JP5797975B2 - Prestressed ballast track - Google Patents

Description

  The present invention relates to a prestressed ballast track.

Conventionally, a ballast track has a structure in which a sleeper is laid on a ballast laid on a roadbed, and a rail is disposed on the sleeper.
In such a ballast track, an uplift or the like due to a train load is generated, so that the restraining force on the ballast is reduced, and the track is likely to sink.

On the other hand, for example, in Patent Document 1, a prestress member fixed to the sleeper and the roadbed is provided, and prestress is applied to the ballast between the sleeper and the roadbed by the prestress member. A prestressed ballast track that restrains the ballast is disclosed.
In addition, Patent Document 2 discloses a prestressed ballast track that provides a prestress member fixed between a rail and a roadbed and applies prestress to the ballast as described above.

Japanese Patent No. 3798210 JP 2008-291420 A

However, although the prestressed ballast orbit of Patent Documents 1 and 2 can obtain the effect of suppressing the orbital settlement by restraining the ballast, the prestress decreases with the passage of time, and as a result, the orbital settlement is suppressed. There was a problem that the effect disappeared.
That is, in the prestressed ballast track, the rigidity of the sleeper and rail restraint structure by the prestress member is too high, so if the ballast undergoes plastic deformation as the train travels, the restraint follows the plastic deformation. Cannot be continued, and the binding force to the ballast is lost.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a prestressed ballast track that can maintain the effect of suppressing track settlement over a long period of time.

In order to solve the above problems, the present invention proposes the following means.
That is, the prestressed ballast track according to the present invention is a prestressed ballast track structure in which prestress is applied to the ballast between the sleeper and the roadbed by a prestress member arranged over the roadbed and sleeper in the track. in the prestressing member has elasticity in a direction of imparting the prestress, characterized by biasing to isosamples towards the sleepers on the roadbed side.

  According to the prestressed ballast track having such a feature, the prestress member follows the plastic deformation of the ballast by its elasticity and restrains the ballast. That is, since the prestress member has a structure in which the ballast is elastically constrained between the sleeper and the roadbed, it is possible to avoid the disappearance of the prestress with respect to the ballast even when the ballast is plastically deformed.

  Further, in the prestressed ballast track according to the present invention, the prestress member is connected to a tension member having a lower end fixed to the roadbed and an upper end side of the tension member, and can be elastically displaced in the vertical direction. In addition, it is preferable to include a restraining member that presses the sleeper downward.

  By pressing the sleeper downward so that the prestress member can be elastically deformed in this manner, the ballast can be restrained while appropriately following the plastic deformation of the ballast.

  Furthermore, in the prestressed ballast track according to the present invention, it is preferable that the restraining member is a spring member disposed over at least two sleepers that are spaced apart in the extending direction of the track.

  According to this, it becomes a structure which has elasticity in the direction in which a prestress member gives prestress by the biasing force of a spring member. Therefore, the ballast can be restrained while appropriately following the plastic deformation of the ballast with a simple structure, and the installation cost and the maintenance cost can be kept low.

  Further, in the prestressed ballast raceway according to the present invention, the restraint member is disposed over at least two sleepers disposed apart from each other in the extending direction of the raceway, and the beam member An urging member interposed between each sleeper may be provided.

  According to this, it becomes a structure which has elasticity in the direction in which a prestress member gives prestress by a biasing member. Therefore, the ballast can be reliably restrained while appropriately following the plastic deformation of the ballast.

  Further, in the prestressed ballast track according to the present invention, the tension member includes a first rod material disposed on the lower side, a second rod material disposed on the upper side of the first rod material, and the first A connecting portion that connects the one rod member and the second rod member so as to be elastically displaceable in the vertical direction, and the restraining member is connected to the second rod member and extends in the extending direction of the track. You may have the beam member arrange | positioned over the at least 2 sleeper arrange | positioned spaced apart.

  According to this, since the rod itself has elasticity in the vertical direction, the prestress member has a structure having elasticity in the direction in which prestress is applied. Therefore, the ballast can be reliably restrained while appropriately following the plastic deformation of the ballast.

  Furthermore, in the prestressed ballast track according to the present invention, the lower end of the tension member is fixed to the roadbed via an anchor portion, and the anchor portion is laid on the bottom surface of a recess formed in the roadbed, It is preferable to include a plate member to which the lower end of the tension member is connected and concrete filled on the plate member in the recess.

  Thereby, since the lower end of the tension member can be reliably fixed to the roadbed, it is possible to more reliably apply the restraining force to the ballast by the prestress member. The reaction force from the sleeper transmitted to the plate member via the tension member is transmitted as an upward force to the concrete and the ballast by the plate member. Thereby, the restraint force given to a ballast can be improved.

  In the prestressed ballast track according to the present invention, the plate member is preferably a fiber reinforced plastic.

  Thereby, since the weight of this board member can be reduced compared with the case where steel materials etc. are used as a board member, for example, workability in the field where it is difficult to use a heavy machine can be improved.

  According to the prestressed ballast track of the present invention, since the prestress member elastically deforms to follow the plastic deformation of the ballast, it is possible to avoid the disappearance of the restraining force on the ballast. Therefore, the orbital settlement suppression effect can be maintained for a long time.

It is sectional drawing containing the track extension direction of the prestressed ballast track | orbit concerning 1st embodiment. It is sectional drawing orthogonal to the track extension direction of the prestressed ballast track | orbit concerning 1st embodiment. It is a partially expanded view of the prestress member in FIG. It is AA sectional drawing of FIG. It is a partial enlarged view of the prestress member in the prestressed ballast track | orbit concerning 2nd embodiment. It is AA sectional drawing of FIG. It is a partially expanded view of the prestressed member in the prestressed ballast track according to the third embodiment. It is AA sectional drawing of FIG. It is sectional drawing orthogonal to the track extension direction of the prestressed ballast track | orbit concerning a modification. It is sectional drawing orthogonal to the track extension direction of the prestressed ballast track | orbit concerning a modification. It is sectional drawing orthogonal to the track extension direction of the prestressed ballast track | orbit concerning a modification.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, a prestressed ballast track 100 according to this embodiment includes a sleeper 4 having a prism shape extending in a track width direction on a ballast 3 laid on a roadbed 1 in a track extending direction. A plurality of rails 5 are installed at intervals, and a pair of rails 5 are laid on the sleepers 4 along the track extending direction. The prestressed ballast track 100 is provided with a prestress member 10 disposed between the sleeper 4 and the roadbed 1 and an anchor portion 60 for fixing the prestressed member 10 to the roadbed 1. ing.

  As shown in FIGS. 1 to 4, the prestress member 10 includes a rod (tension member) 20 and a restraining member 30, and extends between the pair of adjacent sleepers 4 and the roadbed 1. A plurality are provided. In the present embodiment, a plurality of prestress members 10 are provided so that one prestress member 10 corresponds to a pair of adjacent sleepers 4. In other words, every other pre-stress member 10 is provided between the sleepers 4 that are arranged at intervals in the track extending direction.

The rod 20 is a rod-shaped member made of, for example, metal, carbon, or the like, and vertically extending across the roadbed 1 and the pair of sleepers 4 at the center in the track width direction at the middle position between the pair of adjacent sleepers 4. It is provided so that it may extend.
The rod 20 has a lower end fixed to the roadbed 1 via the anchor portion 60 and extends upward from the lower end so as to pass through the ballast 3. The upper end of the rod 20 is a pair of sleepers 4. It arrange | positions so that it may protrude upwards from the upper surface.

  A male screw (not shown) is formed on the outer peripheral surface on the upper end side of the rod 20, and a lock nut 21 having a female screw on the inner peripheral surface is screwed to the male screw. Thus, the lock nut 21 is fixed so as to protrude from the outer peripheral surface of the rod 20 to the outer peripheral side on the upper end side of the rod 20. The lock nut 21 is movable relative to the rod 20 in the vertical direction only when the lock nut 21 is rotated relative to the rod 20.

  The restraining member 30 is connected to the upper end side of the rod 20 and has a role of pressing the sleeper 4 downward. Specifically, as shown in FIGS. 3 and 4, the restraining member 30 includes a spring member 31. Yes. The spring member 31 has a spring constant that is displaced within a set value by the applied pressing force.

Each of the spring members 31 has a rectangular plate shape extending along a horizontal plane, and is elastically deformable so as to bend in the vertical direction. Further, at the center in the longitudinal direction of these spring members 31, holes 33 having an inner diameter larger than the outer diameter of the rod 20 are formed penetrating in the vertical direction. The holes 33 of the spring member 31 are in communication with each other in the vertical direction, and the rod 20 is inserted from the upper side to the lower side.
Thus, the lock nut 21 is in contact with the upper surface of the spring member 31, and the relative movement of the restraining member 30 made of the spring member 31 in the upward direction with respect to the rod 20 is restricted by the lock nut 21.

  Further, the restraining member 30 formed of the spring member 31 is disposed along the longitudinal direction of the spring member 31 in the track extending direction, that is, the longitudinal direction of the restraining member 30. As a result, the restraining member 30 is disposed over the upper surfaces of the pair of sleepers 4 such that both ends in the longitudinal direction are in contact with the upper surfaces of the pair of sleepers 4.

  In the present embodiment, as shown in FIG. 3, the both ends of the spring member 31 on the lower surface in the longitudinal direction, that is, the portions facing the sleepers 4 on the lower surface protrude downward in a cylindrical surface shape. A cylindrical seat 32 is provided. The pair of cylindrical seats 32 are in contact with the upper surface of the sleeper 4, that is, the restraining member 30 is in contact with the sleeper 4 through the cylindrical seat 32.

  Such a restraining member 30 of the prestress member 10 is configured such that portions on both sides in the longitudinal direction can be elastically displaced in the vertical direction with the center in the longitudinal direction of the spring member 31 serving as a connection point with the rod 20 serving as a fulcrum. That is, the prestress member 10 has a structure in which the restraint member 30 is elastically displaceable so that the prestress member 10 itself has elasticity in the vertical direction.

  Further, the restraining member 30 presses the sleeper 4 downward through a contact portion with the sleeper 4. That is, the restraining member 30 is restricted from moving upward with respect to the rod 20 by the lock nut 21, so that the restraining member 30 is located at both ends in the longitudinal direction as compared with the longitudinal center of the spring member 31 that is a connection point with the rod 20. The portion is elastically deformed upward. As a result, the sleeper 4 is pressed downward by the pressing force applied from the lock nut 21 to the restraining member 30 and the elastic force of the restraining member 30 itself.

  In order to increase the pressing force of the sleeper 4 by the restraining member 30, the lock nut 21 may be rotated and displaced downward. As a result, in addition to an increase in the pressing force applied from the lock nut 21 to the restraining member 30, an increase in the elastic force due to the elastic deformation of the portions on both ends in the longitudinal direction of the restraining member 30 further upward causes a pillow. The pressing force to the gap 4 can be increased.

  As shown in FIGS. 1 and 2, the anchor portion 60 is provided in a recess 2 formed in the roadbed 1. That is, a plurality of recesses 2 that are recessed downward are formed in the center of the upper surface of the roadbed 1 in the track width direction at intervals in the track extending direction, and an anchor portion 60 is provided in each of these recesses 2. Yes. In the present embodiment, one recess 2 is formed below the pair of sleepers 4 corresponding to one prestress member 10, that is, the recess 2 is formed immediately below the pair of sleepers 4. Yes.

  In this embodiment, the dimension of the recess 2 in the track width direction is set to be substantially the same as the dimension of the sleeper 4 in the track width direction, but the dimension of the recess 2 in the track width direction is arbitrarily set. be able to. Moreover, it is preferable that the dimension in the track extending direction of the recess 2 is set to a size that allows the pair of sleepers 4 to be accommodated within the range of the recess 2 in plan view.

  The anchor part 60 has a plate member 61 laid on the bottom surface of the recess 2. The plate member 61 is a flat plate member made of, for example, fiber reinforced plastic (FRP), and is laid at the center in the width direction of the bottom surface of the recess 2. Further, the plate member 61 is fixed to the lower end of the rod 20 of the prestress member 10.

  The rod 20 and the plate member 61 may be fixed by fitting the lower end of the rod 20 into a recess provided in the plate member 61 or formed on the outer peripheral surface of the lower end of the rod 20. The male screw may be engaged with a female screw in a concave hole formed in the plate member 61. Further, the rod 20 and the plate member 61 do not necessarily have to be fixed to each other, and the rod 20 and the plate member 61 may be connected by abutting each other.

  Further, concrete 62 is filled above the plate member 61 in the recess 2 so as to fill the entire area of the recess 2, and the rod 20 and the plate member 61 are fixed integrally to the concrete 62. In other words, in the present embodiment, the anchor portion 60 is configured by the plate member 61 laid in the recess 2 and the concrete 62 filled in the recess 2, whereby the lower end of the rod 20 is strong against the roadbed 1. It is fixed to. In addition, as the concrete 62, it is preferable to be comprised from the mixture of a crushed stone or a generating material, and a rapid hardening mortar, for example.

  In the prestressed ballast track 100 having the above-described configuration, the restraint member 30 connected to the upper end of the rod 20 fixed to the roadbed 1 via the anchor portion 60 includes the sleeper 4 that contacts the restraint member 30. Press downward. At this time, the pressing force applied from the sleeper 4 to the ballast 3 acts as a restraining force for compressing the ballast 3 in the vertical direction, and thereby prestress is applied to the ballast 3. And orbital settlement can be controlled by restraining ballast 3 by this prestress.

  Further, in the prestressed ballast track 100 of the present embodiment, the restraint member 30 in the prestress member 10 is elastically displaceable in the vertical direction, that is, the direction in which the prestress is applied. Even when plastic deformation occurs, the restraining member 30 elastically deforms following the plastic deformation.

That is, in this embodiment, even when plastic deformation occurs in the ballast 3, the elastic displacement at both ends in the longitudinal direction of the spring member 31 of the restraining member 30 is loosened, but below the sleeper 4 by the spring member 31. The pressing toward is continued.
In this way, since the prestress member 10 elastically restrains the ballast 3 between the sleeper 4 and the roadbed 1, even if the ballast 3 is plastically deformed, the disappearance of the prestress on the ballast 3 is avoided. Can do.

  Further, by adopting the spring member 31 disposed over the pair of sleepers 4 as the restraining member 30, the ballast 3 can be restrained while appropriately following the plastic deformation of the ballast 3 with a simple structure. it can. Thereby, installation cost and maintenance cost can be suppressed low.

  Furthermore, in this embodiment, since it is comprised from the plate member 61 laid in the recessed part 2 and the concrete 62 with which it filled with this plate member 61, the lower end of the rod 20 is fixed with respect to the roadbed 1 reliably. be able to.

  Further, since the plate member 61 is disposed directly below the pair of sleepers 4 on which the pressing force acts, the reaction force of the pressing force applied from the restraining member 30 to the sleepers 4 is transmitted via the rod 20 to the plate member. 61. The reaction force transmitted to the plate member 61 in this manner is applied as an upward force to the ballast 3 through the concrete 62. Thereby, the restraining force applied to the ballast 3 can be improved, that is, the prestress by the prestress member 10 can be reliably and effectively applied to the ballast 3. Therefore, the orbital settlement suppression effect can be obtained higher.

  Further, since fiber reinforced plastic is used as the material of the plate member 61 of the anchor portion 60, the weight of the plate member 61 can be reduced compared to the case of using, for example, steel, etc., and it is difficult to use heavy machinery. It is possible to improve the workability at.

  As the spring member 31, a leaf spring is preferably used. Further, a plurality of plate springs may be used as one spring member 31 by collecting them with a fastening sheet or the like.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The prestressed ballast track 100 of the present embodiment is different from the first embodiment in the configuration of the restraining member 30 in the prestress member 10.
As shown in FIGS. 5 and 6, the restraining member 30 of the second embodiment includes a beam member 41 connected to the upper end of the rod 20 and a pair of urging members 45 provided on the beam member 41. ing.

  The beam member 41 is a steel pipe that extends in the horizontal direction and has a hollow inside, and a rod insertion hole that communicates the inside and the bottom of the beam member 41 at the lower portion of the center in the extending direction. 42 is formed. The rod 20 is inserted in the rod insertion hole 42 in the vertical direction, and the lock nut 21 is fixed to the outer peripheral surface on the upper end side of the rod 20 inside the beam member 41. When the lock nut 21 abuts on the lower surface inside the beam member 41, the upward relative movement of the beam member 41 with respect to the rod 20 is restricted.

  In order to secure the workability of rotation of the lock nut 21 with respect to the rod 20, a hole that communicates the inside and the top of the beam member 41 may be formed in the upper portion of the beam member 41 in the extending direction. . The lock nut 21 can be easily rotated relative to the rod 20 by inserting a tool into the beam member 41 through the hole.

  The beam member 41 is arranged with its extending direction along the track extending direction, whereby both ends of the beam member 41 are arranged above the pair of sleepers 4 with a space therebetween. Further, biasing member insertion holes (not shown) for communicating the inside and the lower part of the beam member 41 are formed at locations in the lower part of the beam member 41 that are directly above the pair of sleepers 4.

  Further, a spring receiving guide 44 is provided on the upper surface inside the beam member 41 immediately above the biasing member insertion holes, that is, directly above the pair of sleepers 4. The spring receiving guide 44 has a cylindrical shape that protrudes downward from the upper surface inside the beam member 41, so that the beam member 41 is not exposed to the outside of the beam member 41 through the biasing member insertion hole. It is stored inside.

The urging member 45 is interposed between the beam member 41 and the sleeper 4 and has a role of pressing the sleeper 4 downward, and includes a pedestal 46, a shaft member 47, and a spring member 48. Has been. As in the first embodiment, the spring member 48 has a spring constant that is displaced within a set value by the applied pressing force.
The cradle 46 is a plate-like member that is placed on the sleeper 4 immediately below the urging member insertion hole.

The shaft member 47 extends upward from the lower end fixed to the upper surface of the cradle 46 and is inserted into the beam member 41 through the biasing member insertion hole. The upper end of the shaft member 47 is housed in the spring receiving guide 44. Are arranged to be. As a result, the shaft member 47 and the receiving base 46 fixed integrally therewith can be moved relative to the beam member 41 in the vertical direction so as to be guided by the spring receiving guide 44.
The spring member 48 is disposed coaxially with the shaft member 47 on the outer peripheral side of the shaft member 47, and has a lower end integrally fixed to the upper surface of the receiving base 46 and an upper end facing the lower side of the spring receiving guide 44. It is fixed integrally.

  In such a restraining member 30, the vertical position of the beam member 41 is determined by adjusting the relative position of the lock nut 21 with respect to the rod 20, and via the urging members 45 provided on both sides in the extending direction of the beam member 41. A pressing force acts downward of the sleeper 4. That is, the pressing force is transmitted from the spring receiving guide of the beam member 41 to the sleeper 4 via the spring member 48 that contacts the spring receiving guide 44 and the receiving base 46 that the spring member 48 contacts. At this time, the spring member 48 is in a compressed state, and the urging member 45 itself can be elastically displaced in the vertical direction in accordance with the elasticity of the spring member 48.

  Thus, in this embodiment, the urging member 45 of the restraining member 30 is configured to be elastically displaced in the vertical direction, whereby the prestress member 10 itself has a structure having elasticity in the vertical direction. There is no.

  In the prestressed ballast track 100 configured as described above, as in the first embodiment, the pressing force transmitted from the restraining member 30 of the prestress member 10 to the sleeper 4 is the restraining force that compresses the ballast 3 in the vertical direction. Acts as As a result, prestress is applied to the ballast 3. And orbital settlement can be controlled by restraining ballast 3 by this prestress.

  In the prestressed ballast track 100 of the present embodiment, the biasing member 45 of the restraining member 30 of the prestress member 10 is elastically displaceable in the direction in which prestress is applied, that is, in the vertical direction. Even when the ballast 3 is plastically deformed due to the traveling, the restraining member 30 is elastically deformed following the plastic deformation. Therefore, even when plastic deformation occurs in the ballast 3, although the compression state of the spring member 48 of the biasing member 45 in the restraining member 30 is eased, the downward pressing of the sleeper 4 is continued. .

Therefore, as in the first embodiment, since the prestress member 10 elastically restrains the ballast 3 between the sleeper 4 and the roadbed 1, even when the ballast 3 is plastically deformed, the prestress of the ballast 3 is reduced. Disappearance can be avoided.
Note that a coil spring is preferably used as the spring member 48. Further, other spring elements such as a disc spring may be used as the spring member 48.

Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The prestressed ballast track 100 of the third embodiment is different from the first and second embodiments with respect to the rod 20 and the beam member 51 that constitute the prestress member 10.

The rod 20 of the third embodiment includes a first rod material 22, a second rod material 23, and a connecting portion 70.
The first rod member 22 is a member constituting the lower end side of the rod 20, and the lower end of the first rod member 22 is fixed to the roadbed 1 via the anchor portion 60. The second rod member 23 is a member constituting the upper end side of the rod 20, and is disposed on the upper side of the first rod member 22 via the connecting portion 70. The first rod member 22 and the second rod member 23 extend in the vertical direction according to the shape of the rod 20. A lock nut 21 is fixed and integrated with the outer peripheral surface of the upper end of the second rod member 23.

The connection part 70 has the role which connects the 1st rod material 22 and the 2nd rod material 23 so that relative displacement is possible to an up-down direction.
The connecting portion 70 includes a cylindrical casing 71 that extends vertically and has a hollow interior. The casing 71 is closed at the upper end, and has a rod material insertion hole (not shown) that communicates the inside and outside of the casing 71 in the vertical direction at the lower end. In the rod material insertion hole, the upper end side of the first rod material 22 is inserted from below to above. The lower end of the second rod member 23 is firmly fixed and integrated with the upper end of the casing 71.

  In addition, the connecting portion 70 includes a nut member 73 that is fixed to the outer peripheral surface on the upper end side of the first rod member 22 in the casing 71. The outer diameter of the nut member 73 is set to be larger than the inner diameter of the rod material insertion hole, so that the nut member 73 cannot escape from the casing 71. The nut member 73 is brought into contact with the upper end and the lower end of the casing 71, so that the relative movement range in the vertical direction between the first rod member 22 and the second rod member 23 is restricted.

Further, the connecting portion 70 includes a spring member 74 interposed between the nut member 73 in the casing 71 and the lower end of the casing 71. The spring member 74 is in a compressed state with its upper end in contact with the nut member 73 and lower end in contact with the lower end of the casing 71. Thus, the first rod member 22 is urged downward with respect to the casing 71, and the second rod member 23 fixed and integrated with the casing 71 is urged downward. As in the first and second embodiments, the spring member 74 has a spring constant that is displaced within a set value by the applied pressing force.
In addition, as the spring member 74, it is preferable to employ a coil spring disposed coaxially on the outer peripheral side of the first rod 22. Further, as the spring member 74, another spring element such as a disc spring may be used.

The beam member 51 is a steel pipe that extends in the horizontal direction and has a hollow inside, and a rod insertion hole that communicates the inside and the bottom of the beam member 51 at the lower portion of the center in the extending direction. 52 is formed. The second rod member 23 is inserted in the rod insertion hole 52 in the vertical direction, and the lock nut 21 is fixed to the upper end side outer peripheral surface of the second rod member 23 inside the beam member 51. When the lock nut 21 abuts on the lower surface inside the beam member 51, the upward relative movement of the beam member 51 with respect to the second rod member 23 is restricted.
The beam member 51 presses the sleeper 4 downward while being elastically displaceable in the vertical direction in accordance with the elastic displacement of the rod 20.

  In the prestressed ballast track 100 configured as described above, when the second rod member 23 is urged downward by the connecting portion 70, the beam member 51 connected to the second rod member 23 is also urged downward. As a result, a downward pressing force is applied to the sleeper 4 in contact with the beam member 51. Thus, the pressing force transmitted to the sleeper 4 acts as a restraining force that compresses the ballast 3 in the vertical direction. As a result, prestress is applied to the ballast 3. And orbital settlement can be controlled by restraining ballast 3 by this prestress.

  In the prestressed ballast track 100 of the present embodiment, since the beam member 51 is elastically displaceable in the vertical direction according to the second rod member 23, the ballast 3 is plastically deformed by the traveling of the train. However, the beam member 51 follows the plastic deformation. Therefore, even when plastic deformation occurs in the ballast 3, although the compression state of the spring member 74 of the connecting portion 70 in the restraining member 30 is relaxed, the downward pressing of the sleeper 4 is continued.

  Therefore, as in the first and second embodiments, the prestress member 10 elastically restrains the ballast 3 between the sleeper 4 and the roadbed 1, so even if the ballast 3 is plastically deformed, Loss of prestress can be avoided.

As mentioned above, although embodiment of this invention was described in detail, unless it deviates from the technical idea of this invention, it is not limited to these, A some design change etc. are possible.
For example, as shown in FIG. 9, the dimension of the recess 2 in the track width direction may be set smaller than the interval between the pair of rails 5, for example. In this case, the plate member 61 of the anchor portion 60 is laid on the bottom surface so as to cover the entire bottom surface of the recess 2, for example.
In addition, for example, the recess 2 formed in the roadbed 1 may have an inclined surface that gradually inclines upward toward the outer side in the width direction of the track. Thereby, the concrete 62 in the recess 2 is filled so as to spread outward in the width direction of the track as it goes upward along the inclined surface of the recess 2. In this case, the reaction force applied to the plate member 61 can be applied to the ballast 3 from below through the concrete 62 over a wide range in the track width direction. Therefore, prestress based on the prestress member 10 can be applied to the ballast 3 over a wide range.

Furthermore, in the prestressed ballast track 100, as shown in FIGS. 10 and 11, for example, a soft ground improvement may be used as the anchor portion 60.
In the prestressed ballast track 100 in FIG. 10, the recess 2 is formed deeper than in the embodiment, and the rod 20 is directly fixed to the stirring and mixing pile 62 a filled in the recess 2. Yes.
Further, in the prestressed ballast track 100 of FIG. 11, the space 2a is formed inside the roadbed without forming the concave portion 2, and the rod 20 is inserted into the space 2a and the liquid injection solidified body 62b is inserted into the space 2a. Filled. That is, the rod 20 is fixed by the chemical injection solidified body 62b.
Even in these cases, the rod 20 can be reliably fixed as in the embodiment.

  Furthermore, when the roadbed 1 is a concrete roadbed such as a viaduct, a structure in which the rod 20 is raised directly from the frame may be employed.

  In the embodiment, the lock nut 21 is provided on the outer peripheral surface on the upper end side of the rod 20. However, the lock nut 21 is limited to the lock nut 21 as long as the relative movement of the restraining member 30 can be restricted at least in the upward direction. However, other members may be used.

DESCRIPTION OF SYMBOLS 1 Subbase 2 Recess 2a Space 3 Ballast 4 Sleeper 5 Rail 10 Prestress member 20 Rod (tension member)
21 Lock nut 22 First rod member 23 Second rod member 30 Restraining member 31 Spring member 32 Cylindrical seat 33 Hole 41 Beam member 42 Rod insertion hole 44 Spring receiving guide 45 Energizing member 46 Receiving base 47 Shaft member 48 Spring member 51 Beam member 52 Rod insertion hole 60 Anchor portion 61 Plate member 62 Concrete 70 Connection portion 71 Casing 73 Nut member 74 Spring member 100 Prestressed ballast track

Claims (7)

In a prestressed ballast track that applies prestress to the ballast between the sleeper and the roadbed by a prestress member arranged over the roadbed and sleeper in the track,
Said prestressing member, said prestressing resilient in a direction to impart, prestressed track ballast, wherein the biasing to isosamples towards the sleepers on the roadbed side. The prestress member is
A tension member having a lower end fixed to the roadbed;
The prestressed ballast track according to claim 1, further comprising: a restraining member connected to an upper end side of the tension member and capable of elastic displacement in the vertical direction and pressing the sleeper downward. .   The prestressed ballast track according to claim 2, wherein the restraining member is a spring member disposed over at least two of the sleepers that are spaced apart in the extending direction of the track. The restraining member is
A beam member disposed over at least two of the sleepers disposed apart from each other in the extending direction of the track;
The prestressed ballast track according to claim 2, further comprising an urging member interposed between the beam member and each sleeper. The tension member is
A first rod member disposed on the lower side;
A second rod material disposed on the upper side of the first rod material;
A connecting portion for connecting the first rod material and the second rod material so as to be elastically displaceable in the vertical direction;
The restraining member is
3. The prestressed member according to claim 2, further comprising a beam member connected to the second rod member and disposed on at least two sleepers disposed apart from each other in the extending direction of the track. -Ballast trajectory. The lower end of the tension member is fixed to the roadbed via an anchor portion,
The anchor portion is
A plate member laid on the bottom surface of the recess formed in the roadbed and connected to the lower end of the tension member;
The prestressed ballast track according to any one of claims 2 to 5, further comprising concrete filled on the plate member in the recess.   The prestressed ballast track according to claim 6, wherein the plate member is a fiber reinforced plastic.

Images