Pile design program, pile design device, and pile design method

Abstract

To provide a pile design program capable of improving the construction accuracy of a new prefabricated pile when constructing a new prefabricated pile in the vicinity of an existing pile removal backfilling area formed by backfilling an excavated hole after removing an existing pile.SOLUTION: A pile design program is configured to calculate an overlap rate L between an existing pile removal backfilling part 14 formed by backfilling a drilled part 12 after removing an existing pile 10 and a new pile shaft drilled part 30 formed in the ground G when a new prefabricated pile 20 is newly installed in a planned position, and determine whether the calculated overlap rate L is within the tolerance.SELECTED DRAWING: Figure 13

Description

Technical Field

[0001] The present invention relates to a pile design program, a pile design device, and a pile design method.

Background Art

[0002] There is a ground improvement method for backfilling the bored hole after removing an existing pile while improving the ground (see, for example, Patent Documents 1 and 2).

[0003] In addition, there is a construction method of driving cast-in-place concrete piles into the backfilled portion where the bored hole after removing an existing pile is backfilled (see, for example, Patent Document 3).

[0004] Furthermore, there are documents on constructing a new pile in the backfilled portion where the bored hole after removing an existing pile is backfilled (see Non-Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0006]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] By the way, it is conceivable to install a prefabricated pile (hereinafter referred to as "newly installed prefabricated pile") in a backfill area (hereinafter referred to as "existing pile removal and backfill section") that fills the drilled hole for removing the existing pile.

[0008] In the construction of a newly installed prefabricated pile, first, a drilled hole (hereinafter referred to as "newly installed pile shaft drilled hole") is created in the ground, and the newly installed prefabricated pile is dropped into the created newly installed pile shaft drilled hole in a state where a ground improvement liquid and a pile perimeter fixing liquid are injected.

[0009] Here, if an existing pile removal and backfill section exists in the construction area of the newly installed pile shaft drilled hole, the newly installed pile shaft drilled hole may bend due to the strength difference between the existing pile removal and backfill section and the original ground, etc., and the construction accuracy of the newly installed prefabricated pile may decrease.

[0010] In consideration of the above facts, the present invention aims to improve the construction accuracy of a newly installed prefabricated pile when constructing the newly installed prefabricated pile near the existing pile removal and backfill section formed by filling the drilled hole after removing the existing pile.

Means for Solving the Problems

[0011] The pile design program according to claim 1 calculates the lap rate between the existing pile removal and backfill section formed by filling the drilled hole after removing the existing pile and the newly installed pile shaft drilled hole formed in the ground when installing a newly installed prefabricated pile at the planned position, and determines whether the calculated lap rate is an allowable value, and causes a computer to execute the process.

[0012] According to the pile design program according to claim 1, when the lap rate between the existing pile removal and backfill section formed by filling the drilled hole after removing the existing pile and the newly installed pile shaft drilled hole formed in the ground when installing a newly installed prefabricated pile at the planned position is outside the allowable value, the eccentricity of the newly installed pile shaft drilled hole may increase. As a result, the construction accuracy of the newly installed prefabricated pile may decrease.

[0013] In contrast, in the present invention, the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft is calculated, and it is determined whether the calculated lap rate is within the allowable value. Thereby, it is possible to easily grasp whether the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft is within the allowable value. Further, when the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft is outside the allowable value, by taking countermeasures, the construction accuracy of the new precast pile can be improved.

[0014] The pile design program according to claim 2 is the pile design program according to claim 1, wherein when the lap rate is outside the allowable value, information on whether it is possible to change the existing pile removal and backfilling diameter of the existing pile removal and backfilling section is obtained, and when the information on whether it is possible to change the existing pile removal and backfilling diameter is changeable, the computer is caused to execute a process of calculating the existing pile removal and backfilling diameter at which the lap rate becomes the allowable value.

[0015] According to the pile design program according to claim 2, when the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft is outside the allowable value, information on whether it is possible to change the existing pile removal and backfilling diameter of the existing pile removal and backfilling section is obtained. Then, when the information on whether it is possible to change the existing pile removal and backfilling diameter is changeable, the existing pile removal and backfilling diameter at which the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft becomes the allowable value is calculated.

[0016] Thereby, the lap rate between the existing pile removal and backfilling section and the bored section of the new pile shaft can be easily made to be within the allowable value. Therefore, the construction accuracy of the new precast pile can be improved.

[0017] The pile design program according to claim 3 is the pile design program according to claim 1, wherein when the lap rate is outside the allowable value, information on whether it is possible to change the planned position of the new precast pile is obtained, and when the information on whether it is possible to change the planned position of the new precast pile is changeable, the computer is caused to execute a process of calculating the planned position of the new precast pile at which the lap rate becomes the allowable value.

[0018] According to the pile design program according to claim 3, when the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is outside the allowable value, information on whether the planned position of the new precast pile can be changed is obtained. Then, when the information on whether the planned position of the new precast pile can be changed indicates that it can be changed, the planned position of the new precast pile at which the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part becomes the allowable value is calculated.

[0019] Thereby, the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part can be easily made to be the allowable value. Therefore, the construction accuracy of the new precast pile can be improved.

[0020] The pile design program according to claim 4 is the pile design program according to claim 1, and when the lap rate is outside the allowable value, information on whether the diameter of the new pile shaft part drilling hole of the new pile shaft part drilling part can be changed is obtained. When the information on whether the diameter of the new pile shaft part drilling hole can be changed indicates that it can be changed, the computer is made to execute a process of calculating the diameter of the new pile shaft part drilling hole at which the lap rate becomes the allowable value.

[0021] According to the pile design program according to claim 4, when the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is outside the allowable value, information on whether the diameter of the new pile shaft part drilling hole of the new pile shaft part drilling part can be changed is obtained. Then, when the information on whether the diameter of the new pile shaft part drilling hole can be changed indicates that it can be changed, the diameter of the new pile shaft part drilling hole at which the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part becomes the allowable value is calculated.

[0022] Thereby, the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part can be easily made to be the allowable value. Therefore, the construction accuracy of the new precast pile can be improved.

[0023] The pile design device according to claim 5 includes a control unit that executes a process of calculating the lap rate between the existing pile removal and backfilling part formed by backfilling the drilled part after removing the existing pile and the new pile shaft part drilling part formed in the ground when installing a new precast pile at the planned position, and determining whether the calculated lap rate is the allowable value.

[0024] According to the pile design device according to claim 5, the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is calculated, and it is determined whether the calculated lap rate is an allowable value. Thereby, it is possible to easily grasp whether the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is an allowable value. Further, by taking measures when the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is outside the allowable value, the construction accuracy of the newly installed precast pile can be improved.

[0025] The pile design method according to claim 6 is a process in which a computer calculates the lap rate between an existing pile removal and backfilling part formed by backfilling the drilled part after removing an existing pile and a new pile shaft part drilling part formed in the ground when installing a newly installed precast pile at a planned position, and determines whether the calculated lap rate is an allowable value.

[0026] According to the pile design method according to claim 6, the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is calculated, and it is determined whether the calculated lap rate is an allowable value. Thereby, it is possible to easily grasp whether the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is an allowable value. Further, by taking measures when the lap rate between the existing pile removal and backfilling part and the new pile shaft part drilling part is outside the allowable value, the construction accuracy of the newly installed precast pile can be improved.

Advantages of the Invention

[0027] As described above, according to the present invention, when constructing a newly installed precast pile near the existing pile removal and backfilling part formed by backfilling the drilled part after removing an existing pile, the construction accuracy of the newly installed precast pile can be improved.

Brief Description of the Drawings

[0028]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, an embodiment will be described with reference to the drawings.

[0030] As shown in FIG. 1, the pile design device 50 according to the present embodiment is, for example, a design support device that supports the design of a newly installed precast pile 20 when there is an existing pile removal and backfilling portion 14 formed by backfilling a drilling portion 12 for removing the existing pile 10 in the construction area of the drilling portion 30 of the newly installed precast pile 20.

[0031] (Existing pile removal and backfilling portion) As shown in FIGS. 1 and 2, the existing pile removal and backfilling portion 14 is an area where the drilling portion 12 for removing the existing pile 10 is backfilled.

[0032] Note that the existing pile 10 may be a steel pipe pile or a concrete pile. Further, the existing pile 10 may be a precast pile or a cast-in-place pile.

[0033] As a method for removing the existing pile 10, that is, a construction method for the existing pile removal and backfilling portion 14, for example, as in the construction method disclosed in Patent Document 2 (hereinafter referred to as the "improved wheel throwing method"), first, a casing is driven around the existing pile 10 to form the drilling portion 12, and the existing pile 10 inside the casing is pulled out by a heavy machine. Next, an auger is inserted into the casing, and the tip of the auger is expanded below the lower end of the casing. Then, while pulling out the auger and the casing, the ground is stirred by the auger and cement milk is injected into the ground. Thereby, the existing pile removal and backfilling portion 14 of the existing pile 10 is backfilled with a predetermined strength.

[0034] Further, as another construction method for the existing pile removal and backfilling portion 14, for example, as in the construction method disclosed in Patent Document 4 (hereinafter referred to as the "wheel throwing screw stirring method"), a casing is driven around the existing pile 10 to form the drilling portion 12, and after the casing is pulled out, the existing pile 10 is pulled out. Next, while inserting an auger having a diameter equal to or larger than that of the drilling portion 12, the ground is stirred by the auger and cement milk or the like is injected into the ground. Thereby, the existing pile removal and backfilling portion 14 of the existing pile 10 is backfilled with a predetermined strength.

[0035] Here, the existing pile removal and backfilling portion 14 desirably has a predetermined strength. This predetermined strength is set to be approximately equal to the strength of the original ground as an example. Also, the strength of the existing pile removal and backfilling portion 14 is evaluated by, for example, the N-value or the uniaxial compressive strength.

[0036] In addition, examples of the construction method capable of controlling the existing pile removal and backfilling portion 14 to a predetermined strength include the improved wheel throwing method, the wheel throwing screw agitation method, the PG method, the CD method (full rotation all casing method), etc. mentioned above.

[0037] (Newly installed precast pile) The newly installed precast pile 20 is made of a steel pile (steel pipe pile) or a concrete pile and is manufactured in a factory or the like. Also, the newly installed precast pile 20 is constructed by the pre-boring method or the like. FIG. 3 shows, as an example, the newly installed precast pile 20 constructed by the pre-boring and enlarged root consolidation method.

[0038] In the pre-boring and enlarged root consolidation method, first, a new pile shaft boring portion 30 is created in the ground G by a boring rod 40 (see FIG. 5), and a new pile root consolidation boring portion 32 is created at the lower end portion of the new pile shaft boring portion 30. Next, a consolidation liquid W2 is injected into the new pile root consolidation boring portion 32, and while pulling out the boring rod 40, a circumferential pile fixing liquid W1 is injected into the new pile shaft boring portion 30. Next, the newly installed precast pile 20 is dropped into the new pile shaft boring portion 30 and the new pile root consolidation boring portion 32. Thereby, the newly installed precast pile 20 is constructed.

[0039] The new pile root consolidation boring portion 32 may be provided as necessary and can be appropriately changed.

[0040] Here, when constructing the newly installed precast pile 20, for example, the eccentricity of the newly installed precast pile 20 (new pile shaft boring portion 30) is controlled. As shown in FIG. 4, the eccentricity R of the newly installed precast pile 20 is represented by the displacement amount (deviation amount) of the plane position (x, y) of the center (center) C1 of the newly installed precast pile 20 with respect to the design center C0 of the newly installed precast pile 20, and is obtained by the following formula (1).

Equation

[0041] The planar position (x, y) of the center C1 of the newly installed precast pile 20 is measured, for example, as shown in FIG. 5, by drilling holes in the newly installed pile shaft hole portion 30 and the newly installed pile root consolidation hole portion 32 with a drilling rod 40, and when the lower end of the drilling rod 40 reaches the planned depth (drilling lower end), on the ground surface of the ground G, the planar position (planar coordinates) of the center of the drilling rod 40 is measured by an optical wave transit 42 or the like.

[0042] Note that the measurement timing and measurement method of the planar position (x, y) of the center C1 of the newly installed precast pile 20 can be changed as appropriate.

[0043] Here, the eccentricity R of the newly installed precast pile 20 varies depending on the lap rate between the existing pile removal and backfilling portion 14 and the newly installed pile shaft hole portion 30 formed in the ground G when the newly installed precast pile 20 is installed at the planned position. Therefore, the pile design device 50 according to the present embodiment calculates the lap rate between the existing pile removal and backfilling portion 14 and the newly installed pile shaft hole portion 30.

[0044] The lap rate L between the existing pile removal and backfilling portion 14 and the newly installed pile shaft hole portion 30 is obtained by the following formula (2). Lap rate L [%] = (overlap amount d of the existing pile removal and backfilling portion and the newly installed pile shaft hole portion / newly installed pile shaft hole diameter D2 of the newly installed pile shaft hole portion) × 100 ··· (2)

[0045] As shown in FIG. 1, the overlap amount d of the existing pile removal and backfilling portion 14 and the newly installed pile shaft hole portion 30 is the maximum length in the radial direction of the newly installed pile shaft hole portion 30 at the portion where the existing pile removal and backfilling portion 14 and the newly installed pile shaft hole portion 30 overlap in plan view.

[0046] Further, as shown in FIG. 6, when the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 do not overlap in plan view, the overlapping amount d of the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is set to the shortest distance (outer end distance) between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30. Also, when the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 do not overlap in plan view, the wrap rate L is set to negative (minus).

[0047] Note that the existing pile removal and backfilling diameter (diameter) D1 of the existing pile removal and backfilling portion 14 is, for example, the largest in diameter among the excavation equipment such as casings and augers used during construction. Also, the new pile shaft portion drilling diameter D2 of the new pile shaft portion drilling portion 30 is, for example, the diameter of the new pile shaft portion drilling portion 30 on the ground surface of the ground (construction ground) G.

[0048] FIG. 7 shows, as an example, a graph indicating the relationship between the wrap rate L [%] of the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 and the eccentricity R [mm] of the drilling rod 40 for constructing the new pile shaft portion drilling portion 30. In FIG. 7, as described above, the existing pile removal and backfilling portion 14 is constructed by various construction methods capable of controlling the existing pile removal and backfilling portion 14 to a predetermined strength.

[0049] The allowable value of the wrap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is set based on, for example, the allowable value of the eccentricity R of the new prefabricated pile 20 (hereinafter referred to as the "allowable eccentricity").

[0050] Specifically, in the graph shown in FIG. 7, when the allowable eccentricity of the new prefabricated pile 20 is 200 [mm], the wrap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is in the range of 10 [%] or more and 30 [%] or less (10 - 30 [%]), and will exceed the allowable eccentricity of the new prefabricated pile 20. That is, the allowable value of the wrap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is less than 10 [%] or more than 30 [%]. This is presumably because due to the strength difference between the existing pile removal and backfilling portion 14 and the surrounding ground G, the drilling rod 40 (see FIG. 5) for constructing the new pile shaft portion drilling portion 30 is likely to bend.

[0051] (Hardware Configuration of the Pile Design Device) Next, the hardware configuration of the pile design device 50 will be described.

[0052] As shown in FIG. 8, the pile design device 50 includes components such as a CPU (Central Processing Unit) 52, a ROM (Read Only Memory) 54, a RAM (Random Access Memory) 56, a storage 58, an input unit 60, a display unit 62, and a communication interface (I / F) 64. Each component is connected to be communicable with each other via a bus 66.

[0053] The CPU 52 is a central arithmetic processing unit that executes various programs and controls each part. That is, the CPU 52 reads a program from the ROM 54 or the storage 58 and executes the program using the RAM 56 as a working area. The CPU 52 performs control of the above components and various arithmetic processes according to the program recorded in the ROM 54 or the storage 58. Note that the CPU 52 is an example of a processor and a control unit.

[0054] The ROM 54 stores various information processing programs and various data. The RAM 56 temporarily stores a program or data as a working area of the CPU 52. Note that the RAM 56 is an example of a storage unit.

[0055] The storage 58 is composed of an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs including an operating system and various data. Also, a pile design program is stored in the ROM 54 or the storage 58. Note that the pile design program is an example of an information processing program.

[0056] The input unit 60 includes a pointing device such as a mouse and a keyboard, and is used to perform various inputs. The display unit 62 is, for example, a liquid crystal display, and displays various information. The display unit 62 may adopt a touch panel method and function as the input unit 60.

[0057] The communication I / F 64 is an interface for communicating with other devices. For example, standards such as Ethernet (registered trademark), FDDI, Wi-Fi (registered trademark), etc. are used.

[0058] (Function of the pile design device) Next, the functions of the pile design device 50 will be described.

[0059] As shown in FIG. 9, when the pile design device 50 executes the aforementioned pile design program, it uses the above-mentioned hardware resources to realize various functions. Specifically, the pile design device 50 functionally includes an information acquisition unit 70, a wrapping rate calculation unit 72, an existing pile removal and backfilling diameter calculation unit 74, a new pile planned position calculation unit 76, and a new pile shaft part boring diameter calculation unit 78.

[0060] (Information acquisition unit) The information acquisition unit 70 acquires position information (plane position information) of the existing pile removal and backfilling part 14, the new precast pile 20, and the new pile shaft part boring part 30, and various specification information such as the existing pile removal and backfilling diameter D1 and the new pile shaft part boring diameter D2.

[0061] Specifically, the information acquisition unit 70 acquires, for example, the existing pile removal and backfilling part 14, the new precast pile 20, and the new pile shaft part boring part 30 input to the pile design device 50 by the designer via the input unit 60, and various specification information such as the existing pile removal and backfilling diameter D1 and the new pile shaft part boring diameter D2.

[0062] In addition, the information acquisition unit 70 acquires information on whether the existing pile removal and backfilling diameter D1, the new pile shaft part boring diameter D2, and the planned position of the new precast pile 20 can be changed.

[0063] Specifically, the information acquisition unit 70 acquires, for example, information on whether the existing pile removal and backfilling diameter D1, the new pile shaft boring diameter D2, and the changeability of the planned position of the new precast pile 20, which are input into the pile design device 50 via the input unit 60 by the designer.

[0064] (Wrapping rate calculation unit) The wrapping rate calculation unit 72 calculates the wrapping rate L of the existing pile removal and backfilling part 14 and the new pile shaft boring part 30 based on the above formula (2).

[0065] (Existing pile removal and backfilling diameter calculation unit) The existing pile removal and backfilling diameter calculation unit 74 determines whether the existing pile removal and backfilling diameter D1 can be changed based on the information on whether the existing pile removal and backfilling diameter D1 can be changed. Then, when the wrapping rate L calculated by the wrapping rate calculation unit 72 is outside the allowable value and it is determined that the existing pile removal and backfilling diameter D1 can be changed, the existing pile removal and backfilling diameter calculation unit 74 calculates (inverse calculates) the existing pile removal and backfilling diameter D1 at which the wrapping rate L of the existing pile removal and backfilling part 14 and the new pile shaft boring part 30 becomes the allowable value based on the above formula (2).

[0066] Specifically, for example, in the embodiment shown in FIG. 10(A), the existing pile removal and backfilling diameter D1 of the existing pile removal and backfilling part 14 is increased so that the wrapping rate L of the existing pile removal and backfilling part 14 and the new pile shaft boring part 30 exceeds 30 [%]. In this case, the existing pile removal and backfilling diameter calculation unit 74 calculates, for example, the minimum existing pile removal and backfilling diameter D1 at which the wrapping rate L exceeds 30 [%] based on the above formula (2).

[0067] On the other hand, in the embodiment shown in FIG. 10(B), the existing pile removal and backfilling diameter D1 of the existing pile removal and backfilling part 14 is decreased so that the wrapping rate L of the existing pile removal and backfilling part 14 and the new pile shaft boring part 30 is less than 10 [%]. In this case, the existing pile removal and backfilling diameter calculation unit 74 calculates, for example, the maximum existing pile removal and backfilling diameter D1 at which the wrapping rate L is less than 10 [%] based on the above formula (2).

[0068] (New pile planned position calculation unit) The newly installed pile planned position calculation unit 76 determines whether the planned position of the newly installed precast pile 20 can be changed based on the information on whether the planned position can be changed. Then, when the wrap rate L calculated by the wrap rate calculation unit 72 is outside the allowable value and it is determined that the planned position of the newly installed precast pile 20 can be changed, the newly installed pile planned position calculation unit 76 calculates (by inverse calculation) the planned position of the newly installed precast pile 20 at which the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 becomes the allowable value based on the above formula (2), that is, the center-to-center distance between the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30.

[0069] Specifically, for example, in the embodiment shown in FIG. 11(A), the planned position of the newly installed precast pile 20 is changed to a position away from the existing pile removal and backfilling unit 14 so that the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 is less than 10%. In this case, the newly installed pile planned position calculation unit 76 calculates, for example, the maximum center-to-center distance T at which the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 is less than 10% based on the above formula (2).

[0070] On the other hand, in the embodiment shown in FIG. 11(B), the planned position of the newly installed precast pile 20 is changed to a position close to the existing pile removal and backfilling unit 14 so that the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 exceeds 30%. In this case, the newly installed pile planned position calculation unit 76 calculates, for example, the minimum center-to-center distance T at which the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 exceeds 30% based on the above formula (2).

[0071] (Newly installed pile shaft hole diameter calculation unit) The newly installed pile shaft hole diameter calculation unit 78 determines whether the newly installed pile shaft hole diameter D2 can be changed based on the information on whether the newly installed pile shaft hole diameter D2 can be changed. Then, when the wrap rate L calculated by the wrap rate calculation unit 72 is outside the allowable value and it is determined that the newly installed pile shaft hole diameter D2 can be changed, the newly installed pile shaft hole diameter calculation unit 78 calculates (by inverse calculation) the newly installed pile shaft hole diameter D2 at which the wrap rate L of the existing pile removal and backfilling unit 14 and the newly installed pile shaft hole drilling unit 30 becomes the allowable value based on the above formula (2).

[0072] Specifically, for example, in the embodiment shown in FIG. 12(A), the new pile shaft boring diameter D2 of the new pile shaft boring portion 30 is increased so that the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft boring portion 30 exceeds 30%. In this case, the new pile shaft boring diameter calculation unit 78 calculates, for example, the minimum new pile shaft boring diameter D2 at which the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft boring portion 30 exceeds 30% based on the above formula (2).

[0073] On the other hand, in the embodiment shown in FIG. 12(B), the new pile shaft boring diameter D2 of the new pile shaft boring portion 30 is decreased so that the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft boring portion 30 is less than 10%. In this case, the new pile shaft boring diameter calculation unit 78 calculates, for example, the maximum new pile shaft boring diameter D2 at which the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft boring portion 30 is less than 10% based on the above formula (2).

[0074] (Function) Next, while explaining the operation of the pile design device 50, an example of the pile design method will be described.

[0075] As preliminary preparation, the designer first examines the existing piles 10. Specifically, the designer checks the arrangement of the existing piles 10 within the site. Next, after removing the existing piles 10, the designer checks whether there is construction of new precast piles 20. Then, when there is construction of new precast piles 20 after removing the existing piles 10, the designer checks the positions where the new precast piles 20 interfere with the existing piles 10. Next, the existing piles 10 to be removed are determined. Next, the method for removing and backfilling the existing piles 10 is selected and determined.

[0076] Also, in parallel with the examination of the existing piles 10 described above, the designer also examines the new precast piles 20. Specifically, the designer examines the pile diameter, pile length, etc. of the new precast piles 20. Next, the construction method of the new precast piles 20 is selected and determined.

[0077] Next, the designer inputs, for example, the position information (planar position information) of the existing pile removal and backfilling part 14, the newly installed prefabricated pile 20, and the newly installed pile shaft part drilling part 30, and various specification information such as the existing pile removal and backfilling diameter D1 and the newly installed pile shaft part drilling diameter D2 into the pile design device 50 via the input unit 60. Also, the designer inputs, via the input unit 60, the information on whether the existing pile removal and backfilling diameter D1, the newly installed pile shaft part drilling diameter D2, and the plan position of the newly installed prefabricated pile 20 can be changed into the pile design device 50. In this state, when the designer executes the pile design device 50, the pile design process shown in FIG. 13 is executed. Note that the pile design process is an example of a pile design method.

[0078] As shown in FIG. 13, first, in step S10, the CPU 52 acquires the position information (planar position information) of the existing pile removal and backfilling part 14, the newly installed prefabricated pile 20, and the newly installed pile shaft part drilling part 30, and various specification information such as the existing pile removal and backfilling diameter D1 and the newly installed pile shaft part drilling diameter D2.

[0079] Next, in step S12, the CPU 52 calculates the lap rate L of the existing pile removal and backfilling part 14 and the newly installed pile shaft part drilling part 30 based on the above formula (2).

[0080] Next, in step S14, the CPU 52 determines whether the calculated lap rate L is within the allowable value. And when the CPU 52 determines that the calculated lap rate L is within the allowable value, it proceeds to step S16. In step S16, the CPU 52 displays a message indicating that the lap rate L is within the allowable value on the display unit 62 and ends the process.

[0081] On the other hand, in step S14, when the CPU 52 determines that the calculated lap rate L is outside the allowable value, it proceeds to step S18. Next, in step S18, the CPU 52 acquires the information on whether the existing pile removal and backfilling diameter D1 can be changed.

[0082] Next, in step S20, the CPU 52 determines whether the existing pile removal and backfilling diameter D1 can be changed. And when the CPU 52 determines that the existing pile removal and backfilling diameter D1 can be changed, it proceeds to step S22.

[0083] Next, in step S22, the CPU 52 calculates (backsolves) the existing pile removal and backfilling diameter D1 at which the lap rate L becomes the allowable value based on the above formula (2). Next, in step S16, the CPU 52 displays the calculated existing pile removal and backfilling diameter D1, etc. on the display unit 62 and ends the process.

[0084] On the other hand, in step S20, when the CPU 52 determines that the existing pile removal and backfilling diameter D1 cannot be changed, it proceeds to step S24. In step S24, the CPU 52 acquires information on whether the planned position of the newly installed prefabricated pile 20 can be changed.

[0085] Next, in step S26, the CPU 52 determines whether the planned position of the newly installed prefabricated pile 20 can be changed. And when the CPU 52 determines that the planned position of the newly installed prefabricated pile 20 can be changed, it proceeds to step S28.

[0086] Next, in step S28, the CPU 52 calculates (backsolves) the planned position of the newly installed prefabricated pile 20 at which the lap rate L becomes the allowable value based on the above formula (2). Next, in step S16, the CPU 52 displays the calculated planned position of the newly installed prefabricated pile 20, etc. on the display unit 62 and ends the process.

[0087] On the other hand, in step S26, when the CPU 52 determines that the planned position of the newly installed prefabricated pile 20 cannot be changed, it proceeds to step S30. In step S30, the CPU 52 acquires information on whether the bored diameter D2 of the new pile shaft can be changed.

[0088] Next, in step S32, the CPU 52 determines whether the bored diameter D2 of the new pile shaft can be changed. And when the CPU 52 determines that the bored diameter D2 of the new pile shaft can be changed, it proceeds to step S34.

[0089] Next, in step S34, the CPU 52 calculates (backsolves) a new bored diameter D2 of the new pile shaft portion such that the wrapping rate L becomes an allowable value based on the above formula (2). Next, in step S16, the CPU 52 displays the calculated new bored diameter D2 of the new pile shaft portion and the like on the display unit 62 and ends the process.

[0090] On the other hand, in step S32, when the CPU 52 determines that the planned position of the new precast pile 20 cannot be changed, it proceeds to step S16. Next, in step S16, the CPU 52 displays a message or the like indicating that the wrapping rate L is outside the allowable value on the display unit 62 and ends the process.

[0091] (Function and Effect) Next, the function and effect of the present embodiment will be described.

[0092] As described above, when the wrapping rate L between the existing pile removal and backfill portion 14 formed by backfilling the bored portion 12 after removal of the existing pile 10 and the new pile shaft bored portion 30 formed in the ground G when the new precast pile 20 is newly installed at the planned position is outside the allowable value, the eccentricity of the new pile shaft bored portion 30 may increase. As a result, the construction accuracy of the new precast pile 20 may decrease.

[0093] In contrast, in the pile design device 50 according to the present embodiment, the CPU 52 calculates the wrapping rate L between the existing pile removal and backfill portion 14 and the new pile shaft bored portion 30, and determines whether the calculated wrapping rate L is an allowable value. When the determination result of the wrapping rate L is outside the allowable value, the CPU 52 first acquires information on whether the existing pile removal and backfill diameter D1 of the existing pile removal and backfill portion 14 can be changed.

[0094] When the information on whether the existing pile removal and backfill diameter D1 can be changed indicates that it can be changed, the CPU 52 calculates an existing pile removal and backfill diameter D1 such that the wrapping rate L between the existing pile removal and backfill portion 14 and the new pile shaft bored portion 30 becomes an allowable value.

[0095] Also, when the information on whether the existing pile removal and backfilling diameter D1 can be changed is non-changeable, the CPU 52 acquires the information on whether the planned position of the new prefabricated pile 20 can be changed. And when the information on whether the planned position of the new prefabricated pile 20 can be changed is changeable, the CPU 52 calculates the planned position of the new prefabricated pile 20 at which the wrap rate L between the existing pile removal and backfilling part 14 and the new pile shaft part drilling part 30 becomes the allowable value.

[0096] Furthermore, when the information on whether the planned position of the new prefabricated pile 20 can be changed is non-changeable, the CPU 52 acquires the information on whether the diameter D2 of the new pile shaft part drilling of the new pile shaft part drilling part 30 can be changed. And when the information on whether the diameter D2 of the new pile shaft part drilling can be changed is changeable, the CPU 52 calculates the diameter D2 of the new pile shaft part drilling at which the wrap rate L between the existing pile removal and backfilling part 14 and the new pile shaft part drilling part 30 becomes the allowable value.

[0097] Thus, in this embodiment, by changing the existing pile removal and backfilling diameter D1, the planned position of the new prefabricated pile 20, or the diameter D2 of the new pile shaft part drilling, the wrap rate L between the existing pile removal and backfilling part 14 and the new pile shaft part drilling part 30 can be easily made to be the allowable value.

[0098] (Modification example) Next, a modification example of the above embodiment will be described.

[0099] In the above embodiment, when the wrap rate L between the existing pile removal and backfilling part 14 and the new pile shaft part drilling part 30 is outside the allowable value, the change of the existing pile removal and backfilling diameter D1, the planned position of the new prefabricated pile 20, and the diameter D2 of the new pile shaft part drilling is considered in this order so that the wrap rate L becomes the allowable value. However, the order of considering the change of the existing pile removal and backfilling diameter D1, the planned position of the new prefabricated pile 20, and the diameter D2 of the new pile shaft part drilling can be changed as appropriate.

[0100] In the above-described embodiment, when the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is outside the allowable value, the existing pile removal and backfilling diameter D1, the planned position of the new prefabricated pile 20, or the new pile shaft portion drilling diameter D2 is changed so that the lap rate L becomes the allowable value. However, the above-described embodiment is not limited to the existing pile removal and backfilling diameter D1, the planned position of the new prefabricated pile 20, and the new pile shaft portion drilling diameter D2. For example, the pile diameter P of the new prefabricated pile 20 may be changed.

[0101] For example, in the modification shown in FIG. 14(A), the pile diameter P of the new prefabricated pile 20 is reduced so that the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is less than 10%, thereby reducing the new pile shaft portion drilling diameter D2 of the new pile shaft portion drilling portion 30. In this case, the new pile shaft portion drilling diameter calculation unit 78 calculates, for example, the maximum new pile shaft portion drilling diameter D2 at which the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 is less than 10% based on the above formula (2).

[0102] On the other hand, in the modification shown in FIG. 14(B), the pile diameter P of the new prefabricated pile 20 is increased so that the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 exceeds 30%, thereby increasing the new pile shaft portion drilling diameter D2 of the new pile shaft portion drilling portion 30. In this case, the new pile shaft portion drilling diameter calculation unit 78 calculates, for example, the new pile shaft portion drilling diameter D2 at which the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft portion drilling portion 30 exceeds 30% based on the above formula (2).

[0103] Here, when the pile diameter P of the new prefabricated pile 20 is changed as in the embodiment shown in FIG. 12(B) and the modifications shown in FIGS. 14(A) and 14(B), the vertical supporting force and the horizontal bearing capacity of the new prefabricated pile 20 also vary. Therefore, when the pile diameter P of the new prefabricated pile 20 is changed, the new prefabricated pile 20 may be redesigned. In particular, when the pile diameter P of the new prefabricated pile 20 is reduced as in the embodiments shown in FIGS. 12(B) and 14(A), there is a possibility that the vertical supporting force and the horizontal bearing capacity of the new prefabricated pile 20 are insufficient.

[0104] Therefore, when redesigning the newly installed precast pile 20, for example, measures such as increasing the diameter D3 (see Fig. 3) of the bored hole part 32 of the newly installed pile foundation consolidation part, increasing the pile length of the newly installed precast pile 20, changing the pile type of the newly installed precast pile 20, and changing the shape of the newly installed precast pile 20 can be taken to supplement the insufficient vertical supporting force and horizontal bearing capacity of the newly installed precast pile 20.

[0105] As an example of changing the pile type of the newly installed precast pile 20, for example, when the newly installed precast pile 20 is a PRC pile (prestressed reinforced concrete pile), by increasing the wall thickness of the newly installed precast pile 20 or increasing the diameter of the reinforcing bars of the reinforcing bars, the bending moment and shear bearing capacity of the newly installed precast pile 20 can be increased.

[0106] Also, as another example of changing the pile type of the newly installed precast pile 20, for example, when the newly installed precast pile 20 is a PHC pile (pretensioned centrifugal high-strength prestressed concrete pile), it is conceivable to change the newly installed precast pile 20 to a PRC pile with a large amount of axial reinforcing bars.

[0107] Note that examples of the pile type of the newly installed precast pile 20 include, for example, RC piles (centrifugal reinforced concrete piles), PHC piles, SC piles (concrete piles with outer steel pipes), PRC piles, etc. Also, examples of the shape of the newly installed precast pile 20 include ST piles (tip-expanded PHC piles) and joint piles (jointed PHC piles).

[0108] Also, when the pile diameter P of the newly installed precast pile 20 is increased, the vertical supporting force and horizontal bearing capacity of the newly installed precast pile 20 may become excessive and uneconomical. Even in such cases, it is preferable to redesign the newly installed precast pile 20.

[0109] Also, a redesign part for redesigning the newly installed precast pile 20 may be provided in the pile design device 50, and in the said redesign part, the pile diameter P, pile length, pile type, shape of the newly installed precast pile 20 that satisfy a predetermined vertical supporting force and horizontal bearing capacity, the diameter D3 (see Fig. 3) of the bored hole part 32 of the newly installed pile foundation consolidation part, etc. may be calculated.

[0110] Further, when the lap rate L between the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 is outside the allowable value, at least one of the existing pile removal and backfilling diameter D1, the planned position of the new precast pile 20, the new pile shaft hole drilling diameter D2, and the pile diameter P of the new precast pile 20 may be changed so that the lap rate L becomes the allowable value.

[0111] Also, the allowable value of the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 can be changed as appropriate. For example, in the graph of FIG. 7, when the allowable eccentricity of the new precast pile 20 is 100 [mm], the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 is in the range of 0 to 60 [%], and the allowable eccentricity of the new precast pile 20 will be exceeded. That is, the allowable value of the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 is more than 60 [%].

[0112] Also, the allowable value of the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 may be more than 60 [%], less than 10 [%], or more than 30 [%].

[0113] In the above embodiment, the allowable value of the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 is set based on the allowable eccentricity of the new precast pile 20. However, the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 can be set based on at least one of, for example, the allowable eccentricity of the new precast pile 20 and the allowable eccentricity of the drilling rod 40. Further, the lap rate L of the existing pile removal and backfilling portion 14 and the new pile shaft hole drilling portion 30 is not limited to the allowable eccentricity of the new precast pile 20, and may be set based on, for example, other indicators indicating the construction accuracy of the new precast pile 20.

[0114] Also, in the above embodiment, the processor refers to a processor in a broad sense, including a general-purpose processor (such as a CPU, etc.) and a dedicated processor (such as a GPU: Graphics Processing Unit, an ASIC: Application Specific Integrated Circuit, an FPGA: Field Programmable Gate Array, a programmable logic device, etc.).

[0115] Moreover, the operation of the processor in the above embodiment may be achieved not only by one processor but also by a plurality of physically separated processors cooperating. Also, the order of each operation of the processor is not limited to the order described in the above embodiment and may be changed as appropriate.

[0116] Also, in the above embodiment, the form in which each program is installed in the ROM or the storage is described, but it is not limited thereto. Each program according to the above embodiment may be provided in a form recorded on a computer-readable storage medium. For example, each program according to the above embodiment may be provided in a form recorded on an optical disk such as a CD (Compact Disc)-ROM and a DVD (Digital Versatile Disc)-ROM, or in a form recorded on a semiconductor memory such as a USB (Universal Serial Bus) memory and a memory card. Also, each program according to the above embodiment may be acquired from an external device via a communication I / F.

[0117] Also, in the above embodiment, the case where the processing in the pile design device 50 is realized by a software configuration using a computer by executing a program is described, but the present disclosure is not limited thereto. For example, the processing in the pile design device 50 may be realized in a form by a hardware configuration or a combination of a hardware configuration and a software configuration.

[0118] In addition, the configuration of the pile design device 50 described in the above embodiment is merely an example, and it goes without saying that unnecessary parts may be deleted or new parts may be added within the scope not departing from the gist of the present disclosure.

[0119] Also, the processing flow in the pile design device 50 described in the above embodiment is merely an example, and it goes without saying that unnecessary steps may be deleted, new steps may be added, or the processing order may be changed within the scope not departing from the gist of the present disclosure.

[0120] As described above, one embodiment of the present invention has been explained. However, the present invention is not limited to such an embodiment, and one embodiment and various modified examples may be appropriately combined and used, and it goes without saying that the present invention can be implemented in various modes within the scope not departing from the gist of the present invention.

Explanation of Reference Numerals

[0121] 10 Existing pile 12 Drilled hole part 14 Existing pile removal and backfilling part D1 Existing pile removal and backfilling diameter 20 Newly installed prefabricated pile P Pile diameter of the newly installed prefabricated pile 30 Drilled hole part of the newly installed pile shaft D2 Drilled hole diameter of the newly installed pile shaft

Claims

1. Calculate the lap rate between the existing pile removal and backfilling part formed by backfilling the drilled hole after removing the existing pile, and the newly installed pile shaft drilled hole part formed in the ground when installing a newly installed precast pile at the planned position, Determine whether the calculated lap rate is within the allowable value, A pile design program that causes a computer to execute the process.

2. When the lap rate is outside the allowable value, obtain information on whether it is possible to change the diameter of the existing pile removal and backfilling part of the existing pile removal and backfilling part, When the information on whether it is possible to change the diameter of the existing pile removal and backfilling part allows for a change, calculate the diameter of the existing pile removal and backfilling part at which the lap rate becomes the allowable value, The pile design program according to claim 1, which causes a computer to execute the process.

3. When the lap rate is outside the allowable value, obtain information on whether it is possible to change the planned position of the newly installed precast pile, When the information on whether it is possible to change the planned position of the newly installed precast pile allows for a change, calculate the planned position of the newly installed precast pile at which the lap rate becomes the allowable value, The pile design program according to claim 1, which causes a computer to execute the process.

4. When the lap rate is outside the allowable value, obtain information on whether it is possible to change the diameter of the newly installed pile shaft drilled hole part of the newly installed pile shaft drilled hole part, When the information on whether it is possible to change the diameter of the newly installed pile shaft drilled hole part allows for a change, calculate the diameter of the newly installed pile shaft drilled hole part at which the lap rate becomes the allowable value, The pile design program according to claim 1, which causes a computer to execute the process.

5. Calculate the lap rate between the existing pile removal and backfilling part formed by backfilling the drilled hole after removing the existing pile, and the newly installed pile shaft drilled hole part formed in the ground when installing a newly installed precast pile at the planned position, Determine whether the calculated lap rate is within the allowable value, A pile design device including a control unit that executes the process.

6. Calculate the lap rate between the existing pile removal and backfilling part formed by backfilling the drilled hole after removing the existing pile, and the newly installed pile shaft drilled hole part formed in the ground when installing a newly installed precast pile at the planned position, Determine whether the calculated lap rate is within the allowable value, A pile design method executed by a computer.

Images