Ground improvement system and ground improvement method

Abstract

To provide a new ground improvement system and ground improvement method which are different from a conventional method.SOLUTION: A ground improvement system X has ground improvement means X1 for improving a ground G under a water surface W, and a total station 11 installed in an adjacent ground 90, wherein the ground improvement means X1 has a barge 12, an improver 13 provided with an excavation shaft 13A and a control device 14 of an improvement machine, and the total station 11 measures a height of the ground improvement means X1 and corrects depth information F on the basis of the measurement value. A ground improvement method includes installing a prism 15 on the barge 12, measures an initial height A of the prism 15, an altitude B of the total station 11 and a height difference C between the total station 11 and the prism 15, corrects a measurement depth E of the excavation shaft 13A on the basis of the measurement value, and sets the depth after correction as depth information F.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a ground improvement system and a ground improvement method for improving ground below water level. [Background technology]

[0002] When improving underwater ground such as the seabed using a ground improvement machine equipped with a drilling shaft mounted (installed) on a barge, if the tide level changes during construction, the depth information of the drilling shaft will be inaccurate. In ground improvement, it is extremely important to accurately grasp the depth of the drilling shaft, because cement and other solidifying materials are injected into the ground from the drilling shaft according to the depth information, and the degree of ground mixing by the drilling shaft (rotation speed, etc.) is changed.

[0003] Therefore, a method has been proposed in which the depth information of the excavation axis is corrected by inputting the change in the water level at the construction site where the barge is floating (for example, see Patent Document 1). However, this method does not take into account, for example, the sinking of the barge (change in the barge's draft), and is therefore less accurate.

[0004] Also, for example, a method has been proposed in which a mobile GPS is installed, the relative positions of the mobile GPS and the excavation axis are identified, and the coordinates of the excavation axis are measured (see, for example, Patent Document 2). However, the use of a mobile GPS is vulnerable to communication failures and is cumbersome. Furthermore, there is a demand for methods of inputting water level changes and methods other than those using a mobile GPS (diversification of means) as described above. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4405996 [Patent Document 2] Patent No. 3571585 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is to provide a new ground improvement system and a new ground improvement method that differ from conventional methods. [Means for solving the problem]

[0007] The means for solving the above problems are as follows. (Means described in claim 1) A ground improvement means for improving the ground below the water surface and a total station installed on the ground adjacent to the water surface, The ground improvement means includes a barge floating on the water surface, an improvement machine having a drilling shaft, and a Measured by a depth measuring device that measures depth and a control device for controlling the improved machine in accordance with depth information, the improved machine and the control device being installed on the barge; The total station measures the ground improvement means. From the water surface Measure the height and this measurement is added to the depth information to obtain the corrected depth information. The structure is as follows: A ground improvement system characterized by:

[0008] (Means described in claim 2) A prism is installed on the barge, and the From the water surface The height is measured by the total station, and this measurement value is added to the depth information to obtain the corrected depth information. The structure is as follows: The ground improvement system according to claim 1.

[0009] (Means described in claim 3) An improved machine equipped with a drilling shaft capable of measuring depth, and According to the above measurement and a control device that controls the improvement machine according to depth information, and the improvement machine and the control device use ground improvement means installed on a barge to insert the excavation shaft into the ground below the water surface, A total station is installed on the ground adjacent to the water surface, and a prism that pairs with the total station is installed on the barge; The prism From the water surfaceMeasure the height and the elevation of the total station; The total station is used to measure the height difference between the total station and the prism, and the height difference and the height of the prism are calculated. From the water surface height, the elevation of the total station, Add the above depth information to the corrected Depth information: A ground improvement method comprising the steps of: Effect of the Invention

[0010] According to the present invention, a new ground improvement system and a new ground improvement method are provided which are different from conventional methods. [Brief description of the drawings]

[0011] [Figure 1] 1 is an example of the device configuration of a ground improvement system according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Next, an embodiment of the present invention will be described. Note that the embodiment is an example of the present invention. The scope of the present invention is not limited to the scope of the embodiment.

[0013] (Ground Improvement System) As shown in Fig. 1, the ground improvement system X of this embodiment has a ground improvement means X1 that improves ground G below the water surface W, and a total station 11 installed on the ground adjacent to the water surface W (bank 90 in the illustrated example). The ground improvement means X1 also has a barge 12 floating on the water surface W, an improvement machine 13 equipped with an excavation shaft 13A, and a control device 14 that controls the improvement machine 13 according to depth information of the excavation shaft 13A, etc. Furthermore, the improvement machine 13 and the control device 14 are installed on the barge 12.

[0014] In this embodiment, the height of the ground improvement means X1 is measured by the total station 11, and the depth information of the excavation axis 13A is corrected based on this measurement value. Therefore, this is a new system that differs from the conventional system described above. In particular, unlike the method of inputting the change in tide level (water level) described above, the sinking of the barge 12 and the like are also taken into consideration, improving accuracy. In addition, since it does not use a GPS system but uses the total station 11 that is used in the field of general surveying, it is extremely simple.

[0015] In this embodiment, the water surface W is assumed to be, for example, the surface of the sea, a river, a lake, etc. However, it is not intended to limit the water surface W to these. This embodiment is applicable when the ground to be improved is below some water surface, and a barge is floated on the water surface and construction is carried out on the barge.

[0016] The barge 12 is sometimes called, for example, a work boat or the like. The barge 12 is appropriately moored at its four corners with stakes (anchors) or ropes to restrict its movement in the horizontal direction (direction along the water surface W). On the other hand, the barge 12 moves in the vertical direction (direction intersecting the water surface W) due to changes in the water level, etc.

[0017] However, it is preferable to minimize vertical movement as well, and it is particularly preferable to load equipment and materials whose weight changes, such as the solidification material itself and its plant equipment, onto a separate work boat adjacent to the barge 12.

[0018] The improvement machine 13 is equipped with an excavation shaft 13A for excavating the ground G. The excavation shaft 13A may be a single shaft or a multi-shaft shaft having two or more shafts. Depending on the depth to which the ground G is excavated, a single excavation shaft may be formed by connecting multiple single pipes.

[0019] The drilling shaft 13A is usually supported vertically by a support such as a leader, etc. The drilling shaft 13A can be moved up and down and rotated around its axis by a driving device equipped with a motor, etc.

[0020] The excavation shaft 13A in this embodiment is provided with a depth measuring means (depth gauge) for measuring the depth of the excavation shaft (usually the tip of the excavation shaft). This depth measuring means measures the depth of the excavation shaft, but as mentioned above, there is a possibility that an error will occur in this measured depth due to the change in the water level of the water surface W.

[0021] The drilling shaft 13A is appropriately provided with a drilling bit, a mixing blade, a solidification material, a discharge port for water or the like, an air outlet, and the like.

[0022] The improvement machine 13 is appropriately equipped with a discharge meter for solidification material, etc., a depth meter for the excavation shaft 13A (described above), a rotation meter, etc. The measurement information measured by these various instruments is sent to the control device 14 by wire or wirelessly.

[0023] The control device 14 may be provided with a display device, a printer, etc. for displaying the above-mentioned measurement information, if necessary.

[0024] The control device 14 determines the vertical movement and rotation of the excavation shaft 13A based on the above measurement information, and controls the excavation shaft 13A based on this determined information. This control may be corrected at the discretion of the operator if necessary. However, the above control is corrected according to the displacement (change) of the height of the barge 12, as will be explained below.

[0025] That is, first, the barge 12 in this embodiment is equipped with a prism 15. This prism is a device that pairs with the total station 11, and can be omitted if possible (non-prism type). The height of the prism 15 is measured by the total station 11. Note that the height of the prism 15 changes due to changes in the water level as well as changes in the draft of the barge 12.

[0026] The prism 15 can be mounted on the improved machine 13, for example, but is preferably mounted directly on the barge 12 as in this embodiment. If it is mounted on the improved machine 13, it will pick up the vibrations of the improved machine 13. On the other hand, the mounting position of the prism 15 in the planar direction (direction along the water surface W) is not particularly limited, and it can be suitably installed in a location where there are no obstacles between it and the total station 11.

[0027] The total station 11 is installed on the ground adjacent to the water surface W, in the illustrated example, on the revetment 90. One total station 11 is sufficient, but two or more total stations may be used if necessary. Also, another total station may be installed to obtain position information of the barge 12 (position information in the direction along the water surface W). In this case, two or more total stations are usually installed.

[0028] The measurement values ​​measured by the total station 11 are processed by the repeater 16 and transmitted to the control device 14. Transmission of the measurement values ​​from the repeater 16 to the control device 14 can be performed by wire, but in the illustrated example, a form by Wi-Fi means using the access points 14A and 16A, that is, a wireless form, is shown. When using Wi-Fi, the distance between the access points 14A and 16A is, for example, 200 m or less (0 to 200 m). Of course, if other wireless means is used, the transmission (communication) distance can be extended to, for example, about 300 m.

[0029] The control means 14, which has received the height (measurement value) of the barge 12, corrects the measured depth of the excavation shaft 13A, and controls the excavation shaft 13A based on this corrected depth information.

[0030] (Soil improvement method) Next, a ground improvement method using the above-mentioned ground improvement system X will be described. In the ground improvement method of this embodiment, first, the improvement machine 13, control device 14, prism 15, etc. are loaded onto the barge 12, and then the barge 12 is positioned above the ground G to be improved.

[0031] As described above, it is usually preferable to moor the barge 12 at its four corners with stakes (anchors) or ropes to prevent it from moving in a planar direction (the direction along the water surface W).

[0032] Next, when the preparation for construction of the improvement machine 13, the control device 14, the prism 15, etc. is completed, the tip of the drilling shaft 13A is aligned with the water surface W. In addition, the initial height A from the water surface W to the prism 15 is measured and transmitted to or input into the control device 14.

[0033] On the other hand, a reference plane L, such as the Tokyo Bay mean sea level (TP) for Tokyo Bay or the Arakawa River construction datum (AP) for the Arakawa River, is set to 0 m, and the height (altitude) B from this reference plane L to the total station 11 is measured. This measurement value is also transmitted to or input into the control device 14.

[0034] Next, the total station 11 is used to measure the height difference C of the prism 15 relative to the total station 11, and the height difference C is transmitted to the control device 14. In this embodiment, this transmission is performed using Wi-Fi means. As described above, this transmission may be performed using other wireless means or wired means.

[0035] On the other hand, the control device 14 calculates a depth correction value D based on the above information (initial height A, altitude B, and elevation difference C). For example, if the initial height A of the prism 15 is 1.5 m, the altitude B of the total station 11 is 4.0 m, and the elevation difference C of the prism 15 relative to the total station 11 is -1.0 m, Depth correction value D = -A (initial height) + B (altitude) + C (height difference) = -1.5 + 4.0 - 1.0 = 1.5m It becomes.

[0036] Then, the measured depth E of the excavation shaft 13A is corrected based on this depth correction value D. Specifically, for example, if the measured depth E is -5.0 m, Depth information F = D (depth correction value) + E (measured depth) = 1.5 - 5.0 = -3.5m It becomes.

[0037] Thereafter, the height difference C of the prism 15 is measured in real time or at an appropriate stage, and this measurement value is transmitted to the control device 14, which calculates the depth correction value D and corrects the measured depth (calculates the depth information F).

[0038] To briefly explain the subsequent steps, for example, first, the excavation shaft 13A is moved downward, and when it reaches the bottom of the water, the excavation shaft 13A is rotated or a solidification material is discharged as appropriate to improve the ground G. Here, such control of the excavation shaft 13A is performed based on the depth information of the excavation shaft 13A, but as described above, the depth information is affected by changes in the water surface W and the sinking of the barge 12. Therefore, in this embodiment, at appropriate stages, such as when the excavation shaft 13A is thought to have reached the bottom of the water (ground G) or when it is thought to have reached the bottom end of the improved ground G, the elevation difference C of the prism 15 is measured by the total station 11, preferably in real time, and transmitted to the control device 14.

[0039] In the control device 14, the measured depth E of the excavation axis 13A is corrected using the elevation difference C from the total station 11. The depth calculated by this correction becomes the depth information F. This depth information F is extremely accurate, and therefore, it becomes possible to carry out improvement of the ground G based on accurate information.

[0040] In the above, a form in which correction is performed using the height difference C of the prism 15 has been shown, but the correction is similar when it is performed using the change (displacement) in the height difference C. Furthermore, when the prism 15 is not used, the height of the barge 12 can be measured and the same operation can be performed. Therefore, the prism 15 is a target for the total station 11, and can be said to be a member that contributes to improving the measurement accuracy.

[0041] (others) In the ground improvement system and the ground improvement method of this embodiment, the method of ground improvement itself is not particularly limited. For example, it can be applied to a form in which the solidification material is discharged when the drilling shaft 13A is inserted into the ground G, a form in which the solidification material is discharged when the drilling shaft 13A is pulled out from the ground G, or a form in which the solidification material is discharged during both insertion and withdrawal. In addition to discharging the solidification material from the drilling shaft 13A, water can be discharged, air can be sprayed, etc.

[0042] Furthermore, examples of the control information based on the depth information F include the rotation speed and elevation speed of the drilling shaft 13A, the timing of solidification material discharge, the discharge amount, etc. These pieces of information can be acquired based on, for example, a rotation speed meter and a discharge amount meter attached to the drilling shaft 13A. [Industrial Applicability]

[0043] INDUSTRIAL APPLICABILITY The present invention can be used as a ground improvement system and a ground improvement method for improving ground below water level. [Explanation of symbols]

[0044] 11. Total Station 12 barge 13 Improved machine 13A Drilling shaft 14 Control device 14A Access Point 15 Prism 16 Repeater 16A Access Point 90 Seawall A Initial height B Altitude C Height difference D Depth correction value E Measurement depth F Depth information G. Ground L reference plane X Ground Improvement System X1 Ground improvement measures W water surface

Claims

1. A ground improvement means for improving the ground below the water surface and a total station installed on the ground adjacent to the water surface, The ground improvement means includes a barge floating on the water surface, an improvement machine equipped with an excavation shaft, and a control device that controls the improvement machine according to depth information measured by a depth measuring device that measures the depth of the excavation shaft, and the improvement machine and the control device are installed on the barge, The total station measures the height of the ground improvement means from the water surface, and the measured value is added to the depth information to obtain corrected depth information. A ground improvement system characterized by:

2. A prism is installed on the barge, and the height of the prism from the water surface is measured by the total station, and the measured value is added to the depth information to obtain corrected depth information. The ground improvement system according to claim 1 .

3. The method includes an improvement machine having an excavation shaft capable of measuring depth, and a control device that controls the improvement machine in accordance with depth information obtained by the measurement of the excavation shaft, and the improvement machine and the control device use ground improvement means installed on a barge to insert the excavation shaft into the ground below the water surface, A total station is installed on the ground adjacent to the water surface, and a prism that pairs with the total station is installed on the barge; measuring the height of the prism from the water surface and measuring the altitude of the total station; Using the total station, a height difference between the total station and the prism is measured, and the height difference, the height of the prism from the water surface, and the altitude of the total station are added to the depth information to obtain corrected depth information. A ground improvement method comprising the steps of:

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