JPH0841922A - Grout flow out preventing seal member between pile and sheath pipe and seal structure using this seal member - Google Patents

Abstract

PURPOSE:To enlarge load resistance by extendedly providing a seal part fixed to the inner periphery of a sheath pipe obliquely upward to make a load act toward a fixed base part. CONSTITUTION:A seal member 1 is composed of elastic raw material such as synthetic rubber or the like, and seal part 20 is extendedly provided obliquely upward in a central direction.in a conical shape from a cylindrical fixed base part 10 having an outer diameter corresponding to the bore of the attached sheath pipe, and an opening part being smaller as much as a fixed quantity than the outside diameter of a pile is formed at the tip of the seal part. The side of the fixed base part 10 is thinner than the seal part 20 so as to be easy in bending. In addition, a reinforcing cord 30 is internally inserted along an outer face from the fixed base part 10 about to a center in the lateral direction of the seal part 20 for improving bending rigidity to the fixed base part 10. The tip 22c of the seal part is elastically deformed in a diameter enlarging direction by inserting a pile 2 through the sheath pipe 3 having the attached seal member 1, and a continuous spot between the seal part 20 and a fixed part 10 therefore bends to rise upward, and its elastic recovering force brings the lower face side of the tip 22c into pressure contact with the outer periphery 2A of the pile 2 to form a sealing state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foundation method for extrapolating a sheath tube integrated with a structure into a pile driven into the ground and fixing it with grout. The present invention relates to a grout outflow prevention seal member between a pile and a sheath tube, and a seal structure using the seal member, which is interposed between the piles and prevents the grout filled above the interposed portion from flowing down.

[0002]

2. Description of the Related Art Conventionally, as a method of constructing a structure on the sea or on a river, a pile such as a steel pipe or concrete is previously driven into the ground, and a sheath pipe made of a concrete pipe or the like attached to the construct is mounted on the pile. In some cases, the space between the pile and the sheath tube is filled with grout and fixed together to form a foundation. In such a construction method, the seal member for preventing the grout filled between the pile and the sheath pipe from flowing out from the lower end portion of the sheath pipe is formed by an elastic body such as rubber to have an L-shaped cross section. It has been known.

[0003]

However, with the conventional sealing member, it is difficult to allow a large eccentricity of the sheath tube with respect to the pile, and relatively high accuracy is required for the interval between the pile and the sheath tube. In addition to increasing costs, construction may be difficult depending on the construction,
There has been a demand for a seal member and a seal structure capable of allowing greater eccentricity of the sheath pipe with respect to the pile and absorbing an error in the installation interval of the pile and the sheath pipe.

In order to increase the allowable eccentricity range between the pile and the sheath pipe, it is necessary to increase the difference between the outer diameter of the pile and the inner diameter of the sheath pipe (the distance between the outer peripheral surface of the pile and the inner peripheral surface of the sheath pipe). However, if a conventional seal member having an L-shaped cross-section is enlarged in a similar shape to deal with this, in order to withstand the pressure of the grout filled in the enlarged space, the thickness of the seal portion or the fixed portion is increased. Increasing the thickness is unavoidable, the flexibility of the seal part is reduced and the large-sized fixing part occupies the space between the outer peripheral surface of the pile and the inner peripheral surface of the sheath pipe, and the eccentric allowable space is narrowed, The eccentricity allowable range did not increase as the size of the sealing member was increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and allows a greater eccentricity of a sheath tube with respect to a pile to absorb an error in the installation interval of the pile and the sheath tube, thereby reducing construction costs. It is an object of the present invention to provide a grout outflow prevention seal member between a pile and a sheath pipe, and a seal structure using the seal member, which can reduce the size and improve the degree of freedom of construction.

[0006]

A seal member for preventing grout from flowing out between a pile and a sheath pipe according to the present invention, which achieves the above object, is fixed by grout by externally inserting a sheath pipe integrated with a structure into a pile driven into the ground. In the foundation method to be, a seal member that is interposed between the outer peripheral surface of the pile and the inner peripheral surface of the sheath tube and that prevents grout from being filled above the interposed portion,
A sealing portion having a tapered thickness extends obliquely upward in the center direction from an upper edge portion of a cylindrical fixed base formed along an inner periphery of the sheath tube and formed at a predetermined amount from the pile. It is characterized in that a small-diameter opening is formed, and interdigital reinforcing cords are inserted from the fixed base portion to the seal portion so that the fiber direction is parallel to the central axis direction.

A cylindrical fixing ring is adhered to the outer periphery of the fixing base of the sealing member in an externally inserted state.
The seal member is configured to be fixed to the inner periphery of the sheath tube via a fixing ring.

In a seal structure using the above-mentioned seal member, the seal member is formed by an L-shaped fixing bracket having a support portion extending toward the center portion at the upper edge, and the fixing base portion is formed on the inner peripheral side. And is pressed against and fixed to the inner periphery of the sheath tube.

Further, in addition to the above-mentioned sealing structure, an escape groove is formed in the inner circumference of the sheath tube for accommodating a seal member in which the seal portion is elastically deformed to the same diameter as the fixed base portion, and the seal member is formed. Is fixedly provided in the escape groove.

[0010]

In the sealing member constructed as described above, the fixing base is fixed to the inner peripheral surface of the sheath tube, the sealing portion is elastically deformed in the radially expanding direction, the pile penetrates through the opening, and the tip of the sealing portion. Is pressed against the outer peripheral surface of the pile by its elastic restoring force to prevent the grout filled above from flowing downward. Since the seal portion extends obliquely upward, the load from the grout acts toward the fixed base portion (a component force in the direction of compressing the seal portion in the longitudinal direction is generated),
It can withstand the load without increasing the thickness, and the wide width of the seal makes it easier to deform when eccentricity is allowed. A large amount of deformation can be obtained. In addition, the interdigitated reinforcing cord inserted from the fixed base to the seal portion enhances rigidity in a bending direction in which the seal portion falls down without hindering radial expansion deformation of the seal portion. Is prevented from bending downward, thereby preventing reversal to the lower side.

Further, in a structure in which a cylindrical fixing ring is adhered to the outer periphery of the fixed base in an externally inserted state and fixed to the inner periphery of the sheath tube through the fixing ring, the fixing can be easily performed.

Also, in the seal structure using the above-mentioned seal member, the seal member has a fixed base portion by means of a fixture having an L-shaped cross section having a support portion extending toward the center side at the upper edge. Is fixed by being pressed from the inner peripheral side to the inner peripheral side of the sheath pipe, the support part of the upper edge of the fixing metal fitting supports the seal part of the seal member from the lower side, so that the seal part is not inverted to the lower side. prevent.

[0013] In addition to the above-mentioned sealing structure, a clearance groove is formed in the inner periphery of the sheath tube so as to accommodate a sealing member in which the sealing portion is elastically deformed to the same diameter as the fixed base. In this case, the seal member does not occupy the space between the outer peripheral surface of the pile and the inner peripheral surface of the sheath tube, and the gap between the outer peripheral surface of the pile and the inner peripheral surface of the sheath tube is eccentric. Available to tolerance.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view of a seal member which is an embodiment of a grout outflow prevention seal member between a pile and a sheath tube according to the present invention, FIG. 2 is a cross-sectional view of the seal member along AA, and FIG. It is a longitudinal section of the used seal structure.

The illustrated seal member 1 is entirely made of an elastic material such as synthetic rubber or natural rubber, and has a cylindrical fixed base portion 10 having an outer diameter corresponding to the inner diameter of the sheath tube to be mounted.
From the upper edge of the pile, a seal portion 20 extends conically obliquely upward in the center direction, and its tip forms an opening 20A having a diameter smaller than the outer diameter of the pile by a predetermined amount.

The thickness of the fixed base 10 is thinner than the base of the seal portion 20 that is continuous with the fixed base 10, and the rear surface is smoothly continuous with a curved line. The step portion 11 is formed so as to protrude inward from the inner peripheral surface of the step 10. That is, in the continuous portion of the fixed base portion 10 and the seal portion 20, the fixed base portion 10 side is thinner than the seal portion 20, and the portion is easily bent.

The lower surface 21 of the seal portion 20 is formed at an angle of θ = 35 ° with respect to a horizontal line. The upper surface 22 has a slightly shallower angle than the lower surface 21 and has a substantially horizontal step 22A formed near the front end.
B is formed. As a result, the seal portion 20 has a tapered shape in which the thickness gradually decreases toward the tip as a whole, and the tapered shape and the thickness thereof are set so as to correspond to the pressure moment applied by the load of the grout. It has been done.

As shown in FIG. 4, which is a cross-sectional view showing a sealing structure in which the sealing member 1 is mounted on the sheath tube 3, the tip portion 22C (inner peripheral edge) of the sealing portion 20 has a radial width. The width is set to a value obtained by adding twice the minimum allowable width of eccentricity between the pile and the sheath tube: b to the minimum interference width: a that generates a contact pressure capable of sealing by contacting the outer surface. Therefore, when the pile 2 and the sheath pipe 3 are concentrically provided as shown in FIGS.
The outer peripheral surface 2A of the pile 2 is located exactly in the center of the eccentricity allowable range (from this state, the eccentricity allowable width: b can be eccentric), and the tip 22C of the seal portion 20 has the eccentricity allowable width: b of the minimum interference width. : The width added with a interferes with the pile 2. In this embodiment, the eccentricity is allowed until the outer peripheral surface 2A of the pile 2 and the inner peripheral surface 3A of the sheath tube 3 come into contact with each other. Therefore, the eccentric permissible width: b indicates that the pile and the sheath tube 3 are provided concentrically. In this case, it is equal to the distance between the outer peripheral surface of the pile and the inner peripheral surface 3A of the sheath tube 3.

From the fixed base portion 10 to the vicinity of the approximate widthwise center of the seal portion 20, the outer surface side (bending rear surface side) from the thickness center.
The reinforcement cord 30 is inserted along the outer surface at an inner position where. The reinforcing cord 30 has a so-called interdigital shape in which fibers are arranged in parallel in one direction, and as shown in the conceptual diagram of FIG. It is inserted around the circumference. As the fibers, synthetic fibers such as vinylon and nylon are used. In this embodiment, fibers having a thickness of 1000 to 1200 denier and a strength of 120 kg / cm or more are arranged at a density of 40 fibers / 5 cm or more.

The interdigital reinforcing cord 30 strongly resists a force in which the fiber is pulled in the longitudinal direction. Therefore, the insertion position of the reinforcing cord 30 in the direction in which the sealing portion 20 falls with respect to the fixed base 10 is the center of the thickness. Since it is on the outer surface side, the fiber is pulled in the longitudinal direction and acts to improve its bending rigidity. On the other hand, when the seal portion 20 bends in the rising direction with respect to the fixed base portion 10, the reinforcing cord 30 is in a loosening direction and therefore does not contribute to the improvement of rigidity. Further, in the fiber arrangement direction of the reinforcing cord 30. Deformation in the circumferential direction of a certain seal portion 20 (deformation in the direction indicated by the arrow in FIG. 3) is not hindered. As a result, the sealing member 1 exhibits high rigidity in bending in the direction in which the sealing portion 20 falls with respect to the fixed base portion 10, and is made of a material in a direction in which the sealing portion 20 rises and a direction in which the opening 20 </ b> A of the sealing portion 20 expands in diameter. It is flexible due to the elasticity of rubber. That is, the seal part 2
0 is difficult to bend in the direction in which it falls with respect to the fixed base portion 10, but is easily deformed in the rising direction or the radial direction.

The sealing member 1 configured as described above is fixed to the inner periphery of the sheath tube 3 as shown in FIG. 4 to form a sealing structure.

An escape groove 31 is formed continuously in the circumferential direction at the position of the inner peripheral surface of the sheath tube 3 to which the seal member 1 is mounted, and an anchor bolt 32 is provided near the lower end of the escape groove 31 at the tip thereof. Is planted so that it projects toward the inner circumference.

The inner peripheral surface of the escape groove 31 is fixed to the seal member 1 by a fixing fitting 4 which is fastened by a nut 5 to a tip of an anchor bolt 32 whose fixing base 10 penetrates the fixing base 10 and protrudes inward. To be fixed.
The tips of the fixing bracket 4, the nut 5, and the anchor bolt 31 are accommodated in the escape groove 31 so as not to protrude inside the inner peripheral surface 3A of the sheath tube 3.

The fixed metal fitting 4 is a fixed base portion 1 of the seal member 1.
A support portion 42 is provided on the upper edge of the cylindrical portion 41 corresponding to the inner circumference of
Is formed so as to protrude toward the inner peripheral side, and has a substantially L-shaped cross section.
It is provided in contact with the lower side of the step portion 11 above the zero.

The clearance groove 31 has a depth capable of accommodating the seal member 1 in a state of being bent and deformed in a direction in which the seal portion 20 extending obliquely upward from the fixed base 10 rises until the seal portion 20 becomes straight with the fixed base 10. The width is set so that when the seal portion 20 of the seal member 1 is bent and deformed in a direction in which the seal portion 20 rises until the seal portion 20 becomes straight with the fixed base portion 10,
It is designed to completely fit in the escape groove 31.

When the pile 2 is inserted into the sheath tube 3 on which the sealing member 1 is mounted, as shown in FIG. 5, the tip 22C (the inner peripheral edge) of the seal portion 20 which interferes with the pile 2 is elastically expanded in the radial direction. At the same time, the continuous portion of the seal portion 20 and the fixed portion 10 bends and rises upward, and the elastic return force causes the seal portion 2 to move upward.
The lower surface side of the tip 22C of 0 is pressed against the outer peripheral surface 2A of the pile 2 to be in a sealed state. In FIG. 5, the center of the pile 2 and the center of the sheath tube 3 coincide with each other. Therefore, the interval between the outer peripheral surface 2A of the pile 2 and the inner peripheral surface 3A of the sheath tube 3 has a gap: b equal to the eccentric allowable width. It shows the state where it is.

The sealing member 1 fixed to the sheath tube 3 as described above acts on the pressure of the filled grout as described below to maintain the sealed state.

FIG. 6 shows a state where grout is filled in FIG. When the grout 6 is filled, the grout 6 is loaded on the upper surface of the seal portion 20 of the seal member 1, whereby a force for bending the seal portion 20 in the direction of falling with respect to the fixed base 10 is applied. As described above, the seal member 1 has high rigidity due to the reinforcing cord 30 inserted in the bending direction of the seal portion 20 as described above. In addition to this, the end surface of the seal portion 20 on the fixed base 10 side. Is supported by the support portion 42 of the fixture 4, the downward bending of the seal portion 20 is small, and a good sealing state can be maintained. Further, since the seal portion 20 has an upward angle, the pressure escapes as a component force toward the fixed base portion 10 as compared with the horizontal case, and this component force compresses the seal portion 20 in the width direction. As a result, the load resistance is large, and there is little possibility that the sheet will be turned downward. Furthermore, since the seal portion 20 is wider than the horizontal one because it is diagonal, the deformation rate is small even if the amount of interference with the pile 2 is the same, and a larger deformation width is allowed. Easy to do. From these points, the larger the angle θ from the horizontal of the seal portion 20 is, the more effective it is.
Since the width is widened by increasing the angle: θ, it is uneconomical because many materials are required. For this reason, considering the function and economy, it is considered that the range of 30 ° to 40 ° is preferable.

Next, the allowable action of the eccentricity between the pile 2 and the sheath pipe 3 will be described. If the center of the pile 2 and the center of the sheath tube 3 match,
As shown in FIG. 7, the outer peripheral surface 2A of the pile 2 and the inner peripheral surface 3 of the sheath tube 3
A gap b equal to the eccentric permissible width is formed in the entire circumference between A, and the tip 22C of the seal portion 20 is elastically deformed by interference with the pile 2 at the width obtained by adding the eccentric permissible width to the minimum interference width. The same deformation state is exhibited over the circumference.

On the other hand, when the sheath tube 3 is eccentrically inserted into the pile 2 and extrapolated, the width of the seal portion 20 is reduced to the minimum interference width as described above. (The distance between the outer peripheral surface 2A of the pile 2 and the inner peripheral surface 3A of the sheath tube 3 in the case of concentricity)
Since the width is set to be twice the above, the sealed state is maintained even if eccentric until the inner peripheral surface 3A of the sheath tube 3 comes into contact with the outer peripheral surface 2A of the pile 2. That is, as shown in FIG.
When the inner peripheral surface 3A is eccentric until it comes into contact with the outer peripheral surface 2A of the pile 2, the sealing portion 20 is elastically deformed until it becomes substantially linear with the fixed base 10 on the side X where the interval becomes narrower, and fits in the escape groove 31. The entire seal portion 20 is pressed against the outer peripheral surface 2A of the pile 2 and the seal portion 20 on the opposite side Y where the interval is increased is pressed against the outer peripheral surface 2A of the pile 2 by deformation due to interference of the pile 2 with the minimum interference width, Both sides are kept sealed.

According to the seal member and the seal structure using the seal member as described above, it is possible to withstand a large pressure without increasing the thickness of the seal portion, and therefore, it is possible to set a large allowable eccentric width. It becomes possible.

Although the seal member 20 is configured to be housed in the escape groove 31 formed in the inner peripheral surface 3A of the sheath tube 3 in the above embodiment, the escape groove 31 is not essential. However, although the allowable eccentricity width is reduced by the thickness of the seal member 1, the seal member 1 may be directly fixed to the inner peripheral surface 3A of the sheath tube 3.

FIG. 9 shows another embodiment of the structure for fixing the sealing member to the inner periphery of the sheath tube. Note that parts having the same functions as those in the above-described embodiment are given the same reference numerals with dashes ('), and description thereof is omitted. In the illustrated embodiment, a cylindrical metal fixing ring 13 is baked and adhered to the outer periphery of the fixed base portion 10 'of the seal member 1'in an externally attached state. According to this configuration, the fixing ring 13 is attached to the inner peripheral surface 3A 'of the sheath tube 3' by arranging a steel plate on the inner periphery of the sheath tube of concrete as well as the case of using the sheath tube made of steel tube. By welding, the sealing member 1 ′ can be fixed to the sheath tube 3, and the mounting operation is facilitated and the operation efficiency is improved.

[0034]

As described above, according to the seal member for preventing grout outflow between the pile and the sheath pipe according to the present invention, since the seal portion is obliquely extended upward, the load by the grout is fixed to the fixed base portion. Since it acts toward the side, it is possible to withstand the load without increasing the thickness, and it is possible to obtain a large allowable deformation width due to the wide width of the seal portion. In addition, the interdigitated reinforcing cord inserted from the fixed base to the seal portion improves rigidity in the bending direction in which the seal portion falls down without hindering radial expansion deformation of the seal portion, and the seal portion due to the load of the grout. To prevent downward bending and also prevent downward inversion.
This makes it possible to set a large allowable eccentricity without increasing the thickness of the fixed base or seal, allowing a larger eccentricity of the sheath pipe with respect to the pile and reducing the installation interval error of the pile and the sheath pipe. It can be absorbed, which can contribute to reduction of construction cost and improvement of construction flexibility.

Further, in a structure in which a cylindrical fixing ring is adhered to the outer circumference of the fixed base in an externally inserted state and fixed to the inner circumference of the sheath tube through the fixing ring, it can be fixed to the sheath tube by welding. It becomes possible, the mounting work becomes easy, and the work efficiency improves.

The fixing base of the sealing member is pressed and fixed from its inner periphery to the inner periphery of the sheath tube by an L-shaped fixing bracket having a support portion extending toward the center at the upper edge. In such a seal structure, the support portion of the fixing member supports the lower side of the seal portion of the seal member, prevents the seal portion from bending downward, and prevents the seal portion from turning downward. Accordingly, it is possible to set the eccentric permissible width to a large value without increasing the thickness of the fixed base portion and the seal portion of the seal member.

[0037] An escape groove is formed in the inner periphery of the sheath tube so as to accommodate a seal member in which the seal portion is elastically deformed to the same diameter as the fixed base, and the seal base has a lower end in the escape groove. With the configuration fixed to the part, the seal member does not hinder the eccentricity of the pile and the sheath tube, and the entire interval between the outer peripheral surface of the pile and the inner peripheral surface of the sheath tube is used for eccentric absorption. Becomes possible.

[Brief description of drawings]

FIG. 1 is a perspective view of a seal member which is an embodiment of a grout outflow prevention seal member between a pile and a sheath tube according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory diagram conceptually showing an interpolation state of a reinforcing cord.

FIG. 4 is a cross-sectional view of a state in which the seal member, which is one embodiment of the seal structure using the seal member according to the present invention, is attached to a sheath tube.

FIG. 5 is a cross-sectional view showing a state in which the sheath pipe is externally inserted into the pile and the seal member is deformed.

6 is a cross-sectional view showing a state in which grout is further filled in the state of FIG.

FIG. 7 is a cross-sectional view showing a state where a sheath tube is concentrically extrapolated to a pile.

FIG. 8 is a cross-sectional view showing a state where the sheath tube is eccentrically inserted into the pile and extrapolated.

FIG. 9 is a sectional view of another embodiment of the seal member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Seal member 2 ... Pile 3 ... Sheath tube 4 ... Fixing bracket 6 ... Grout 10 ... Fixing base 13 ... Fixing ring 20 ... Sealing part 20A ... Opening 30 ... Reinforcement cord 31 ... Escape groove 42 ... Supporting part

Claims (4)

[Claims] 1. A foundation method for extrapolating a sheath tube integrated with a structure to a pile driven into the ground and fixing it with grout, interposed between an outer peripheral surface of the pile and an inner peripheral surface of the sheath tube, A seal member for preventing the grout from being filled above the interposed portion from flowing down, the seal member being formed of an elastic material, and having a thickness from an upper edge of a cylindrical fixed base along an inner periphery of the sheath tube. A tapered seal portion extends obliquely upward in the center direction, the tip of the seal portion forms an opening having a smaller diameter than the pile by a predetermined amount, and the interdigital reinforcement cord from the fixed base portion to the seal portion has its center in the fiber direction. A grout outflow seal member between a pile and a sheath tube, wherein the seal member is inserted and inserted parallel to an axial direction. 2. A cylindrical fixing ring is adhered to an outer periphery of a fixing base of the sealing member in an extrapolated state, and the sealing member is fixed to an inner periphery of the sheath tube via the fixing ring. The grout outflow prevention seal member between the pile and the sheath tube according to claim 1, wherein the seal member is configured so as to be configured as described above. 3. The sealing member has an L-shaped cross-section having a support portion extending toward a center portion at an upper edge, and a fixing base portion of the sealing member is formed on an inner peripheral side of the sheath tube from an inner peripheral side. The seal structure using the grout outflow prevention seal member between the pile and the sheath tube according to claim 1, wherein the seal member is pressed and fixed. 4. An inner periphery of the sheath tube is provided with a clearance groove for accommodating the seal member whose seal portion is elastically deformed to the same diameter as the fixed base portion, and the seal member is provided with the relief groove. The seal portion structure according to claim 3, wherein the seal portion structure is provided fixed in the groove.