with reference to the flowchart of FIG. (Step S1) Pile number / pile pattern number is input. At the time of input, a reference value table of the first layer for control and determination depths is created according to the already registered pile pattern numbers. The registration of the pile pattern includes a set injection amount for each depth section, a set speed, an injection amount for each speed region, and the like. When the reference value table is created, an inverter set value and the like, which are common reference values for each pile, are read. (Step S2) The construction machine S is moved to the determined position, the depth is set to 0.0 m, and the management device side is adjusted to the actual depth. (Step S3) The measurement start button is pressed to start. Thereafter, sampling and processing are performed every second. (Step S4) The measurement value is read by the detection device, and the data is processed for processing. The detection device is the depth meter, electromagnetic flow meter,
An injection pressure gauge, drilling ammeter, stirring ammeter is used, and the detection data is the drilling depth, cement milk injection amount,
It takes cement milk injection (discharge) pressure, drilling current, stirring current, and inverter frequency. (Step S5) responsible for determining whether there is a transition in the depth interval, proceeds to step S6 when moving, in the case of directly stearate
Proceed to step S7 . (Step S6) When the depth section shifts, a reference value table for that layer is created, and then the process proceeds to step S7 . (Step S7) The actual value obtained from the measured value is compared with a reference value. Thereafter, the process proceeds to step S8 . (Step S8) to determine whether blending switching depth, proceeds to step S9 in the case of switching the depth, in the case of directly step S
Go to 10 . (Step S9) If the determination at step S8 has reached the depth at which the composition is to be switched, the composition is switched. In response to the command to switch the mixture, the switching valve is operated to switch between the poor mixture and the rich mixture. (Step S10) The injection amount is automatically controlled in this step.
That is, when the injection amount check section (50 cm) is switched from the result of step S7 , the set injection amount corrected for the excess or deficiency in the previous section is calculated. When the current velocity region is deviated, the set injection amount to be instructed to the pump is set from the setting injection with the registered injection amount in the corresponding speed region. Calculate the set inverter frequency on the pump side from the calculated set injection volume.
Output. (Step S11) The current situation is displayed on the CRT screen. The display screen includes a digital screen (1) and a graph screen (2). Then
Proceed to step S12 . (Step S12) It is determined whether or not there is an alarm output. If there is an alarm output, the process proceeds to step S13.
Proceed to step S14 . (Step S13) The alarm output is determined by the determination in step S12 ,
If the reference value is not satisfied based on the result of step S7 , or if there is any other event, an alarm buzzer sounds and / or an alarm is displayed on a CRT screen. (Step S14) It is determined whether or not the measurement is completed. If the measurement is not completed, the process returns to step S4. If the measurement is completed, the process returns to step S15.
Proceed to. (Step S15) When the measurement end button is pressed, the daily report data and the analysis data are stored in a file, and the input of the pile pattern number of the next pile is awaited. (Step S16) It is determined whether or not the construction of the next pile is to be continued. If the construction is continued, the process returns to step S1 .

Automatic control of milk injection amount (step S1)
0, “injection amount automatic control subroutine”) is shown in FIG.
It is performed with the following flow. (Step S20) Data necessary for automatic injection amount control, that is, four elements of milk injection amount, injection pressure, excavation depth, and excavation speed are extracted from the measured data. (Step S21) It is determined whether or not there is a pressure abnormality. If the pressure is not abnormal, the process proceeds to step S22. If the pressure is abnormal, the process proceeds to step 32. (Step S22) to determine whether there is a change in the depth interval, if the change is passed to step S23, step in the absence of changes
Proceed to S24 . (Step S23) When the depth section is changed in step S22 , and when the injection amount check section (50 cm) is switched, the set injection amount for the set speed in which the excess or deficiency in the previous section is corrected is calculated. (Step S24) If there is no change in the depth section in step S22 , the current applicable speed region is calculated. Then, step S25
Proceed to. If the current speed region is continuously deviated for the set time or more, the process moves to the next speed region. (Step S25) It is determined whether or not the speed area section has been changed.
Proceeds to step S26, step S in the case where there is no change
Proceed to 27 . (Step S26) If the speed region section is changed in step S25 , the speed region is reset. (Step S27) If there is no change in the speed region section in step S25, a set injection amount is calculated from steps S23 and S24 when the pump currently needs to discharge. Thereafter, the process proceeds to step S28 . ( Step S28 ) It is determined whether or not the start amplification process is performed. If the amplification process is performed, the process proceeds to step S29 . If the amplification process is not performed, the process proceeds to step S30 . (Step S29) When the set frequency in step S27 changes to a value larger than the previous set frequency, a value obtained by multiplying the start amplification factor and the set frequency so as to reach the set injection amount faster is set as the set frequency. (Step S30) From the result of step S27 and the injection pressure, an inverter set frequency for giving an instruction to the pump is calculated. (Step S31) The set frequency is output to the inverter of the pump. (Step S32) If it is determined in step S21 that there is a pressure abnormality, and if the injection pressure continuously exceeds the set pressure value for a set reaction time or longer, the set injection amount is reduced by １ ／.
When the pressure falls below the set pressure value, the control returns to the normal control again. (Step S33) An alarm process is performed.

The present invention is not limited to the above embodiment, and various design changes can be made within the scope of the basic technical concept of the present invention.

[0029]

According to the method of automatically controlling the formation of soil cement columns on the foundation ground according to the present invention, the column forming speed is kept constant and the injection of the cement milk in accordance with the execution speed is controlled. Responsiveness between the supply of cement milk and the supply amount of cement milk is reduced, and the setting accuracy of the supply amount of cement milk is improved.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of a construction management system showing one embodiment of a method for automatically forming soil cement columns on a foundation ground according to the present invention.

FIG. 2 is a configuration diagram of a drive unit that is a component of the construction machine.

FIG. 3 is a configuration diagram of a stirring unit that is a component of the construction machine.

FIG. 4 is a configuration diagram of another embodiment of the stirring unit.

FIG. 5 is a schematic configuration diagram of a cement milk supply device.

FIG. 6 is a flowchart of a program configuration and data in the construction management system.

FIG. 7 is an exemplary diagram of a reference value setting screen.

FIG. 8 is an exemplary diagram of a speed area setting screen.

FIG. 9 is a diagram showing a relationship between a velocity region and an injection amount.

FIG. 10 is a view showing an example of a pile pattern setting screen.

FIG. 11 is a diagram showing a relationship between a depth and a set speed.

FIG. 12 is an exemplary diagram of an inverter value setting screen.

FIG. 13 is a plan view of the construction target ground.

FIG. 14 is a cross-sectional view of the construction target ground.

FIG. 15 is a flowchart showing a construction management procedure of the construction management system.

FIG. 16 is a flowchart showing a procedure of automatic injection amount control.

FIG. 17 is a flowchart showing a procedure of measurement and setting.

[Explanation of symbols]

S: Construction machine, M: Cement milk supply device, P: Soil cement column, 1: Construction machine body, 2: Excavation / stirring device

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kan Kitamura 2-3-11 Kanda Surugadai, Chiyoda-ku, Tokyo Inside Konoike-gumi Tokyo Main Store (56) References JP-A-6-299538 (JP, A) JP-A-Hei 5-125720 (JP, A) JP-A-6-2999539 (JP, A) JP-A-1-131716 (JP, A) JP-A-62-242012 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 3/12 E02D 5/46

Claims (4)

(57) [Claims] An excavator feeds a cement material such as cement milk into a hole excavated in the ground, mixes it with the earth and sand at the current position by a stirring blade at the tip of the excavator, and directly mixes the soil cement into the soil. In the method of forming a column, at least construction data of a column depth and a cement milk injection amount at a tip portion of the excavator is detected by a detection device, and based on the detected data, an actually measured cement milk injection amount and a set milk injection are detected. Control the injection amount of the cement milk supply unit based on the comparison value, and divide the depth into small distance unit depth sections. A predetermined amount of cement milk corresponding to the column speed is supplied, and when changing the unit depth section, the correction of excess or A method for controlling the automatic formation of a soil cement column, wherein the setting of the milk setting amount of the luk is performed. 2. A cementing material such as cement milk is supplied into a hole excavated in the ground by an excavator and mixed with the earth and sand at the current position by an agitating blade at the tip of the excavator as it is. In the method of forming a column, at least construction data of a column depth and a cement milk injection amount at a tip portion of the excavator is detected by a detection device, and based on the detected data, an actually measured cement milk injection amount and a set milk injection are detected. In addition to controlling the injection amount of the cement milk supply device based on the comparison value, the casting speed as the casting depth per unit time is divided into speed regions with a fixed width, and each speed region is The cement milk injection amount per unit time is allocated to achieve the same injection amount per unit depth, and it is determined whether or not the measured column speed continues in the set speed region. A method for controlling the automatic formation of a soil cement column, wherein, if the speed is outside a speed range for a predetermined time, the speed is changed to a design speed range corresponding to the actually measured column speed. 3. The method for automatically controlling a soil cement column according to claim 2, wherein the depth is divided into unit depth sections, and the column depth corresponds to the column forming speed per unit time in the unit depth section. When a predetermined amount of cement milk is supplied and the depth section of the unit is changed, the correction of the excess or deficiency of the previous section is incorporated to set the setting milk injection amount of the cement milk, and each depth section A method for automatically forming and controlling a soil cement column, wherein a speed region is assigned to each of them. 4. The method for automatically controlling a soil cement column according to claim 2, wherein the set injection amount of the cement milk is changed from a poor mixture setting to a rich mixture setting.
When moving to the
A method for automatically forming a soil cement column, wherein the composition is switched from a depth that is as fast as the hose capacity .