JP7032758B2 - Pile head reinforcement structure and pile head reinforcement unit - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention can sufficiently secure the stress transmission action and the fixing force, reduce the possibility of interference with the reinforcement arrangement buried in the foundation, and have high strength and high strength as a pile head reinforcing structure. The present invention relates to a pile head reinforcement structure and a pile head reinforcement unit that can improve the construction quality around the pile head by ensuring quality welded joints and can appropriately secure the structural strength.

In order to transmit the force acting on the pile head between the pile and the foundation, the upper side is buried in the foundation, and the lower side has the pile head and the pile head reinforcing member provided so as to be able to transmit stress. Patent Document 1 is known as a reinforcing structure.

The "method of connecting a ready-made pile and a foundation slab" of Patent Document 1 has an object of providing a method of firmly connecting a ready-made pile and a foundation slab with a small amount of reinforcing bars, and has a larger diameter than the outer diameter of the ready-made pile. Then, after attaching a metal short pipe with a guide on the inside and welded reinforcing bars on the outside to the pile head of the ready-made pile, concrete for forming a foundation slab in the gap between the metal short pipe and the ready-made pile is installed. It is filled to reinforce the head of the pile, and the ready-made pile and the formed foundation slab are integrated.

Japanese Unexamined Patent Publication No. 10-266227

In Patent Document 1, a reinforcing bar having a circular cross section is generally welded to a short tube. When using reinforcing bars to transmit the bending moment and axial force acting on the pile head between the foundation and the pile, in order to secure sufficient stress transmission action and to firmly fix the reinforcing bars, the reinforcing bars must be used. The length needs to be 30 to 40 times the diameter of the reinforcing bar, and interference between the reinforcing bar and the reinforcing bar embedded in the foundation occurs.

Further, as the reinforcing bar, a deformed reinforcing bar having irregularities or the like is used in order to secure good fixing, and welding is performed by vertical flare welding, so that the welding technique is extremely difficult and welding defects are likely to occur.

Such a problem is not limited to the case where the reinforcing bar is joined to the short pipe, but is the same even when the reinforcing bar is directly joined to the pile head.

Further, since the force and stress transmission performance in the pile head reinforcing structure is greatly affected by the joint strength by the welded joint, it has been requested to secure the highest possible strength and high quality welded joint.

The present invention has been devised in view of the above-mentioned conventional problems, and it is possible to sufficiently secure the stress transmission action and the fixing force, and there is a possibility that interference with the bar arrangement buried in the foundation may occur. In addition to being able to reduce the amount, it is possible to improve the construction quality around the pile head by ensuring high-strength and high-quality welded joints as a pile head reinforcement structure, and it is possible to appropriately secure the structural strength. It is an object of the present invention to provide a pile head reinforcement structure and a pile head reinforcement unit.

The pile head reinforcing structure according to the present invention is a structure for reinforcing a pile head that protrudes upward from the ground and is buried in the foundation concrete, and the pile is located on the outer peripheral surface side of the pile head. A plurality of plate-like materials are projected outward in the radial direction of the head in a vertical vertical posture and arranged in the circumferential direction of the pile head at appropriate intervals, and the plate-like material is placed on the pile head. It has a first joint portion to be joined to the pile head and a second joint portion to be joined to the plate-shaped material in order to join the portion, and between the pile head and the plate-shaped material. A plate material for stress transmission that transmits stress, a through hole formed through the plate-shaped material in the plate thickness direction, and a pile head from the plate surface around the through-hole in the plate-shaped material. The second joint is provided with a protrusion projecting in the circumferential direction, and the second joint is fitted with a concave groove formed in at least one of the plate-like material and the stress transmission plate material. It is composed of welded joints along the concave groove, and is characterized in that the plate-like material and the stress transmission plate material are embedded in the foundation concrete cast around the pile head.

The stress transmission plate material is provided with at least a pair of upper and lower plates, and is characterized in that it is joined to at least the upper portion and the lower portion of the plate-shaped material in the vertical direction.

The foundation concrete is characterized in that split suppressing bars to which the foundation concrete adheres are arranged on the front and back surfaces of the plate-shaped material so as to intersect the protrusions and the through holes.

The pile head reinforcement unit according to the present invention is a pile head reinforcement unit for reinforcing the pile head that protrudes upward from the ground and is buried in the foundation concrete, and is located on the outer peripheral surface side of the pile head. A plurality of plate-shaped materials, which are projected outward in the radial direction of the pile head in a vertical vertical posture and arranged in the circumferential direction of the pile head at appropriate intervals, and the plate-shaped material. In order to join to the pile head, the pile head and the plate-shaped material have a first joint portion to be joined to the pile head and a second joint portion to be joined to the plate-shaped material. A plate material for stress transmission that transmits stress between the plates, a through hole formed through the plate-shaped material in the plate thickness direction, and a pile in the plate-shaped material from the plate surface to the circumference of the through hole. The second joint is provided with a protrusion protruding toward the circumferential direction of the head, and the second joint is fitted in a concave groove formed in at least one of the plate-shaped material and the stress transmission plate material. It is characterized in that it is composed of welded joints along the concave groove.

The stress transmission plate material is provided with at least a pair of upper and lower plates, and is characterized in that it is joined to at least the upper portion and the lower portion of the plate-shaped material in the vertical direction.

The stress transmission plate material is characterized in that an energy absorbing portion that is more easily deformed than other portions is provided between the first joint portion and the second joint portion.

In the pile head reinforcement structure and the pile head reinforcement unit according to the present invention, the stress transmission action and the fixing force can be sufficiently secured, and the possibility of interference with the reinforcement arrangement buried in the foundation can be reduced. At the same time, as a pile head reinforcement structure, high-strength and high-quality welded joints can be secured, which can improve the construction quality around the pile head and appropriately secure the structural strength.

It is explanatory drawing explaining one preferable embodiment of the pile head reinforcement structure and pile head reinforcement unit which concerns on this invention. It is explanatory drawing explaining the component part of the pile head reinforcement unit used in the pile head reinforcement structure shown in FIG. 1. It is a side view which shows the mode that the pile head reinforcement unit was formed by welding and joining the stress transmission plate material to the plate-like material shown in FIG. It is explanatory drawing explaining the cross-section seen by the arrow of the line AA, the line BB, and the line CC in FIGS. 1 and 3. It is explanatory drawing explaining the deformation example which incorporated the split suppression bar into the pile head reinforcement structure and the pile head reinforcement unit shown in FIG. It is explanatory drawing explaining the other deformation example which incorporated the split | split suppression bar into the pile head reinforcement structure and the pile head reinforcement unit shown in FIG. It is explanatory drawing explaining another modification of the pile head reinforcement structure shown in FIG. It is explanatory drawing explaining another modification of the pile head reinforcement structure shown in FIG. It is explanatory drawing explaining the modification of the pile head reinforcement unit shown in FIG. It is explanatory drawing explaining another modification of the pile head reinforcement unit shown in FIG. 1. It is explanatory drawing explaining another modification of the pile head reinforcement structure shown in FIG. It is explanatory drawing explaining another modification of the pile head reinforcement structure shown in FIG.

Hereinafter, preferred embodiments of the pile head reinforcing structure and the pile head reinforcing unit according to the present invention will be described in detail with reference to the accompanying drawings. 1A and 1B are explanatory views illustrating a preferred embodiment of a pilehead reinforcement structure and a pilehead reinforcement unit according to the present invention, FIG. 1A is a plan view, FIG. 1B is a side view, and FIG. 1B is a side view. FIG. 2 is an explanatory view illustrating the components of the pile head reinforcement unit used in the pile head reinforcement structure shown in FIG. 1, and FIG. 3 shows a stress transmission plate material welded and joined to the plate-shaped material shown in FIG. It is a side view which shows the state.

As shown in FIG. 1, as is well known, the pile 1 is driven into the ground G so that the pile head 2 protrudes upward from the ground G and is installed. In the present embodiment, the pile 1 is a hollow cylindrical pile having a steel pipe portion at least at the pile head 2, and for example, a steel pipe pile (S pile), a concrete pile with an outer shell steel pipe (SC pile), or the like. Used.

In these piles 1, the foundation concrete Q is placed around the pile 1, and when the hollow inside of the pile 1 is also filled with the foundation concrete as pile head filling concrete, or when the foundation concrete Q is not filled, the foundation concrete Q is not filled. In order to close the opening of the pile head 2, a top plate is provided on the upper surface thereof. The pile head 2 including the footing form is embedded in the foundation concrete Q for constructing the foundation together with the foundation reinforcement (not shown) arranged around the pile head 2.

The pile head 2 is a joint portion between the foundation and the pile 1 itself on the ground G side, and bending moments, shear forces, and axial forces act due to various external forces, so that the pile head 2 is reinforced. A pile head reinforcement structure 3 is provided.

As shown in FIGS. 1 to 3, the pile head reinforcing structure and the pile head reinforcing unit according to the present embodiment include a plate-shaped material 4 for engaging the pile head 2 with the foundation concrete Q and a plate-shaped material 4. It is configured to include a stress transfer plate 5 for stress transfer between the pile head 2 and the pile head 2. The pile head reinforcing unit 6 for reinforcing the pile head 2 is configured by the two upper and lower pairs of the stress transmission plate 5 and the one plate-shaped material 4.

The plate-shaped material 4 is made of steel and is formed of a flat plate material having a constant plate thickness, and the plate surface 4a is arranged so as to face laterally in the left-right direction (circumferential direction of the pile head 2), and the length direction is the pile head. 2 is arranged in the radial direction, and the width direction is arranged in the height direction of the pile head 2 and used. The stress transmission plate material 5 is also made of steel and is formed of a flat plate material having a constant plate thickness, and the plate surface 5a is arranged so as to face in the vertical vertical direction (height direction of the pile head 2) and is used.

A plurality of plate-shaped members 4 are arranged on the side of the outer peripheral surface 2a of the pile head 2 at appropriate intervals in the circumferential direction of the pile head 2, preferably at equal intervals. In the illustrated example, four plate-shaped members 4 are arranged around the pile head 2 at intervals of 90 °.

The plate-shaped material 4 is vertically oriented in the vertical direction along the height direction of the pile head 2, and its length direction is projected outward in the radial direction of the pile head 2, and its width direction is It is directed in the height direction of the pile head 2.

In detail, the outer shape of the plate-shaped material 4 is such that the pile side edge 4b facing the pile head outer peripheral surface 2a is formed in a straight line along the height direction of the pile head 2, and the upper and lower sides of the pile side edge 4b are formed. The upper edge 4c and the lower edge 4d extending outwardly outward in the radial direction of the pile head 2 in the length direction from the end are formed in a straight line substantially orthogonal to the pile side end edge 4b, and are formed with the pile side end edge 4b. On the opposite side, the protruding side edge 4e connecting the upper edge 4c and the lower edge 4d is formed in an arc shape without a stake. By forming the protruding side edge 4e that abuts against the foundation concrete Q in an arc shape, it is possible to make it difficult for cracks to occur due to stress concentration.

The plate-shaped member 4 is arranged on the outer peripheral surface 2a side of the pile head 2. In the illustrated example, the height position of the upper edge 4c of the plate-shaped material 4 is the same as or lower than the height position of the upper end 2b of the pile head 2, and the entire plate-shaped material 4 is formed. It is arranged so as to be on the outer peripheral surface 2a side of the pile head 2.

The plate-shaped material 4 is provided with a through hole 7 and a protruding portion 8. In the through hole 7, the foundation concrete Q placed around the pile head 2 is circulated between the front and back surfaces 4a of the plate-shaped material 4, and the filling property of the foundation concrete Q around the plate-shaped material 4 and the plate-like shape are formed. In order to increase the adhesion between the material 4 and the foundation concrete Q and enhance the engaging force of the plate-like material 4 with the foundation (foundation concrete Q), the plate-like material 4 is in the plate thickness direction (periphery of the pile head 2). It is formed sideways through the direction).

In the illustrated example, one through hole 7 is formed in the plate-shaped material 4, but a plurality of through holes 7 may be formed. When forming a plurality of pieces, in order to suppress the amount of protrusion of the pile head 2 from the ground G, arrange them side by side in the length direction of the plate-shaped material 4 so that the vertical width dimension of the plate-shaped material 4 does not become large. Is preferable.

Further, although not shown, a foundation reinforcing bar arranged around the pile head 2 or a separately prepared reinforcing reinforcing bar may be inserted into the through hole 7, whereby the pile head 2 may be inserted. It is possible to further improve the bending force and the shearing force against the acting bending moment and the shearing force.

The protruding portion 8 engages with the foundation concrete Q that is driven around the pile head 2 and flows through the through hole 7 and the foundation concrete Q that adheres to the plate surface 4a of the plate-shaped material 4, and the foundation (foundation concrete Q). Around the through hole 7 in order to further increase the bonding strength to the plate-shaped material 4 and to more reliably transmit the bending moment, shearing force, and axial force acting on the pile head 2 between the pile 1 and the foundation. The plate-shaped material 4 is projected laterally from the plate surface 4a, that is, toward the circumferential direction of the pile head 2. In the illustrated example, the protrusion 8 is provided only on one of the front and back surfaces of the plate-shaped material 4, but it is of course possible to provide the protrusion 8 on both the front and back surfaces.

The plate-shaped material 4 provided with the through hole 7 and the protrusion 8 is not directly joined to the pile head 2 by itself, and therefore, even if it is provided so as to be in contact with the outer peripheral surface 2a of the pile head 2, the outer peripheral surface is provided. A gap S may be provided apart from 2a, and the plate-shaped material 4 is provided by being joined to the pile head 2 via the above-mentioned pair of upper and lower stress transmission plate materials 5. In other words, the joining work of the plate-shaped material 4 to the pile head 2 is not required.

Further, as shown in FIG. 2A, a concave groove 10 is formed in the plate-shaped member 4 in order to form a second joint portion 9 (see FIG. 3) described later. The concave groove 10 is formed in the form of a notch extending in the length direction of the plate-shaped member 4 from the pile side edge 4b.

Specifically, the concave groove 10 of the plate-shaped material 4 is opened at the pile side end edge 4b, and a pair of widthwise groove edges 10a facing each other in the width direction (height direction of the pile head 2) and their lengths. It is partitioned from three directions by one groove bottom 10b opposite to the pile side edge 4b in the direction. The concave grooves 10 of the plate-shaped material 4 correspond to two stress-transmitting plate materials 5 in pairs at the top and bottom, and are located at two locations, specifically, a position lower than the upper edge 4c and the lower edge of the plate-shaped material 4. It is formed as a pair of upper and lower parts at two locations above 4d.

As shown in FIGS. 1 to 3, the stress transmission plate 5 is provided on each of the plurality of plate-shaped members 4 in pairs of upper and lower plates. The stress transmission plate members 5 are provided at appropriate intervals in the circumferential direction of the pile head 2, preferably at equal intervals, in accordance with the arrangement of the plate-shaped members 4. In the illustrated example, four locations are provided around the pile head 2 according to the arrangement of the four plate-shaped members 4.

A pair of upper and lower plates for stress transmission 5 are provided above and below the plate-shaped material 4 provided in a vertical orientation in the vertical direction. The stress transmission plate material 5 provided on the upper portion of the plate-shaped material 4 is provided at a height position lower than the height position of the upper end 2b of the pile head 2 for joining with the pile head 2.

The stress transmission plate material 5 is provided so as to project laterally outward from the pile head 2 in a posture of lying sideways so that the plate surface 5a faces up and down in the height direction of the pile head 2. The stress transmission plate material 5 is approximately composed of a base portion 11 formed in an arc shape along the circumferential direction of the pile head 2 and an extension portion 12 extending radially outward from the base portion 2. It is formed in a T-shaped form.

The base 11 of each stress transmission plate 5 has a length direction in the circumferential direction of the pile head 2 and a width direction in the radial direction of the pile head 2, and the pile side end facing the outer peripheral surface 2a of the pile head 2. By welding and joining the edge 5b to the outer peripheral surface 2a of the pile head 2, a first joining portion 13 for joining the stress transmission plate 5 to the pile head 2 is configured. The width dimension of the base 11 of the stress transmission plate material 5 is the protrusion dimension of the plate-shaped material 4 protruding outward in the radial direction of the pile head 2 (the protruding side edge of the plate-shaped material 4 from the outer peripheral surface 2a of the pile head). It is formed smaller than the distance to 4e).

In the extension portion 12 of each of the two upper and lower plates for stress transmission 5, the circumferential direction of the pile head 2 is the width direction, the radial direction of the pile head 2 is the length direction, and each of the extension portions 12 is In, as shown in FIG. 2A, a concave groove 14 for forming the second joint portion 9 is provided at the center position in the width direction of the tip portion 5c (opposite to the base portion 11) in the length direction. It is formed.

The concave groove 14 is formed in the form of a notch extending in the length direction of the extending portion 12 from the extending portion tip portion 5c. Specifically, the concave groove 14 of the stress transmission plate 5 is opened at the tip portion 5c of the extending portion, and has a pair of widthwise groove edges 14a facing in the width direction (circumferential direction of the pile head 2) and their lengths. It is partitioned from three directions by a groove bottom 14b on the opposite side of the extending portion tip portion 5c in the vertical direction.

As shown in FIG. 3, the stress transmission plate material 5 and the plate-shaped material 4 are formed by fitting the concave grooves 10 and 14 to each other so that the groove bottom 14b and the plate of the concave groove 14 of the stress transmission plate material 5 are fitted to each other. The groove bottoms 10b of the concave groove 10 of the shape material 4 are abutted against each other, and the pair of widthwise groove edges 14a of the concave groove 14 of the stress transmission plate material 4 are along the plate surface 4a of the plate material 4 at the same time. The pair of widthwise groove edges 10a of the concave groove 10 of the shape material 4 are assembled so as to be along the plate surface 5a of the extending portion 11 of the stress transmission plate material 5.

The stress transmission plate material 5 and the plate-shaped material 4 are formed along the concave grooves 10 and 14, that is, the pair of widthwise groove edges 10a and 14a and the plate surface 4a and 5a are formed by the plate-shaped material 4. By welding and joining w with a pair of upper and lower welding lengths that go around the tip portion 5c of the extension portion of the stress transmission plate material 5 from the pile side end edge 4b of the plate-like material 4 and reach the pile side end edge 4b of the plate-like material 4 again. , A second joint portion 9 for joining the stress transmission plate material 5 to the plate-shaped material 4 is configured. The weld joint w is, for example, fillet welding, and may be continuous welding or intermittent welding. Further, the welded joint w does not have to be circulated at the tip portion 5c of the extending portion.

In FIG. 2A, a case where concave grooves 10 and 14 are formed in both the stress transmission plate material 5 and the plate-like material 4 and assembled, and the two are welded and joined w is described. , 14 may be provided on at least one of the stress transmission plate material 5 and the plate-shaped material 4, and as shown in FIG. 2B, the concave groove 10 is formed only in the plate-shaped material 4, and the concave shape is formed. The tip portion 5c of the extension portion of the stress transmission plate material 5 is abutted against the groove bottom 10b of the groove 10, and the pair of widthwise groove edges 10a of the concave groove 10 are assembled along the plate surface 5a of the tip portion 5c. Alternatively, as shown in FIG. 2C, a concave groove 14 is formed only in the stress transmission plate material 5, and the pile side end edge 4b of the plate-like material 4 is abutted against the groove bottom 14b of the concave groove 14. Further, the pair of widthwise groove edges 14a of the concave groove 14 are assembled so as to be along the plate surface 4a of the plate-like material 4, and the second joint portion 9 is formed by performing the welded joint w. good.

In particular, in the configuration shown in FIG. 2A, by fitting the concave grooves 10 and 14 together, both the plate-shaped material 4 and the stress transmission plate material 5 are fixed in positions and set in an orthogonal state. Therefore, the workability at the time of welding can be remarkably excellent. On the other hand, one concave groove 10 may be formed in the center of the plate-shaped material 4 in the vertical width direction, and only one stress-transmitting plate material 5 may be joined.

In the joining of the plate-shaped material 4 and the stress transmission plate material 5 by the second joint portion 9, that is, in the production of the pile head reinforcing unit 6, the stress transmission plate material 5 is welded to the pile head 2 by the first joint portion 13. Workability is good in advance at the factory or on-site. Then, the pile head reinforcing unit 6 provided with the second joint portion 9 is welded to the pile head 2 at the site to form the first joint portion 13.

Regarding the first joint portion 13, the pile side edge 5b of the stress transmission plate material 5 is joined to the pile head 2 by horizontal fillet welding. At this time, the pile side edge 5b is formed in an arc shape along the outer peripheral surface 2a of the pile head 2, and is along the length direction of the base 11 of the stress transmission plate material 5, so that a long welding length can be secured. In order to prevent out-of-plane deformation of the pile head 2, the stress transmission plate material 5 and the pile head reinforcing unit 6 are joined to the pile head 2 with high strength.

For the welded joints of the first and second joints 9 and 13, the stress transfer plate 5 is previously joined to the pile head 2 at the first joint 13, and then the stress transfer plate 5 is joined at the second joint 9. Of course, the plate-shaped material 4 may be joined to the plate material 5.

As shown in FIGS. 1, 3 and 4, the stress transmission plate material 5 is formed with an energy absorbing portion 15 between the first joint portion 13 and the second joint portion 9. 4 (A) is a cross section taken along the line AA in FIGS. 1 and 3, FIG. 4 (B) is a cross section taken along the line BB in FIGS. 1 and 3, and FIG. 4 (C) is a cross section taken along the line BB. And the cross section taken along the line CC in FIG. 3 are shown respectively.

In the second joint portion 9, as shown in FIG. 4A, the plate-shaped material 4 and the stress transmission plate material 5 are fitted to each other to have a large cross-shaped cross-sectional area, and form the first joint portion 13. As shown in FIG. 4C, the base portion 11 of the stress transmission plate 5 is wide and has a large cross-sectional area, whereas the extending portion 12 between the first joint portion 13 and the second joint portion 9 is formed. Is narrower than the base 11 and has a smaller cross-sectional area, as shown in FIG. 4 (B).

As a result, the extending portion 12 between the first joining portion 13 and the second joining portion 9 is most likely to be deformed, and thus functions as an energy absorbing portion 15 in which an energy absorbing action can be obtained.

In addition, as shown in FIGS. 1 and 2, the extension portion 12 of the stress transmission plate 5 gradually extends outward from the base portion 11 of the pile head 2 toward the extension portion tip portion 5c. The widthwise side edge 5d is formed in an inward arc shape in which the extension portion 12 is recessed so that the width dimension is narrowed, whereby the cross-sectional area is set small on the extension portion tip portion 5c side and the energy absorption action is performed. Is configured to be obtained.

In particular, since the widthwise side edge 5d has an inward arc shape, stress can be efficiently transmitted, and the energy absorbing unit 15 can surely cause deformation in advance.

Explaining the operation of the pile head reinforcing structure 3 and the pile head reinforcing unit 6 according to the present embodiment, in the construction thereof, as shown in FIGS. 2 and 3, first, in the factory or the site, the upper part of the plate-shaped material 4 Alternatively, one of the two upper and lower stress transmission plate members 5 is assembled and welded to either one of the lower portions via the concave grooves 10 and 14 to form the second joint portion 9. Then, the other of the other stress transmission plate 5 is similarly assembled and welded to either the lower part or the upper part of the plate 4 through the concave grooves 10 and 14, and the second joint is made. It constitutes a part 9.

As a result, a plurality of plate-shaped material 4 and stress transmission plate material 5 are assembled as an integrated pile head reinforcing unit 6 for joining to the outer peripheral surface 2a of the pile head 2. Since the welded joint w can be operated downward, it can be easily performed with good workability and high welding quality. Further, the plate-shaped material 4 and the stress-transmitting plate material 5 can be welded and joined around the concave grooves 10 and 14 with a pair of long upper and lower weld lengths to prevent brittle fracture at the welded portion and join with high strength. can do.

Next, it was incorporated into each of the plurality of pile head reinforcing units 6 at intervals along the circumferential direction of the pile head 2 on the outer peripheral surface 2a of the pile head 2 protruding upward from the ground G. The pile-side edge 5b of each stress transmission member 5 is joined to the outer peripheral surface 2a of the pile head 2 by horizontal fillet welding, thereby forming the first joint portion 13. As a result, a plurality of plate-shaped members 4 having a through hole 7 and a protruding portion 8 are provided on the pile head 2 so as to project from the pile head 2 in the radial direction.

As for the first joint portion 13, since the welded joint is a downward work, it can be easily performed with good workability and high welding quality.

After that, the foundation concrete Q is placed on the ground G, and the pile head 2 is buried in the foundation concrete Q together with the foundation reinforcement arranged around the pile head 2, so that the foundation is constructed and at the same time. The construction of the pile head reinforcement structure 3 is completed.

The pile head reinforcing structure 3 and the pile head reinforcing unit 6 according to the present embodiment have a through hole 7 and a protruding portion 8, and are projected outward in the radial direction of the pile head 2 in a vertical posture to form a pile. A plurality of plate-shaped members 4 arranged along the circumferential direction of the outer peripheral surface 2a of the head portion 2 and a stress transmission plate material 5 capable of firmly joining and fixing these to the pile head portion 2 by simple and good welding work. Sufficient stress transmission and fixing force can be secured, there is no risk of interference with the foundation reinforcement buried in the foundation, and the reinforcing structure uses few components. The construction quality around the pile head 2 can be improved, and an excellent pile head reinforcing structure 3 can be obtained.

In particular, since the number of parts constituting the pile head reinforcing structure 3 is small and the weight of the structure 3 can be reduced, even the pile head 2 of the large-diameter pile 1 can be reinforced with excellent workability. ..

When the foundation concrete Q is placed, the foundation concrete Q circulates on both the front and back surfaces of the plate-shaped material 4 through the through hole 7, and also adheres to the plate-shaped material 4 and also adheres to the protruding portion 8. Therefore, the pile head reinforcing structure 3 including the plate-shaped material 4 can be firmly joined to the foundation.

As described above, in the pile head reinforcing structure 3 and the pile head reinforcing unit 6 according to the present embodiment, the stress transmission action and the fixing force can be sufficiently secured, and the reinforcing bars are buried in the foundation. The possibility of interference can be reduced, and the pile head reinforcement structure 3 can secure high-strength and high-quality welded joints, thereby improving the construction quality around the pile head 2. The structural strength can be appropriately secured.

In particular, by fitting the concave grooves 10 and 14 together, both the plate-shaped material 4 and the stress transmission plate material 5 can be fixed in position and set in an orthogonal state, and the pile head is reinforced to the pile head 2. The joining accuracy of the unit 6 can be improved, thereby improving the vertical accuracy of the plate-shaped material 4 and the horizontal installation accuracy of the protruding portion 8, and the reinforcing effect of the pile head 2 can be significantly improved. can.

Further, in the second joint portion 9, welding is performed by fitting the concave grooves 10 and 14, so that, for example, the stress transmission plate material 5 is joined to the plate-like material 4 from both the upper and lower sides, which is caused by deformation due to welding heat. It is possible to prevent problems such as broken umbrellas.

Further, the protruding portion 8 can reliably transmit the bending moment, the shearing force, and the axial force acting on the pile head 2 between the pile 1 and the foundation. At this time, the plate-shaped material 4 may be out-of-plane deformed around the protruding portion 8, but by fitting and joining the stress transmission plate material 5 to the plate-shaped material 4, the plate around the protruding portion 8 is formed. The strength of the shape material 4 can be increased.

Since a long welding length can be secured vertically by the concave grooves 10 and 14 constituting the second joint portion 9, the plate-like material 4 provided without welding to the pile head 2 is extended from the stress transmission plate material 5. It is also possible to attach the portion 12 away from the outer peripheral surface 2a via the portion 12, and the workability can be improved.

The plurality of plate-shaped members 4 embedded and fixed in the foundation in this way are projected outward in the radial direction of the pile head 2 in a vertical vertical posture toward the outer peripheral surface 2a of the pile head 2. Therefore, the pile head 2 is provided at appropriate intervals in the circumferential direction, whereby the bending moment, shearing force, and axial force acting on the pile head 2 can be smoothly applied between the foundation and the pile 1. It can be transmitted and the pile head 2 can be firmly reinforced.

Further, since the plate-shaped material 4 is arranged on the outer peripheral surface 2a side of the pile head 2, there is no protrusion upward of the pile head 2, and the plate-shaped material 4 and the stress transmission plate material 5 are embedded in the foundation. It is possible to prevent the foundation from interfering with the reinforcement arrangement of the foundation, and it is possible to improve the workability of the foundation.

When a force in the vertical direction acts on the protruding portion 8 of the plate-shaped material 4, stress due to bending and shearing acts on the pile head 2 around the stress-transmitting plate material 5, but the plate-shaped material 4 in the stress-transmitting plate material 5 Is joined to the pile head 2, so that the pile head 2 can be effectively stiffened and a high-strength pile head reinforcing structure 3 can be obtained.

Since the protrusion 8 is formed so as to surround the through hole 7 from around the protrusion 8, both of the protrusion 8 and the through hole 7 are provided rationally and efficiently as compared with the case where the protrusion 8 and the through hole 7 are formed separately. Even if the external dimensions of the plate-shaped material 4 are small, a large number of these can be provided, and the foundation concrete Q, which flows through the through holes 7 with good filling property, is smoothly fed around the protrusion 8. Therefore, it is possible to secure a solid adhesion between the two.

Since a plurality of plate-shaped materials 4 are arranged around the pile head 2 at intervals, a wide fixing area can be secured by these plurality of plate-shaped materials 4, and the space between the foundation and the pile 1 can be secured. The stress transfer action can be ensured accurately and sufficiently.

In the present embodiment, the plate-shaped material 4 is not welded to the pile head 2, but is provided so as to be separated from the outer peripheral surface 2a with a gap S, and the pile side end edge 5b is the outer peripheral surface of the pile head 2. Stress can be transmitted to the pile head 2 via the arc-shaped stress transmission plate 5 formed along 2a, and when the plate 4 is welded and joined, for example, the pile head is pulled by a force in the vertical direction. It is possible to prevent the pile head 2 from being deformed by stress locally concentrated on the pile head 2 such as out-of-plane deformation in the portion 2, and the stress transmission plate material 5 relaxes the stress on the pile head 2. The stress from the plate-shaped material 4 can be efficiently transmitted to the pile head 2 while ensuring the above.

Since the energy absorbing portion 15 is provided between the first joint portion 13 and the second joint portion 9 on the stress transmission plate material 5, the first and second joint portions 9 and 13 whose stress is a welded portion are provided. It is possible to prevent brittle fracture from occurring by concentrating on the surface.

5 and 6 show modifications of the above embodiment. 5 (A) is a plan view of the split restraining bar 16 incorporated in the pile head reinforcing unit 6, FIG. 5 (B) is a side view thereof, and FIG. 6 is similarly split restraining bar 16 in the pile head reinforcing unit 6. 6 (A) is a side view when the locking groove 17 is formed in the plate-shaped material 4, and FIG. 6 (B) is a side view when the through hole 18 is formed in the plate-shaped material 4. be.

In these modified examples, the split suppressing bar 16 for adhering the foundation concrete Q to the foundation concrete Q and suppressing the splitting fracture is provided in the form of being incorporated in the pile head reinforcing unit 6. The split suppressing bar 16 has a plate-like shape so as to pass through the lower portion of the protrusion 8 in order to cross the protrusion 8 and the through hole 7 on the front and back of the plate surface 4a of the plate-shaped portion 4. It is formed by being folded back in a U shape below the material 4, and thereby extends toward the front and back surfaces 4a of the plate-shaped portion 4.

In FIG. 5, the split suppressing bar 16 is attached and supported to another foundation bar arrangement by a number line or the like, and is provided away from the plate-shaped member 4. In FIG. 6A, a locking groove 17 is formed on the lower edge 4d of the plate-shaped member 4, and the split suppressing muscle 16 is locked in the locking groove 17 for positioning. In FIG. 6B, a through hole 18 is formed in the lower portion of the protrusion 8, and a split suppressing muscle 16 is inserted through the through hole 18 for fixing the position.

According to the locking groove 17 and the through hole 18, the workability can be improved by suppressing the movement of the split suppressing bar 16 when the foundation bar is attached to the foundation bar arrangement by a number wire or the like.

A split crack derived from the protrusion 8 by incorporating the split suppression bar 16 that suppresses the split of the foundation concrete Q into the pile head reinforcing unit 6 and arranging it so as to intersect the through hole 7 and the protrusion 8 of the plate-shaped material 4. Can be prevented from spreading, and the deformation performance of the pile head 2 can be improved. In other words, the pile head reinforcing unit 6 including the through holes 7 and the protrusions 8 can exert the reinforcing action in the foundation portion whose strength is increased by the split restraining muscle 16, and the excellent pile head reinforcing effect is ensured. be able to.

In this modification, the split suppressing bar 16 is exemplified by being formed by being folded back in a U shape at the lower part of the protruding portion 8 of the plate-shaped material 4, but the plate surface 4a on the front and back surfaces of the plate-shaped material 4 is used. As long as it is arranged so as to intersect the through hole 7 and the protrusion 8, the configuration is not limited to this, and for example, a U-shaped folded shape is formed at the upper portion of the protrusion 8. It goes without saying that the reinforcing effect can be improved even if the two linear reinforcing bars (splitting suppressing bars 16) are arranged on the front and back sides of the plate-shaped material 4.

7 and 8 show other modifications of the above embodiment. 7 (A) is a plan view of the pile head reinforcement structure 3 of the large-diameter pile head 2, FIG. 7 (B) is a side view thereof, and FIG. 8 (A) is the pile head reinforcement of the ultra-large-diameter pile head 2. A plan view of the structure 3 and FIG. 8B are side views thereof (the hatched portion is the mounting position of the pile head reinforcing unit 6).

As shown in FIG. 7, in the case of a large diameter, the pile head 2 is appropriately reinforced by providing a large number of pile head reinforcing units 6 shown in FIGS. 1 to 6 in the circumferential direction of the pile head 2. be able to. Further, in the case of the ultra-large diameter shown in FIG. 8, the pile head reinforcing unit 6 is staggered in two stages in the vertical direction and alternately in the circumferential direction with respect to the pile head reinforcing structure 3 shown in FIG. A large number of units 6 can be arranged with good workability, and at the same time, the pile head 2 can be appropriately reinforced in the height direction.

FIG. 9 shows yet another modification of the above embodiment. A large number of stress transmission plate materials 5 may be provided on one plate-shaped material 4, and in this case, as shown in the figure, a large number of concave grooves 10 may be formed according to the number of stress transmission plate materials 5. In the illustrated example, three concave grooves 10 are formed. As a result, when the strength is insufficient, the number of stress transmission plate members 5 can be increased, and the pile head 2 can be appropriately reinforced.

Further, although not shown, a large number of plate-shaped materials 4 may be provided on two stress transmission plate materials 5 in a pair of upper and lower plates. In this case, 12 extending portions extending from the base 11 are the number of plate-shaped materials 4. A large number may be formed according to the above.

FIG. 10 shows still another modification of the above embodiment. In the above embodiment, regarding the energy absorbing portion 15, the widthwise side edge 5d of the extending portion 12 is formed in an arc shape so as to be narrowed outward in the radial direction of the pile head 2, but instead of the arc shape. , The pile head 2 may be formed in a tapered shape whose width dimension narrows outward in the radial direction.

11 and 12 show still other modifications of the embodiment. 11 (A) is a plan view when an additional pile head reinforcing unit 19 is provided on the side of the inner peripheral surface 2d of the pile head 2, FIG. 7 (B) is a side sectional view thereof, and FIG. 12 (A) is. FIG. 12B is a plan view when the additional pile head reinforcing unit 19 is provided in place of the pile head reinforcing unit 6 on the side of the outer peripheral surface 2a of the pile head 2, and FIG. 12B is a side sectional view thereof.

The additional pile head reinforcing unit 19 of these modified examples is projected toward the inner peripheral surface 2d side of the pile head 2 in the radial inward direction of the pile head 2 in a vertical vertical posture. A plurality of plate-shaped lumbers 4 arranged at appropriate intervals in the circumferential direction of 2 and a joint portion and plate-shaped lumber to be joined to the pile head 2 in order to join the plate-shaped lumber 4 to the pile head 2. It has a joint portion to be joined to 4, and is formed through the plate material 5 for stress transmission that transmits stress between the pile head 2 and the plate-shaped material 4 and the plate-shaped material 4 in the plate thickness direction. The through hole 7 is provided, and the plate-shaped lumber 4 is provided with a protruding portion 8 projecting from the plate surface around the through-hole 7 in the circumferential direction of the pile head 2, and the plate-shaped lumber 4 and stress transmission are provided. The joint portion of the lumber 5 is formed by fitting the other into the concave grooves 10 and 14 formed in at least one of the plate 4 and the stress transmission plate 5, and forming a welded joint w along the concave grooves 10 and 14. The plate-shaped material 4 and the stress transmission plate material 5 are embedded in the pile head filling concrete R to be cast inside the pile head 2.

That is, the additional pile head reinforcing unit 19 is such that the pile head reinforcing unit 6 of the above embodiment is provided inside the pile head 2.

In the modified example shown in FIG. 11, in the case of a pile head 2 having a large diameter or an ultra-large diameter, the arrangement of a large number of pile head reinforcing units 6 is complicated in terms of space and work. It is possible to efficiently reinforce the pile head 2 by combining the additional pile head reinforcing unit 19 while avoiding the above.

Further, in the modified example shown in FIG. 12, when it is difficult to dispose the pile head reinforcing unit 6 around the outside of the pile head 2, the additional pile head reinforcing unit 19 rationally increases the pile head. The portion 2 can be reinforced.

Further, when the additional pile head reinforcing unit 19 is provided, the effect of preventing the pile head filling concrete R from slipping is ensured inside the pile head 2, and the stress generated in the pile head 2 can be efficiently transmitted. ..

In the above embodiment, all the protruding portions 8 of the plate-shaped member 4 are projected in the same direction in the circumferential direction of the pile head 2, but some of them may be projected in the opposite directions.

2 Pile head 2a Pile head outer peripheral surface 3 Pile head reinforcement structure 4 Plate-shaped material 4a Plate-shaped material plate surface 5 Stress transmission plate material 6 Pile head reinforcement unit 7 Through hole 8 Protruding part 9 Second joint 10, 14 Concave groove 13 1st joint 15 Energy absorption part 16 Split suppression bar G Ground Q Foundation concrete w Welded joint along the concave groove

Claims (6)

It is a structure to reinforce the pile head that protrudes upward from the ground and is buried in the foundation concrete.
A plurality of pile heads are projected on the outer peripheral surface side of the pile head in a vertical vertical direction outward in the radial direction, and are arranged in the circumferential direction of the pile head at appropriate intervals. Plate-shaped material and
In order to join the plate-shaped material to the pile head, the pile head has a first joint portion to be joined to the pile head and a second joint portion to be joined to the plate-shaped material. A stress transfer plate material that transmits stress between the plate-shaped material and the plate material
Through holes formed in the plate-shaped material through the plate-like material in the plate thickness direction,
The plate-shaped material is provided with a protrusion protruding from the plate surface around the through hole toward the circumferential direction of the pile head.
The second joint portion is composed of a welded joint in which the other is fitted into a concave groove formed in at least one of the plate-shaped material and the stress transmission plate material, and the other is welded along the concave groove.
A pile head reinforcing structure characterized in that the plate-shaped material and the stress transmission plate material are embedded in the foundation concrete placed around the pile head. The pile head reinforcing structure according to claim 1, wherein at least a pair of upper and lower plates for stress transmission is provided and joined to at least upper and lower portions of the plate-shaped material in the vertical direction. The claim is characterized in that, in the foundation concrete, split-suppressing bars to which the foundation concrete adheres are arranged on the front and back surfaces of the plate-like material so as to intersect the protrusions and the through holes. The pile head reinforcement structure according to 1 or 2. It is a pile head reinforcement unit for reinforcing the pile head that protrudes upward from the ground and is buried in the foundation concrete.
A plurality of pile heads are projected on the outer peripheral surface side of the pile head in a vertical vertical direction outward in the radial direction, and are arranged in the circumferential direction of the pile head at appropriate intervals. Plate-shaped material and
In order to join the plate-shaped material to the pile head, the pile head has a first joint portion to be joined to the pile head and a second joint portion to be joined to the plate-shaped material. A stress transfer plate material that transmits stress between the plate-shaped material and the plate material
Through holes formed in the plate-shaped material through the plate-like material in the plate thickness direction,
The plate-shaped material is provided with a protrusion protruding from the plate surface around the through hole toward the circumferential direction of the pile head.
The second joint is characterized in that the other is fitted into a concave groove formed in at least one of the plate-shaped material and the stress transmission plate material, and the second joint is formed by welding along the concave groove. Pile head reinforcement unit. The pile head reinforcing unit according to claim 4, wherein at least a pair of upper and lower plate members for stress transmission is provided, and the plate members are joined to at least the upper portion and the lower portion of the plate-shaped members in the vertical direction. The fourth or fifth aspect of the present invention, wherein the stress transmission plate material is provided with an energy absorbing portion between the first joint portion and the second joint portion, which is more easily deformed than other portions . Pile head reinforcement unit.

Images