JP6870905B2 - Artificial ground and its construction method - Google Patents

Description

The present invention relates to artificial ground such as a horizontal pier type quay and a crossing bridge adopting a pier type structure, and a construction method thereof.

Generally, the above-mentioned artificial ground is constructed by connecting a beam member and a floor plate (superstructure) to a plurality of erected pile members, but in the conventional method of constructing an artificial ground, a plurality of erected pile members are used. After erection of the support work, the artificial ground was constructed by assembling the formwork and reinforcing bars and casting concrete on site.

However, in the conventional method of constructing artificial ground, work is required under severe working environment such as assembling support work at sea and assembling formwork and reinforcing bars. In addition, depending on the tide level, work between tides is required, and not only continuous work cannot be performed, but in some cases, there is a possibility of damage such as support work due to waves and outflow of formwork. Moreover, since there is a shortage of skilled workers who perform such work, it is necessary to standardize the work process when constructing superstructures (reduce special work that requires skill). ..

As a technique for solving the above-mentioned problems of the conventional artificial ground construction method, there is a technique of adopting a precast member when constructing a superstructure. For example, while inserting the pile heads of a plurality of pile members into a plurality of support holes provided in the precast member, the precast member is installed so as to cover the space between the pile members, and concrete is formed in the support holes of the precast member. A technique has been proposed in which each pile member and a precast member are integrated by placing the pile member. Further, after welding a steel bracket to each pile member, installing a precast member on the bracket, and further arranging a bottom formwork around each pile member, between each pile member and the precast member. A technique has been proposed in which concrete is poured into a space to integrate each pile member and a precast member.

However, in the former construction method, the structure of the precast member becomes complicated, and it is necessary to improve the driving position accuracy of each pile member, which causes many problems. On the other hand, in the latter construction method, there is a problem that the corrosion of the bracket progresses after installation, and it is necessary to install a bottom formwork around each pile member for concrete placement at the site, which is also a lot of problems. A point occurs.

In addition, Patent Document 1 has a joint structure of a pile and a beam made of precast concrete, and the beam is provided with a steel frame protruding from the end surface of the precast portion, while the upper end surface of the pile head is provided. The pedestal is connected, and after the steel frame protruding from the beam and the pedestal are connected by welding or the like, concrete is placed between the pile head and the end face of the precast part. A joint structure in which a pile and a beam are joined is disclosed.

Japanese Unexamined Patent Publication No. 8-120638

However, even in the joint structure between the beam and the pile described in Patent Document 1, when concrete is placed between the pile head and the end face of the precast portion, the lower surface of the space between the pile and the end face of the precast portion is used. It is necessary to install a bottom formwork in the concrete, and the above-mentioned problems cannot be solved.

The present invention has been made in view of such a point, and an object of the present invention is to provide an artificial ground capable of improving work efficiency at the time of construction and a construction method thereof.

(Aspect of the invention)
The aspects of the invention shown below exemplify the configurations of the present invention, and are described in terms of terms in order to facilitate understanding of the various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or the like while taking into consideration the best mode for carrying out the invention. Those to which the above-mentioned components are added are also included in the technical scope of the present invention.

(1) An artificial ground formed by connecting floor plates to a plurality of pile members, on a pedestal connected to the pile head of each pile member via a support hole and on the pedestal of the adjacent pile member. Both ends in the longitudinal direction are placed, and a precast beam member erected between the pile members and a space surrounded by the precast beam members on which the peripheral end is placed on the precast beam members. The pedestal is provided with a precast floor plate to cover, and the pedestal is made of reinforced concrete in which a steel material for joining with the pile head is projected inward from the inner wall surface of the support hole. (Corresponding to the invention of claim 1).
Since the artificial ground described in item (1) adopts a configuration in which pedestals are connected to the pile heads of a plurality of pile members, both ends of the precast member in the longitudinal direction are placed on the pedestals of adjacent pile members. It can be mounted and a precast beam member can be erected between each pile member. Further, the peripheral end portion of the precast floor plate can be placed on each precast beam member, and the space surrounded by each precast beam member can be covered by the precast floor plate. As a result, it is not necessary to improve the driving position accuracy of each pile member more than necessary without complicating the shape of the precast floor plate. Thereby, work efficiency can be improved.
Further, since the pedestal is made of reinforced concrete and the necessary cover is secured, it is not necessary to remove the pedestal after installation, and corrosion of the reinforcing bar in the pedestal can be suppressed. Further, the pedestal and the pile member can be connected by joining the steel material protruding from the inner wall surface of the support hole of the pedestal to the outer wall surface of the pile head.

(2) The site of the artificial ground according to the item (1), including the space between the ends of the precast beam members on each pedestal, on each of the precast beam members and on each of the precast floor plates. It is characterized by having a concrete casting layer formed by casting (corresponding to the invention of claim 2).
In the artificial ground described in item (2), concrete is finally cast on each pedestal on each precast beam member including the space between the ends of each precast beam member and on each precast floorboard. When constructing the concrete casting layer, each pedestal, each precast beam member and each precast floor plate functions as a substitute for the conventionally installed support and bottom formwork, so it is necessary to use the support and formwork. It can be minimized, the work of supporting and installing the bottom formwork can be reduced, and the work efficiency can be improved. Moreover, since the support work and the installation work of the formwork can be reduced, the work process at the time of construction can be leveled.

(3) The artificial ground according to the item (1) or (2) , provided with a mortar casting layer formed by casting in the field between the support hole of the pedestal and the pile head. (Corresponding to the invention of claim 3).
In the artificial ground described in item (3 ), the mortar casting layer enables the pedestal and the pile member to be more firmly connected, and further, a steel material projecting inward from the inner wall surface of the support hole of the pedestal. Corrosion can be suppressed.

(4) The artificial ground according to any one of (1) to (3) , wherein the support hole includes a small diameter support hole whose inner diameter substantially matches the outer diameter of the pile head and the small diameter support. It is characterized by having a large-diameter support hole that is continuously formed upward from the hole and has an inner diameter larger than that of the small-diameter support hole.
In the artificial ground described in item (4 ), the small diameter support hole of the pedestal and the outer diameter of the pile head are substantially the same, that is, the pile head can be inserted into the small diameter support hole of the pedestal and has a small diameter. Since the clearance between the inner wall surface of the support hole and the outer wall surface of the pile head is minimized, when placing the mortar between the large diameter support hole of the pedestal and the pile head, the mortar is used for the large diameter of the pedestal. It can be fastened between the support hole and the pile head.

(5) The artificial ground according to any one of (1) to (4), in which the steel materials projecting inward from the inner wall surface of the support hole are at equal intervals along the circumferential direction. A plurality of the steel materials are formed, and the distance between the tips of the opposing steel materials is characterized in that the distance is substantially the same as the outer diameter of the pile head.
In the artificial ground described in item (5 ), the pile head can be positioned substantially concentrically with respect to the support hole of the pedestal, and the positioning accuracy can be improved. Further, the connection strength between the pedestal and the pile head can be made substantially uniform along the circumferential direction.

(6) The artificial ground according to any one of (1) to (5) , wherein the pedestal is formed in a plate shape and a square shape in a plan view.
In the artificial ground described in item (6 ), mounting surfaces can be provided on the upper surface of the pedestal on the peripheral areas of each of the four sides excluding the corners, and the four mounting surfaces of the pedestal are directed toward the pedestal. The ends of the precast beam members extending from the four directions can be placed respectively.

( 7 ) A method of constructing an artificial ground in which a floor plate is connected to a plurality of pile members by inserting support holes provided in the pedestal into the pile heads of the pile members, respectively, and the pedestal and the pile heads. A connecting step for connecting the portions and a beam erection step for placing both ends of the precast beam member in the longitudinal direction on the pedestal of the adjacent pile member and erection the precast beam member between the pile members. , by placing the peripheral end portion of the precast floor on respective precast beam member, seen including a floor plate installation step of covering a space surrounded by the respective precast beam member by the pre-cast floor, the said coupling step, It is characterized by including a positioning step for positioning the pedestal in the height direction with respect to the pile member (corresponding to the invention of claim 4).
The method of constructing the artificial ground described in item (7 ) can significantly improve the work efficiency as compared with the conventional method of constructing a floor board by casting concrete on site. Further, since the connecting step includes a positioning step for positioning the pedestal in the height direction with respect to the pile member, the upper surface of the pedestal connected to each pile member can be made substantially flush with each other, and each precast beam member can be positioned in the substantially horizontal direction. And thus each precast floorboard can be arranged in a substantially horizontal direction. This effect is premised on the fact that each pile member is driven into the seabed or the like so that the height of the top surface thereof is substantially the same.

(8) The method for constructing artificial ground according to item (7), wherein after the floor plate installation step, the space between the ends of the precast beam members is included on the pedestals. It is characterized by providing a floor board placing step of forming the floor board by casting concrete on the precast floor board in the field (corresponding to the invention of claim 5).
In the method of constructing the artificial ground described in item (8 ), each pedestal, each precast beam member, and each precast floor plate are used as a substitute for the conventionally installed support and bottom formwork when the floor plate placing step is carried out. Since it functions, the use of support work and formwork can be minimized, the installation work of support work and bottom formwork can be reduced, and the work process can be leveled and work efficiency can be improved. ..

(9) In the method of constructing the artificial ground according to the item (7) or (8) , in the pedestal, the steel material for joining with the pile head faces inward from the inner wall surface of the support hole. The steel material joining step of joining the steel material of the pedestal to the pile head, the inner wall surface of the support hole of the pedestal, and the pile head after the positioning step. It is characterized by including a mortar placing step of placing a mortar between the outer wall surface and the outer wall surface (corresponding to the invention of claim 6).
In the method of constructing the artificial ground described in item (9 ), in the connecting step, the steel material joining step and the mortar placing step are carried out after the positioning step, so that both are positioned while positioning the pedestal with respect to the pile head. Can be firmly connected.

(10) A plurality of artificial ground construction methods according to any one of (7) to (9) , which are stretched between the upper surface of the pedestal and the top surface of the pile member in the positioning step. The pedestal is positioned in the height direction with respect to the pile member by the positioning rope of the above.
The method of constructing the artificial ground described in item (10 ) can improve the positioning accuracy of the pedestal with respect to the pile member in the height direction.

(11) The method for constructing artificial ground according to any one of (7) to (10) , wherein a fixing plate is provided on the outer wall surface of the pile head between the connecting step and the beam erection step. A pile that includes a plate joining step to be joined, and joins the fixing plate of the pile head and the reinforcing bar projecting from the longitudinal end of the precast beam member between the beam erection step and the floor plate installation step. It is characterized by having a connecting step.
In the artificial ground construction method described in item (11 ), the plate joining step and the pile connecting step are carried out at appropriate timings during the work process from the connecting step to the floor plate installation step, so that the work efficiency in all the steps should be improved. Can be done.

According to the artificial ground and the construction method thereof according to the present invention, the work process can be leveled and the work efficiency can be improved by minimizing the use of support work and formwork at the time of construction. ..

FIG. 1 is a partial perspective view of the artificial ground according to the embodiment of the present invention. FIG. 2 is a perspective view of the artificial ground according to the embodiment of the present invention, in which an appropriate member such as a concrete casting layer is removed so that the internal structure can be easily understood. FIG. 3 is a partial plan view of the artificial ground according to the embodiment of the present invention. FIG. 4 is a cross-sectional view taken along the line AA of FIG. FIG. 5 is a cross-sectional view taken along the line BB of FIG. FIG. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 7A is a plan view of a pedestal adopted for the artificial ground according to the embodiment of the present invention, and FIG. 7B is a cross-sectional view taken along the line DD of FIG. 7A. FIG. 8 is a flow chart of a method of constructing artificial ground according to the embodiment of the present invention. FIG. 9 is a flow chart of connecting steps in the method of constructing artificial ground according to the embodiment of the present invention. 10A and 10B are views for explaining the positioning step and the steel material joining step of FIG. 9, where FIG. 10A is a plan view and FIG. 10B is a cross-sectional view taken along the line EE of FIG. 9A. 11A and 11B are views for explaining the mortar placing step of FIG. 9, where FIG. 11A is a plan view and FIG. 11B is a cross-sectional view taken along the line FF of FIG. 9A. 12A and 12B are views for explaining the plate joining step of FIG. 8, where FIG. 12A is a plan view and FIG. 12B is a cross-sectional view taken along the line GG of FIG. 13A and 13B are views for explaining the beam erection step and the pile connecting step of FIG. 8, where FIG. 13A is a plan view and FIG. 13B is a cross-sectional view taken along the line HH of FIG. 8A. 14A and 14B are views for explaining the floor board installation step of FIG. 8, where FIG. 14A is a plan view, FIG. 14B is a sectional view taken along line II of FIG. It is a cross-sectional view along the JJ line of a). 15A and 15B are views for explaining the bar arrangement step of FIG. 8, where FIG. 15A is a plan view, FIG. 15B is a sectional view taken along the line KK of FIG. It is a cross-sectional view along the LL line of a). 16A and 16B are views for explaining the floor plate placing step of FIG. 8, where FIG. 16A is a plan view and FIG. 16B is a cross-sectional view taken along the line MM of FIG. 8A.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to FIGS. 1 to 16.
The artificial ground 1 according to the embodiment of the present invention is configured by connecting a floor plate 4 to a plurality of pile members, for example, a plurality of steel pipe piles 2. The artificial ground 1 is used, for example, for a horizontal pier type quay or a crossing bridge having a pier type structure.

First, the artificial ground 1 according to the embodiment of the present invention will be described in detail with reference to FIGS. 1 to 7. It should be noted that FIG. 1 is a partial perspective view of the artificial ground 1, and FIG. 2 is a perspective view of the artificial ground 1 so that the internal structure can be easily understood by removing appropriate members such as the concrete casting layer 10. Is. Further, in the attached drawing, reference numeral 50 indicates a reinforcing bar.
As shown in FIGS. 1 to 5, the artificial ground 1 includes a pedestal 6 connected to a pile head 3 of a plurality of steel pipe piles 2 and a precast beam member erected on the adjacent steel pipe piles 2 and 2. Each precast beam member includes 8 and a precast floor plate 9 covering a space surrounded by each of the precast beam members 8 and a space 14 between the ends 8a and 8a of the precast beam members 8 and 8 on each pedestal 6. A concrete casting layer 10 having a substantially flush upper surface, which is provided by casting concrete on the top of the 8 and on each precast floor plate 9, is provided.

As shown in FIGS. 1 and 2, a plurality of steel pipe piles 2 are erected at predetermined intervals. Each steel pipe pile 2 is driven into the seabed or the like so that the height of the top surface thereof is substantially the same. With reference to FIG. 12, the fixing plate 17 is projected outward in the radial direction at a predetermined height at the pile head 3 of each steel pipe pile 2. The fixing plate 17 is composed of four divided plates 18 and 18 and has a square shape in a plan view. The dividing plate 18 is formed in a substantially trapezoidal shape having an arcuate concave portion 21 on one end surface on the short side side thereof. The radius of curvature of the arcuate recess 21 substantially coincides with the radius of the outer wall surface of the pile head 3. The arcuate recesses 21 of each of the divided plates 18 are joined to the outer wall surface of the pile head 3 by welding. As a result, the adjacent dividing plates 18 and 18 are arranged around the pile head 3 so that the sides that do not extend parallel to each other come into contact with each other. Then, a plurality of reinforcing bars 50a projecting from the end portion 8a of the precast beam member 8 described later are joined to the fixing plate 17 projecting from the outer wall surface of the pile head 3 by welding.

As shown in FIGS. 4 and 7, the pedestal 6 has a thick plate shape or a block shape, and is formed in a square shape in a plan view. The pedestal 6 is made of reinforced concrete with the necessary cover secured. On the upper surface of the pedestal 6, the mounting surfaces 27, 27 on which the longitudinal end portions 8a, 8a of the precast beam members 8, 8 are mounted are provided on the peripheral edges of the four sides excluding the corners, respectively. In a plan view, the pedestal 6 has a support hole 5 through which the pile head 3 of the steel pipe pile 2 is inserted through a substantially central portion between the two opposing sides. The support hole 5 is formed in a substantially circular shape in a plan view. The support hole 5 is located at the lower end of the pedestal 6, has a small diameter support hole 5a whose inner diameter substantially matches the outer diameter of the pile head 3, and is gradually expanded upward from the small diameter support hole 5a. It is composed of a large-diameter support hole 5b having a diameter larger than that of the small-diameter support hole 5a and extending in the vertical direction. The clearance between the inner wall surface of the small diameter support hole 5a and the outer wall surface of the pile head 3 is minimized.

A plurality of steel materials 25 are projected inward from the inner wall surface of the large-diameter support hole 5b of the pedestal 6. The steel material 25 is formed in the shape of a thin plate. Each steel material 25 is projected in an upright state. The upper end surface of the steel material 25 and the upper end surface of the pedestal 6 substantially coincide with each other. In the present embodiment, each steel material 25 is formed at four locations at a pitch of 90 ° along the circumferential direction. The amount of protrusion of each steel material 25 from the inner wall surface of the large-diameter support hole 5b is the same. The distance L between the tips of the opposing steel materials 25 substantially coincides with the outer diameter of the pile head 3. That is, the pile head 3 can pass between the tips of the opposing steel materials 25, and the clearance between the tip of each steel material 25 and the outer wall surface of the pile head 3 is minimized. The tip portions of these steel materials 25 are joined to the outer wall surface of the pile head 3 by welding. Further, an annular mortar casting layer 24 formed by casting mortar at the site is formed between the outer wall surface of the pile head 3 and the inner wall surface of the large diameter support hole 5b of the pedestal 6. The thickness of the mortar casting layer 24 in the width direction is not different along the circumferential direction, and is cast so as to be substantially the same over the entire circumference. A plurality of inverted U-shaped hanging hooks 36 are attached to the upper surface of the pedestal 6 at a pitch of 90 ° along the circumferential direction.

As shown in FIGS. 2 to 5, the precast beam member 8 is made of reinforced concrete with the necessary fog secured. The precast beam member 8 is formed to have a length erected between the adjacent steel pipe piles 2 and 2. A plurality of reinforcing bars 50a, 50a project outward from both ends 8a, 8a in the longitudinal direction of the precast beam member 8. These plurality of reinforcing bars 50a are a part of the plurality of main reinforcing bars 50 extending along the longitudinal direction on the lower side in the precast beam member 8. The precast beam member 8 is formed in a substantially T-shaped cross section, has a rectangular cross section and extends along the longitudinal direction, and is projected outward from both ends of the upper portion of the beam main body 32 in the width direction. It is composed of receiving portions 33 and 33, respectively. On the upper surface of the precast beam member 8, a large number of reinforcing bars 50 are projected upward along the longitudinal direction in the range in the width direction excluding the receiving portions 33 and 33.

As shown in FIGS. 2, 3 and 5, the precast floor board 9 is made of reinforced concrete with the necessary fog. The precast floor plate 9 is configured such that peripheral end portions 9a and 9a are placed on the receiving portions 33 and 33 of the precast beam members 8 and cover the space surrounded by the precast beam members 8. The precast floor plate 9 is appropriately formed so that its plan view shape can cover the space surrounded by the precast beam members 8. In the present embodiment, the thickness of the precast floor plate 9 is approximately 1/2 the thickness of the floor plate 4 excluding the beam portion.

As shown in FIGS. 1, 3 and 6, the concrete casting layer 10 includes each precast beam member 8 on each pedestal 6 including a space 14 between the ends 8a and 8a of each precast beam member 8 and 8. Concrete is cast on-site on the top and on each precast floor board 9. The concrete casting layer 10 is a pavement concrete casting layer located above the reinforced concrete casting layer 10a constructed by cast-in-place and having a substantially flush upper surface constructed by cast-in-place. It is composed of 10b and. The thickness of the concrete casting layer 10 on the precast floor board 9 is substantially the same as the thickness of the precast floor board 9. In the present embodiment, the pavement concrete casting layer 10b is not internally laid, but the pavement concrete casting layer 10b may also be reinforced.

Next, the method of constructing the artificial ground according to the embodiment of the present invention will be described with reference to FIGS. 8 to 16.
As shown in FIGS. 8 to 10, first, the connection step S1 for connecting the pedestal 6 and the pile head 3 is performed. In the connection step S1, the positioning step S10, the steel material joining step S11, and the mortar placing step S12 are sequentially carried out.

As shown in FIGS. 9 and 10, in the positioning step S10, the pedestal 6 is positioned with respect to the steel pipe pile 2 in the height direction. Specifically, the support hole 5 of the pedestal 6 is inserted through the pile head 3, and the positioning rope 35 is placed between the top surface of the pile head 3 and each hanging hook 36 provided on the upper surface of the pedestal 6. To stake. The positioning rope 35 is arranged at a pitch of 90 ° along the circumferential direction corresponding to each hanging hook 36 of the pedestal 6. Then, the position of the pedestal 6 in the height direction with respect to the pile head 3 is determined by the tension of each positioning rope 35. By carrying out this positioning step S10, the upper surface of the pedestal 6 supported by each positioning rope 35 on each steel pipe pile 2 becomes substantially flush with each other, and each precast beam member 8 can be arranged in a substantially horizontal direction, and thus each precast beam member 8 can be arranged in a substantially horizontal direction. Each precast floor plate 9 can be arranged in a substantially horizontal direction.

When the positioning step S10 is performed, as shown in FIG. 10, the distance L between the tips of the steel materials 25 facing each other of the pedestal 6 substantially coincides with the outer diameter of the pile head 3, that is, the pedestal. The tip surface of each steel material 25 of No. 6 is in a state of being close to the outer wall surface of the pile head 3 with the minimum clearance. As a result, the radial position of the pile head 3 with respect to the support hole 5 of the pedestal 6 is easily determined. Further, since the distance L between the tips of the opposing steel materials 25 substantially coincides with the outer diameter of the pile head 3, the pile head 3 can be positioned substantially concentrically with respect to the support hole 5 of the pedestal 6. The positioning accuracy can be improved.

Subsequently, the steel material joining step S11 is carried out in a state where the pedestal 6 is lifted by each positioning rope 35, that is, in a state where the pedestal 6 is positioned in the height direction with respect to the pile head 3. In the steel material joining step S11, the tip of each steel material 25 projecting from the inner wall surface of the large-diameter support hole 5b and the outer wall surface of the pile head 3 are joined by welding. As a result, the pile head 3 and the pedestal 6 are connected by the steel materials 25. After connecting the pile head 3 and the pedestal 6 by the steel material joining step S11, each positioning rope 35 is removed from the pile head 3 and the pedestal 6.

Subsequently, as shown in FIGS. 9 and 11, the mortar placing step S12 is carried out. In the mortar placing step S12, the mortar is placed between the inner wall surface of the large-diameter support hole 5b of the pedestal 6 and the outer wall surface of the pile head 3 to form the mortar placing layer 24. At this time, since the inner diameter of the small diameter support hole 5a of the pedestal 6 and the outer diameter of the pile head 3 are substantially the same, the mortar is placed on the inner wall surface of the large diameter support hole 5b of the pedestal 6 and the outer wall surface of the pile head 3. It can be efficiently fastened between and. As a result, the pile head 3 and the pedestal 6 are connected by the mortar placing layer 24. After the mortar placing step S12 is completed, each hanging hook 36 is removed from the pedestal 6.

As described above, in the connecting step S1, after the positioning step 10 is carried out, the steel material joining step S11 and the mortar placing step S12 are carried out, so that the pedestal 6 is placed in the height direction and the horizontal direction with respect to the pile head 3. The pile head 3 and the pedestal 6 can be firmly connected by the plurality of steel materials 25 and the mortar casting layer 24 while positioning along the same. Therefore, since the pile head 3 is positioned and connected to the support hole 5 of the pedestal 6 substantially concentrically, the radial thickness of the mortar casting layer 24 does not differ along the circumferential direction. , It becomes almost the same over the whole circumference.

Next, as shown in FIGS. 8 and 12, the plate joining step S2 is carried out. In the plate joining step S2, the arcuate recesses 21 of the four divided plates 18 as the fixing plates 17 are joined by welding at positions separated from the upper surface of the pedestal 6 by a predetermined distance on the outer wall surface of the pile head 3. As a result, the adjacent dividing plates 18 and 18 are arranged so that one sides that do not extend in parallel with each other come into contact with each other, and a fixing plate 17 having an outer shape having a square shape in a plan view is projected around the pile head 3. be able to.

Next, as shown in FIGS. 2, 3, 8 and 13, the beam erection step S3 is carried out. In the beam erection step S3, both ends 8a and 8a of the precast beam member 8 in the longitudinal direction are placed on the pedestals 6 connected to the adjacent steel pipe piles 2, respectively, and the precast beam is placed between the steel pipe piles 2 and 2. The member 8 is erected. Specifically, both ends 8a and 8a in the longitudinal direction of the precast beam member 8 are placed on predetermined mounting surfaces 27 and 27 in the peripheral area of the pedestals 6 and 6 of the adjacent steel pipe piles 2 and 2, respectively. At this time, on the upper surface of the fixing plate 17 (each divided plate 18) joined to the pile head 3, a plurality of reinforcing bars 50a, 50a projecting from both ends 8a, 8a in the longitudinal direction of each precast beam member 8 are respectively. It will be in contact or close contact.

Next, the pile connection step S4 is carried out. In the pile connecting step S4, the fixing plate 17 (each divided plate 18) joined to the pile head 3 and a plurality of reinforcing bars 50a, 50a projecting from both ends 8a, 8a in the longitudinal direction of each precast beam member 8 And are joined by welding. On the upper surface of the precast beam member 8, a large number of reinforcing bars 50 are projected along the longitudinal direction in the range in the width direction excluding the receiving portions 33 and 33.

Next, as shown in FIGS. 2, 3, 8 and 14, the floor board installation step S5 is carried out. In the floor plate installation step S5, peripheral end portions 9a and 9a of the precast floor plate 9 are placed on the receiving portions 33 and 33 of each precast beam member 8, respectively, and the precast beam member 8 is used by the precast floor plate 9. Arrange so as to cover the enclosed space.

Next, as shown in FIGS. 8 and 15, bar arrangement step S6 is carried out. In the bar arrangement step S6, a large number of reinforcing bars 50 are arranged in the space 14 between the ends 8a and 8a of the precast beam members 8 and 8 on each pedestal 6, and each precast beam member 8 and each precast floor plate are arranged. A large number of reinforcing bars 50 are also arranged in a predetermined height range above 9.

Next, as shown in FIGS. 8 and 16, the floor plate placing step S7 is carried out, and a gap is formed below each precast floor plate 9 between the ends 8a and 8a of the adjacent precast beam members 8. Therefore, in the stage before the floor plate placing step S7, side molds (not shown) are arranged so as to close the gap. Then, in the floor plate placing step S7, on each pedestal 6, each precast beam member 8 including the space 14 between the ends 8a, 8a of each precast beam member 8, 8 and each precast floor plate 9 Concrete is cast on-site to a predetermined height to form a concrete casting layer 10. The concrete casting layer 10 is composed of a reinforced concrete casting layer 10a and a pavement concrete casting layer 10b provided on the upper layer of the reinforced concrete casting layer 10a and having a substantially flush upper surface.
As a result, the concrete casting layer 10, each precast beam member 8, and the floor plate 4 in which each precast floor plate 9 is integrated are constructed, and by extension, the concrete casting layer 10, each precast beam member 8, each precast floor plate 9, and each. An artificial ground 1 in which the steel pipe pile 2 is integrated is constructed.

As described above, in the artificial ground 1 according to the embodiment of the present invention, the pedestal 6 connected to the pile head 3 of each steel pipe pile 2 via the support hole 5, and the adjacent steel pipe pile 2 Both ends 8a and 8a are placed on the pedestals 6 and 6 of 2, respectively, and the precast beam member 8 erected between the steel pipe piles 2 and 2 and the receiving portions 33 and 33 of the precast beam members 8 are placed. A precast floor plate 9 on which peripheral end portions 9a and 9a are placed and covering a space surrounded by each precast beam member 8 and a space 14 between the end portions 8a and 8a of each precast beam member 8 on each pedestal 6 are included. , Each precast beam member 8 and each precast floor plate 9 are provided with concrete cast in the field, and a concrete casting layer 10 having a substantially flush top surface is provided.

As a result, the shapes of the precast beam member 8 and the precast floor plate 9 are not complicated, and the driving position accuracy of each steel pipe pile 2 does not need to be improved more than necessary, so that the work efficiency can be improved. Further, concrete is cast on-site on each precast beam member 8 and on each precast floor plate 9 including the space 14 between the ends 8a and 8a of each precast beam member 8 and 8 on each pedestal 6. When forming the layer 10, each pedestal 6, each precast beam member 8 and each precast floor plate 9 function as a substitute for the support and the bottom formwork, so that the use of the support and the formwork should be minimized. It is possible to level the work process at the time of construction, and it is possible to improve the work efficiency.

Further, in the artificial ground 1 according to the embodiment of the present invention, the pedestal 6 is made of reinforced concrete and is formed in a plate shape and a square shape in a plan view. A steel material 25 for joining with the pile head 3 is projected inward from the inner wall surface of the large-diameter support hole 5b in the pedestal 6. These steel materials 25 are formed at four locations at a pitch of 90 ° along the circumferential direction, and the distance L between the tips of the opposing steel materials 25 substantially coincides with the outer diameter of the pile head 3.

As a result, since the pedestal 6 is made of reinforced concrete and the necessary cover is secured, it is not necessary to remove the pedestal 6 after installation, and corrosion of the reinforcing bar 50 in the pedestal 6 can be suppressed. Further, by making the steel material 25 projecting from the inner wall surface of the large-diameter support hole 5b of the pedestal 6 as close as possible to the outer wall surface of the pile head 3, the pile head 3 is placed on the support hole 5 of the pedestal 6. The pile head 3 can be positioned substantially concentrically, and the tip of the steel material 25 and the outer wall surface of the pile head 3 are joined by welding to position and connect the pile head 3 in the support hole 5 of the pedestal 6. Can be done. Since the pedestal 6 is formed in a plate shape and a square shape in a plan view, mounting surfaces 27 and 27 can be provided on the upper surface of the pedestal 6 on the peripheral edges of each of the four sides excluding the corners. The ends 8a and 8a of the precast beam members 8 extending from the four directions toward the pedestal 6 can be mounted on the mounting surfaces 27 and 27 of the locations, respectively.

Further, in the artificial ground 1 according to the embodiment of the present invention, the support hole 5 of the pedestal 6 has a small diameter support hole 5a whose inner diameter substantially matches the outer diameter of the pile head 3 and upward from the small diameter support hole 5a. It is composed of a large-diameter support hole 5b having a diameter larger than that of the small-diameter support hole 5a and extending in the vertical direction. A mortar casting layer 24 formed by casting mortar is formed between the outer wall surface of the pile head 3 and the inner wall surface of the large-diameter support hole 5b of the pedestal 6. With this mortar casting layer 24, the pedestal 6 and the steel pipe pile 2 can be more firmly connected, and further, corrosion of the steel material 25 projecting inward from the inner wall surface of the support hole 5 of the pedestal 6 is suppressed. can do. Further, since the small diameter support hole 5a of the pedestal 6 and the outer diameter of the pile head 3 are substantially the same, when placing the mortar between the large diameter support hole 5b of the pedestal 6 and the pile head 3 It is possible to prevent the mortar from flowing down from between the large diameter support hole 5b of the pedestal 6 and the pile head 3, and it is possible to improve the work efficiency.

Furthermore, the method of constructing the artificial ground according to the embodiment of the present invention includes the connection step S1, the beam erection step S3, the floor plate installation step S5, and the floor plate placing step S7. Compared with the construction method when the floor board 4 is constructed by casting concrete on site, the work efficiency can be remarkably improved. Further, when the floor board placing step S7 is carried out, the support work and the use of the formwork can be suppressed to the minimum necessary, so that the work process can be leveled and the work efficiency can be improved.

Furthermore, in the method of constructing the artificial ground according to the embodiment of the present invention, the upper surface of the pedestal 6 connected to each steel pipe pile 2 can be arranged substantially flush with each other by the positioning step S10 provided in the connecting step S1. As a result, each precast beam member 8 can be arranged in a substantially horizontal direction, and thus each precast floor plate 9 can be arranged in a substantially horizontal direction. Further, in the connecting step S1, since the steel material joining step S11 and the mortar placing step S12 are performed after the positioning step S10, the pedestal 6 is placed on the pile head 3 while positioning the pedestal 6 with respect to the pile head 3. Can be firmly connected.

1 Artificial ground, 2 Steel pipe pile (pile member), 3 Pile head, 4 Floor board, 5 Support hole, 5a Small diameter support hole, 5b Large diameter support hole, 6 Pedestal, 8 Precast beam member, 8a End, 9 Precast floor board , 9a Peripheral end, 10 Concrete casting layer, 10a Reinforced concrete casting layer, 10b Pavement concrete casting layer, 14 Space, 17 Fixing plate, 24 Mortal casting layer, 25 Steel, 50 Reinforcing bar, 50a Reinforcing bar

Claims (6)

It is an artificial ground made by connecting floor boards to multiple pile members.
A pedestal connected to the pile head of each pile member via a support hole, and
A precast beam member in which both ends in the longitudinal direction are placed on the pedestals of the adjacent pile members and erected between the pile members,
A precast floor plate on which a peripheral end portion is placed on each of the precast beam members and covers a space surrounded by each of the precast beam members.
Equipped with a,
The pedestal is an artificial ground made of reinforced concrete in which a steel material for joining with the pile head is projected inward from the inner wall surface of the support hole. It is characterized by having a concrete casting layer formed by casting on the precast beam member and on the precast floor plate, including the space between the ends of the precast beam members on each pedestal. The artificial ground according to claim 1. The artificial ground according to claim 1 or 2 , wherein a mortar casting layer formed by casting in the field is provided between the support hole of the pedestal and the pile head. It is a construction method of artificial ground made by connecting floor boards to multiple pile members.
A connecting step of connecting the pedestal and the pile head by inserting a support hole provided in the pedestal into the pile head of each pile member.
A beam erection step in which both ends of the precast beam member in the longitudinal direction are placed on the pedestals of the adjacent pile members and the precast beam member is erected between the pile members.
A floor plate installation step in which the peripheral end of the precast floor plate is placed on each of the precast beam members and the space surrounded by the precast beam members is covered by the precast floor plate.
Only including,
A method for constructing artificial ground, wherein the connecting step includes a positioning step for positioning the pedestal in the height direction with respect to the pile member. After the floorboard installation step
A floorboard placing step is provided on each of the pedestals, including a space between the ends of the precast beam members, on each of the precast beam members and on each of the precast floorboards by in-situ casting concrete to form the floorboard. The method for constructing artificial ground according to claim 4 , wherein the artificial ground is constructed. The pedestal is made of reinforced concrete in which a steel material for joining with the pile head is projected inward from the inner wall surface of the support hole.
After the positioning step
A steel material joining step for joining the steel material of the pedestal to the pile head, and
A mortar placing step for placing a mortar between the inner wall surface of the support hole of the pedestal and the outer wall surface of the pile head.
The method for constructing artificial ground according to claim 4 or 5, wherein the method comprises.

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