JP5446005B2 - Submerged mound compaction method and compaction device - Google Patents

Description

  The present invention relates to a submerged mound compaction method and compaction device using a sand pile construction ship.

  In recent years, for the construction of large container berths, sea surface disposal sites, artificial airport islands, etc., large-scale deployment of port structures to the offshore has progressed, but breakwaters and revetment structures built in deep waters, etc. Is constructed on a mound (hereinafter also referred to as “underwater mound”), which is a mixed levee with a large depth and a large thickness, mostly rubble. For this revetment structure constructed on the artificially constructed mound, further improvement in earthquake resistance and durability is required, and for the improvement, the bottom mound is compacted, It is essential to make a high-standard mound that can withstand large deformations.

  In the past, the compaction of the bottom mound, which has been performed by divers, has recently shifted to mechanical leveling from the viewpoint of further improving work efficiency and safety. However, at the beginning of the introduction of mechanical leveling, concrete blocks and weights were lifted by crane ships and compacted by naturally dropping them to the bottom of the water. It has been pointed out that due to the water cushion action and the like, the compaction energy is significantly reduced, and further, the weight is misaligned, and a sufficient mound compaction effect cannot be obtained. In order to solve this problem, the sand pile formation ship 10 shown in FIGS. 8 and 9 is introduced into the mechanical leveling of the bottom mound, and the sand pile formation hollow pipe 12 of the sand pile formation ship 10 is installed at the lower end portion. It is possible to obtain a dense and robust bottom mound M by attaching a tamper (tamping plate) 14 and creating the bottom mound M by vertical vibration of a vibro hammer 16 installed in the hollow tube head. (For example, see Patent Documents 1, 2, and 3). In addition, in FIG. 9, the part shown with the code | symbol Ig is the improved ground where suppression of the ground subsidence was aimed at, and the bottom mound is formed on this improved ground Ig by the sand pile formation hollow pipe 12 of the sand pile formation ship 10. M will be added.

Japanese Patent No. 2666321 Japanese Patent No. 2689002 Japanese Patent No. 2791913

By the way, since most of the bottom mound is a composite levee made of rubble, the behavior of the mound during compaction by mechanical equalization of the bottom mound is not simple, and it is not easy to grasp the deformation characteristics due to its subsidence. For example, when considering the entire bottom mound that supports the top load , such as caisson weight, it is preferable if it is possible to easily measure the ground reaction force of the bottom mound in a flat plate loading test. A load testing device that measures the entire mound is not practical. Even if a load block is manufactured and a measurement test of a mode in which a load exceeding the upper load is forcibly applied is assumed, the process of manufacturing the load block, load test, and subsidence measurement is necessary for its implementation. Based on this, it is possible for the first time to determine the bottom mound based on the amount of subsidence, and a great amount of man-hours and costs are required.

  The present invention has been made in view of the above problems, and the purpose of the present invention is to grasp the compaction pressing force applied to the bottom mound at any time when compacting the bottom mound using a sand pile construction ship, It is possible to control the compaction pressing force as appropriate, to control the settlement of the rubble mound, and to always carry out construction management of a high-standard water bottom mound that is homogeneous and robust without relying solely on experience and intuition.

In order to solve the above problems, the method of compacting a bottom mound according to the present invention is to press a tamper attached to the bottom end of a hollow pipe for sand pile formation on a sand pile formation ship against a mound built on the bottom of the ground, A method of compacting the mound by vibrating the tamper with a vibro hammer installed at the head of the hollow tube, and measured values of each part obtained during the compacting operation and values grasped in advance Based on the above, during the compaction operation, the compaction pressing force of the mound is obtained at any time, and the compaction pressing force is appropriately controlled to compact the mound.
In order to solve the above-mentioned problems, a submerged mound compaction device according to the present invention includes a tamper mounted on a lower end of a hollow pipe for sand pile formation of a sand pile formation ship, and the hollow pipe head A vibro hammer installed in the electric motor, an electric motor for driving the vibro hammer, and a computing device for obtaining a compaction pressing force of the mound, wherein the computing device includes measured values of each part obtained during the compacting operation; Based on the value obtained in advance, during the compaction operation, the compaction pressing force of the mound is obtained at any time, and the compaction pressing force is appropriately controlled to compact the mound.

(Aspect of the Invention)
The following aspects of the present invention exemplify the configuration of the present invention, and will be described separately for easy understanding of various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or further while referring to the best mode for carrying out the invention. Those to which the above components are added can also be included in the technical scope of the present invention.
(1) Press the tamper attached to the bottom of the hollow pipe for sand pile construction on the sand pile construction ship against the mound built on the bottom of the water bottom, and vibrate the tamper with the vibro hammer installed on the hollow pipe head by, a method for performing compaction of the mounds, with the weight of the system driven by the vibro-hammer over the output of the electric motor for driving the vibro-hammer over, and a driving speed of the tamper, the A submerged mound compaction method characterized in that a mound compaction pressing force is obtained, and the compaction pressing force is appropriately controlled to perform compaction of the mound (claim 1).
The bottom mound compaction method described in this section is based on the weight of the system driven by the vibro hammer that can be grasped in advance, the output of the electric motor that drives the vibro hammer, and various conditions. possible grasp, with a tamper implantation rate, determined at any time compaction pressing force of the mound by the operation of the vibro-hammer over the Sunakui reclamation vessel, by controlling the compaction pressing force appropriately, applied to the mound fastening The pressing force is optimized over the entire bottom mound.

(2) A submerged mound compaction method for obtaining a compaction pressing force per unit area of the tamper when determining the compaction pressing force of the mound in the above (1) (claim 2) .
The water bottom mound compaction method described in this section is to obtain the compaction pressing force per unit area of the tamper compaction surface when calculating the compaction pressing force of the mound. Regardless of the method, the compaction pressing force applied to the bottom mound is optimized for each unit area, thereby optimizing the compaction pressing force over the entire bottom mound.

(3) A submerged mound compaction method for obtaining a compaction pushing force based on a size of a constituent member of the mound when obtaining the compaction pushing force of the mound in the above item (2) (claim 3) .
The submerged mound compaction method described in this section determines the mound compaction pressing force based on the size of the mound components that can be grasped in advance. Regardless of the component, the compaction pressing force applied to the bottom mound is optimized throughout the bottom mound.

(4) In the above (3), the mound compaction pressing force Ru is
Ru = 10.2 × Pw / (α · A · v + β) × 1 / Ta × γ (I)
Submerged mound compaction method determined based on (claim 4) .
The submerged mound compaction method described in this section is based on the formula (I). Obtain the mound compaction pressing force by the operation of the vibro hammer of the sand pile construction ship as needed, and control this compaction pressing force as appropriate. Thus, the compaction pressing force applied to the mound is optimized over the entire bottom mound.

(5) A tamper mounted on the lower end of the hollow pipe for sand pile formation of the sand pile building ship, a vibro hammer installed at the head of the hollow pipe, an electric motor for driving the vibro hammer, A submarine mound comprising: a weight of a system driven by a vibro hammer; an output of an electric motor that drives the vibro hammer; and an arithmetic unit that obtains a compaction pressing force of the mound using the tamper driving speed. Compaction device (Claim 5).
The submarine mound compaction device described in this section is based on the weight of the system driven by the vibro hammer that can be grasped in advance, the output of the electric motor that drives the vibro hammer, and various conditions. Using the tamper driving speed that can be grasped, the calculation device can obtain the compaction pressing force of the mound by the operation of the vibro hammer of the sand pile formation ship as needed. And this compaction pushing force is suitably controlled by an operator's judgment or automatic control, and the compaction pushing force given to a mound is optimized over the whole bottom mound.

(6) In the above item (5), the arithmetic unit includes a control logic for obtaining a compaction pushing force per unit area of the compaction surface of the tamper when obtaining the compaction pushing force of the mound. A submerged mound compaction device (Claim 6).
The bottom mound compaction device described in this section calculates the compaction pressing force per unit area of the tamper compaction surface when calculating the compaction pressing force of the mound by the arithmetic unit. Regardless of the construction state, the compaction pressing force applied to the bottom mound is optimized for each unit area, and thus the compaction pressing force is optimized over the entire bottom mound.

(7) In the above item (6), the arithmetic unit includes a control logic for obtaining a compaction pushing force based on a size of a constituent member of the mound when obtaining the compaction pushing force of the mound. A mound compaction device (Claim 7).
The submarine mound compaction device described in this section is to obtain the compaction pressing force based on the size of the mound component, which can be grasped in advance when calculating the compaction pressing force of the mound by the arithmetic unit. Regardless of the components of the mound, the compaction pressing force applied to the bottom mound is optimized over the entire bottom mound.

(8) In the above item (7), the arithmetic unit includes:
Ru = 10.2 × Pw / (α · A · v + β) × 1 / Ta × γ (I)
A submerged mound compaction device including a control logic for determining the compaction pressing force Ru of the mound based on the above (claim 8).
The submerged mound compaction method described in this section is based on the formula (I) when calculating the mound compaction pushing force by the arithmetic unit, and the mound compaction pushing force by the operation of the vibro hammer of the sand pile building ship Thus, the compaction pushing force applied to the mound is optimized over the entire bottom mound by appropriately controlling the compaction pushing force.

  Since the present invention is configured as described above, when compacting the bottom mound using a sand pile construction ship, it is possible to grasp the compaction pressing force applied to the bottom mound at any time and control the compaction pressing force as appropriate. It becomes. Therefore, it is possible to suppress the settlement of the rubble mound, and to perform construction management of a high-standard water bottom mound that is always homogeneous and robust without relying solely on experience and intuition.

It is a schematic diagram which shows the characteristic part of the compaction apparatus of the bottom mound which concerns on embodiment of this invention. It is a flowchart of the compaction operation | work by the compaction apparatus of the bottom mound which concerns on embodiment of this invention. It is explanatory drawing of the computing equation performed in the step which calculates | requires compaction pushing force of the flowchart of FIG. FIG. 2 illustrates the relationship between the tamper driving speed and the compacting pressing force obtained in the step of obtaining the compacting pressing force in the flowchart of FIG. 2, and FIG. The chart and (b) are the same graphs. It is a mimetic diagram showing a sand pile formation hollow pipe and a tamper attached to the lower end of a sand pile formation ship which constitutes a water bottom mound compaction device concerning an embodiment of the invention. It is explanatory drawing which shows generalizing the procedure which performs the compacting operation | work of the top end surface of a bottom bottom mound, moving the position of a tamper with the bottom bottom mound compaction apparatus which concerns on embodiment of this invention. (A) is a sectional view and a plan view of the bottom mound schematically illustrating the state of the bottom mound and the tamper at the time indicated by the circled numeral 1 in FIG. 6, and (b) is a circle in FIG. It is the same sectional drawing and top view at the time shown by the number 4 It is a schematic diagram which shows the mode of the compacting work of the water bottom mound using the conventional sand pile construction ship. It is a side view which shows the mode of the compacting operation | work of the water bottom mound using the conventional sand pile formation ship.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. Here, parts that are the same as or correspond to those in the prior art are assigned the same reference numerals, and detailed descriptions thereof are omitted.
The water-bottom mound compaction device according to the embodiment of the present invention performs compaction of the water-bottom mound M using the sand pile formation ship 10. As shown in FIG. 1 (see also FIG. 8 and FIG. 9), the sand pile building ship 10 has a hopper 18 and a vibro hammer 16 fixed to the head of the sand pile building hollow pipe 12. . Further, the vibro hammer 16 is suspended by the fishing line 22 wound and fed by the winch, so that the sand pile forming hollow pipe 12 can be raised and lowered along the vertically extending leader 20. And three sets of these hollow pipes 12 for sand pile formation and its peripheral equipment are provided in parallel at predetermined intervals.
The hopper 18 at the head of the sand pile building hollow pipe 12 is used for feeding components into the sand pile building hollow pipe 12 during sand pile building. In this case, it is also used when it is necessary to throw stones or the like on the bottom mound. In such a case, as in the case of sand pile construction, stones and the like put in the sand bin 24 (see FIG. 9) are passed through the belt conveyor 26 and a bucket (not shown) that moves up and down in the leader 20, and the hopper 18 It is thrown into.

Further, as shown in FIG. 5, tampers 14 (14A, 14B, 14C) are fixed to the lower ends of the respective sand pile forming hollow tubes 12 (12A, 12B, 12C). The tamper 14 has a rectangular box shape, and a cylindrical body 30 reinforced by a plurality of ribs 28 is erected at the center thereof. And the cylinder 30 and the lower end part of the hollow pipe 12 for sand pile formation are fixed so that attachment or detachment is possible using a volt | bolt etc. In addition, when stones or the like are additionally added at the time of compaction of the bottom mound, the one having the through hole of the cylindrical body 30 on the bottom surface (consolidation surface) of the tamper 14 is used. A stone or the like is discharged from the through hole through the hollow tube 12 and the cylindrical body 30.
In the embodiment of the present invention, as shown in FIG. 7, the sand pile building hollow pipes 12A, 12B, and 12C are provided at an interval of 5.4 m. Each of the tampers 14A, 14B, 14C has a square shape with a piece of 3 m.

In addition, a float weight 34 suspended from the rope 32 is provided on the sand pile building ship 10 so as to land on it, and a sensor such as a so-called cell thin transmitter provided in a winding device 36 for the rope 32. by 38, it is possible to grasp the Domo water value based on the feed amount of the rope 32. Further, the rope 40 is also connected to the sand pile forming hollow pipe 12, and the depth value is grasped based on the feeding amount of the rope 40 by a sensor 44 such as a serthin transmitter provided in the winding device 42 of the rope 40. be able to. Furthermore, the sensor 48 which detects the electric current value of the electric motor 46 which drives the vibro hammer 16 is provided, and the sensor 50 which measures a tide level value is also provided in the sand pile formation ship 10.

  Further, in the maneuvering room 52 of the sand pile building ship 10 is provided an arithmetic unit 54 capable of obtaining the compaction pressing force of the mound M. The arithmetic unit 54 includes an arithmetic processing unit 56 such as a personal computer. The arithmetic unit 54 receives detection signals obtained by the sensors 38, 44, 48, and 50 via the A / D conversion unit 58. In consideration of input and timer count, calculation, display, recording, abnormality alarm, etc. are output. Then, on the display unit 60 such as a monitor, the compacting pressing force Ru of the bottom mound M obtained by a method described in detail later is displayed together with each data such as the initial set value, parameters, and time. The display area indicated by reference numeral 62 of the display unit 60 visually represents the depth of the tamper 14.

  And the compaction operation | work of the bottom mound M using the compaction apparatus of the bottom mound which concerns on embodiment of this invention is performed in the procedure illustrated by FIG. 6, FIG. FIG. 6 shows a general procedure for compacting the bottom mound M while moving the position of the tamper 14, and the top end surface of the bottom mound M is divided into a plurality of troughs for convenience of explanation. It is shown. And the numbers 1-12 with a circle in each cage | basket | mean that the part of the same number is compacted simultaneously by three sets of tamper 14A, 14B, 14C.

Specifically, the portion indicated by the circled number 1 (A row: 101 column, 103 column, 105 column) is first compacted, and then the sand pile building vessel 10 is moved and indicated by the circled number 2 The portion (A row: 102 columns, 104 columns, 106 columns) is compacted, and then the portion indicated by the circled number 3 (B rows: 102 columns, 104 columns, 106 columns), the circled number 4 The shown portion (B row: 101 column, 103 column, 105 column),... Is performed over the entire bottom mound.
In addition, in this Embodiment, from the relationship between the space | interval of each hollow pipe 12A, 12B, 12C for sand pile formation, and the length of one piece of each tamper 14A, 14B, 14C, Fig.7 (a), (b) As shown in FIG. 2, the compacting operation is performed so that adjacent ridges partially overlap each other.

  At this time, in the arithmetic unit 54, the weight of the system driven by the vibro hammer, that is, the sand pile forming hollow pipe 12 and the tamper 14 (including the hopper 18 as necessary), the electric motor 46 for driving the vibro hammer 16 is obtained. In consideration of the output and the tamper driving speed, the compaction pressing force Ru of the bottom mound M is obtained, and the compaction pressing force is appropriately controlled to compact the mound. The specific procedure will be described below with reference to FIGS. 1 to 3 and FIG.

(S0) position of the tamper 14, working position of the compaction work of the water bottom mound M (initially the position illustrated by circled numeral 1 in FIG. 6) to move the Sunakui reclamation vessel 10 so that, anchor, etc. To fix the position of the sand pile building ship 10. Then, necessary initial setting values are input to the arithmetic unit 54.
(S10) The tamper descending depth measurement at the time of performing the compacting operation is obtained from the feeding amount of the rope 40 in consideration of the measurement results of the sensors 38, 44 and 50.
(S20) The vibro hammer 16 is operated.
(S30) Based on the tamper descending depth measurement obtained in S10, the tamper 14 is lowered so as to come into contact with the top end surface of the bottom mound M, and the rolling is leveled.

(S40) in the arithmetic unit 54, from the sensor 38,44,48,50, vibro-hammer over the current value (current value of the electric motor 46), the depth value, Domo water value, to obtain the tide level value. In addition, the timer count is acquired.
(S50) In the arithmetic unit 54, the vibro hammer current value is acquired from the sensor 48, and the driving speed v is obtained. The driving speed v means the moving distance from the point where the tamper 14 contacts the top end surface of the bottom mound M to the specified depth and the time required for it, and can be obtained by dividing the moving distance by time.

(S60) In the arithmetic unit 54, the compaction pressing force Ru of the bottom mound M is obtained. Specifically, in the arithmetic processing unit 56 of the arithmetic unit 54, the mathematical formula Ru = 10.2 × Pw / (α · A · v + β) × 1 / Ta × γ (I) shown in FIG.
Thus, the compaction pressing force Ru of the bottom mound M is obtained by performing the calculation along the line.
This formula (I) is based on the formula that calculates the bearing capacity of piles recommended by the Vibro Hammer Method Technical Committee for the purpose of managing the bearing capacity of foundation piles in harbor structures. As a result of the study, it is possible to accurately obtain the compacting pressing force Ru of the bottom mound M. The compaction pushing force Ru is obtained from the balance of energy. In summary, the time unit for releasing energy is taken into account according to the characteristics of the vibro hammer, and the added work amount and the kinetic energy of the tamper (the driving speed). ) To obtain Ru.
Note that the pressing force Ru of the bottom mound M is obtained for each of the tampers 14A, 14B, and 14C.

Incidentally, in formula (I), 1 / a of that multiplied by Ta, a piece has been found using in the embodiments of the present invention is a 3m of the tamper 14, the area of the compacted surface Ta = 3 (m) × This is because a compacting pressing force Ru per unit area is obtained by considering 3 (m) = 9 (m ² ). Further, in order to obtain the compacting pressing force based on the size of the stone that is a constituent member of the bottom mound M, the coefficient γ is multiplied. The size of the stone varies depending on, for example, the place where the stone material is procured at the construction site, and the size varies from 50 kg or less to 300 kg or more per piece. In the formula (I), as shown in FIG. 3, by setting the γ value in the range of 0.27 to 0.35, it is possible to accurately reflect the difference in stone size on the compacting pressing force Ru. It becomes. The values of 1 / Ta and γ are appropriately taken into consideration as necessary.
(I) range of the current value I _A at the applicable Uchidome in equation shall be within 150% of the rated current value of the electric motor 46. The term “at the time of hitting” here means that it is greater than the target compaction pressing force and satisfies the specified depth. The penetration speed coefficient α based on the vibration frequency means the relationship between the performance of the vibro hammer and the speed due to the tip resistance. It is obtained by dividing the vibration frequency of the vibro hammer by the frequency of the generator to be used and converted into a coefficient. It is. β is a coefficient based on the reduction rate of the resistance due to vibration of the vibro hammer. For example, when the constituent member of the bottom mound M is calcite, β = 0.1 as shown in FIG.

(S70) In the computing device 54, the compaction pressing force Ru of the bottom mound M is compared with a preset target compaction pressing force. Since the compaction pressing force Ru of the bottom mound M obtained in S60 is displayed on the display unit 60 as shown in FIG. 1, when the compaction pressing force Ru falls below the target value, the operator's Necessary setting changes are made by operation, or setting changes are preliminarily incorporated in the arithmetic processing unit 56 of the arithmetic unit 54, so that necessary setting changes are automatically made, and S30 to S70 are repeated.
(S80) In S70, when it is determined that the compacting pressing force Ru is equal to or greater than the target value, whether or not the position (equalization depth) of the tamper 14 at that time is a specified depth is determined in the arithmetic unit 54 This is determined from the depth value of the sensor 44. And since the depth value of the tamper 14 is displayed on the display unit 60 as shown in FIG. 1, if the depth value is not the specified depth, the setting of each unit is changed by the operator's operation, or The setting change logic is incorporated in advance in the arithmetic processing unit 56 of the arithmetic unit 54, so that the setting of each part is automatically changed, and S30 to S80 are repeated.

(S90) If it is determined in S80 that the position (equalization depth) of the tamper 14 is at the specified depth, the value of the compacting pressing force Ru at that time is sent to the arithmetic processing unit 56 of the arithmetic unit 54. Record.
(S100) The fishing line 22 is rolled up to raise the sand pile forming hollow tube 12, and the tamper is wound up.
(S110) The vibro hammer 16 is stopped.
Thereafter, the compaction position of the bottom mound M is changed according to the procedure illustrated in FIGS. 6 and 7, and S0 to S110 are repeated to perform the compaction operation over the entire bottom mound M.

  FIG. 4 exemplifies the compaction pressing force Ru of the bottom mound M obtained in S60 of FIG. 2 in relation to the tamper driving speed v. Specifically, a 300 kw specification (eccentric moment K = 3920 N · m) is used for the vibro hammer 16, and the size of the stone that is a component of the bottom mound M is 99 kg / piece or less (coefficient γ = 0.35). Some cases are shown for different equal depths. As a tendency, it can be understood that the compacting pressing force Ru increases as the tamper driving speed v decreases, and the compacting pressing force Ru increases as the smoothing depth increases regardless of the leveling depth. In the above-described compaction operation of the bottom mound M, the compaction pressing force Ru thus grasped is appropriately controlled to advance the compaction of the bottom mound M.

Now, according to the embodiment of the present invention configured as described above, the following operational effects can be obtained.
That is, the compaction device for the bottom mound according to the embodiment of the invention measures the weight of the system (sand pile forming hollow pipe 12 and tamper 14) driven by the vibro hammer 16 that can be grasped in advance and appropriately measured. In consideration of the possible output (current value) of the electric motor 46 that drives the vibro hammer 16 and the tapping speed v of the tamper 14 that can be grasped based on various conditions, the arithmetic unit 54 uses the sand pile formation ship 10. The compaction pressing force Ru of the bottom mound M due to the operation of the vibro hammer 16 is determined at any time (S60). And this compaction pushing force Ru is appropriately controlled by the operator's judgment or by automatic control, so that the compaction pushing force Ru applied to the bottom mound M is optimized over the whole bottom mound M. Is.

In the embodiment of the present invention, when the compaction pressing force Ru of the bottom mound M is obtained by the arithmetic unit 54, the area Ta of the tamper compaction surface is taken into consideration, so that the construction state of the bottom mound M is determined. Regardless of this, the compaction pressing force Ru applied to the bottom mound M is optimized for each unit area, so that the compaction pressing force Ru is optimized over the entire bottom mound M.
Furthermore, when the compaction pressing force Ru of the bottom mound M is obtained by the arithmetic unit 54, the size of the component of the bottom mound M that can be grasped in advance is taken into consideration (coefficient γ). Regardless of the component, the compaction pressing force Ru applied to the bottom mound M is optimized over the entire bottom mound M.

  10: Sand pile construction ship, 12: Hollow pipe for sand pile construction, 14: Tamper, 16: Vibro hammer, 38, 44, 48, 50: Sensor, 46: Electric motor, 54: Arithmetic unit, 56: Arithmetic processing Equipment, M: Bottom mound, Ru: Compaction pressing force

Claims (8)

Press the tamper attached to the lower end of the hollow pipe for sand pile construction of the sand pile construction ship against the mound built on the bottom of the water, and vibrate the tamper with the vibro hammer installed on the head of the hollow pipe, A method of compacting the mound,
And weight system driven by said vibro-hammer over the output of the electric motor for driving the vibro-hammer over the use and tamper implantation rate, determine the compaction pressing force of the mounds, a該締consolidate pushing force A submerged mound compaction method, wherein the mound compaction is performed under appropriate control. The submerged mound compaction method according to claim 1, wherein the compaction pressing force per unit area of the compaction surface of the tamper is determined when the compaction pressing force of the mound is determined. 3. The submerged mound compaction method according to claim 2, wherein when the mound compaction pushing force is obtained, the compaction pushing force based on the size of the component of the mound is obtained . The mound compaction pushing force Ru is
Ru = 10.2 × Pw / (α · A · v + β) × 1 / Ta × γ
Pw: Actual motor output when tampering is stopped
_{Pw = 1.3 × I A × E} × 10 -3
I _A : Maximum current value at stopping
E: Minimum voltage at stop
α: Penetration speed coefficient based on vibration frequency of vibro hammer
f: Vibration frequency
A: Calculated amplitude
A = (K / g) / (Wν + Wp) × 10 ²
K: Eccentric moment
g: Gravity acceleration
Wν: Vibro hammer vibration weight
Wp: Weight minus the buoyancy of the hollow tube driven by the vibro hammer
v: Tamper driving speed
β: Coefficient based on the reduction rate of resistance due to vibration
Ta: Tamper compaction area
The submerged mound compaction method according to claim 4, wherein γ is determined based on a coefficient based on the size of the component of the mound. A tamper mounted on the lower end of a hollow pipe for sand pile formation of a sand pile formation ship, a vibro hammer installed at the hollow pipe head, an electric motor that drives the vibro hammer,
And an arithmetic unit for determining a compacting pressing force of the mound using a weight of a system driven by the vibro hammer, an output of an electric motor driving the vibro hammer, and a driving speed of the tamper. A compacting device for the bottom mound. 6. The arithmetic unit includes a control logic for determining a compaction pressing force per unit area of the compaction surface of the tamper when determining the compaction pressing force of the mound. Underwater mound compaction device. 7. The water bottom according to claim 6, wherein the arithmetic unit includes a control logic for obtaining a compaction pressing force based on a size of a constituent member of the mound when the compaction pressing force of the mound is obtained. Mound compaction device. The arithmetic unit includes
Ru = 10.2 × Pw / (α · A · v + β) × 1 / Ta × γ
Pw: Actual motor output when tampering is stopped
_{Pw = 1.3 × I A × E} × 10 -3
I _A : Maximum current value at stopping
E: Minimum voltage at stop
α: Penetration speed coefficient based on vibration frequency of vibro hammer
f: Vibration frequency
A: Calculated amplitude
A = (K / g) / (Wν + Wp) × 10 ²
K: Eccentric moment
g: Gravity acceleration
Wν: Vibro hammer vibration weight
Wp: Weight minus the buoyancy of the hollow tube driven by the vibro hammer
v: Tamper driving speed
β: Coefficient based on the reduction rate of resistance due to vibration
Ta: Tamper compaction area
8. The underwater mound compacting device according to claim 7, further comprising: control logic for obtaining a compacting pressing force Ru of the mound based on a coefficient based on a size of the component member of the mound.

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