JP6298688B2 - Embankment - Google Patents

Description

  The present invention relates to an embankment suitable for building a breakwater, a tide embankment, or raising an existing embankment that is provided on a coast or a riverbank and prevents water disasters caused by tsunamis, floods, and the like.

  Since Japan is located on the course of typhoons, typhoons hit every year, causing flooding due to river flooding. Also, in the Great East Japan Earthquake that occurred on March 11, 2011, the dyke broke down due to an unexpected large tsunami, and seawater crossed the levee, causing unexpected catastrophic damage. Even the constructed ones were found to be inadequate with existing breakwaters such as breakwaters and seawalls.

  For this reason, the construction of a dike that assumes a large tsunami is an urgent issue, and the existing dike is being raised or a new dike is being developed. Some newly developed dikes are due to precast walls and concrete frames.

  For example, Patent Document 1 discloses a precast wall body. This includes “a steel pipe pile, a footing supported by the steel pipe pile, and a wall body through hole that is disposed above the footing and penetrates in the in-plane direction. A precast wall body having a wall sheath and a pipe, wherein the footing has a footing through hole penetrating in a thickness direction, and an inner surface of the footing through hole is provided with a footing sheath. The footing sheath extends to a position above the upper surface of the footing, the steel pipe pile is inserted into the footing sheath, the footing sheath is inserted into the wall sheath of the precast wall, There is described “a dam body characterized in that a grout material is filled in a gap between the footing sheath and the pipe and the steel pipe pile inserted into the footing sheath”.

  Moreover, as a thing by a concrete frame, there exists patent document 2, for example. Here, “a footing is constructed at the upper end of a steel pipe pile that has penetrated into the ground, and a steel plate panel is placed on the surface of the concrete frame that constitutes the dam body in a tide embankment in which a levee body is erected on the footing. There is described a “sea levee characterized in that the steel plate panel and the concrete frame are integrally joined to each other”.

  Moreover, there exists patent document 3 as a thing regarding the raising of the embankment, for example. Here, "in the uplift bank for raising the existing levee installed in various water areas such as rivers and coasts, has an opening in the direction of the existing dam with a substantially U-shaped cross section, and the upper end of the existing levee A flat plate connecting body forming a hollow portion therebetween, a positioning portion that protrudes inside the flat plate connecting body, abuts on an upper end portion of the existing lantern and determines a vertical position with respect to the existing lantern, and There is described "raised levee characterized by comprising fixing members for fixing both side plates to upper both side walls of the existing levee".

  On the other hand, during the reconstruction of the earthquake disaster, there have been calls for shortage of concrete supply to the coast, lack of manpower (insufficiency of skilled workers), large parts due to road conditions, difficulty in transporting heavy parts on land, and increased transportation costs. These also need to be taken into account when raising an existing levee or constructing a new levee.

Japanese Patent No. 5024489 JP 2013-234449 A JP 2006-45814 A

  The present invention has been made in view of the background and problems as described above, and is strong and high-quality capable of dealing with large tsunamis, and can be used for land transportation of materials and members. The purpose of the present invention is to provide a levee body that does not require a skilled worker, is easy, reduces the amount of cast-in-place concrete, and suppresses the amount of concrete used at the construction site as much as possible.

  The dam body according to claim 1 of the present application is “a dam body in which precast hard walls are arranged on the foundation portion in the continuum direction to form a wall surface, and the foundation portion includes steel pipe piles arranged in two rows. A steel / concrete composite footing supported by the steel pipe pile and arranged in parallel with a predetermined interval in the bank body continuous direction, and a steel / concrete composite joint disposed between the steel / concrete composite footings, The above-mentioned precast hard wall erected on the concrete composite footing is a dam body characterized in that it is provided at a central portion in the direction perpendicular to the wall surface of the steel / concrete composite footing.

  The levee body of the present invention is roughly divided into a base portion and a precast hard wall that forms the wall surface of the dam body, and these are mainly units manufactured in a factory. The units are assembled after being transported to the construction site, and the bank is constructed by arranging the precast hard walls on the foundation in the bank body continuous direction.

  Each unit is manufactured at the factory, so it is stable and of high quality. In addition, the work at the construction site can be built without relying on the skills and intuition of skilled workers because these units are simply assembled according to the work manual or cast in place in part.

  The foundation includes a steel pipe pile, a steel / concrete composite footing, and a steel / concrete composite connection. Steel pipe piles are conventionally used for pile construction, and are arranged in two rows at predetermined intervals in the bank body continuous direction (wall surface direction of the bank body).

  The steel-concrete composite footing is supported by two of each row of steel pipe piles arranged in two rows, and at a predetermined interval according to the interval in the dam body continuous direction of these steel pipe piles, It is arranged side by side in the continuous direction of the embankment on the steel pipe pile.

  This steel / concrete composite footing consists mainly of a unit (footing unit) made of a steel box frame manufactured at a factory, and is a hybrid type of steel / concrete composite structure in which the footing unit is covered with concrete. belongs to. By adopting such a hybrid type, a solid foundation can be obtained by simple construction, and construction by cast-in-place concrete can be reduced to reduce the amount of concrete used at the construction site as much as possible.

  The steel box frame is formed in a box shape using a steel material such as a steel plate or H-shaped steel, and has a length in a direction perpendicular to the juxtaposed direction (bank body continuous direction) when installed at a construction site. Long vertical ones. The width of the box frame (length in the juxtaposed direction) is larger than the pile head diameter of the steel pipe pile.

  The dimensions of the steel box frame are generally about 1 to 2 m in height, 1.5 to 2.5 m in width, and about 5 to 10 m in length, but are appropriately determined depending on load conditions.

  Moreover, this steel box frame is divided into a plurality of sections in the longitudinal direction having a long length, and a section for connecting to the steel pipe pile and a section for connecting to the precast hard wall are provided. By partitioning in this way, it is possible to make a strong footing unit, and by reducing the amount of concrete used by making the section without a role hollow, the weight of the footing unit can be reduced.

  Similar to the steel / concrete composite footing, the steel / concrete composite joint is mainly composed of a unit (joint unit) made of a steel box frame manufactured in a factory, and the joint unit is covered with concrete. It is a hybrid type of steel / concrete composite structure.

  This steel / concrete composite joint is responsible for the load acting on the precast rigid wall and plays the role of transmitting the load to the steel / concrete composite footing. Between steel and concrete composite footings. The connection between the steel / concrete composite joint and the steel / concrete composite footing is, for example, by joining with a joint using a high-strength bolt or a tensile joint, or by joining concrete using a perforated steel plate and a reinforcing bar. Done.

  The steel box frame of the joining unit is also a box-like frame made of a steel material such as a steel plate or H-shaped steel. The size of the box frame is determined based on the size of the footing unit and the distance between adjacent footing units, and the height of the steel / concrete composite joint is the same as the height of the steel / concrete composite footing.

  The precast hard wall standing on the steel / concrete composite footing and the steel / concrete composite joint and forming the wall surface of the levee body is made of a reinforced concrete precast member.

  The type of concrete is not particularly limited. Usually, it is ordinary concrete, but high-strength concrete, heavy-weight concrete using heavy aggregates, polymer concrete, acid-resistant concrete, sulfate-resistant concrete, etc. that take into account corrosion and deterioration due to seawater salt can also be used.

  The precast hard wall is composed of a wall surface portion and a foundation connecting portion below the wall surface portion. The surface of the wall surface portion is usually a surface perpendicular to the steel / concrete composite footing or the steel / concrete composite connection portion, but is not necessarily limited thereto, and may have a curved surface.

  Moreover, in order to reinforce a wall surface, you may stick a steel plate on the surface of a wall surface part, or may paste energy absorption materials, such as a cushioning material. In order to improve durability, it can also be coated with a salt barrier coating. From the viewpoint of landscape and aesthetics, letters, patterns and colors can be applied to the walls and greened.

  A female joint member (for example, a joint pipe) in a mechanical joint system is pre-installed in the foundation connecting portion in the precast hard wall, and the steel / concrete composite footing or steel / Connected with concrete composite connection.

  As described above, the precast hard wall is erected on the steel / concrete composite footing and the steel / concrete composite joint, but the precast hard wall erected on the steel / concrete composite footing is steel / concrete composite. The steel / concrete composite footing is provided at the center in the direction perpendicular to the wall surface so that the vertical cross section of the footing and the precast hard wall is an inverted T shape.

  As mentioned above, the precast hard wall is not limited to a straight wall, but may be a curved wall or a combination of a straight wall and a curved wall. It means all of those that are erected at the center in the direction perpendicular to the wall surface.

  Thus, by making the connection structure of the steel / concrete composite footing and the precast hard wall into an inverted T shape, for example, an effect of being able to cope with either a tsunami wave or a wave wave is obtained.

  The dimensions of the precast hard wall are not particularly limited, but considering land transportation by truck, it is preferable that the length (height) is 15 m or less and the weight is 25 t or less.

  The embankment according to claim 2 of the present application is “the steel / concrete composite footing uses a footing unit made of a box frame formed of H-shaped steel, and the periphery of the footing unit is covered with concrete. The levee body according to claim 1, wherein

  As described above, in the present invention, the steel / concrete composite footing is mainly a unit (footing unit) made of a steel box frame manufactured at a factory, and the steel obtained by covering the footing unit with concrete.・ A hybrid type of concrete composite structure.

  The steel box frame is made of a steel material such as a steel plate or H-shaped steel, but is preferably made of H-shaped steel. By using the H-shaped steel, there are merits that the steel weight of the steel material is reduced, the steel material processing is easy, the member connection is easy on the site, and the connection reinforcing bar to the precast hard wall is easily fixed.

  The embankment according to claim 3 of the present application is “the steel / concrete composite connecting portion uses a connecting unit made of a box frame formed of H-shaped steel, and the periphery of the connecting unit is made of concrete. The levee according to claim 1 or 2, characterized in that it is covered.

  As described above, in the present invention, the steel / concrete composite connecting portion is mainly composed of a unit (joining unit) made of a steel box frame manufactured in a factory, like the steel / concrete composite footing, It is a hybrid type of steel / concrete composite structure in which the joining unit is covered with concrete.

  Therefore, as with the above footing unit, the use of H-section steel has the advantages of reducing the steel weight of the steel material, facilitating steel material processing, facilitating member connection on site, and facilitating fixing of the connecting rebar to the precast hard wall. It is preferable to form a box frame using H-shaped steel.

The bank body according to claim 4 of the present application is “the footing unit is divided into five in the length direction, and this section includes a section in the center of the footing unit on which the precast hard wall is erected, Two compartments provided with insertion holes for inserting the upper ends of the steel pipe piles in each row arranged symmetrically with respect to the compartments in two rows, and the compartments in the middle portion and the compartments The levee body according to claim 2 , characterized in that it comprises two hollow sections provided between the two.

  In the present invention, in the height direction, the steel / concrete composite footing is installed between the steel pipe pile and the precast hard wall, and each of the steel pipe pile and the precast hard wall is connected to the footing unit.

  If the footing unit is composed of one box frame, it is difficult to connect the steel pipe pile or the precast hard wall. If the box frame is divided into a plurality of sections, the connecting work between the footing unit and the steel pipe pile and the connecting work between the footing unit and the precast hard wall can be performed separately, so that the construction work of the levee body is facilitated. In addition, the amount of concrete used can be reduced or the weight can be reduced to facilitate transportation on land.

  The partitioning structure of the footing unit is not particularly limited, but the central part of the footing unit where the precast hard wall is erected and the two rows arranged symmetrically with respect to the partition and arranged in two rows It is divided into five sections: two sections provided with an insertion hole for inserting the upper end of the steel pipe pile, and two hollow sections provided between these sections and the center section. Is preferred.

  By connecting the precast hard wall at the central section of the footing unit, an inverted T-shaped structure of the steel / concrete composite footing and the precast hard wall can be easily obtained.

  The connection between the steel pipe piles and the footing units in each row in the steel pipe piles arranged in two rows is performed using the outer sections of the footing unit, and the upper ends (pile heads) of the steel pipe piles are respectively placed in the sections. This is preferably done by inserting and hardening with concrete. Therefore, it is preferable that an insertion hole is provided in the outer sections so that the upper end of the steel pipe pile can be inserted.

  It is preferable to keep the space between these outer compartments and the central compartment because they do not have a role of connection with other members as described above. Even if there is a hollow portion, there is no problem in strength and durability if a box frame is formed with a steel material having high rigidity such as H-shaped steel and a portion requiring coating is covered with concrete. By providing the hollow portion (hollow section), the amount of concrete used can be reduced, the weight of the footing unit can be reduced, and transportation on land is facilitated.

  The “hollow” means that a hardened cement body such as mortar or concrete does not exist, and includes not only a space but also a case where earth and sand, a lightweight filler, an energy absorbing material or the like is filled.

  The dam body according to claim 5 of the present application is characterized in that “the precast hard wall is made of reinforced concrete, and is composed of a wall surface portion and a foundation connecting portion below the wall surface portion and thicker than the wall surface portion. The levee body according to any one of claims 1 to 4.

  As mentioned above, the precast hard wall is mainly reinforced concrete, and contributes to the connection between the wall part forming the wall surface of the dam body and the steel / concrete composite footing and steel / concrete composite connection part below it. It consists of what was integrally formed with the base connection part.

  These wall sections and foundation connection sections are not strictly separated, but the thickness of the foundation connection section is made thicker than the wall section, and the wall section is erected on the foundation platform like a tombstone. It is preferable to adopt a form. The maximum thickness of the foundation connecting portion is preferably 1.5 to 3.0 times the maximum thickness of the wall surface portion.

  By adopting such a configuration, the precast hard wall can be stably erected and the connection with the foundation can be strengthened.

  According to claim 6 of the present application, “the wall width of the precast hard wall in the continuous direction of the bank body is larger than the width of the steel / concrete composite footing, and the precast hard wall is adjacent to the steel / concrete composite footing. The levee body according to any one of claims 1 to 5, wherein the levee body is installed across the steel / concrete composite connecting portion.

  As mentioned above, the precast hard wall is alternately erected on the steel / concrete composite footing and the steel / concrete composite joint to form the wall surface of the levee body. The steel / concrete composite footings and the steel / concrete composite joints are made to match the width of the steel / concrete composite joints in the continuous direction of the dam body, and one precast hard wall is placed on one steel / concrete composite footing. The wall surface of the levee body is constructed so that one precast hard wall stands on each other.

  However, it is not limited to such a dam body structure. For example, the wall width of the precast hard wall in the continuous direction of the dam body is made larger than the width of the steel / concrete composite footing, and the precast hard wall is made of steel / concrete composite footing. It is also possible to make a dike structure standing upright across the steel-concrete composite connecting part. The wall width of the precast hard wall is, for example, a length obtained by adding half of the width of the steel / concrete composite joint to the width of the steel / concrete composite footing.

  As mentioned above, by adopting a dam body structure where the precast hard wall is erected across the steel-concrete composite joint adjacent to the steel-concrete composite footing, it can be used in steel pipe piles arranged in two rows It is possible to obtain an effect that the load can be directly distributed to the longitudinal steel box frame material across the pair of steel pipe piles to be distributed and the load burden can be distributed.

  The levee body of the present invention is mainly composed of a plurality of units manufactured at a factory, and these units are assembled and constructed at the construction site, so that they are stable and of high quality and require on-site construction requiring skilled workers. It becomes easy.

  In addition to the above-mentioned high quality, the foundation is made of a steel / concrete composite member, so that it can be a strong dam body that can cope with a large tsunami.

  In addition, by adopting a hybrid steel / concrete structure mainly composed of steel box frame units, the use of cast-in-place concrete is reduced to minimize the amount of concrete used at the construction site. A bank can be obtained and the current problems such as a shortage of concrete supply to the construction site that occurred during the earthquake reconstruction can be solved.

  Furthermore, if the dimensions of the unit assembled at the construction site are adjusted, transportation to coastal areas where road conditions are not good is possible.

It is a perspective view which shows one Embodiment of the bank body of this invention. (A) is the figure seen from the front side (waterside side), (b) is the figure seen from the back side (land side). It is the figure which showed more easily the structure of the bank of the said invention described in FIG. (A) is a front view, (b) is a plan view, and (c) is a side view. It is a perspective view which shows the steel and concrete composite footing using the footing unit which can be used suitably for construction of the foundation part of the dam body of this invention, and the steel and concrete composite connection part using a joining unit. (A) is a diagram of a footing unit, (b) is a diagram of a steel / concrete composite footing, (c) is a diagram of a joint unit connected to a steel / concrete composite footing, and (d) is a steel / concrete composite footing and steel / concrete It is a connection figure with a concrete composite connection part. It is a perspective view which shows the precast hard wall in the bank body of this invention. The construction process of the foundation is shown. (A) is the steel pipe pile construction process, (b) is the footing unit installation process, (c) is the joining unit installation process, (d) is the foundation completion process, and (e) is completed. The basic part is shown. The process from the completion of the foundation to the completion of the dam body of the present invention by standing a precast hard wall on the foundation is shown. (F) shows the process of standing the precast hard wall, and (g) shows the completion process of the dam body and the road by backfilling the soil. It is a figure which shows an example of the connection method of a precast rigid wall and a foundation part, and is a longitudinal cross-sectional enlarged view of the foundation connection part in a precast rigid wall.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments described below.

  FIG. 1 is a perspective view showing an embodiment of a bank body 1 of the present invention. (A) is the figure seen from the front side (waterside side), (b) is the figure seen from the back side (land side).

  In this example, the bank body 1 of the present invention is constructed on an existing bank 2. The levee body 1 includes a base portion 3 and a precast hard wall 4 that forms the wall surface of the dam body 1, and the wall surface is formed on the base portion 3 by arranging the precast hard walls 4 in the levee body continuous direction.

  The foundation 3 includes a steel pipe pile 5, a steel / concrete composite footing 6, and a steel / concrete connection portion 7. The steel pipe piles 5 are arranged in two rows in the bank body continuous direction at a predetermined interval. In addition, the steel / concrete composite footing 6 is supported by two of each row of the steel pipe piles 5 arranged in two rows, and is determined in accordance with the interval of the steel pipe piles 5 in the bank body continuous direction. Are arranged in parallel in the bank body continuous direction above the steel pipe pile 5.

  Further, a steel / concrete composite connecting portion 7 is provided under the precast hard wall 4 between adjacent steel / concrete composite footings 6 and 6, and the foundation portion on the steel pipe pile 5 in the foundation portion 3 is a dam body. The steel / concrete composite footing 6 and the steel / concrete composite connection portion 7 are alternately laid in the continuous direction.

  On the other hand, the precast hard wall 4 is made of reinforced concrete having a shape as shown in the figure, and as shown in the figure, is erected on the steel / concrete composite footing 6 and the steel / concrete composite connection portion 7 and arranged in the continuous direction of the levee body. The wall surface of the levee body 1 is formed.

  In this example, the wall width of the precast rigid wall 4 in the bank body continuous direction is ½ of the total width in the bank body continuous direction of the steel / concrete composite footing 6 and the steel / concrete composite joint 7. The precast hard wall 4 is installed across the steel / concrete composite joint 7 adjacent to the steel / concrete composite footing 6. By installing in this way, load is distributed directly to the steel box frame material in the longitudinal direction across the corresponding pair of steel pipe piles in the steel pipe piles arranged in two rows, and the load burden is distributed The effect that can be achieved is obtained.

  In the present invention, as shown in the figure, the precast hard wall 4 is provided at the center of the steel / concrete composite footing 6 in the direction perpendicular to the wall surface, and the vertical cross section of the steel / concrete composite footing 6 and the precast hard wall 4 is inverted T. Form a mold. As described above, by making the connecting structure of the steel / concrete composite footing 6 and the precast hard wall 4 into an inverted T shape, for example, an effect of being able to cope with both a tsunami wave and a wave wave is obtained. In this example, the back side (land side) of the levee body 1 of the present invention is used daily as the road 8.

  FIG. 2 is a view showing the structure of the bank body 1 of the present invention described in FIG. 1 in an easy-to-understand manner. (A) is a front view, (b) is a plan view, and (c) is a side view.

  As shown in FIG. 2A, the bank body 1 of the present invention is roughly composed of a base portion 3 and a precast hard wall 4. The foundation portion 3 includes a steel pipe pile 5, a steel / concrete composite footing 6, and a steel / concrete composite connection portion 7.

  Below the steel / concrete composite footing 6 is a steel pipe pile 5, and the steel / concrete composite footing 6 is supported by the steel pipe pile 5 in such a manner that the pile head of the steel pipe pile 5 enters the steel / concrete composite footing 6. Yes. There is no steel pipe pile below the steel / concrete composite connecting portion 7 provided in such a manner that the steel / concrete composite footings 6 and 6 are connected to each other.

  The precast hard wall 4 is erected on the steel / concrete composite footing 6 and the steel / concrete composite connection portion 7 so that the wall surface is formed in the bank body continuous direction. As shown in the figure, the precast hard wall 4 is provided so as to straddle the steel / concrete composite footing 6 and the steel / concrete composite joint 7.

  As shown in FIGS. 2 (b) and 2 (c), the steel pipe piles 5 are provided in two rows substantially in parallel at predetermined intervals of about 250 to 450 cm in the bank body continuous direction. One row is a row of waterside steel pipe piles, and the other row is a row of inland side steel pipe piles. The distance between these two rows is about 150 to 600 cm.

  On the steel pipe pile 5, a steel / concrete composite footing 6 is provided at a predetermined interval in accordance with the interval of the steel pipe pile 5 as shown in the figure.

  The steel / concrete composite footing 6 is preferably formed by covering a footing unit made of a steel box frame with concrete 9. In this example, the footing unit is divided into three parts, and the pile heads of the steel pipe piles 5 are inserted into and connected to the outer side parts 11 and 11, and each steel / concrete composite footing 6 has two steel pipe piles. 5 and 5 are supported. A precast hard wall 4 is erected above the central section 10.

  The dimensions of the steel / concrete composite footing 6 are roughly the dimensions of the dimensions of the footing unit plus the concrete coating thickness.

  As can be seen from FIG. 2 (c), the dam body 1 of the present invention has a structure in which the vertical cross section is an inverted T-shape with the precast hard wall 4 and the steel / concrete composite footing 6. By making the connecting structure of the steel / concrete composite footing and the precast hard wall into an inverted T shape, for example, an effect of being able to cope with both a tsunami wave and a wave wave is obtained.

  A steel / concrete composite connecting portion 7 is provided between the adjacent steel / concrete composite footings 6 and 6 provided at predetermined intervals in the bank body continuous direction so as to connect them.

  The steel / concrete composite connecting portion 7 is also preferably formed by covering a joining unit made of a steel box frame with concrete 9 like the steel / concrete composite footing 6.

  As shown in FIG. 2 (a), the dimensions of the steel / concrete composite connecting portion 7 are the same as those of the steel / concrete composite footing 6, and the lateral width (width in the bank body continuous direction) is substantially adjacent to the above. The distance between the steel / concrete composite footings 6 and 6.

  The vertical width (width in the direction perpendicular to the bank body continuous direction) is not particularly limited, but is preferably as short as possible as long as the precast rigid wall 4 can be firmly erected. Usually, it is about 1/4 to 1/3 of the vertical width of the steel / concrete composite unit 6 (length in a direction perpendicular to the bank body continuous direction).

  As described above, in the levee body 1 of the present invention, the steel pipe pile 5 and the steel / concrete composite footing 6 are connected and the adjacent steel / concrete composite footings 6 and 6 are connected by the steel / concrete composite connection portion 7. As a result, the steel pipe pile 5, the steel / concrete composite footing 6 and the steel / concrete composite connecting portion 7 are integrated to form a solid foundation 3.

  FIG. 3 shows a steel / concrete composite footing 6 using a footing unit 12 and a steel / concrete composite connection part 7 using a joining unit 13 that can be suitably used for the construction of the foundation 3 of the dam body 1 of the present invention. FIG. (A) is a view of the footing unit 12, (b) is a view of the steel / concrete composite footing 6, (c) is a view of the joining unit 13 connected to the steel / concrete composite footing 6, and (d) is a steel / concrete composite footing. FIG. 3 is a connection diagram of the footing 6 and the steel / concrete composite connection portion 7.

  As shown in FIG. 3A, the footing unit 12 is composed of a vertically long steel box frame. In this example, the box frame is formed using the H-shaped steel 15, but the present invention is not limited to this. Use of an H-shaped steel is preferable because a strong box frame can be easily formed at a low price. A headed stud 16 is provided on the surface of the H-shaped steel 15 to improve adhesion to the concrete. Further, as shown in the figure, connecting reinforcing bars 26 are provided vertically at predetermined intervals in the short direction of the footing unit 12 in the central section. The method of attaching the H-shaped steel 15 to the surface is, for example, a method of fixing the H-shaped steel to the H-shaped steel with a nut for screw rebar.

  As shown in the figure, in this example, the box frame is divided into five sections, ie, sections 14 and 14 between a central section 10 and outer sections 11 and 11. The number of sections is not limited to this, and may be three sections as described above, for example. By partitioning into a plurality of compartments, a hollow portion can be created, so that there is an advantage that the steel / concrete composite footing 6 can be reduced in weight.

  As shown in FIG. 3 (b), a part of the footing unit 12 is covered with concrete 9 (covered concrete) to form a steel / concrete composite footing 6. The coating thickness is not particularly limited, but a sufficient cover is taken in consideration of corrosion due to salt damage. This production takes place in the factory. By manufacturing in the factory, stable and high quality products can be obtained and on-site construction can be simplified.

  An insertion hole 17 for inserting a pile head of a steel pipe pile into the steel / concrete composite footing 6 is provided at the lower portion of the outer section 11, and the upper portion is opened to fill the concrete. The space 14 between them is hollow in what is covered with the concrete 9. By making it hollow, the amount of concrete used can be reduced and the weight of the steel / concrete composite footing 6 can be reduced.

  As shown in FIG.3 (c), the joining unit 13 also consists of steel box frames. In this example, like the footing unit 12, the H-shaped steel 15 is used. A headed stud 16 for improving adhesion to the concrete is also provided on the surface of the H-shaped steel 15. Further, a connecting reinforcing bar 26 is also provided on the upper surface of the joining unit 13 as shown in the figure.

  As shown in the figure, connection ends 18 for connecting to the steel / concrete composite footing 6 (footing unit 12) are provided at the four corners of the joining unit 13, and a high strength bolt 19 is formed in the form shown in the figure. Thus, the joining unit 13 is connected to the steel / concrete composite footing 6 (footing unit 12). This connection may be made at the construction site, but it is preferable to make the shape shown in FIG. By doing it at the factory, it is easy to connect reliably and the work at the construction site can be simplified.

  The steel / concrete composite footing 6 and the joining unit 13 are transported to the site in a connected or non-connected form. At this time, the steel / concrete composite footing 6 is placed on the two steel pipe piles 5 and 5, and as shown in FIG. 11 and 11 are installed in the form inserted respectively.

  FIG. 3 (d) is a completed view of the foundation unit 20 constituting the foundation part 3 in which a pair of steel pipe piles 5, 5, one steel / concrete composite footing 6 and one steel / concrete composite connection part 7 are integrated. is there.

  The foundation part 3 in the levee body 1 of the present invention is constructed in such a form that the foundation single bodies 20 are connected and arranged in the levee body continuous direction. If such a foundation is constructed, the construction is simple and the amount of on-site concrete used can be suppressed.

  As shown in FIG. 3 (c), the basic unit 20 composed of one steel / concrete composite footing 6 and one steel / concrete composite joint 7 has the steel / concrete composite footing 6 and the joining unit 13 as shown in FIG. After installation, as shown in FIG. 3 (d), the uncovered portion of the footing unit 12 is covered with the cast-in-place concrete 21 except for some of the connection end portions 18 and the connection reinforcing bars 26, and the opening portion is filled. 13 is obtained by coating.

  At the same time, the steel / concrete composite connecting portion 7 is also completed. As shown in the drawing, a connecting reinforcing bar 26 for connecting to the precast hard wall protrudes from the upper surface of the central portion of the steel / concrete composite footing 6 and the upper surface of the steel / concrete composite connection portion 7.

  In the present invention, the concrete coating of the footing unit 12 is thus made by partial coating with concrete 9 at the factory and the remaining coating with the cast-in-place concrete 21 at the construction site, and the concrete coating of the joining unit 13 is done by cast-in-place concrete. This is done by covering with 21.

  FIG. 4 is a perspective view showing the precast hard wall 4 in the bank body 1 of the present invention. Here, a state where two precast hard walls 4 are connected is shown.

  As shown in the drawing, the precast hard wall 4 forming the wall surface of the dam body 1 of the present invention is made of reinforced concrete 24, and is made up of a wall surface portion 22 and a foundation connecting portion 23 below the wall surface portion 22.

  The wall surface portion 22 is a portion that literally becomes the wall surface of the levee body 1. In this example, the wall surface portion 22 is a flat plate having a confrontation, but is not limited thereto, and may take various forms such as a curved shape, a surface with irregularities, and a pattern. Can do. In order to make the wall surface durable and strong, a reinforcing plate such as a steel plate or an FRC plate or a cushion material that absorbs wave energy may be attached to the surface of the wall surface portion 22.

  The dimension of the wall surface part 22 is appropriately determined by reinforced concrete cross-section calculation according to the load strength such as water pressure.

  The foundation connecting part 23 forms a part of the wall surface and serves as a base for stably standing the precast hard wall 4 and a connecting part between the steel / concrete composite footing 6 and the steel / concrete composite connecting part 7.

  Therefore, as shown in the figure, the base connecting portion 23 is preferably thicker than the wall surface portion 22. This thickness is preferably about 1.5 to 3.0 times that of the wall surface portion 22. Here, a taper 25 is provided on the upper portion of the base connecting portion 23. By providing the taper 25, smooth load transmission can be achieved, and compared with the case where a right-angle step is provided, there is an advantage that an important base portion is less likely to be broken due to a collision during a tsunami.

  FIGS. 5-6 is a perspective view which shows the construction example of the bank body 1 of this invention shown in FIG.

  FIG. 5 shows the construction process of the foundation 3. (A) shows the construction process of the steel pipe pile 5, (b) shows the installation process of the footing unit 12, (c) shows the installation process of the joining unit 13, (d) shows the completion process of the foundation part 3, (e ) Shows the completed foundation 3.

  First, in the existing levee 2, as shown in FIG. 5 (a), pile construction by the steel pipe piles 5 is performed and arranged in two rows at a predetermined interval. The pile head of the steel pipe pile 5 which becomes a connection part with the steel / concrete composite footing 6 is put on the ground about 100 cm. In the pile, a bottom plate is provided at a depth of about 200 cm from the top of the pile, and the cast-in-place concrete is filled into the pile at the top of the pile. If necessary, a pile stopper (steel plate) is installed on the pile head by field welding (not shown). After driving the steel pipe pile 5, the height is adjusted by cutting the pile head or the like in some cases.

  Next, as shown in FIG. 5 (b), a pair of steel / concrete composite footing 6 units (2 pieces), each of which is a concrete-covered part of a footing unit made of a steel box frame manufactured at a factory. The pile heads of the steel pipe piles 5 and 5 are installed at a predetermined interval in accordance with the interval between the steel pipe piles in the bank body continuous direction so that the pile heads enter the steel / concrete composite footing 6.

  Next, as shown in FIG.5 (c), the joining unit 13 which consists of a steel box frame manufactured at the factory is arrange | positioned between the steel and concrete composite footings 6 and 6, and it connects with these footings (footing unit). The connection is made with high strength bolts.

  In this example, the steel / concrete composite footing 6 and the joining unit 13 are separately manufactured at the factory, transported to the construction site, and connected at the construction site. As shown in FIG. Alternatively, a connecting unit in which the steel / concrete composite footing 6 and the joining unit 13 are connected at the factory may be carried to the construction site, and the adjacent steel / concrete composite footing 6 and one side of the joining unit 13 may be connected at the construction site. In this way, the connection work at the construction site can be simplified.

  Next, as shown in FIGS. 5 (d) and 5 (e), all the uncovered portions of the concrete where the steel material is exposed, except for the upper part of the connecting rebar 26 connected to the precast hard wall, are cast in place. Cover with 21. The coating thickness is the same as the coating thickness of the concrete 9 described above. In this way, the foundation 3 of the levee body 1 of the present invention is completed on the existing levee 2.

  FIG. 6 shows the process from the completion of the foundation 3 to the completion of the dam body 1 of the present invention by standing the precast hard wall 4 on the foundation 3. (F) shows the standing process of the precast hard wall 4, and (g) shows the completion process of the dam body 1 and the road 8 by the backfilled soil 31.

  As shown in FIG. 6 (f), the precast hard wall 4 is formed on the steel / concrete composite footing 6 and the steel / concrete composite joint 7 in the completed foundation so that a wall surface is formed in the continuous direction of the levee body. Standing up and lining up. The steel / concrete composite footing 6 is erected at the center of the precast rigid wall 4 and the steel / concrete composite footing 6 so that the longitudinal section (side surface) is an inverted T-shape. Adjacent precast hard walls 4 and 4 are connected to each other by, for example, sandwiching a sealing material for the purpose of water stop and tightening it with a tensile force of a steel rod.

  Thereafter, as shown in FIG. 6 (g), the embankment 1 of the present invention is completed by filling the space between the steel / concrete composite footings 6, 6 protruding by the backfilling soil 31. The form of backfilling with the soil 31 for backfilling is not necessarily limited to the form shown in the figure, and for example, it may be embanked in such a manner as to cover the lower base connecting portion of the precast hard wall 4. The backfill soil 31 is not limited to mere soil and sand but may be a mixture of cement or other solidifying material.

  The back side (land side) of the precast hard wall 4 can be used as the road 8. In that case, it may be constructed according to a conventional road construction method such as laying a roadbed material in the lower layer.

  FIG. 7 is a view showing an example of a method for connecting the precast hard wall and the foundation portion, and is an enlarged vertical cross-sectional view of the foundation connection portion 23 in the precast hard wall 4.

  As shown in the figure, a mortar-filled joint pipe 28 is provided at the lower end of a reinforced concrete reinforcing bar 27 arranged in a foundation connecting portion 23 in a precast hard wall 4 made of reinforced concrete 24. The pipe 28 of this mortar filling type joint has a length that allows the connecting reinforcing bars 26 to be inserted firmly and an inner diameter that can absorb a slight construction error in the reinforcing bar diameter. Also, a mortar inlet 29 and a mortar outlet 30 are provided in a form connected to the pipe so that mortar can be injected and filled into the pipe 28 of the mortar filling type joint.

  As shown in FIG. 5 (d), the precast hard wall 4 and the foundation portion 3 are connected by connecting the steel / concrete composite footing 6 and the connecting rebar 26 projecting upward from the steel / concrete composite joint 7. 4 is inserted into the pipe 28 of the mortar-filled joint, and the periphery of the connecting reinforcing bars 26 is solidified with mortar injected and filled into the pipe. The mortar is preferably a high strength mortar. In order to strengthen the connection, the connecting reinforcing bars 26 may be deformed reinforcing bars. In this example, there are two connection locations, but the present invention is not limited to this, and connection may be performed at three or more locations.

  As described above, the dike body of the present invention is manufactured by manufacturing several precast members (units) at a factory and assembling and constructing them at a construction site. Construction on site is easy without the need for skilled workers.

  In addition, the foundation is strong because it is a hybrid type of steel / concrete composite structure mainly composed of steel box frame units, and it reduces the amount of concrete used at the construction site as much as possible by reducing the amount of cast-in-place concrete. This can solve the recent problems such as the shortage of concrete supply to the construction site that occurred during the earthquake reconstruction.

DESCRIPTION OF SYMBOLS 1 ... Dam body, 2 ... Existing levee, 3 ... Foundation part, 4 ... Precast hard wall, 5 ... Steel pipe pile, 6 ... Steel-concrete composite footing, 7 ... Steel-concrete composite connection part, 8 ... Road, 9 ... Concrete, DESCRIPTION OF SYMBOLS 10 ... Section of center part, 11 ... Outer section, 12 ... Footing unit, 13 ... Joining unit, 14 ... Between section, 15 ... H-section steel, 16 ... Headed stud, 17 ... Insertion hole,
18 ... Connection end, 19 ... High strength bolt, 20 ... Single foundation, 21 ... In-situ concrete,
DESCRIPTION OF SYMBOLS 22 ... Wall part, 23 ... Foundation connection part, 24 ... Reinforced concrete, 25 ... Taper, 26 ... Connection reinforcement, 27 ... Reinforcement of reinforced concrete, 28 ... Pipe of mortar filling type joint, 29 ... Mortar injection port, 30 ... Mortar discharge port 31 ... Soil for backfilling

Claims (6)

  A dam body in which precast hard walls are arranged on a foundation portion in a wall continuation direction to form a wall surface, and the foundation portion is supported by two rows of steel pipe piles and supported by the steel pipe pile in a levee body continuation direction. The precast that is erected on the steel / concrete composite footing, comprising a steel / concrete composite footing arranged side by side and a steel / concrete composite joint disposed between the steel / concrete composite footings. An embankment characterized in that the hard wall is provided at a central portion of the steel / concrete composite footing in a direction perpendicular to the wall surface.   The steel / concrete composite footing uses a footing unit made of a box frame formed of H-shaped steel, and the surrounding of the footing unit is covered with concrete. The embankment described in 1.   The steel / concrete composite connecting portion uses a joining unit composed of a box frame formed of H-shaped steel, and the periphery of the joining unit is covered with concrete. The bank body according to 1 or 2. The footing unit is divided into five sections in the length direction, and these sections are provided on the outer sides symmetrically with respect to the section in the center of the footing unit where the precast hard wall is erected. Two compartments provided with insertion holes for inserting the upper ends of the steel pipe piles in each row arranged in two rows, and two hollow compartments provided between these compartments and the central compartment The levee body according to claim 2 , comprising:   The precast hard wall is made of reinforced concrete, and includes a wall surface portion and a foundation connecting portion below the wall surface portion and thicker than the wall surface portion. The listed embankment.   The wall width of the precast hard wall in the levee body continuous direction is larger than the width of the steel / concrete composite footing, and the precast hard wall straddles the steel / concrete composite joint adjacent to the steel / concrete composite footing. The bank body according to any one of claims 1 to 5, wherein the bank body is installed.