JP5503822B2 - Retaining wall and its construction method - Google Patents

Description

  The present invention relates to a retaining wall and a construction method thereof, and more particularly, to a retaining wall and a construction method thereof that can exhibit high stability and rigidity without a large footing.

  It is necessary to install a retaining wall to prevent the ground from collapsing on cliffs caused by cuts exceeding 2m in height, embankments exceeding 1m in height, or in grounds where height differences occur, such as steep slopes or waterways. Occurs. The retaining wall is made of a reinforced concrete structure or a wall made of precast concrete products or concrete blocks.

  Such retaining walls are usually designed with an overall L-shaped or inverted T-shaped cross section, and a relatively large foundation footing is formed at the bottom of the retaining wall. The foundation footing functions to ensure a wide contact area for transmitting the load acting on the retaining wall (earth pressure) and the weight of the retaining wall to the supporting ground and to prevent the retaining wall from falling.

  Since the foundation footing extends relatively large toward the high ground side, it is necessary to excavate the high ground extensively during the retaining wall construction and backfill the excavated portion after the retaining wall construction. However, extensive excavation and backfilling of high ground causes problems such as a great amount of excavation work, an increase in the amount of moving soil, and instability of backfill soil. In general, a large foundation footing is made of a concrete plate having a thickness of about 500 mm to 600 mm, and it is necessary to use a large amount of concrete and reinforcing bars in the construction. Furthermore, depending on the environment, conditions or topography of the construction site, it may be difficult to construct a large foundation footing.

  In order to solve such problems of foundation footing construction, the retaining wall structure of the dry construction method configured to give the bending moment on the non-falling side in advance to the steel main pile that constitutes the column is published in Patent No. 2824217 It is disclosed in the publication.

  In the retaining wall structure, the present inventor integrates the reinforced concrete structure standing column arranged directly above the pile and the underground beam-shaped foundation of the reinforced concrete structure that supports the vertical load of the wall body, and reinforced concrete. In Japanese Patent Application No. 2005-113760 (Japanese Patent Application Laid-Open No. 2006-291575), a retaining wall having a structure in which a buttress having a structure protrudes behind the retaining wall and a conical beam-shaped foundation is connected to the tip of the buttress. is suggesting.

  As described above, in the retaining wall having a reinforced concrete buttress and a weight-shaped foundation, the center of gravity of the retaining wall is displaced to the high ground side by the weight of the buttress and the weight-shaped foundation, and the frictional force between the buttress wall surface and the ground is The falling of the retaining wall can be effectively prevented by the frictional force between the spindle foundation and the ground.

  In addition, the present inventor proposed a retaining wall structure in which a reinforced concrete structure wall is supported by a steel pipe pile arranged at the wall core position of the retaining wall in Japanese Patent Application No. 2006-136071 (Japanese Patent Laid-Open No. 2007-308876). ing.

Publication No. 2824217 JP 2006-291575 A JP 2007-308876

  When the above retaining wall structure using buttress and spindle foundation or the above retaining wall structure using steel pipe pile is applied to a retaining wall less than 3m in height, construction of large foundation footing is omitted and excavation Although the intended purpose such as reduction of soil volume and reduction of construction work has been achieved, when such a structure is applied to a retaining wall with a height of 3 m or more, structural disadvantages and structural Special considerations were necessary, and problems such as construction difficulties, prolonged construction period, increased amount of excavated soil, increased amount of concrete and rebar, and increased construction costs were raised.

  The present invention has been made in view of such circumstances, and its purpose is to omit the construction of large foundation footings, ease of construction, shortening the construction period, reducing the amount of excavated soil, concrete An object of the present invention is to provide a retaining wall that can reduce the amount and the amount of reinforcing bars, reduce the construction cost, and can structurally stabilize a retaining wall having a height of 3 m or more, and a construction method thereof.

In order to achieve the above object, the present invention provides a reinforced concrete structure wall body, a reinforced concrete structure integrated with the wall body so as to give a stable moment against horizontal earth pressure to the wall body, and a pyramid shape in the form of an underground beam. In the retaining wall with the foundation,
Reinforced concrete that extends between the first and second steel pipe piles arranged in parallel to the high ground, the weight foundation and the wall body, and whose both ends are integrally joined to the weight foundation and the wall body With underground beams of structure,
The pile heads of the first and second steel pipe piles are arranged at a height position of 1/2 or more of the height of the wall body measured from a low ground surface,
The pile head of the first steel pipe pile is embedded in the wall body and integrated with the wall body, and is disposed at the intersection of the wall body and the underground beam,
The pile head of the second steel pipe pile is embedded in the spindle foundation and integrated with the spindle foundation, and is disposed at the intersection of the spindle foundation and the underground beam,
The underground beam has a beam main reinforcement fixed to the wall body and the concrete of the pyramid shape, and is integrated with the wall body so that its own weight acts on the wall body as the stable moment. And is integrally joined to the spindle base,
The weight-shaped foundation forms a second reinforced concrete structure beam having a beam reinforcing bar arranged in the axial direction of the foundation so that the weight of the weight-shaped foundation acts on the wall body as the stable moment. to provide a retaining wall which is characterized vinegar Rukoto.

The present invention is also a retaining wall construction method configured as described above, wherein the first and second steel pipe piles are constructed on a high ground,
An excavation process for excavating high ground to construct the concrete form of the spindle foundation, underground beam and wall body;
A formwork and bar arrangement process for constructing the concrete formwork and bar arrangement of the spindle foundation, underground beam and wall body;
Retaining wall comprising placing concrete in the formwork and having a space in the formwork and a concrete placing process for filling the first steel pipe pile and the second steel pipe pile with concrete. The construction method is provided.

  According to the above configuration of the present invention, the vertical load that displaces the center of gravity of the retaining wall to the non-falling side acts on the back of the wall body by the underground beam and the weight-shaped foundation, and the frictional force resists the falling of the retaining wall. Acts between the ground beam and the cone-shaped foundation and the ground. Therefore, according to the present invention, the conventional large foundation footing can be omitted, and the amount of excavated soil, the amount of concrete and the reinforcing bars can be reduced, the construction period can be shortened, and the construction cost can be reduced.

Further, according to the retaining wall structure, the underground beam constitutes a horizontal axis member that interconnects the pile heads of the steel pipe piles that constitute the vertical axis member, and is composed of the underground beam and the steel pipe pile. A structural structure is formed behind the wall. Since the pyramidal foundation interconnects the structures of the separated ramen structures, a three-dimensional square frame that structurally stabilizes the retaining wall having a height of 3 m or more is constructed behind the wall body. Moreover, since the steel pipe pile, the spindle foundation and the underground beam are constructed on the high ground without excavating the high ground largely, the construction is easy.

  In addition, a large number of steel pipe piles arranged in parallel stabilize the high ground, as well as fall or slide of the retaining wall, underground beams and weight foundations due to pile weight (self-weight), pulling resistance, friction with the ground, etc. This effectively prevents the lifting of rocks, so the spindle foundation is positioned at a relatively high position, that is, at a position where the excavation depth from the ground surface on the high ground side is shallow, reducing the amount of excavated soil and lowering construction costs. Etc. can be achieved.

  According to the retaining wall and the construction method of the present invention, the construction of large foundation footing is omitted, the construction is easy, the construction period is shortened, the amount of excavated soil is reduced, the amount of concrete and reinforcing bars are reduced, and the construction cost is low. In addition, the retaining wall having a height of 3 m or more can be structurally stabilized.

FIG. 1 is a perspective view showing a basic configuration of a retaining wall according to the present invention. FIG. 2 is a cross-sectional view showing the structure of the retaining wall of the present invention. FIG. 3 is a partial front view of the retaining wall on the low ground side. 4 is a cross-sectional view taken along the line II of FIG. 5 is a cross-sectional view taken along line II-II in FIG. FIG. 6 is a perspective view conceptually showing the shaft structure of the retaining wall. FIG. 7 is a longitudinal sectional view showing the topography of the ground where the retaining wall is to be constructed. FIG. 8 is a longitudinal sectional view showing the ground excavation range in the pile construction process. FIG. 9 is a longitudinal sectional view showing a state where the steel pipe pile is press-fitted into the ground. FIG. 10 is a plan view showing a state where the steel pipe pile is press-fitted into the ground. FIG. 11: is a longitudinal cross-sectional view which shows the formwork and bar arrangement process of a wall and an underground beam. FIG. 12: is a top view which shows the formwork and bar arrangement process of a wall and an underground beam. FIG. 13 is a longitudinal sectional view showing a state immediately after placing concrete. FIG. 14: is a longitudinal cross-sectional view which shows the state after performing concrete curing and formwork dismantling / removal.

DESCRIPTION OF SYMBOLS 1 Retaining wall 2, 3 Steel pipe pile 4 Wall body 5, 6 Underground beam 7 Concrete 8 Frame HG High ground Ha High ground surface LG Low ground La Low ground surface

  According to a preferred embodiment of the present invention, the height of the pile heads of the first and second steel pipe piles is arranged at a height position that is 2/3 or more of the height of the wall measured from the low ground surface. The wall body, the underground beam, and the pyramidal foundation are arranged in a lattice shape in plan view.

  Preferably, the internal hollow areas of the first and second steel pipe piles are filled with concrete that is continuous with the concrete of the weight foundation, the underground beam and the wall body.

  According to a further preferred embodiment of the present invention, the steel pipe pile is constructed on the high ground without excavating the high ground, and the excavation step includes a step of excavating the high ground to the height position of the pile head. As a modification, the pile process includes a process of excavating the high ground to the height position of the pile head before the construction of the steel pipe pile.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing a basic configuration of a retaining wall according to the present invention. FIG. 2 is a cross-sectional view showing the structure of the retaining wall of the present invention, and FIG. 3 is a partial front view of the retaining wall on the low ground side. 1 and 2, the wall core direction of the wall body is shown as the X direction, and the direction orthogonal to the wall core is shown as the Y direction.

  The retaining wall 1 is arranged according to the topography of the high ground HG so as to prevent the high ground HG from collapsing or collapsing toward the low ground LG. The retaining wall 1 is aligned in the X direction at a distance of e1 from the steel pipe pile 2 on the high ground side of the steel pipe pile 2 and arranged in the X direction (wall core direction) at a predetermined interval. Y-direction (direction perpendicular to the wall core) between the piles of the steel pipe piles 3, the wall 4 of the reinforced concrete structure extending in the X direction along the pile row of the steel pipe piles 2, and the pile heads of the steel pipe piles 2 and 3 ) And an underground beam 6 extending in the X direction along the pile row of the steel pipe pile 3, and an integral earth retaining wall that can withstand the earth pressure of the high ground HG. Configure. The height difference of the ground is 3 to 6 m, for example, about 5 m, and the distance h1 from the low ground surface La to the top end surface of the wall body 4 is substantially equal to the height difference of the ground and is about 5 m.

  The weight of the retaining wall 1 is that the supporting force of the ground ground of the wall body 4 and the underground beams 5 and 6, the frictional force between the steel pipe piles 2 and 3 and the ground, and further the It is supported by support force or the like. Horizontal loads such as earth pressure and seismic force acting on the retaining wall 1 are caused by friction forces acting between the wall 4 and the underground beams 5 and 6 and the ground, and the weight of the underground beams 5 and 6. It is supported by the stable moment of the wall 1 and the pulling strength of the steel pipe piles 2 and 3.

  The steel pipe pile 2 is arranged at the intersection of the wall body 4 and the underground beam 5, and the steel pipe pile 3 is arranged at the intersection of the underground beams 5 and 6. The steel pipe piles 2 and 3 and the underground beam 5 constitute a rigid frame structure formed by rigidly joining linear shaft members in a rectangular shape, and each of the shaft members (steel pipe piles 2 and 3 and the underground beam 5) by an external force. The bending moment generated in is transmitted to the ground or the like through each shaft member.

  4 and 5 are sectional views taken along lines I-I and II-II in FIG. 2, and FIG. 6 is a perspective view conceptually showing the shaft structure of the retaining wall.

  The steel pipe piles 2 and 3 are made of steel pipes having a uniform circular cross section, and are buried vertically in the ground. The lower end portions of the steel pipe piles 2 and 3 preferably reach the support layer S having an N value of 10 or more. The lower end openings of the steel pipe piles 2 and 3 are closed by the circular blind plates 21 and 31.

  The height levels of the upper end openings 22 and 32 of the steel pipe piles 2 and 3 are substantially the same, and are set at a position lower than the top end level of the wall body 4 by a predetermined distance h2. The height h4 (= h1-h2) of the upper end openings 22 and 32 measured from the low ground surface La is ½ or more of the height h1 of the top end surface of the wall body 4 measured from the low ground surface La, preferably The dimension is set to 2/3 or more. In this example, since h1 = 5 m, h4 ≧ 2.50 m and h2 ≦ 2.50 m are set, and preferably h4 ≧ 3.33 m and h2 ≦ 1.67 m.

  The top end positions of the underground beams 5 and 6 are substantially the same, and are set slightly above the positions of the upper end openings 22 and 32. The top end positions of the underground beams 5 and 6 are set to a position lower than the top end level of the wall body 4 by a predetermined distance h3.

  Preferably, the distance h2 is set in a range of 800 to 1600 mm, and the distance h3 is set in a range of 500 to 1200 mm. When a building B such as a wooden structure building is constructed in the vicinity of the retaining wall 1 as shown by an imaginary line (two-dot chain line) in FIG. 4, the distance h3 is the distance between the foundation of the building B and the underground beams 5 and 6. The dimension that can be constructed on the upper side, for example, at least about 700 mm is set. When the high ground HG in the vicinity of the retaining wall 1 is used as an open space, a green space, a paved road, etc., the distance h3 is a minimum dimension capable of maintaining the buried state of the underground beams 5 and 6, for example, 500 mm. Can be set to a degree. In this example, the distance h2 is set to 1300 mm, and the distance h3 is set to 1000 mm.

  As shown in FIG. 5, the internal hollow regions of the steel pipe piles 2 and 3 are filled with concrete that is continuous with the concrete of the wall body 4 and the underground beams 5 and 6. The diameters of the steel pipes constituting the steel pipe piles 2 and 3 are preferably set in the range of 100 mm to 400 mm. In consideration of the workability of concrete filling, it is desirable to set the diameter of the steel pipe to 200 mm or more. In this example, the diameter of the steel pipe is set to about 250 mm.

  The upper part of the steel pipe pile 2 is embedded in the wall body 4 at the wall core position of the wall body 4, the lower part of the steel pipe pile 2 penetrates into the ground, and the tip part (lower end part) of the steel pipe pile 2 is supported as described above. Reach layer S. The pile head (upper end) of the steel pipe pile 3 is buried in the center of the underground beam 6 and penetrates into the ground, and the front end (lower end) of the steel pipe pile 3 reaches the support layer S as described above.

  The wall body 4 is formed of a reinforced concrete structure wall body in which vertical and horizontal wall bars (not shown) are arranged. The wall thickness of the wall body 4 is preferably set in the range of 400 mm to 750 mm. In this example, the wall thickness of the wall body 4 is set to about 500 mm. As the wall bars, general-purpose deformed bars of about D10 to D25 are used, and the wall bars interval is set to a dimension of about 100 mm to 300 mm. In this example, a deformed reinforcing bar of D13 is used as the wall reinforcement, and the interval between the wall reinforcements is set to 250 mm.

  The underground beams 5 and 6 are made of horizontal horizontal members having a reinforced concrete structure and have a square cross section. The cross-sectional dimensions of the underground beams 5 and 6 are set to a square cross section or a rectangular cross section with dimensions of about 450 mm × 450 mm to 1000 mm × 1000 mm. In this example, the underground beams 5 and 6 have a square cross section of 600 mm × 600 mm. The underground beams 5 and 6 displace the gravity center position of the retaining wall 1 to the high ground HG side by its own weight. Due to the displacement of the position of the center of gravity of the retaining wall 1, a stable moment that acts to prevent the retaining wall 1 from falling is obtained.

  The main beam (not shown) of the underground beam 5 is arranged in the underground beam 5 in the axial direction of the underground beam 5. The end of the main beam of the underground beam 5 extends into the wall body 4 and the underground beam 6 and is fixed to the concrete of the wall body 4 and the underground beam 6. As a beam main reinforcing bar (not shown) of the underground beam 5, a general-purpose deformed reinforcing bar of about D16 to D29 can be preferably used. Moreover, as a stirrup bar (not shown) of the underground beam 5, a general-purpose deformed bar of about D13 to D19 can be preferably used. For example, the stirrup muscles are arranged at intervals of about 150 mm to 250 mm.

  The main beam (not shown) of the underground beam 6 is arranged in the underground beam 6 in the axial direction of the underground beam 6. As the beam main reinforcing bar, a general-purpose deformed reinforcing bar of D16 to D29 can be preferably used. Moreover, the general-purpose deformed reinforcing bar of about D13 to D19 can be preferably used as the stirrup bar (not shown) of the underground beam 6. For example, the stirrup muscles are arranged at intervals of about 150 mm to 250 mm.

  In this example, at least two upper bars (not shown) and at least two lower bars (not shown) are arranged on the underground beams 5 and 6 as beam main bars, D19 deformed bar is used as the lower bar. Moreover, in this example, the deformed reinforcing bar of D13 is arranged at intervals of 200 mm as the stirrup bars of the underground beams 5 and 6.

  FIG. 6 conceptually shows the frame structure that constitutes the retaining wall 1.

  The retaining wall 1 has a frame 8 having a rigid frame structure composed of steel pipe piles 2 and 3 and an underground beam 5. The frames 8 are arranged with a predetermined interval set to about 2 to 4 m apart from each other. Each frame 8 is interconnected by the wall body 4 and the underground beam 6, and the frame 8, the wall body 4 and the underground beam 6 constitute a three-dimensional structure as a whole.

  The dead weight of the underground beams 5 and 6 and the pulling resistance of the steel pipe pile 3 work as a stable moment against the falling moment of the retaining wall 1. The earth pressure of the high ground HG acting on the wall body 4 in the Y direction is supported by the reaction force of the frame 8 indicated by solid line arrows in FIG.

  When an external force (earthquake force or the like) in the direction opposite to the earth pressure of the high ground HG is applied to the wall body 4, the external force is supported by the reaction force of the frame 8 indicated by the broken-line arrows in FIG.

  Further, when an external force (seismic force or the like) acting in the X direction acts on the wall body 4, the external force is dispersed in the wall body 4 and the frame 8 and is supported by the reaction force of the wall body 4 and the frame 8.

  Next, the construction method of the retaining wall 1 will be described.

  FIG. 7 is a longitudinal sectional view showing the topography of the ground on which the retaining wall 1 is to be constructed. The height difference h5 of the ground is about 5 m, which is substantially the same as the height h1 (FIG. 1) of the retaining wall 1. The ground has a fairly steep slope (inclined face) Ga, and the slope angle of the slope Ga with respect to the ground faces La and Ha is 60 degrees to 90 degrees, for example, 70 degrees.

  FIG. 8 is a longitudinal sectional view showing a ground excavation range in the pile construction process, and FIGS. 9 and 10 are a longitudinal sectional view and a plan view showing a state in which the steel pipe piles 2 and 3 are press-fitted into the ground.

  The excavation range Hb of the high ground HG excavated for placing the steel pipe piles 2 and 3 is shown by broken lines in FIG. The excavation range Hb is limited to the minimum range in which the steel pipe piles 2 and 3 and the underground beams 5 and 6 can be constructed. That is, in the construction of the retaining wall 1, unlike the conventional retaining wall construction method, it is not necessary to excavate the high ground HG for a large footing construction.

  A pile hole (not shown) is drilled in the excavated ground surface Hc of the high ground HG by a pile driving machine or the like using an auger, and the steel pipe piles 2 and 3 are pressed into the ground. You may make it press-fit the steel pipe piles 2 and 3 to a ground with a pile driving machine, without drilling a pile hole. The steel pipe piles 2 and 3 are embedded in the ground up to a position where the tip portions having the circular blind plates 21 and 31 slightly bite into the support layer S. The pile heads (upper end openings 22 and 32) of the steel pipe piles 2 and 3 protrude slightly upward from the excavated ground surface Hc with the top surface opening opened, or at the same height level as the excavated ground surface Hc. To position. As the steel pipe piles 2 and 3, a rotary penetrating buried pile having a drilling blade (tip screw) at the tip may be used, and the steel pipe piles 2 and 3 may be constructed by a heavy machine such as a pile driver.

  If desired, the steel pipe piles 2 and 3 may be constructed before excavating the high ground HG. In this case, the pile heads of the steel pipe piles 2 and 3 are press-fitted into the ground by a jig of a pile driving machine slightly above the excavated ground surface Hc or to an equivalent level. The excavation range Hb is excavated by excavation work in a formwork and bar arrangement process described later.

  As a modification, the steel pipe piles 2 and 3 are constructed so that the pile heads of the steel pipe piles 2 and 3 protrude slightly upward from the ground surface Ha of the high ground HG or are located at the same level as the ground surface Ha. It is also possible. In this case, the excavation range Hb is excavated by excavation work in a formwork and bar arrangement process described later, and the portions of the steel pipe piles 2 and 3 positioned above the positions of the upper end openings 22 and 32 are cut and removed.

  FIG.11 and FIG.12 is the longitudinal cross-sectional view and top view which show the formwork and bar arrangement process of the wall body 4 and the underground beams 5 and 6. FIG.

  The high ground HG and the low ground LG are excavated for the construction of the wall body 4 and the underground beams 5 and 6. The high ground HG and the low ground LG are limited to the minimum range required for the construction of the wall body 4 and the underground beams 5 and 6. The ground contact portions of the wall body 4 and the underground beams 5 and 6 are leveled by abandoned concrete and quarrying, and the concrete placement forms 11, 51, and 61 of the wall body 4 and the underground beams 5 and 6 are in a predetermined position. Built. The wall bars of the wall body 4 and the underground beams 5 and 6, the beam main bars, and the stirrup bars (not shown) are arranged in the molds 11, 51 and 61. After completion of the bar arrangement and formwork, the flowing concrete C (FIG. 13) is poured into the formwork 11, 51, 61.

  FIG. 13 is a longitudinal sectional view showing a state immediately after placing concrete, and FIG. 14 is a longitudinal sectional view showing a state after performing concrete curing, formwork dismantling / removal, and excavated soil backfilling.

  As shown in FIG. 13, the concrete C is filled in the molds 11, 51, 61 and flows into the steel pipe piles 2, 3 via the upper end openings 22, 32 of the steel pipe piles 2, 3, A few internal hollow regions are filled. After a predetermined curing period, the molds 11, 51, 61 are disassembled and removed, and the excavated soil of the high ground HG and low ground LG is backfilled.

  FIG. 14 shows a state where the backfilling process of the high ground HG is completed. Since the low ground LG is only excavated in the minimum necessary range for the construction of the wall body 4, the low ground LG can be backfilled with a relatively small amount of backfill soil. The high ground HG is also only excavated to the minimum necessary for the construction of the steel pipe piles 2 and 3 and the underground beams 5 and 6, so the high ground HG is increased for large footing construction. Compared to the conventional retaining wall construction method for excavation, the high ground HG can be backfilled with a considerably small amount of backfill soil. That is, according to the retaining wall structure of the present invention, the amount of excavated soil, waste soil, and backfill soil can be greatly reduced.

  Although the construction of the retaining wall 1 is completed by such backfilling of excavated soil, according to the retaining wall 1 thus constructed, the underground beam 5 is formed of the steel pipe piles 2 and 3 constituting the vertical shaft member. It constitutes a horizontal frame member that interconnects the pile heads, and the underground beam 6 interconnects the structure of the ramen structure composed of the underground beam 5 and the steel pipe piles 2 and 3, so that a three-dimensional square frame is formed. It is built behind the wall 4.

  A vertical load that displaces the center of gravity of the retaining wall 1 to the non-falling side acts on the back of the wall body 4 by the dead weight of the underground beams 5 and 6, and a frictional force that resists the falling of the retaining wall 1 is applied to the underground beam. It acts between 5 and 6 and the high ground HG.

  In addition, the steel pipe pile 3 stabilizes the high ground HG and also causes the retaining wall 1 to fall or slide, and the underground beams 5 and 6 to rise due to pile weight (self-weight), pulling resistance, friction with the ground, and the like. Effectively prevent.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments, and various modifications or changes can be made within the scope of the present invention described in the claims. It goes without saying that it is possible.

  For example, the embodiment described above relates to a retaining wall having a straight wall body 4, but various planar forms such as a retaining wall having a curved planar shape or a retaining wall that is bent at an angle in a complicated manner. The present invention may be applied to the retaining wall.

  Moreover, in the said Example, although the pile row | line of the steel pipe pile 3 is arrange | positioned in parallel with the wall body 4, and the underground beam 5 is orientated in the direction orthogonal to the wall body 4, the pile row | line | column of the steel pipe pile 3 is used. The walls 4 may be arranged at a predetermined angle or irregularly, and the underground beam 5 may be oriented at a predetermined angle with the wall 4.

  Furthermore, in the said Example, although the steel pipe piles 2 and 3 of circular cross section are used, you may use the steel pipe of cross sections, such as a square, a polygon, an ellipse, and an oval, as the steel pipe piles 2 and 3.

  Furthermore, the cross-sectional shape of the underground beams 5 and 6 in the above embodiment can be arbitrarily set. For example, the underground beams 5 and 6 may be designed to have a cross-section other than the rectangular cross-section.

  In addition, you may arrange | position a drain hole etc. in an appropriate place in a retaining wall.

  The present invention is applied to a retaining wall constructed on a cliff, a steep slope, a water channel or the like. Since the retaining wall of the present invention does not require the construction of a large footing, the workability of the retaining wall is greatly improved. Further, according to the present invention, since the amount of excavation of the high ground can be reduced, it is possible to construct the retaining wall even in the ground where it has been difficult to construct the retaining wall with the conventional retaining wall structure. Furthermore, according to the present invention, the retaining wall having a height of 3 m or more can be structurally stabilized by the three-dimensional square frame constructed on the high ground side of the wall body, so the practical effect is remarkable. is there.

Claims (7)

In a retaining wall having a wall body of reinforced concrete structure and a reinforced concrete structure integrated with the wall body so as to give a stable moment against horizontal earth pressure to the wall body and a cone-shaped foundation in the form of an underground beam,
Reinforced concrete that extends between the first and second steel pipe piles arranged in parallel to the high ground, the weight foundation and the wall body, and whose both ends are integrally joined to the weight foundation and the wall body With underground beams of structure,
The pile heads of the first and second steel pipe piles are arranged at a height position of 1/2 or more of the height of the wall body measured from a low ground surface,
The pile head of the first steel pipe pile is embedded in the wall body and integrated with the wall body, and is disposed at the intersection of the wall body and the underground beam,
The pile head of the second steel pipe pile is embedded in the spindle foundation and integrated with the spindle foundation, and is disposed at the intersection of the spindle foundation and the underground beam,
The underground beam has a beam main reinforcement fixed to the wall body and the concrete of the pyramid shape, and is integrated with the wall body so that its own weight acts on the wall body as the stable moment. And is integrally joined to the spindle base,
The weight-shaped foundation forms a second reinforced concrete structure beam having a beam reinforcing bar arranged in the axial direction of the foundation so that the weight of the weight-shaped foundation acts on the wall body as the stable moment. retaining wall, wherein to Rukoto.   The height of the pile heads of the first and second steel pipe piles is arranged at a height position that is 2/3 or more of the height of the wall body measured from a low ground surface. Retaining wall as described in.   3. The retaining wall according to claim 1, wherein the wall body, the underground beam, and the weight-shaped foundation are arranged in a lattice shape in a plan view.   The interior hollow region of the first and second steel pipe piles is filled with concrete that is continuous with the concrete of the weight foundation, underground beam, and wall body. Retaining wall as described in paragraph. It is the construction method of the retaining wall described in any one of Claims 1 thru | or 4, Comprising:
A pile process for constructing the first and second steel pipe piles on a high ground;
An excavation process for excavating high ground to construct the concrete form of the spindle foundation, underground beam and wall body;
A formwork and bar arrangement process for constructing the concrete formwork and bar arrangement of the spindle foundation, underground beam and wall body;
Retaining wall comprising placing concrete in the formwork and having a space in the formwork and a concrete placing process for filling the first steel pipe pile and the second steel pipe pile with concrete. Construction method.   The construction method according to claim 5, wherein the pile step includes a step of excavating a high ground to a height position of the pile head before construction of the steel pipe pile.   6. The steel pipe pile is constructed on a high ground without excavating the high ground, and the excavation step includes a step of excavating the high ground to a height position of the pile head. Construction method.

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