JP6202680B2 - How to close the joint between caisson - Google Patents

Description

  The present invention relates to a method for closing a joint portion between an existing caisson and a caisson.

  The breakwater is installed by arranging a plurality of caissons on the foundation mound constructed on the bottom of the water. FIG. 1 shows a schematic view of a conventional breakwater (the caisson superstructure is not shown in FIG. 1). After the foundation mound M is constructed by the foundation rubble on the bottom of the water, a plurality of caissons 90 are installed on the foundation mound M. The breakwater main body is composed of a predetermined number of caissons 90 and a superstructure constructed on the caissons 90.

JP 09-143958 A

  In the case where a large tsunami hits the breakwater, and the breakwater is overturned and the breakwater function is lost, it is thought that the following progress is made until the breakwater / caisson falls. Referring to FIG. 1, when the tsunami flow hits the breakwater from the offshore side in the direction a, the tsunami flows over the breakwater caisson 90 in the direction b and overflows, and the rear mound region M1 indicated by a broken line In addition, a strong jet flow is ejected from the joint portion 91 between the caisson 90 and the caisson 90, and the jet flow in the direction c scours the back mound region M1. The overflow in the direction b and the jet flow in the direction c due to the tsunami causes the foundation mound to be scattered in the back mound region M1, and the foundation mound M is weakened. Then, the foundation mound M collapses due to the next tsunami or the subsequent pulling wave, and the breakwater main body composed of the caisson 90 and the superstructure thereon is overturned.

  As one of the countermeasures against the breakwater rollover at the time of the large tsunami attack as described above, it is conceivable to block the joint portion 91 between the caissons 90 and 90 to prevent the jet flow from being ejected from the joint portion 91.

  Patent Document 1 discloses a method of vertically drilling a through-hole penetrating from the top to the bottom of the caisson at both ends of the grout filling range as a method for closing the joint of the existing caisson. And inserting the grout material into the through-hole and filling the grout material into the cylindrical bag prior to filling the grout material into the adjacent caisson joints, It is proposed to form cylindrical stoppers at both ends of the filling range.

  However, in this closing method, after forming cylindrical stoppers at both ends of the filling range of the grout material, the joint gap between the stoppers is sprayed with high-pressure water through the injection pipe to wash the joint gap, and then, Since the Tremy tube is inserted into the joint gap and filled with the grout material and the joint gap is closed with the grout material, the process becomes complicated, time-consuming, and the construction time becomes long.

  An object of this invention is to provide the method of obstruct | occluding the joint part between the existing caissons by a simple method in view of the problem of the prior art as mentioned above.

The method for closing the joint portion between the caissons to achieve the above object is a method for closing the joint portion between the existing caisson and the caisson,
A first step of vertically building an injection outer tube with an inflatable bag body covered on the outer surface in the joint portion;
A second step of building an injection tube in the injection outer tube;
A pair of stretchable bag-like portions provided above and below the injection tube are inflated in the injection outer tube with water supplied from the injection tube, so that at least a part of the vertical space in the injection tube becomes a closed space. A third step to perform,
The filler supplied from the injection tube is filled between the outer surface of the injection outer tube and the bag body portion through the hole provided in the closed space and the injection outer tube, and the bag body portion is expanded. A fourth step of closing at least a part of the longitudinal space of the joint portion by forming a filler between the joint portion and the outer injection tube,
After depressurizing the bag-like portion after the fourth step, the injection tube is moved vertically in the outer injection tube, and the joint portion is moved vertically by repeating the third step and the fourth step. It is characterized by occlusion.

  According to this method of closing the joint between the caissons, the outer injection tube is built in the joint, the injection tube is installed in the injection outer tube, and the pair of upper and lower bag-like portions of the injection tube are inflated with water to inject the inner tube. The space in the vertical direction is closed, and the filler is filled between the outer surface of the injection outer tube and the bag body portion through the hole of the closed space / injection outer tube and the bag body portion is expanded by filling the filler body. Is formed, the vertical space of the joint portion is closed, and then the filling tube is moved in the vertical direction and the same filling is repeated to form a filling body in the entire vertical direction of the joint portion between the existing caissons. The joint portion can be closed over the entire length by the filler. Thus, it is possible to close the joint filled with water by building the injection outer tube only once, the construction time is short, and the joint construction of the joint can be performed by a simple process. it can.

  In the method for closing the joint portion between the caissons, it is preferable that a through hole penetrating from the superstructure of the caisson to the joint portion is formed, and the injection outer tube is built into the joint portion from the through hole. Even if a superstructure is installed in the caisson, it can be handled by forming a through hole. In addition, this through-hole is filled with a filler after filling the joint part with the filler.

  Moreover, it is preferable to form a hole from the bottom of the joint part of the caisson into the foundation mound, and to insert the injection outer pipe to the hole when the outer pipe is built in the joint part. This improves the stability of the outer injection tube built in the joint.

  Moreover, it is preferable that the said injection | pouring pipe | tube has a 2 type | system | group structure which can supply the said bag-shaped part and can supply the said filling body. Thereby, water and a filling body can be supplied at a required time with a single injection tube.

  Moreover, it is preferable that the said injection | pouring outer tube | pipe is comprised from a some short tube, and covers the said bag body part for every said short tube, and is sealed.

  In addition, after filling the bag body with the filler in the entire longitudinal direction of the joint, the injection tube is pulled out, the injection outer tube is filled with the filler, and the injection outer tube remains in the joint. It is preferable to make it. As a result, it is not necessary to pull out the outer injection tube, and the jointed state of the joint portion by the filler can be reliably maintained.

  Moreover, it is preferable to perform the filling with the filler at a plurality of locations separated in the horizontal direction in the joint between the caissons. Thereby, since the joint part of one place can be obstruct | occluded with a filler in multiple places, obstruction | occlusion of a joint part becomes certain.

  Further, as the filler, it is preferable to use a cement-based solidified material that expands after filling, such as cement bentonite, or a cement-based solidified material that does not shrink after filling, such as a non-shrinkable mortar.

  According to the method for closing a caisson joint of the present invention, the joint between existing caissons can be closed by a simple method.

It is the schematic of the conventional breakwater. It is a schematic top view of the breakwater which provided the filling body in the joint part between the existing caisson and caisson by this embodiment. FIG. 3 is a schematic cross-sectional view of a breakwater as seen by cutting along the line III-III in FIG. 2. It is the schematic sectional side view which looked at the breakwater of FIG. 2 from the side surface. It is a longitudinal cross-sectional view which shows the principal part of the injection tube which can be used for the sealing method of the joint part between caisons by this embodiment, and the injection | pouring outer tube, The state (a) which inserted the injection tube into the injection | pouring outer tube, In a state (b) where the packer portion of the injection tube is expanded, a state (c) where the bag body portion on the outer surface of the injection outer tube is expanded with a filler, and a cross-sectional view (d) of the injection outer tube is there. It is the external view (b) of the injection tube of FIG. 5, and sectional drawing (b) seen by cutting along the BB line. It is an external view which shows an example of the injection outer tube | pipe of FIG. It is a flowchart for demonstrating process S01-S11 which obstruct | occludes the joint part 91 between caisson 90 and 90 by this embodiment. FIG. 9 is a cross-sectional view (a) to (d) similar to FIG. 3, showing joint portions between caissons and the vicinity thereof for explaining steps S01 to S04 in FIG. 8. FIG. 10 is a cross-sectional view (a) to (d) similar to FIG. 9 for explaining steps S05 to S10 in FIG. 8.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 2 is a schematic top view of a breakwater provided with a filler at the joint between the existing caisson and the caisson according to the present embodiment. FIG. 3 is a schematic cross-sectional view of the breakwater as seen along the line III-III in FIG. 4 is a schematic cross-sectional side view of the breakwater of FIG. 2 as viewed from the side.

  As shown in FIGS. 2 to 4, the existing breakwater is constructed by arranging a plurality of caissons 90 on a foundation mound M made of rubble, and the joint 91 between the caissons 90 and 90 has a gap of about 10 to 30 cm. However, in this embodiment, the joint portion 91 is closed by disposing a plurality of cylindrical fillers 10 in the joint portion 91 between the caissons 90 and 90. As shown in FIG. 4, root blocks 95 are arranged before and after the foundation mound M.

  As shown in FIG. 3, an upper work 92 is provided at the upper part of the breakwater, and the upper work 92 is drilled for construction of the filler 10 at a position corresponding to the joint portion 91. Fillers 40 such as non-shrink mortar are filled in the holes.

  Next, the outer injection pipe and the injection pipe used in the step of installing the cylindrical filler 10 in the joint portion 91 between the caissons 90, 90 of the breakwater shown in FIGS. This will be described with reference to FIG. FIG. 5 is a cross-sectional view showing the main parts of the injection tube and the injection outer tube that can be used in the method for closing the joint portion between the caissons according to the present embodiment, and shows a state in which the injection tube is inserted into the injection outer tube (a). ), (B) showing a state where the packer portion of the injection tube is expanded in the injection outer tube, (c) showing a state where the bag body portion is expanded with the filler on the outer surface of the injection outer tube, and It is a transverse cross section (d) of a pipe. 6 is an external view (b) of the injection tube of FIG. 5 and a cross-sectional view (b) cut along the line BB.

  As shown in FIGS. 5 (a) and 5 (d), the injection outer tube 11 is composed of a cylindrical tube made of steel, and the outer surface thereof is covered with a tough cloth or a rubber material-based inflatable bag body 12 in a single layer. It has been. The bag body portion 12 is fixed and sealed to the outer peripheral surface 14 of the injection outer tube 11 by upper and lower sealing portions 15. The sealing part 15 can be comprised from a well-known band-shaped clamp and / or an adhesive agent. A large number of injection holes 13 are formed in the outer peripheral surface 14 of the injection outer tube 11, and the filler supplied inside is injected and filled between the outer peripheral surface 14 and the bag body portion 12 through the injection holes 13. It has become.

  As shown in FIGS. 6 (a) and 6 (b), the injection pipe 21 includes a two-system injection hose pipe 22 including a water supply pipe 22a and a filler supply pipe 22b for supplying water and a filler, respectively, and a holding portion. An elastic bag-like packer portion 23 made of a rubber material and held by 23a, an elastic bag-like packer portion 24 made of a rubber material and held by a holding portion 24a, and a pair of packer portions 23, 24 And a discharge hole 26 provided in the middle of the connection pipe 25 for discharging the filler. By making the injection hose pipe 22 into a two-system structure, water and a filler can be supplied at a necessary time with a single injection pipe 21.

  The injection tube 21 can be a double packer type special sleeve tube used in a chemical solution injection method for ground improvement. Such a double packer type special sleeve tube is proposed in, for example, Japanese Patent No. 3102786.

  Water is supplied to the packer portion 23 through the water supply pipe 22a of the injection hose pipe 22 shown in FIGS. 6 (a) and 6 (b) with the injection pipe 21 inserted into the injection outer pipe 11 as shown in FIG. 5 (a). Further, by supplying to the lower packer part 24 through the connecting pipe 25, the upper and lower packer parts 23, 24 are expanded as shown in FIG. 5B, and the packer parts 23, 24 are connected to the inner periphery of the injection outer pipe 11. By pressing the surface, a closed space 20 is formed in a part of the vertical direction in the injection outer tube 11.

  Next, in the state where the closed space 20 is formed in the injection outer tube 11 by the upper and lower packer portions 23 and 24 of FIG. 5B, the filler is supplied to the injection hose tube 22 of FIGS. 6A and 6B. The filler supplied through the tube 22b is discharged from the discharge hole 26 to the closed space 20 in the injection outer tube 11, and further through the numerous injection holes 13 in the outer peripheral surface 14 of the injection outer tube 11, the outer peripheral surface 14 and the bag body portion 12. Between and injected. As a result, as shown in FIG. 5C, the bag body portion 12 is expanded by filling the filler, and the filling body 30 is formed inside the bag body portion 12. By performing the expansion of the bag body portion 12 in the joint portion, the joint portion can be closed by the filling body 30 formed in the bag body portion 12. Thus, the bag part 12 changes from an inflatable part to an inflatable part by filling with a filler.

  The outer injection tube 11 can be configured to have a predetermined length corresponding to the height of the caisson by combining a plurality of short tubes. FIG. 7 shows an example of the injection outer tube shown in FIG. 5. The injection outer tube 11 includes, from above, an upper end portion 11 a corresponding to the upper work 92 of FIG. 3, and an injection outer tube 11 b-consisting of a plurality of short tubes. 11e, a lower end portion 11f located in the basic mound M of FIG. 3, and a tip end portion 11g screwed into the tip of the lower end portion 11f are connected to each other.

  The short injection outer tubes 11b to 11e are connected by a male screw 16a and a female screw 16b. For example, the upper injection outer tube 11b and / or the lower injection outer tube 11e are preliminarily provided in a plurality of types having different lengths. Prepared so that the entire length of the outer injection tube 11 can be adjusted. Moreover, the outer peripheral surface of each injection | pouring outer tube | pipe 11b-11e of a short tube is covered with the bag body part 12 of Fig.5 (a)-(c), and is fixed and sealed as mentioned above.

  Next, the cylindrical filler 10 is installed in the joint 91 between the caissons 90, 90 of the breakwater shown in FIGS. The process of closing the above will be described with reference to FIGS.

  FIG. 8 is a flowchart for explaining steps S01 to S11 for closing the joint portion 91 between the caissons 90, 90 according to the present embodiment. FIG. 9 is a cross-sectional view (a) to (d) similar to FIG. 3 showing the joint portion between caisson and the vicinity thereof for explaining steps S01 to S04 in FIG. 10 is a cross-sectional view (a) to (d) similar to FIG. 9 for explaining steps S05 to S10 in FIG. 9 and 10 are illustrated with slightly different scales for convenience of explanation.

  First, as shown in FIG. 9A, the drilling machine DM is installed on the superstructure 92 of the caisson 90 (S01). The drilling machine DM is installed at the position of the joint portion 91 of the caisson 90, and the casing CS is set for drilling. The drilling machine DM may be either a crawler type or a skid type, but is selected according to the actual situation at the site.

  Next, as shown in FIG. 9 (b), the upper work 92 is drilled while the casing CS is joined by the drilling machine DM, a through hole 92a is formed in the upper work 92, and the bottom of the joint portion 91 is drilled. Then, a hole M2 is formed in the basic mound M (S02).

  In the joint portion 91, since the interval between the caissons 90, 90 is usually about 10 to 30 cm, no drilling is necessary. The depth of the hole M2 is about 100 cm from the upper surface of the basic mound M. Further, as shown in FIG. 2, drilling is performed a plurality of times as many as the number of the fillers 10 provided at one joint portion 91. Thus, even if the superstructure 92 is installed in the caisson 90, it can be dealt with by forming the through hole 92a.

  Next, as shown in FIG. 9 (c), the injection outer tube 11 of FIG. 7 is inserted into the casing CS of the hole drilling machine DM (S03). Next, as shown in FIG. 9D, the casing CS of the hole drilling machine DM is pulled out (S04).

  As described above, as shown in FIG. 10A, the injection outer tube 11 is installed in the through hole 92a and the joint portion 91 of the upper work 92, and the erection of the injection outer tube 11 is completed. The joint portion 91 is filled with seawater. 7, the portion 11a is located in the through hole 92a of the upper work 92, the outer portions 11b to 11e made of a plurality of short tubes are located in the joint portion 91, and the portion 11f is the foundation. Located in hole M2 in mound M. Since the injection | pouring outer tube | pipe 11 has reached the bottom part of the hole M2, the front-end | tip part 11g can ensure stability.

  Next, as shown in FIG. 5A described above, the injection tube 21 is inserted and installed in the outer injection tube 11 built in the joint portion 91 of FIG. 10A (S05). The injection tube 21 is positioned so that the packer portions 23 and 24 correspond to the upper and lower ends of the outer injection tube 11e shown in FIG.

  Next, water is supplied to the packer portions 23 and 24 from the water supply pipe 22a of the injection hose pipe 22 of the injection pipe 21 of FIGS. 6 (a) and 6 (b), and the expanded upper and lower sides as shown in FIG. The closed space 20 is formed in the outer injection tube 11e by the packer portions 23 and 24 (S06).

  Next, the filler is discharged from the filler supply pipe 22b of the injection hose pipe 22 shown in FIGS. 6 (a) and 6 (b) into the closed space 20, and the outside of the injection as shown in FIGS. 5 (c) and 10 (b). By filling the space between the outer peripheral surface 14 of the tube 11e and the bag body portion 12, the bag body portion 12 expands due to the filling of the filler, and the filling body 30 is formed between the joint portion 91 and the injection outer tube 11. Then, the filler 30 closes the joint portion 91 within the longitudinal range of the injection outer tube 11e (S07).

  As the filler, it is preferable to use, for example, cement bentonite that expands slightly after filling, or non-shrink mortar that does not shrink after filling.

  Next, if the whole of the joint portion 91 is not yet filled (S08), the inside of the packer portions 23 and 24 of the injection tube 21 is decompressed and loosened, and the injection tube 21 is moved upward as shown in FIG. (S09). The injection tube 21 is positioned so that the packer portions 23 and 24 correspond to the upper end and the lower end of the injection outer tube 11d in FIG.

  Next, returning to the steps S06 and S07, as shown in FIG. 10C, the filler is similarly filled, and the filler 30 closes the joint portion 91 within the longitudinal range of the injection outer tube 11d.

  By repeating the steps S06 to S09 as described above, the filler 30 closes the joint portion 91 within the longitudinal range of the outer injection pipes 11c and 11b as shown in FIG. The cylindrical filler 10 composed of the filler 30 is formed, and the entire longitudinal direction of the joint portion 91 is closed by the filler 10 (S08).

  Next, after pulling out the injection tube 21, as shown in FIG. 10 (d), a filler 40 such as non-shrink mortar is filled in the inside of the injection outer tube 11 and in the through hole 92a of the upper work 92 (S10). .

  As described above, the cylindrical filler 10 and the filler 40 can be formed at one place in the longitudinal direction of the joint portion 91 between the caissons 90 and 90, and the joint portion 91 can be closed over the entire longitudinal direction. When further filling is performed at a position adjacent to the direction (S11), the process returns to step S03 and the same process is repeated.

  As described above, a plurality of cylindrical fillers 10 can be arranged in the joint portion 91 between the caissons 90 of FIG. 2 and FIG. 3, and the filler 40 can be arranged in the through hole 92a of the upper work 92. The joint portion 91 can be closed over the entire longitudinal direction as shown in FIGS.

  As described above, according to the method for closing the joint portion between the caissons according to the present embodiment, the joint portion 91 filled with water can be blocked over the entire longitudinal direction only by installing the injection outer tube 11 once. The construction time can be shortened, and the joint construction of the joint portion 91 can be performed by a simple process. Moreover, since the joint part 91 of one place can be obstruct | occluded with the filling body 10 in the several places distant from the horizontal direction, obstruction | occlusion of the joint part 91 is ensured.

  In addition, the filling body 10 is formed in the joint portion 91 and then the filling material is filled in the injection outer tube 11, and the injection outer tube 11 is left in the joint portion 91, so that the injection outer tube 11 does not need to be pulled out. In addition, the closed state of the joint portion 91 by the filler 10 can be reliably maintained.

  As described above, the modes for carrying out the present invention have been described. However, the present invention is not limited to these, and various modifications can be made within the scope of the technical idea of the present invention. For example, in FIGS. 9 and 10, the lower end portion 11 f of the outer injection tube 11 is configured as an injection outer tube, and the filling body 30 is formed in the hole M <b> 2 in the foundation mound M as well as the joint portion 91. Good.

  In FIG. 2, the five fillers 10 are formed at one joint portion 91, but the present invention is not limited to this, and the number of fillers 10 can be appropriately changed according to the caisson dimensions and the like. Of course.

  Further, in FIG. 10, one filler 10 is composed of four individual fillers 30, but the present invention is not limited to this, and can be appropriately changed according to the height of the caisson, Depending on the length of each filling body 30, the length and number of each injection outer tube (short tube) are set.

  Moreover, the space | interval of the packer parts 23 and 24 of the injection tube 21 of FIG. 5, FIG. 6 can be suitably changed according to the length of each injection | pouring outer tube | pipe (short tube). In addition, although the injection hose tube 22 of the injection tube 21 has a parallel structure of two tubes, it is not limited to this and may have a double tube structure.

  According to the present invention, in order to prevent the jet flow from being ejected from the joint part between the caissons, which is one of the measures against the breakup of the breakwater at the time of the great tsunami, it is easy to close the joint part between the existing caissons. The method can be implemented and the construction time is short.

DESCRIPTION OF SYMBOLS 10 Cylindrical filling body 11 Injection | pouring outer tube | pipe 11b-11e Injection | pouring outer tube | pipe 11g which consists of a short tube Tip part 12 Bag body part 13 Injection hole 14 Outer peripheral surface 15 of injection | pouring outer tube | pipe Sealing part 20 22a Water supply pipe 22b Filler supply pipe 23, 24 Packer part (bag-like part)
26 Discharge hole 30 Filling body 90 Caisson 91 Joint part 92 Upper work 92a Through hole M Basic mound

Claims (8)

A method of closing a joint between an existing caisson and a caisson,
A first step of vertically building an injection outer tube with an inflatable bag body covered on the outer surface in the joint portion;
A second step of building an injection tube in the injection outer tube;
A pair of stretchable bag-like portions provided above and below the injection tube are inflated in the injection outer tube with water supplied from the injection tube, so that at least a part of the vertical space in the injection tube becomes a closed space. A third step to perform,
The filler supplied from the injection tube is filled between the outer surface of the injection outer tube and the bag body portion through the hole provided in the closed space and the injection outer tube, and the bag body portion is expanded. A fourth step of closing at least a part of the longitudinal space of the joint portion by forming a filler between the joint portion and the outer injection tube,
After depressurizing the bag-like portion after the fourth step, the injection tube is moved vertically in the outer injection tube, and the joint portion is moved vertically by repeating the third step and the fourth step. A method for closing a joint between caissons, characterized by closing.   The method for closing a joint portion between caissons according to claim 1, wherein a through-hole penetrating from the superstructure of the caisson to the joint portion is formed, and the injection outer pipe is built into the joint portion from the through-hole.   The block of the joint part between the caissons according to claim 1 or 2, wherein a hole is formed in the foundation mound from the bottom part of the joint part of the caisson, and the hole is inserted to the hole when the injection outer pipe is built in the joint part. Method.   The said injection | pouring pipe | tube can supply the water to the said bag-shaped part, and has the 2 system | strain structure which can supply the said filling body, The obstruction | occlusion of the joint part between caisson of any one of Claim 1 thru | or 3 Method.   The said injection | pouring outer tube | pipe is comprised from the some short tube, The sealing method of the joint part between caissons of any one of Claim 1 thru | or 4 which covers and seals the said bag part for every said short tube.   After filling the bag body with the filler throughout the longitudinal direction of the joint, the injection tube is pulled out, the injection outer tube is filled with the filler, and the injection outer tube remains in the joint. Item 6. The method for closing a joint portion between caissons according to any one of Items 1 to 5.   The method for closing a joint portion between caissons according to any one of claims 1 to 6, wherein filling with the filler is performed at a plurality of locations separated in a horizontal direction in the joint portion between the caissons.   The method for closing a joint portion between caissons according to any one of claims 1 to 7, wherein a cement-based solidifying material that expands after filling or a cement-based solidified material that does not shrink after filling is used as the filler.

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