JP4504752B2 - Construction method and apparatus for tubular precast concrete member - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a construction method and a construction apparatus in the case where a cylindrical precast concrete member (caisson or well) is submerged in the ground.

  Conventionally, in general, when a cylindrical precast concrete member frame (caisson or well) is submerged from the ground (or on the water) to the ground (or in the bottom of the ground), a base frame is placed around the tubular precast concrete member to be constructed. An underground anchor that supports the reaction force of subsidence of the cylindrical precast concrete member is installed and coupled to the base frame, and the cylindrical precast concrete member is subsidized on the basis of the base frame. When providing a base frame on the water, perform the required pile driving and fix the base frame to the top of the pile.

  The settlement of the tubular precast concrete member is performed by pressing the tubular precast concrete member downward from above while excavating the ground in the tubular member. The tubular precast concrete member has a blade edge at the lower end, and the blade edge bites into the ground as the ground is excavated in the tubular member, and enters the ground along the planned set line.

  As such a technique, the ground is excavated by using an excavation bucket having a swivel bending arm operated from the ground, and a push-down device is attached to the upper part of the cylindrical precast concrete member driving body to set the cylindrical precast concrete member. There is a technique (for example, refer to Patent Document 1).

  This technique is a technique for sinking a cylindrical precast concrete member in a relatively soft formation.

  As the tubular precast concrete member sinks, the tubular precast concrete member is sequentially added to the upper end of the tubular precast concrete member housing. The addition of the tubular precast concrete member is performed by forming the tubular precast concrete member with cast-in-place concrete or sequentially stacking the precast concrete segments.

  Since cast-in-place concrete requires a long time for rebar assembly, form attachment / removal, concrete placement, concrete curing, etc., precast concrete segments are often used recently from the viewpoint of quick construction and quality control.

  When the subsidence area is a soft stratum, the bottom of the tubular precast concrete member is excavated and soiled using a grab bucket suspended from a ground crane. Do subsidence.

  When the formation on which the cylindrical precast concrete member is sunk is a hard formation, a drilling device for rock excavation is used. For example, a drill casing is inserted into a tubular precast concrete member, a drilling blade planted at the lower end of the drill casing, and a side portion and a bottom portion of a diameter-enlarged blade that is axially attached to the outer periphery of the drill casing so as to be able to expand within a predetermined angle There is a technique of performing excavation under the cutting edge of the cylindrical precast concrete member with the excavating blade planted in the plant, and sinking while controlling the settlement of the cylindrical precast concrete member (for example, see Patent Document 2).

  In addition, when excavating a vertical hole having a diameter of several meters in a hard formation made of hard rock or the like, the present inventors repeat the excavation of various intermediate diameters according to the situation of the formation, A powerful diameter-expanding rotary excavator equipped with a bit capable of expanding and contracting capable of excavating a vertical hole has been developed and provided (see, for example, Patent Document 3).

  This diameter-expanded rotary excavator is attached to the lower end of a casing pipe suspended in a tubular precast concrete member. And in the upper space of the cylindrical precast concrete member, an all-round rotation drive unit is installed on the outer periphery of the casing pipe, and this all-around rotation drive unit grips the outer periphery of the casing pipe and installs the enlarged diameter rotary excavator through the casing pipe. To drive. The excavated soil is discharged to the ground by a grab bucket connected to a crane rope above and below the casing pipe.

  As the cylindrical precast concrete member sinks, it is necessary to add a casing pipe and a cylindrical precast concrete member frame. It is preferable to use a precast concrete segment as a frame to be added to the upper end of the tubular precast concrete member, and to perform rapid construction. In this case, in order to perform addition of the casing pipe and the addition of the tubular precast concrete member segment, each time of the addition, removal of the all-round rotation drive unit, disassembly, removal of the pressure beam for mounting and installation of the tubular precast concrete member, It is necessary to install.

  The all-round rotation drive unit has a mass of about 50 tons, and the cylindrical precast concrete member segment also has a mass of 30 to 50 tons depending on the scale. In order to add the precast concrete member segments, it is necessary to always arrange a large crane having a lifting capacity of 50 tons or more around the cylindrical precast concrete member setting position.

Since the mass of the hammer grab bucket is about 2 to 3 tons and the mass of one casing pipe to be added is about 5 tons, a small crane is sufficient to perform these operations.
Japanese Patent Laid-Open No. 4-64620 Japanese Patent Laid-Open No. 10-317376 Application for Japanese Patent Application No. 2003-36639

  When excavating bedrock using a large-diameter rotary excavator, when sinking a cylindrical precast concrete member frame, an all-round rotary drive that rotates the enlarged rotary excavator is attached to the upper end of the casing pipe above the ground. Has been.

  In such a case, the present invention simply and quickly attaches and removes (replaces) the entire circumference rotation drive unit without using a large crane when adding a casing pipe and a cylindrical precast concrete member segment. It is an object of the present invention to provide a method for constructing a tubular precast concrete member that can be constructed quickly.

  The present invention also eliminates the need to disassemble, remove, and mount the tubular precast concrete member pressure beam by moving the tubular precast concrete member pressure beam along with the entire circumference rotation drive unit. The tubular precast concrete member segments are joined to the precast concrete member pressure beam and moved so that the casing pipe can be added simultaneously during the joining work process, further reducing the process. Provide the technology that made it possible.

  The present invention has been made to solve the above problems, and is a method for constructing a tubular precast concrete member characterized by taking the following technical means. That is, the method of the present invention is a method for constructing a tubular precast concrete member in which the tubular precast concrete member is laid in a hard rock, and includes the following steps.

  (A) A large-diameter rotary excavator is suspended in a cylindrical precast concrete member through a casing pipe having an all-round rotation drive unit at the upper end to excavate hard ground.

  (B) Each time the cylindrical precast concrete member sinks by the depth of one cylindrical precast concrete member segment, the casing pipe is cut off below the entire circumference rotation drive unit. At the same time, the tip of the cylindrical precast concrete member pressure-reducing jack attached to the cylindrical precast concrete member pressure beam is separated from the base frame.

  (C) The integral block which consists of the separated casing pipe, the said all-around rotation drive part, and a cylindrical precast concrete member pressurization beam is moved laterally.

  (D) An operation of attaching the waiting cylindrical precast concrete member segment to the laterally moved cylindrical precast concrete member pressure beam is performed, and this operation and the connecting operation of the extension portion of the casing pipe are performed simultaneously in parallel.

  (E) Returning the integrated block in which the tubular precast concrete member segment is attached to the tubular precast concrete member pressure beam to the position where the tubular precast concrete member is set, and connecting the casing pipe and the base of the tubular precast concrete member reduction jack Connect to the frame.

  The steps (b) to (e) are repeated to sink the cylindrical precast concrete member segment.

  According to the present invention, the repositioning of the all-round rotation drive unit performed when the casing pipe is added and the cylindrical precast concrete member segment is added is not lifted by using a large crane, but is moved laterally on the frame. A lateral movement device was used. In addition, the precast cylindrical precast concrete member segment to be added on the cylindrical precast concrete member is not lifted up using a large crane, but the cylindrical precast concrete member pressure beam is moved sideways on the frame frame together with the entire circumference rotation drive unit. The cylindrical precast concrete member segment was joined to this and transported to the position where the cylindrical precast concrete member was set. At this time, since the connecting operation of the casing pipe is performed in parallel with the operation of connecting the cylindrical precast concrete member segment to the cylindrical precast concrete member pressurizing beam, the time is saved.

  Other operations such as raising and lowering the club bucket and adding the casing pipe can be performed using a small crane. Therefore, it is not necessary to always arrange a large crane around the cylindrical precast concrete member.

The apparatus of the present invention capable of suitably carrying out the above-described method of the present invention comprises:
(B) Large-diameter rotary excavator for rock excavation suspended down to the bottom bottom of a cylindrical precast concrete member through a casing pipe having an all-round rotation drive unit in the vicinity of the upper end (b) A cylindrical shape from above the cylindrical precast concrete member Frame frame extending laterally to above the standby position of the precast concrete member segment (c) A traveling device for horizontally running on the frame frame while supporting the all-round rotation drive unit and the cylindrical precast concrete member pressure beam. ) Elevating jack attached to the traveling device for raising and lowering the all-round rotation drive unit and the cylindrical precast concrete member pressure beam. (E) The rod tip is detachable from the base frame and attached to the cylindrical precast concrete member pressure beam. A cylindrical plug having a jack for press-fitting a cylindrical precast concrete member A construction unit of the cast concrete member.

  The most characteristic features of the device of the present invention are as follows.

  (1) A frame frame that supports the all-round rotation drive unit in a laterally movable manner is provided on the ground.

(2) Under this frame, a device for entering a carriage for transporting the tubular precast concrete member segment was installed, and the tubular precast concrete member segment was made to wait. (3) Traveling laterally on the frame The cylindrical precast concrete member pressure beam is attached to the apparatus, the cylindrical precast concrete member segment waiting in the standby position is coupled to the cylindrical precast concrete member pressure beam, and this is conveyed onto the cylindrical precast concrete member. What I did.

  (4) The cylindrical precast concrete member pressing jack attached to the cylindrical precast concrete member pressing beam is formed so as to be separable from the base frame.

  According to the present invention, it is possible to arrange a large crane in order to refill the entire circumference rotation drive unit, refill the tubular precast concrete member segment pressure beam, and add the tubular precast concrete member segment. It became unnecessary. In addition, since the work of joining the tubular precast concrete member segment to the pressure beam and the addition of the casing pipe can be performed simultaneously in parallel, the work process is significantly shortened.

  Each process of the construction method of the cylindrical precast concrete member of this invention can be easily implement | achieved by using the construction apparatus of the cylindrical precast concrete member of this invention.

  The construction apparatus for a tubular precast concrete member according to the present invention is provided with a frame that extends laterally from above the tubular precast concrete member to above the standby position of the tubular precast concrete member segment, and travels horizontally on the frame. An all-round rotation drive unit and a cylindrical precast concrete member pressure beam were attached to the traveling device, and the re-circulation of the all-round rotation drive unit and the addition of the tubular precast concrete member segment were greatly facilitated.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall side view showing a construction state of a tubular precast concrete member 10 according to an embodiment of the present invention, and FIG. 2 is a plan view thereof. In the case of underwater construction, a support pile 21 is sunk in an area where the tubular precast concrete member 10 is to be formed, and a base frame 23 is installed on the top 22 of the support pile 21. The support pile 21 is unnecessary on normal ground. A temporary receiving bracket 24 is placed on the base frame 23. The temporary receiving bracket 24 temporarily receives the tubular precast concrete member 10 when joining the tubular precast concrete member segment to the tubular precast concrete member.

  Further, a ground anchor 25 is constructed around the cylindrical precast concrete member 10, and the top portion thereof is coupled to the base frame 23. The ground anchor 25 supports the reaction force of the pushing force when the tubular precast concrete member 10 is pushed into the ground by the press-fitting hydraulic jack 41 coupled to the base frame 23, and prevents the base frame 23 from floating.

  In the excavation process of the normal soil 102 until the hard rock layer 101 is reached, the bottom 12 of the cylindrical precast concrete member 10 is excavated with the hammer grab bucket 14 while the frame 12 of the cylindrical precast concrete member 10 is sequentially added and subsidized. Let The cylindrical precast concrete member 10 pushes down the cylindrical precast concrete member press beam 40 provided on the cylindrical precast concrete member segment 31 on the upper end sequentially with the press-fitting hydraulic jack 41 and sinks. . The press-fit hydraulic jack 41 that pushes down the cylindrical precast concrete member pressurizing beam 40 couples the lower end 42 of the rod to the base frame 23 and supports the reaction force to the ground anchor 25 to apply the pressurizing beam 40 as described above. Press.

  When the lower end 13 of the frame 12 of the tubular precast concrete member 10 reaches the hard rock layer 101, in the present invention, the enlarged rotary excavator 50 having an enlarged bit is suspended in the tubular precast concrete member 10 and the ground. Drilling. The diameter-expanded rotary excavator 50 descends in the cylindrical precast concrete member 10 with the casing pipe 51 in a reduced diameter state, and expands the diameter at the lower bottom portion of the cylindrical precast concrete member 10 to excavate the ground. An all-round rotation drive unit 60 is disposed at the head of the casing pipe 51.

  In the present invention, the frame frame 70 is installed on the base frame 23. The frame 70 is composed of left and right elevated beams 71 as shown in FIG. The left and right elevated beams 71 are provided to extend laterally from columns 72 erected on the base frame 23 of the tubular precast concrete member 10, and a column 73 is provided at the extended end of the elevated beam 71. A carriage 80 that transports the tubular precast concrete member segment 31 travels on the rail 81 and enters the extension span 74 (between the columns 72 and 73). The carriage 80 transports the cylindrical precast concrete member segment 31 to be added and waits in the extension span 74.

  A traveling device 90 is placed on the frame 70. The traveling device 90 travels on the left and right elevated beams 71 and moves from above the tubular precast concrete member 10 to the standby position of the tubular precast concrete member segment 31.

  The cylindrical precast concrete member pressure beam 40 is a beam provided with a ring-shaped pressure portion 44 as shown in a plan view in FIG. The ring-shaped pressurizing portion 44 has a ring shape substantially the same shape as the tubular precast concrete member segment. Press-fit hydraulic jacks 41 are mounted at the four corners. The lower end portion 42 of the rod of the press-fitting hydraulic jack 41 is coupled to the base frame 23, and this coupling is formed to be detachable.

  The traveling device 90 is loaded with a supporting hydraulic jack 61 and an all-round rotation drive unit 60. The lower end of the supporting hydraulic jack 61 is connected to a cylindrical precast concrete member pressure beam 40. Accordingly, the traveling device 90 supports the all-round rotation driving unit 60, the separated upper portion 52 of the casing pipe 51 engaged with the all-round rotation driving unit 60, and the cylindrical precast concrete member pressure beam 40. Yes.

Next, the construction process of the present invention will be described with reference to FIGS.
(1) FIG. 4 shows a state in which a cylindrical precast concrete member is simultaneously installed while excavating a hard formation as indicated by an arrow 55. The newly installed tubular precast concrete member segment 31 lowers the tubular precast concrete member pressing beam 40 as indicated by an arrow 32. This reduction is performed by a press-fit hydraulic jack 41 having a lower end portion 42 connected to the base frame 23. The all-round rotation drive unit 60 holds the casing pipe 52 and rotates it, and the rotational force acts on the diameter-expanding rotary excavator 50 to excavate the rock layer 101 having a hard cutting bit. The hammer grab bucket 14 moves up and down in the casing pipe 51 by the crane 100 and discharges the excavated earth and sand to the ground.

The rod of the supporting hydraulic jack 61 descends as the cylindrical precast concrete member pressurizing beam 40 descends.
(2) FIG. 5 shows a state where the settling of one ring of the cylindrical precast concrete member has been completed from the state shown in FIG. The enlarged-diameter rotary excavator 50 and the tubular precast concrete member pressure beam 40 are lowered accordingly, and the press-fitting hydraulic jack 41 and the supporting hydraulic jack 61 are close to the lowering limit, and a new tubular precast concrete is provided. It is time to add part segments.
(3) FIG. 6 shows a state in which the temporary receiving bracket 24 is attached to the base frame 23 in the state shown in FIG. The step of releasing the connection to the tubular precast concrete member pressurizing beam 40 from the tubular precast concrete member 10 and raising it is shown. The cylindrical precast concrete member pressure beam 40 raises the rod of the supporting hydraulic jack 61 as shown by the arrow 33. Next, the casing pipe 51 is cut off.
(4) In FIG. 7, after the upper casing pipe 52 is cut off, the supporting hydraulic jack 61 is raised, and the upper casing pipe 52 is shown by the arrow 34 using the entire circumference rotation drive unit 60. The traveling device 90 is then moved laterally as indicated by an arrow 35. The traveling device 90 moves on the left and right elevated beams 71 of the frame 70 and moves to a standby position where the tubular precast concrete member segment 31 is on standby.
(5) FIG. 8 shows a process of lowering and adding an additional portion 53 of the casing pipe to the top of the casing pipe 51 as indicated by an arrow 36. Since the extension part 53 of this casing pipe is lightweight, it can be easily added using a small crane 100 for a hammer grab bucket.

On the other hand, the waiting tubular precast concrete member segment 31 is coupled to the lower surface of the tubular precast concrete member pressurizing beam 40 that has moved laterally on the frame 70 and is lifted as indicated by an arrow 37. The tubular precast concrete member segment is lifted by a supporting hydraulic jack 61. This operation can be performed concurrently with the above-described casing pipe addition operation.
(6) FIG. 9 shows a step in which the traveling device 90 returns to the upper side of the cylindrical precast concrete member set position as indicated by an arrow 38. The traveling device 90 moves the entire circumference rotation drive unit 60, the upper casing pipe 51, the cylindrical precast concrete member pressure beam 40, and the cylindrical precast concrete member segment 31. Although these total masses can be as high as 100 tons, it is easy to properly design the frame 70. Large cranes are unnecessary.
(7) FIG. 10 shows a state in which the traveling device 90 has reached the upper position of the cylindrical precast concrete member 10. The upper casing pipe 52 is lowered as shown by an arrow 39 and connected to the upper end of the added casing pipe 53.
(8) Next, as shown in FIG. 11, the tubular precast concrete member segment 31 is lowered together with the tubular precast concrete member pressurizing beam 40 and joined to the top end of the tubular precast concrete member 10. Next, the rod of the press-fitting hydraulic jack 41 is lowered, and the lower end portion 42 of the rod is coupled to the base frame 23.
(9) As shown in FIG. 12, the temporary receiving bracket (24) attached on the base frame 23 is removed, and the setting process of the tubular precast concrete member 10 is resumed.

  As described above, according to the present invention, it is not necessary to always arrange a large crane when a cylindrical precast concrete member is set in a hard rock layer, and the construction process can be shortened. it can.

It is a whole side view of the cylindrical precast concrete member construction apparatus of the present invention. It is a top view of FIG. It is a top view of a pressure beam. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus. It is explanatory drawing of the construction process by this invention apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylindrical precast concrete member 11 Bottom part 12 Body 13 Lower end 14 Hammer grab bucket 21 Support pile 22 Top part 23 Base frame 24 Temporary receiving bracket 25 Ground anchor 31 Cylindrical precast concrete member segment 32,33,34,35,36,37, 38, 39 Arrow 40 Cylindrical precast concrete member pressure beam 41 Hydraulic jack 42 for press fitting 42 Lower end portion 44 Pressurizing portion 50 Diameter expansion rotary excavator 51 Casing pipe 52 Casing pipe (upper portion)
53 Casing pipe (addition part)
54 Cutter bit 55 Arrow 60 Full rotation driving part 61 Support hydraulic jack 70 Frame frame 71 Elevated beam 72, 73 Column 74 Extension span 80 Bogie 81 Rail 90 Travel device 100 Crane 101 Hard rock layer 102 Normal soil

Claims (2)

  When sinking a cylindrical precast concrete member in a hard formation, a cylindrical precast concrete member is suspended in a cylindrical precast concrete member via a casing pipe having an all-round rotation drive unit at the upper end through a casing pipe. Each time the cylindrical precast concrete member sinks by the depth of one segment, the casing pipe is cut off below the all-round rotation drive unit, and the tip of the cylindrical precast concrete member pressing jack is cut off from the base frame, and the separated casing A lateral movement of an integral block comprising a pipe, the all-round rotation drive unit and the cylindrical precast concrete member pressurizing beam, and attaching a waiting tubular precast concrete member segment to the cylindrical precast concrete member pressurizing beam; Casing pie And connecting the casing pipe and connecting the cylindrical precast concrete member to the cylindrical precast concrete member set position. A method for constructing a tubular precast concrete member, comprising connecting a reduction jack to a base frame and repeating the settlement of the tubular precast concrete member.   Expanded rotary excavator for rock excavation suspended down to the bottom bottom of the cylindrical precast concrete member via a casing pipe with an all-round rotation drive unit near the upper end, and the cylindrical precast concrete member segment from above the cylindrical precast concrete member A frame extending sideways up to the upper position of the standby position, a traveling device that supports the all-round rotation drive unit and the cylindrical precast concrete member pressure beam and travels horizontally on the frame, and is attached to the traveling device A lifting jack for raising and lowering the all-round rotation drive unit and the tubular precast concrete member pressurizing beam, and a tubular precast concrete member press-fitted to the base frame and attached to the tubular precast concrete member pressurizing beam. A cylindrical precast core characterized by having a jack Construction equipment of the cleat member.

Images