JP2011080600A - Sheath pipe jacking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheath pipe jacking method eliminating the fall-in of casters. <P>SOLUTION: The jacking method for constructing a conduit by feeding pipes P into a sheath pipe P' while inserting a spigot 1 of the pipe P into a socket 2 of the preceding pipe P and joining them together is carried out by guiding the travel of the pipes P in the sheath pipe P' by the casters 24 provided around the pipes P. A plurality of casters 24 are provided in front and in the rear in a pipe axis direction, and even if one caster 24 corresponds to a joint recess b' between the sheath pipes P', P', the other casters 24 abut on the inner surface of the sheath pipe P' and prevent the one caster 24 from being fitted into the joint recess b' to carry out jacking. In this manner, even if the one caster 24 corresponds to the joint recess b', the other casters 24 abut on the inner surface of the sheath pipe P' to obtain the smooth traveling (jacking) of the pipes P with no risk of the one caster falling into the joint recess b'. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sheath pipe construction method in which a pipe for transporting fluid used for water supply, gas, sewerage, etc. is laid without opening.

  As a method of embedding fluid transport pipes such as ductile cast iron pipes, the open-cut method of excavating and laying the ground has been common, but nowadays traffic volume has increased not only on main roads but also on general roads. Therefore, it is difficult to block traffic due to the open-cut method. For this reason, only the start pit and the access pit are excavated and a ductile cast iron pipe is inserted after a fume pipe or steel pipe is propelled and buried as a sheath pipe (sheath pipe), or an existing pipe is used as a sheath pipe, The pipe propulsion method such as the method of renewing the pipe line by inserting a new small pipe has been widely adopted.

  The sheath pipe propulsion method is to insert and lay a new pipe P having a smaller diameter in the existing pipe P ′ buried between the start pit S and the arrival pit R as shown in FIG. In the starting pit S, a hydraulic jack J is installed, the rear portion of the hydraulic jack J abuts against the reaction force receiver H, and the front portion presses the new pipe P via the push angle B. The new pipe P is sequentially joined by inserting the insertion port 1 at the tip end thereof into the receiving port 2 at the rear end part of the preceding new pipe P, and is pushed into the existing pipe P ′.

  In this sheath pipe propulsion method, the pipe line composed of sheath pipes (existing pipes) P ′ is usually taken from the starting anti-S so that the succeeding new pipe P reliably presses the preceding new pipe P in the connected state. It is designed so that there is no gradient or an upward gradient toward the ultimate resistance R. If the slope is downhill, the preceding new pipe P is self-propelled, which is dangerous in construction, and if both the new pipes P and P are seismic pipes such as S-shaped pipes, there is a risk that the allowance will be lost. Because.

JP-A-10-252944 Japanese Utility Model Publication No. 4-133084

  However, if there is a shortage of land at an appropriate position for the start-up anti-S, or if an ascending slope is selected, the curved portion is in the vicinity of the start-up anti-S, and many short new pipes P must be used. In some cases, the sheath of the descending slope from the anti-S is selected as the pipe P ′. In the case of this downward slope, a problem due to the self-running of the preceding new pipe P occurs.

  Conventionally, as disclosed in Patent Document 1 and the like, as shown in FIGS. 18 and 19, casters 24 are attached around the new pipe P, and the new pipe P runs smoothly (propelled) regardless of rolling. Yes. Since the caster 24 originally moves smoothly while suppressing resistance, the new pipe P is easy to move, and the above-mentioned self-running is a big problem in the down-slope sheath P '. Further, even if a sled is attached around the new pipe P described in Patent Document 2 or the like, the sled has the same purpose as the caster 24, so that self-running is a big problem.

Incidentally, as shown in FIG. 20 (a), 'when there is a _1, the curved portion P' to the starting anti-S near curved portion P must take into use the new pipe P of a length obtained through the curvature of _1, The remaining long length from the curve portion P ′ ₁ to the arrival resistance R and the inside of the pipe P ′ (distance L ₂ ) will also form a pipe line with the short new pipe P. On the other hand, as shown in FIG. 5B, if the curved portion P ′ ₁ is in the vicinity of the reaching resistance R, only a short portion (distance L ₃ ) from the curved portion P ′ ₁ to the reaching resistance R is shortened. The tube P may be used. From this point of view, it is preferable that the curve portion P ′ ₁ is as close to the ultimate resistance R as possible in terms of construction economy.

  Further, as shown in FIG. 21, the fume pipe for propulsion method mainly used as the sheath pipe P ′ has an opening b ′ on its inner surface with a cushion material c interposed at the joint b, and is being propelled. It is designed to prevent damage to the end face. For this reason, when the pipe P is propelled into the sheath pipe P ′, the caster 24 may be fitted into the opening b ′ to prevent traveling. When the pipe is propelled over a long distance, since the caster 24 passes through the sheath opening b ′ several times, the edge d of the opening b ′ is lost, as shown in FIG. The amount of depression of the caster 24 into the opening b ′ is also increased. If it falls greatly, the running performance will drop.

  This invention makes it the 1st subject to eliminate self-running of the new pipe P also in the promotion of the downward slope, and makes it the 2nd subject to eliminate the fall of a caster.

  In order to achieve the first object, the present invention sets the friction resistance against the guide sheath and the inner surface of the tube that performs the same operation as the above-described casters and warps to such an extent that the new tube does not self-run. In other words, self-running is prevented by frictional resistance.

  In order to achieve the second problem, the present invention provides a plurality of casters, and even if one caster corresponds to the sheath opening of the sheath, another caster abuts against the sheath inner surface, One caster was prevented from fitting into the opening.

  The means for achieving the second problem can be used for all propulsion methods having a seam recess in the sheath pipe regardless of the gradient, but can be used in combination with the means for achieving the first problem.

As described above, the present invention prevents the self-running of the pipe in the downhill propulsion, so that the workability is improved, and the seismic pipe such as the S-shaped pipe maintains a predetermined body interval. It can be installed in Mamasaya.
In addition, since the caster is less likely to fall into the sheath recess of the sheath, the tube can be smoothly traveled (promoted).

Main part cutting front view of one embodiment Cutaway side view of the main part of the embodiment Main part sectional view of the same embodiment The warp of the same Example is shown, (a) is a front view, (b) is a cut side view. Operational diagram of this embodiment Stretching action diagram of one embodiment Main part cutting front view of another embodiment Cutaway side view of the main part of the embodiment Main part cutting front view of another embodiment Cutaway side view of the main part of the embodiment Sectional drawing of the principal part of another Example Sectional drawing of the principal part of another Example Sectional drawing of the principal part of another Example Sectional drawing of the principal part of another Example Sectional drawing of the principal part of another Example Another embodiment is shown, (a) is a partial front view, (b) is the same operation diagram. Illustration of sheath tube propulsion method Cutaway front view of the main part of the conventional example Cutaway side view Propulsion piping diagram Action diagram of conventional example

  As an embodiment of the present invention that achieves the first problem, in the propulsion method of installing a pipe line by inserting a pipe insertion port into a receiving pipe of a preceding pipe and feeding it in a downward slope into the pipe, A guide that guides the pipe in sliding contact with the inner surface of the sheath at an appropriate position in the circumferential direction at an appropriate position in the length direction of the tube, and the friction resistance force with the sheath of the guide is such that the tube does not self-run. The following structure can be adopted.

  At this time, an annular flange is fitted to the outer surface of the insertion port, and in the sheath tube propulsion method in which thrust is transmitted from the insertion port side to the receiving side through the annular flange during propulsion, the guide is provided on the flange. it can. The flange is divided into a plurality of portions in the circumferential direction, and is formed into an annular shape by fastening the divided surfaces, and is pressed against the outer peripheral surface of the insertion port so that the flange cannot move with the above-mentioned propulsive force. It is good to do.

  As an embodiment of the present invention that achieves the second problem, in the sheath tube propulsion method in which the sheath of the tube is guided by a caster provided around the sheath of the tube, a plurality of the casters are provided in the longitudinal direction of the tube, Even if the one caster corresponds to the joint recess between the sheaths, the structure may be adopted in which the other casters are in contact with the sheath inner surface to prevent the one caster from being fitted into the joint recess.

  The embodiment for achieving the first problem and the embodiment for achieving the second problem each exhibit a sufficient effect, but can be used in combination.

  An embodiment is shown in FIGS. 1 to 6, and this embodiment has an S-shaped joint structure of a ductile cast iron pipe P, and a duct pipe P ′ embedded in the ground such as a steel pipe or a concrete pipe is ductile by a propulsion method. The pipe of the cast iron pipe P is installed, and the joint part is provided with a projection 3 at the tip of the insertion port 1 and a lock ring 5 on the inner surface of the receiving port 2, respectively, with a rubber ring 6 and a backup ring 6a interposed. After inserting the insertion port 1 into the receiving port 2, the push ring 9 is applied to the rubber ring 6 through the split ring 9 a, and the stud bolt 12 is screwed into the receiving port 2 through the push ring 9 and fastened. The rubber ring 6 is pushed in and sealed.

  An annular flange 20 is fitted on the outer periphery of the insertion port 1 outside the receiving port 2, and a propulsive force transmission material 14 is provided with a protective ring 13 interposed between the flange 20 and the stud bolt 12 (end surface of the receiving port 2). It has been. The propulsive force transmission member 14 has an annular shape, but may be divided in the circumferential direction, and may be intermittent. In short, it is sufficient to have strength against driving force.

This propulsive force transmission material 14 is a high-strength resin foam having a compressive stress of 1 to 30 kgf / cm ² (≈0.1 to 3 MPa) (expansion coefficient more than 5 times that of a single resin) and changing the expansion ratio. As a result, the elastic limit stress changes. Typical examples of these materials are polystyrene and polyurethane. Of course, other resin materials having a desired propulsive force transmission and shrinkage, hard paper such as cardboard, foam metal, and the like may be used. In addition, a resin container or the like enclosing a liquid or gas can be an effective means.

  The protection ring 13 is provided with a flange 13c at a part of the periphery, and is positioned (centered) by applying the flange 13c to the upper surface of the bolt 12. By interposing this protective ring 13, the force from the bolt 12 is transmitted to the entire contact surface of the propulsive force transmission member 14 without being concentrated. As long as this is transmitted, the ring 13 can be divided or intermittent. The ridge 13c can also be omitted.

  As shown in FIGS. 2 and 3, the flange 20 has an L-shaped section and is divided into four equal parts to form a saddle band. A fastening piece 22 is provided at both ends of the divided piece 21, and a rib 23 is provided in the middle. It has been. A caster 24 is rotatably provided between the fastening pieces 22 and 22 of the adjacent split pieces 21 and 21 of most of the flange 20, and a bolt and nut 25 is inserted through the caster 24. As a result, the flange 20 is reduced in diameter and pressed against the outer peripheral surface of the insertion port 1 (see FIG. 19).

On the other hand, a sled 30 serving as a guide shown in FIG. 4 is interposed between the fastening pieces 22 and 22 of the adjacent split pieces 21 and 21 of some flanges 20 and fastened by bolts and nuts 25. This sled 30 is made of iron and includes a base 31 and a sliding contact portion 32 between the inner surface of the sheath P 'and is provided in place of the caster 24 to increase the frictional force with the sheath P'. Is appropriately provided in each pipe P so that it does not run on a downward slope (angle: θ). For example, Wsin θ <μ ₁ W ₁ cos θ + μ ₂ W ₂ cos θ (1) is satisfied.

That is, W is the weight of the entire insertion extension tube, W _{1 is} the weight of the tube provided with a means such as a sled, and W _{2 is} the weight of the tube to which the caster is attached, and W = W ₁ + W ₂ . The force that causes the entire P to slide down is represented by W sin θ. Further, the force for stopping the slip of the pipe P is represented by W cos θ from the vertical component of the pipe weight. Further, when the friction coefficient between the pipe P provided with a means such as a warp and the like and the sheath P ′ is μ ₁ , the resistance force is F ₁ = μ ₁ W ₁ cos θ. On the other hand, when the friction coefficient of the pipe P provided with the casters 24 is μ ₂ , the resistance force is F ₂ = μ ₂ W ₂ cos θ. Therefore, in order for the pipe P not to be self-propelled, the above formula (1) needs to be satisfied, and until the condition of the formula (1) is satisfied, the number of pipes P provided with means that does not self-propell is increased. To do. The shape of the sled 30 is not limited to that shown in FIG. 4, and the position thereof may be other than the joint as shown in FIG.

  The configuration of this embodiment is as described above. In the propulsion method shown in FIG. 17, when the insertion port 1 is inserted into the receiving port 2 to join the pipes P and P, first, FIG. As shown in FIG. 2, the insertion slot 1 is inserted up to the dimension L with the specified barrel, and the protective ring 13 and the like are moved to the insertion slot 1. In this state, the rubber ring 6 and the like are loaded and the joint is joined according to a normal procedure ((b) in the figure).

  Next, the protective ring 13 is shifted to a position where it hits the head of the bolt 12, and the two-way propulsive force transmission member 14 is attached in a ring shape, and further fitted with a flange 20 to be fastened (from (c) to (d) in the figure). ). In this state, propulsion is applied with a jack. This propulsion is effective for long-distance propulsion where there is a concern about rolling, because even if rolling occurs, the pipe P can be supported by any of the casters 24 or the sled 30 and the propulsive force can be prevented from becoming excessive. . Further, even if the sheath (pipe) has a downward slope, the sheath P is provided with sufficient frictional force by the sled 30 so that the pipe P does not self-run. Absent.

  When the laying of the required length of the pipe P is completed, the mortar a is placed between the sheath pipe P 'and the new pipe P as shown in FIG. If a large pulling force is applied during an earthquake or the like, the renewal conduit moves until the insertion port 2 moves until the projection 3 abuts against the lock ring 5 as shown in FIG. In addition, if a large insertion force is applied, the propulsive force transmission member 14 contracts or collapses as shown in FIG. 5B, and the insertion port 2 is further inserted to absorb the force.

  In the above embodiment, the warp 30 is provided separately. However, as shown in FIGS. 7 and 8, the end edge 22a of the fastening piece (saddle) 22 of the flange 20 is extended outward to obtain a frictional force. can do. Further, as shown in FIGS. 9 and 10, a resin pipe protecting spacer 40 that maintains the distance between the pipe P and the sheath pipe P ′ at the time of propulsion is wound around and attached to an appropriate position of the pipe P, and the spacer 40 It is also possible to prevent the self-running of the pipe by friction with the inner surface of the sheath P '. In this case, since the friction between the concrete and the resin, the friction coefficient is slightly lower than that of the iron sled 30 and the concrete.

  Each of the above embodiments was the case of an S-type joint, but the present invention can also be adopted in the case of an SII-type joint as shown in FIGS. 11 and 12, in which case the protective ring 13 is shown in FIG. In this way, the cross-section can be U-shaped in contact with the end face of the receiving port 2. At this time, as shown in the figure, it is constituted by an annular ring 13a and a U-shaped piece 13b extending from the ring 13a to the end face of the receiving port 2 and being equidistant in the circumferential direction, or both the parts 13a and 13b are integrated. It may be a thing. This U-shaped protective ring 13 can also be adopted in the above-described S-shaped joint. Further, as shown in FIG. 13, even NS type joints can be employed in various expansion joints (seismic joints) having a detachment preventing function such as PII type joints as shown in FIG.

  Further, as disclosed in Japanese Patent Laid-Open No. 2001-27092, as shown in FIG. 15, the propulsive force transmission member 14 is omitted, and the structure in which the push ring 9 is slid for further insertion of the insertion slot 2 is also employed. Can do. This push ring structure is not limited to the SII type joint shown in the figure, and can of course be adopted for various types of expansion joints with an anti-detachment function such as the NS type joint described above.

  Further, the present invention is not limited to an expansion joint with a detachment preventing function, but an expansion joint that can move the required length within a range in which the insertion port does not come off in the axial direction, such as A-type, K-type, T-type, It can also be employed in the propulsion method for fixed joint pipes such as UF type and KF type.

  In addition, although the caster 24 and the sled 30 are on the same axis line in the embodiment, they may be spirally shifted gradually in the tube axis direction. In addition, the sliding contact surfaces (friction surfaces) of the sled 30, the saddle 22, and the spacer 40 may be subjected to an appropriate friction improving process such as a saw blade, a groove, or a high friction material.

  In each of the above-described embodiments, most of the support and guidance of the pipe P in the sheath pipe P ′ is performed by the caster 24, and the sled 30 is provided to prevent the pipe P from self-propelling in the downward slope. All can be made into a sled 30. In the case of the caster 24, the problem shown in FIG. 21 occurs. For this reason, as shown in FIG. 16 (a), the fastening piece 22 of the flange 20 is elongated in the tube axis direction to provide two or more casters 24. As shown in FIG. Even if 24 corresponds to the seam opening (recessed portion) b ′, another caster 24 abuts against the inner surface of the sheath tube P ′ so as not to drop into the opening b ′ of the one caster 24. . The configuration of the plurality of casters 24 can be adopted regardless of whether all the casters 24 that do not have the sled 30 are casters 24, or the sheath P 'is descending or ascending.

DESCRIPTION OF SYMBOLS 1 Insert port 2 Receiving port 3 Insert port protrusion 5 Lock ring 6 Rubber band for sealing 8, 14 Propulsion force transmission material 9 Push ring 13 Protective ring 20 Propulsion force transmission material support flange 24 Caster 25 Flange fastening bolt / nut 30 Sledge 40 Tube Protective spacer P New pipe P 'sheath pipe (existing pipe)
b Seam recess (opening)

Claims (1)

In the propulsion method in which the insertion port (1) of the pipe (P) is inserted into the receiving port (2) of the preceding pipe (P) and fed into the sheath pipe (P ') to install the pipe line,
A ring in which the sheath (24) is guided by a caster (24) provided around the sheath (24) of the sheath (P '), and the caster (24) is fitted on the outer surface of the insertion port (1). A plurality of the casters (24) are provided on the flange (20) before and after the pipe axis direction, and one caster (24) corresponds to the seam recess (b ') between the sheath pipes (P', P '). ) Is pushed in contact with the inner surface of the sheath tube (P ′) to prevent the one caster (24) from fitting into the seam recess (b ′).

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