Pile platform supporting type floating track bed and construction method thereof

Abstract

The invention relates to the technical field of urban rail transit, in particular to a pile platform supporting type floating track bed and a construction method thereof. The device comprises an elastic vibration isolation device, a pile column, a bearing platform, a prefabricated track plate and a limiting device arranged on the bearing platform and used for limiting the prefabricated track plate in the horizontal direction, the bearing platform is fixed to the top of the pile column, at least part of the pile column is fixedly embedded in a foundation, and the pile column and the bearing platform are arranged in the extending direction of a steel rail at intervals; the limiting devices are fixed to the bearing platforms or integrally arranged with the bearing platforms, the two ends, in the extending direction of the steel rails, of the prefabricated track plates are erected on the two adjacent or non-adjacent bearing platforms correspondingly, and the elastic vibration isolation devices are arranged between the prefabricated track plates and the bearing platforms. The pile platform supporting type floating track bed is simple and compact in structure, easy to maintain, good in applicability, high in cost performance, safe and reliable; the construction method is easy to operate, safe and efficient, and is widely applied to vibration isolation engineering of lines outside a garage of a vehicle depot of urban rail transit and lines of a connection section of a tunnel and an elevated line.

Description

Technical Field

[0001] The invention belongs to the technical field of urban rail transit, and in particular relates to a prefabricated floating roadbed without a base structure. Background Art

[0002] In recent years, the scale of urban rail transit construction in my country has developed rapidly. At present, in the vehicle depot with roofed property, in order to avoid the vibration and noise interference of rail vehicles on the surrounding environment and property when running on the line section outside the depot, the control technology measures combining crushed stone roadbed and vibration damping pads are usually adopted, and the vibration reduction effect target is 10dB in the design. However, in practice, it has been found that such technical solutions have many shortcomings, mainly manifested in the following aspects: first, the ballast structure with full vibration damping pads on the gravel ballast needs to be piled at uniform intervals under the entire ballast structure to ensure the stability of the entire ballast structure. The number of piles is large and the cost is high; second, the lateral restraint of the gravel is insufficient, so a seamless rail structure cannot be used, and the vibration and noise during operation are large; third, during use, the vibration damping pads cannot be replaced during the window time, making maintenance difficult; fourth, tests have shown that the final vibration damping effect of the vibration damping pads and gravel ballast in a considerable number of vehicle depots is far less than the theoretical effect. The main reasons include: (1) The product quality stability of the vibration damping pads is poor; (2) The vibration damping pads are limited by their own materials and structures, and they age during use and their elastic deformation space is blocked by silt calcification and precipitation, resulting in a decrease in vibration damping performance; (3) The vibration damping pads are easily punctured and damaged by gravel, resulting in a decrease in vibration damping performance. Summary of the invention

[0003] The first object of the present invention is to overcome the above-mentioned defects and provide a pile-supported floating roadbed with efficient and stable vibration reduction effect, capable of achieving seamless small-radius curves, convenient operation and maintenance, and better economy.

[0004] The pile-supported floating ballast of the present invention is realized as follows: it includes an elastic vibration isolation device, a pile column, a cap, a prefabricated track plate, and a limiting device arranged on the cap for limiting the prefabricated track plate in the horizontal direction. The cap is fixed on the top of the pile column, the pile column is at least partially embedded in the foundation, the pile column and the cap are arranged at intervals along the extension direction of the rail, the limiting device is fixed on the cap or integrated with the cap, the two ends of the prefabricated track plate along the extension direction of the rail are respectively mounted on two adjacent or non-adjacent caps, and the elastic vibration isolation device is arranged between the prefabricated track plate and the cap.

[0005] The specific structure of the limiting device in the pile-supported floating ballast of the present invention can be varied. For example, the limiting device includes a limiting column or a limiting protrusion integrally arranged on the pedestal, or a limiting member fixedly connected to the pedestal by connecting fasteners. Of course, the plate body of the prefabricated track slab can be provided with a limiting notch or a limiting through hole corresponding to the limiting device for cooperation. In addition, an elastic buffer structure can be provided between the limiting device and the prefabricated track slab, and the elastic buffer structure includes an elastic pad or an elastic layer formed by casting and curing.

[0006] The piles and caps are independently arranged for each rail of the track line, or two rails of the same track line share a cap.

[0007] The specific structural form of the prefabricated track plate in the pile-supported floating track bed of the present invention can also be varied. In addition to the conventional plate-type prefabricated track plate, a typical example is that the prefabricated track plate is composed of a prefabricated track single plate, the prefabricated track single plate is arranged corresponding to each rail, and the two ends of the prefabricated track single plate along the extension direction of the rail are respectively mounted on two adjacent or non-adjacent caps; or, the prefabricated track plate is a prefabricated track frame plate, and the prefabricated track frame plate is prefabricated or prefabricated and assembled by integrating a prefabricated track single plate and a connecting beam, and two prefabricated track single plates in the prefabricated track frame plate are arranged corresponding to two rails of the same track line, and the two ends of the prefabricated track frame plate along the extension direction of the rail are respectively mounted on two adjacent or non-adjacent caps.

[0008] In order to avoid prestress concentration, rounded corners are set on both sides of the end of the prefabricated track single plate, or inward chamfers are set on both sides of the end. The elastic vibration isolation device in the pile-supported floating track bed of the present invention includes various types of vibration isolators such as rubber vibration damping pads, polyurethane vibration damping pads, metal-rubber composite vibration isolators, rubber vibration isolators or steel spring damping vibration isolators. In order to facilitate the limitation of the elastic vibration isolation device, the corresponding elastic vibration isolation device on the base or / and the prefabricated track plate can also be set as an isolator limiting structure for limiting the elastic vibration isolation device in the horizontal direction. The vibration isolator limiting structure includes various specific structural forms such as limiting grooves, or limiting protrusions, or limiting fastening connectors, or limiting members fixed by fasteners.

[0009] In order to adjust the height and level, a height-adjusting gasket can be arranged between the elastic vibration isolation device and the prefabricated track plate.

[0010] As a typical application scheme, the same elastic vibration isolation device can be used to simultaneously support the ends of two adjacent prefabricated track plates. Preferably, the elastic vibration isolation device includes an upper shell, a spiral steel spring and a lower shell, a damping material is arranged in the lower shell, and the spiral steel spring is partially placed in the damping material. The upper shell is respectively provided with threaded connection holes corresponding to the adjacent prefabricated track plates that it supports and cooperates with, and the prefabricated track plates are provided with assembly clearance holes and connecting screws corresponding to the threaded connection holes. The connecting screws pass through the assembly clearance holes and cooperate with the threaded connection holes to fix the prefabricated track plates and the elastic vibration isolation device.

[0011] In addition, in order to improve the integrity of the system, the pile-supported floating ballast of the present invention may also include shear hinges, through which adjacent prefabricated track plates are connected together, so that the plate ends of adjacent prefabricated track plates always maintain vertical displacement synchronization.

[0012] In order to improve the stability and safety of the system, the pile-supported floating ballast of the present invention may also include a back-pressure device, which includes a back-pressure connector, a back-pressure plate and an anchor. The anchor is fixedly arranged on the base, the lower end of the back-pressure connector is connected to the anchor, and the upper end of the back-pressure connector cooperates with the back-pressure plate to press the back-pressure plate onto the prefabricated track plate.

[0013] Taking into account the cost-effectiveness, the length of the prefabricated track slab in the present invention is preferably 2-40 times the standard spacing of the rail fasteners.

[0014] The second object of the present invention is to provide a construction method of the above pile-supported floating ballast, which comprises the following steps: S1, construction piles, caps and limit devices on the caps; S2. Place elastic vibration isolation devices on the platform according to the position coordinates; S3. Place the prefabricated track slab on the elastic vibration isolation device; S4. Fine-tune the spatial position of the prefabricated track slab according to the position coordinates; S5. Use a limit device to lock the position of the prefabricated track plate; S6. Install fasteners on the prefabricated track slabs, lay rails, and adjust the fasteners so that the rail position accuracy meets the design requirements; If there is a shear hinge, install it; If there is a back pressure device, install it; S7. Complete the construction of the floating ballast structure.

[0015] It should be noted that during construction, in step S1, the pedestal can be made by prefabrication or cast-in-place; depending on the structure of the limiting device, the limiting device on the pedestal can be prefabricated or cast-in-place as an integral part with the pedestal, or the limiting device can be prefabricated in advance and then fixedly connected to the pedestal in a cast-in-place manner, or the anchoring connection seat of the limiting device can be prefabricated or cast-in-place as an integral part with the pedestal.

[0016] During the specific construction, in a typical step S1, the process of constructing piles and caps is: digging a foundation pit, driving piles to fix the piles in the foundation pit, welding the prefabricated caps to the piles or fastening them together with fasteners, and then backfilling the earth; or adopting the following scheme, in step S1, the process of constructing piles and caps is: digging a foundation pit, driving piles to fix the piles in the foundation pit, fixing the piles with the steel cage of the cap, then setting up a formwork and using concrete to cast the cap and the piles into one, and backfilling the earth after the maintenance is completed.

[0017] Compared with the traditional technical solution of combining gravel ballast with vibration-damping pads, the pile-supported floating ballast of the present invention uses piles and caps arranged at intervals to support elastic vibration isolation devices and prefabricated floating plates. This new floating ballast structure has the following advantages: (1) piles are only set under the rails or on both sides of the rails corresponding to the caps, which greatly reduces the number of piles and construction costs; (2) It has good adaptability to geological conditions. For areas with soft soil, deep foundation piles can be driven as piles, which is safe and reliable; (3) It has a large adjustment range and can easily cope with problems such as ground subsidence. The main structure is exposed above the foundation, which makes inspection and maintenance more convenient and can be completed during the daytime; (4) The roadbed structure is more stable, a seamless line can be realized, and the vibration and noise during line operation are smaller; (5) Compared with the existing gravel roadbed, the pile-supported floating roadbed of the present invention does not require daily maintenance such as tamping, and the maintenance and repair workload is less; (6) The vibration reduction performance is more stable, which is conducive to achieving better vibration reduction effects and ensuring the realization of vibration reduction design indicators; (6) The overall construction cost of the project is lower, which can reduce costs by more than 15%, truly achieving cost reduction and efficiency improvement. The construction method of the pile-supported floating roadbed of the present invention is simple and easy to implement, with a fast construction speed and easy to ensure the quality of the project.

[0018] In summary, the pile-supported floating ballast of the present invention has a simple and compact structure, is easy to maintain, has good applicability, high cost performance, and is safe and reliable; the construction method of the pile-supported floating ballast of the present invention is simple to operate, safe and efficient, and can be widely used in line vibration isolation projects in places such as lines outside urban rail transit depots, tunnel and elevated line connection sections, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is one of the structural schematic diagrams of the pile-supported floating ballast of the present invention.

[0020] Figure 2 for Figure 1 AA section view.

[0021] Figure 3 This is the second structural schematic diagram of the pile-supported floating ballast of the present invention.

[0022] Figure 4 for Figure 3 BB section view.

[0023] Figure 5 This is the third structural schematic diagram of the pile-supported floating ballast of the present invention.

[0024] Figure 6 This is the fourth structural schematic diagram of the pile-supported floating ballast of the present invention.

[0025] Figure 7 for Figure 6 CC section view.

[0026] Figure 8 This is the fifth structural schematic diagram of the pile-supported floating ballast of the present invention.

[0027] Fig. 9 for Figure 8 DD section view.

[0028] Fig.10 This is the sixth structural schematic diagram of the pile-supported floating ballast of the present invention.

[0029] Fig.11 for Fig.10 EE section view.

[0030] Fig.12 This is the seventh structural schematic diagram of the pile-supported floating ballast of the present invention.

[0031] Fig.13 for Fig.12 FF section view.

[0032] Fig.14 This is the eighth structural schematic diagram of the pile-supported floating ballast of the present invention.

[0033] Fig.15 for Fig.14 GG section view.

[0034] Fig.16 This is the ninth structural schematic diagram of the pile-supported floating ballast of the present invention.

[0035] Fig.17 for Fig.16 HH section view. DETAILED DESCRIPTION

[0036] Embodiment 1 like Figure 1 and Figure 2 The pile-supported floating ballast of the present invention shown in the figure comprises an elastic vibration isolation device 1, which is specifically a rubber vibration-damping pad, and also comprises a pile column 2, a cap 3, a prefabricated track plate, and a limit device arranged on the cap 3 for limiting the prefabricated track plate in the horizontal direction; the cap 3 is fixed on the top of the pile column 2, and specifically, the cap 3 and the pile column 2 are butt-welded and fixed together through corresponding preset steel flanges (not specifically shown in the figure), the pile column 2 is partially embedded in the foundation 7, the pile column 2 and the cap 3 are arranged at intervals along the extension direction of the rail, and the pile column 2 and the cap 3 are independently arranged corresponding to each rail 8 of the track line; the prefabricated track plate is composed of a prefabricated track single plate 4, The prefabricated track single plate 4 is arranged corresponding to each rail 8, and the two ends of the prefabricated track single plate 4 along the extension direction of the rail 8 are respectively mounted on two adjacent pedestals 3, and the elastic vibration isolation device 1 is arranged between the prefabricated track single plate 4 and the pedestal 3; the limiting device includes an H-shaped limiting protrusion 5 integrally arranged on the pedestal 3 corresponding to the prefabricated track single plate 4, and the H-shaped limiting protrusions 5 arranged at both ends are used to cooperate to fully constrain the horizontal movement of the prefabricated track single plate 4, and an elastic buffer structure 6 is arranged between the limiting protrusion 5 and the prefabricated track single plate 4, and the elastic buffer structure 6 is specifically an elastic pad made of rubber; the rail 8 is fixed to the surface of the prefabricated track single plate 4 through a fastener system 9.

[0037] Build Figure 1 and Figure 2 When the pile-supported floating ballast of the present invention is installed, the following steps can be followed: S1, constructing piles 2 and caps 3, specifically, digging a foundation pit, driving piles to fix the piles 2 in the foundation pit, welding the prefabricated caps 3 and the piles 2 together, the limiting protrusions 5 and the caps 3 are integrated, the two are cast together during prefabrication, and backfilling the earth; S2, placing the elastic vibration isolation device 1 on the support platform 3 according to the position coordinates; S3, placing a prefabricated track plate on the elastic vibration isolation device 1, wherein the prefabricated track plate is specifically a prefabricated track single plate 4; S4. According to the position coordinates, an elastic buffer structure 6, i.e., an elastic pad, is provided between the prefabricated track single plate 4 and the limiting protrusion 5 to fine-tune the spatial position of the prefabricated track single plate 4; S5, using the limiting protrusion 5 and the elastic pad to lock the position of the prefabricated track single plate 4; S6. Install fasteners 9 on the prefabricated track slab 4, lay rails 8, and fine-tune fasteners 9 so that the position accuracy of rails 8 meets the design requirements; S7, that is, the construction of the floating ballast structure is completed.

[0038] Compared with the traditional technical solution of combining gravel ballast with vibration-damping pads, the pile-supported floating ballast of the present invention uses piles and caps arranged at intervals to support elastic vibration isolation devices and prefabricated floating plates. This new floating ballast structure has the following advantages: (1) piles are only set under the rails or on both sides of the rails corresponding to the caps, which greatly reduces the number of piles and construction costs; (2) It has good adaptability to geological conditions. For areas with soft soil, deep foundation piles can be driven as piles, which is safe and reliable; (3) It has a large adjustment range and can easily cope with problems such as ground subsidence. The main structure is exposed above the foundation, which makes inspection and maintenance more convenient and can be completed during the daytime; (4) The roadbed structure is more stable, a seamless line can be realized, and the vibration and noise during line operation are smaller; (5) Compared with the existing gravel roadbed, the pile-supported floating roadbed of the present invention does not require daily maintenance such as tamping, and the maintenance and repair workload is less; (6) The vibration reduction performance is more stable, which is conducive to achieving better vibration reduction effects and ensuring the realization of vibration reduction design indicators; (6) The overall construction cost of the project is lower, which can reduce costs by more than 15%, truly achieving cost reduction and efficiency improvement. The construction method of the pile-supported floating roadbed of the present invention is simple and easy to implement, with a fast construction speed and easy to ensure the quality of the project.

[0039] In summary, the pile-supported floating ballast of the present invention has a simple and compact structure, good applicability, high cost performance, and safety and reliability; the construction method of the pile-supported floating ballast of the present invention is simple to operate, safe and efficient, and can be widely used in line vibration isolation projects in places such as lines outside urban rail transit depots, tunnel and elevated line connection sections, etc.

[0040] It should be noted that, in this example, each cap corresponds to two piles. In actual applications, each cap may correspond to one pile, three piles or even more piles, which can be designed according to the needs of the project. In addition, there are various ways to fix the piles and the caps. In addition to welding, fasteners and other methods can also be used. Furthermore, in addition to setting elastic pads between the prefabricated track slabs and the limiting protrusions as elastic buffer structures for achieving buffering and position adjustment, elastic layers can be cast on-site using materials such as curable elastic polyurethane, which can also achieve good technical effects as elastic buffer structures. In addition, the specific types of elastic vibration isolation devices in the pile-supported floating track bed of the present invention are various. In addition to the rubber vibration isolation pads mentioned above, they can also be polyurethane vibration isolation pads, metal-rubber composite vibration isolators, rubber vibration isolators or steel spring damping vibration isolators, etc., which can be selected and used according to the actual needs of the project, and similar technical effects can be achieved. These are simple changes based on the technical principles of the present invention and are all within the protection scope required by the present invention.

[0041] In addition, it is particularly important to point out that, based on the technical principles of this example, the length of the prefabricated track slab in the present invention can be designed according to the needs of the project. In order to facilitate the arrangement of fasteners, in general, the length of the prefabricated track slab is 2-40 times the standard spacing of the rail fasteners. The current standard spacing of rail fasteners in the field of urban rail transit is 0.6mm, and the length of the prefabricated track slab is 1.2 meters, 1.8 meters, 2.4 meters..., and the longest can be 24 meters. Of course, the design of the slab length also takes into account the gap between the slabs, and the actual product size should be slightly smaller. When applied, such as Figure 1 As shown in , the prefabricated track slab is erected on two adjacent pedestals. In this case, the prefabricated track slab can be designed to be shorter, for example, it can be 1.2 meters, 1.8 meters, 2.4 meters, etc., that is, the center distance between two adjacent pedestals is generally not less than 1.2 meters. Taking into account factors such as vibration reduction effect, construction cost, and the integrity of the track bed structure, in actual applications, the typical length of the prefabricated track slab is generally 2.4 meters or longer to control the number of piles and the number of pedestals, thereby controlling the construction cost. Due to the various length combinations of prefabricated track slabs in engineering applications, it is impossible to give examples one by one. Here, only text is used for explanation, and no more drawings are provided for explanation. They are all within the protection scope required by the present invention.

[0042] Embodiment 2 like Figure 3 and Figure 4 The pile-supported floating ballast of the present invention shown in the figure is different from the first embodiment in that the pile column 2 and the cap 3 are integrated, and two rails 8 of the same track line share a cap 3, and each cap 3 is provided with two pile columns 2 for support, wherein all the pile columns 2 are embedded in the foundation 7, and the lower part of the cap 3 is embedded in the foundation 7; inward chamfers are provided on both sides of the prefabricated track single plate 4, and grooves of corresponding shapes are provided on the limiting protrusions 5 to cooperate with the prefabricated track single plate 4; in addition, the corresponding elastic vibration isolation device 1 on the prefabricated track plate composed of the prefabricated track single plate 4 is provided with a vibration isolator limiting structure for limiting the elastic vibration isolation device in the horizontal direction, and the vibration isolator limiting structure is specifically a limiting groove locally provided on the bottom surface of the prefabricated track single plate 4, and the top of the rubber vibration damping pad serving as the elastic vibration isolation device 1 is embedded in the limiting groove.

[0043] The pile-supported floating roadbed of the present invention described in this example is different from the first embodiment in that, during the construction of the pile column 2 and the cap 3 in step S1, after the pile column 2 is fixed by piling, the pile column 2 is fixedly connected to the steel cage of the cap 3, and then a formwork is set up and the cap 3 and the pile column 2 are cast into one body by concrete, and the earth is backfilled after the curing is completed; in addition, the H-shaped limiting protrusion 5 is prefabricated separately in advance, and after the cap 3 is cured, the limiting protrusion 5 is fixedly connected to the cap 3 by secondary casting on site using high-strength grouting material according to the design position coordinates. The rest of the construction process is basically the same and will not be repeated here. In the construction method described in this example, the cap is processed by on-site casting. Since the limiting protrusion 5 adopts the method of on-site secondary casting and fixed connection of prefabricated components, compared with the simultaneous on-site casting of the cap and the limiting protrusion, the difficulty of on-site construction is greatly reduced, and it is also easier to ensure the position accuracy of the limiting protrusion, and the construction efficiency and accuracy are better. Of course, although it is not the optimal solution, the present invention does not exclude casting the pedestal and the limiting protrusion on site at the same time. This construction solution can also achieve the beneficial technical effects described in the present invention and is also within the protection scope required by the present invention.

[0044] Compared with the first embodiment, in the technical solution of the pile-supported floating ballast described in this example, two rails of the same track line share a common pedestal, and each pedestal is provided with two piles for support, so the overall structure is simpler. Since the pedestal area is larger, and all the piles are embedded in the foundation, the lower part of the pedestal is also embedded in the foundation, so the stability is better, which is beneficial to improving the construction efficiency and system safety; in addition, inward chamfers are provided on both sides of the prefabricated track single plate, which can effectively avoid local stress concentration at the edges and corners of the plate body and prevent damage to the prefabricated track single plate, which is beneficial to improving the service life of the prefabricated track single plate; in addition, after a limiting groove is provided on the prefabricated track single plate corresponding to the elastic vibration isolation device, a reliable limit can be provided for the elastic vibration isolation device to prevent the elastic vibration isolation device from moving horizontally during use.

[0045] Based on the technical principles of this example, in addition to setting inward chamfers on both sides of the prefabricated track single plate, technical means such as setting rounded corners on both sides of the end of the prefabricated track single plate can also be used. This can also achieve the technical effect of preventing local stress concentration at the corners of the plate body and avoiding damage at the corners of the plate body, which is also within the protection scope required by the present invention.

[0046] Embodiment 3 like Figure 5The pile-supported floating ballast of the present invention shown in the figure is different from the second embodiment in that the limiting device is a limiting member fixedly connected to the base through connecting fasteners, and the limiting member is specifically a limiting stopper 13. An anchoring connection seat 11 is arranged on the base 3 corresponding to the limiting stopper 13, and the limiting stopper 13 is fixedly connected to the anchoring connection seat 11 by connecting fasteners 12, so as to fix the limiting device on the base 3; in addition, it also includes a height adjustment gasket 10, which is arranged between the elastic vibration isolation device 1 and the prefabricated track single plate 4.

[0047] Compared with the second embodiment, the limiting device is changed into a limiting block which can be separated from the base, the structure of the base is simpler, the fixed connection operation between the base and the limiting structure is easier to achieve, and the position adjustment is more convenient; due to the addition of height adjustment gaskets, each prefabricated track single plate can be independently and accurately adjusted in height and leveling, which is very convenient.

[0048] In addition, compared with the second embodiment, during the construction of the pile-supported floating ballast of the present invention described in this embodiment, in step S1, the anchor connection seat 11 of the limiting device is cast into one piece with the pedestal 3, and then the connecting fastener 12 is used to cooperate with the anchor connection seat 11, and the limiting block 13 is pre-installed on the pedestal 3, so that a rough limit can be provided when the prefabricated track veneer is placed. After the spatial position of the prefabricated track veneer 4 is finely adjusted by the height adjustment gasket 10 in step S4, in step S5, the relative position of the limiting block 13 and the anchor connection seat 11 is locked by the connecting fastener 12, and the limiting device is fixed on the pedestal, and the position of the prefabricated track veneer 4 is also locked. The remaining operations are basically the same and will not be repeated here. It should be particularly pointed out that if the pedestal is made in a prefabricated manner in step S1, and the limiting device uses a limiting block that can be detached from the pedestal, the structure of the pedestal is simpler, the appearance is more standardized, and its construction, transportation, and storage are more convenient.

[0049] Embodiment 4 like Figure 6 and Figure 7The pile-supported floating ballast of the present invention shown in the figure is different from the third embodiment in that the two ends of the prefabricated track single plate 4 along the extension direction of the rail are erected on two non-adjacent pedestals 3 separated by a pedestal in the middle, that is, there are three pedestals 3 under each prefabricated track single plate 4 to cooperate with it, and each pedestal 3 is respectively provided with an elastic vibration isolation device 1 to elastically support the prefabricated track single plate; in addition, the limiting device is composed of a limiting protrusion 5 integrated with the pedestal 3 and a detachable limiting stopper 13, and the limiting protrusion 5 and the limiting stopper 13 are respectively correspondingly arranged on both sides of the plate end of the prefabricated track single plate 4, wherein the limiting stopper 13 is fixedly connected to the anchor connection seat 11 by a connecting fastener 12, and the limiting stopper 13 and the prefabricated track single plate 4 are connected. , an elastic layer is cast on-site using curable elastic polyurethane material in the gaps between the limiting protrusions 5 and the prefabricated track single plate 4 and between the plate ends of adjacent prefabricated track single plates 4 as an elastic buffer structure 6; in addition, the elastic vibration isolation device 1 is specifically a rubber vibration isolator, and the vibration isolator limiting structure is specifically a limiting groove provided on the prefabricated track single plate 4 and the base 3 respectively corresponding to the elastic vibration isolation device 1, and the top and bottom of the elastic vibration isolation device are respectively embedded in the limiting grooves. In order to prevent water accumulation, the top surface of the base on the inner side of the two limiting protrusions 5 is higher than the top surface of the base on the outer side of the limiting protrusions 5, and the bottom surface of the limiting groove is also not lower than the base surface on the outer side of the limiting protrusion 5, and the limiting groove is at least partially kept open along the extension direction of the rail to facilitate drainage.

[0050] Compared with Example 3, since in the technical scheme described in this example, the two ends of the prefabricated track single plate are erected on two non-adjacent pedestals along the extension direction of the rails and cooperate with three pedestals at the same time, the size of a single prefabricated track single plate can be longer and the weight can be heavier, which is beneficial to improving the vibration reduction effect and improving the construction efficiency. Of course, based on this technical principle, in actual engineering applications, the prefabricated track single plate can also span two or more pedestals, that is, it can be used in conjunction with four or more pedestals at the same time, which is also within the protection scope required by the present invention; limiting grooves are respectively provided on the prefabricated track single plate and the pedestal corresponding to the elastic vibration isolation device, which has a better horizontal limiting effect on the elastic vibration isolation device; the elastic layer is cast on-site using a curable elastic polyurethane material as an elastic buffer structure, which has better adaptability to gap asymmetry, tighter cooperation, and is safer and more reliable.

[0051] Compared with the third embodiment, in the construction process of the pile-supported floating ballast of the present invention described in this embodiment, in step S6, the limit stopper 13 is fixedly connected to the anchor connection seat 11 by the connection fastener 12, the limit device is fixed on the cap, and then the elastic layer is cast on site as the elastic buffer structure 6 using elastic polyurethane material in the gaps between the limit stopper 13 and the prefabricated track single plate 4, between the limiter 5 and the prefabricated track single plate 4, and between the plate ends of adjacent prefabricated track single plates 4, so as to lock the position of the prefabricated track single plate 4. The remaining steps are basically the same and will not be repeated here.

[0052] It should be particularly noted that, based on the technical principles described in this example and the aforementioned embodiments of the present invention, the length of the prefabricated track slab in the present invention can be designed according to engineering needs. In order to facilitate the arrangement of fasteners, in general, the length of the prefabricated track slab is 2-40 times the standard spacing of the rail fasteners. The current standard spacing of rail fasteners in the field of urban rail transit is 0.6 mm. The length of the prefabricated track slab is 1.2 meters, 1.8 meters, 2.4 meters..., and the longest can be 24 meters. Of course, the design of the slab length also takes into account the gap between the slabs, and the size of the actual product should be slightly smaller. When applied, such as Figure 1 As shown in , the prefabricated track slab is erected on two adjacent pedestals. In this case, the prefabricated track slab can be designed to be shorter, for example, it can be 1.2 meters, 1.8 meters, 2.4 meters, etc., that is, the center distance between two adjacent pedestals is generally not less than 1.2 meters; based on this principle, the prefabricated track slab in this example is coordinated with three pedestals, and the length of the prefabricated track slab should be controlled at 2.4 meters or more. Taking into account the vibration reduction effect, construction cost, integrity of the track bed structure and other factors, in actual applications, the typical length of the prefabricated track slab is generally 2.4 meters or more to control the number of piles and the number of pedestals, and thus control the construction cost. Since the length combination of the prefabricated track slab can be varied in engineering applications, it is only described in text here, and no longer illustrated one by one, all of which are within the protection scope required by the present invention. The above description is also applicable to other embodiments of the present invention, which are described here together and will not be repeated later.

[0053] Embodiment 5 like Figure 8 and Fig. 9 The pile-supported floating ballast of the present invention shown in the figure is different from the fourth embodiment in that the prefabricated track plate is a prefabricated track frame plate 24, which is prefabricated by integrating a prefabricated track single plate and a connecting beam. Two prefabricated track single plates in the prefabricated track frame plate 24 correspond to two rails of the same track line, and the two ends of the prefabricated track frame plate along the extension direction of the rails are respectively mounted on two adjacent pedestals 3; the limiting device is a limiting column 14 integrated in the middle of the pedestal 3, and the prefabricated track frame plate 24 is prefabricated by integrating a prefabricated track single plate and a connecting beam. A limiting notch is arranged on the connecting beam to cooperate with the limiting column 14, and an elastic layer formed by casting and curing is arranged between the limiting notch and the limiting column as an elastic buffer structure 6; in addition, in order to improve the integrity, it also includes a shear hinge, which is specifically a side shear plate 15. The side shear plates 15 are respectively fixed to the ends of adjacent prefabricated track frame plates 24 by anchoring connecting bolts 16, and the adjacent prefabricated track frame plates 24 are connected together by the shear hinge, so that the plate ends of the adjacent prefabricated track frame plates 24 always maintain vertical displacement synchronization.

[0054] Compared with the fourth embodiment, due to the use of prefabricated track frame plates, the technical solution described in this example has better integrity of the prefabricated track plates and the roadbed structure, and the construction is faster and more efficient. In particular, after the prefabricated track frame plates are connected by shear hinges, the roadbed structure has stronger integrity, which is conducive to further improving the vibration reduction effect and system stability, and is safer and more reliable. In addition, the limiting columns can be used to simultaneously achieve reliable limitation of the prefabricated track frame plates in the transverse and longitudinal directions of the rails, and the overall structure is simpler. In addition, in this example, the top surface height of the pedestal 3 is generally higher than the surface of the foundation 7, and the bottom surface height of the limiting groove on the pedestal 3 is not lower than the surface of the foundation 7. The side walls around the limiting groove are also provided with open notches, which can effectively prevent water accumulation from affecting the vibration reduction effect.

[0055] The pile-supported floating ballast of the present invention described in this example can be constructed according to the following steps: S1, construct pile column 2 and cap 3, specifically, pile column 2 is fixed by piling, pile column 2 is fixedly connected with the steel cage of cap 3, formwork is set up and cap 3 and pile column 2 are cast into one body by concrete, and earthwork is backfilled after curing, wherein limit column 14 and cap 3 are cast into shape synchronously and integrally; S2, placing the elastic vibration isolation device 1 on the support platform 3 according to the position coordinates; S3, placing the prefabricated track plate on the elastic vibration isolation device 1, wherein the prefabricated track plate is specifically a prefabricated track frame plate 24; S4, fine-adjusting the spatial position of the prefabricated track frame plate 24 using the height-adjusting gasket 10 according to the position coordinates; S5, casting a curable elastic layer between the limiting notch on the prefabricated track frame plate 24 and the limiting column 14 to form an elastic buffer structure 6, locking the position of the prefabricated track frame plate 24; S6. Install fasteners 9 on the prefabricated track frame plate 24, lay rails 8, and adjust fasteners 9 so that the position accuracy of rails 8 meets the design requirements; Install shear hinges, and use anchor bolts 16 to fix the side shear plates 15 to the ends of adjacent prefabricated track frame plates 24, so as to connect the adjacent prefabricated track frame plates 24 together through the shear hinges; S7, that is, the construction of the floating ballast structure is completed.

[0056] It should be noted that, in the present example, the use of shear hinges is described by taking the side-mounted shear plate as an example. In actual applications, the present invention can adopt various shear hinges. In addition to the side-mounted shear hinges, it can also be an upper-mounted shear hinge, a clamping shear hinge or a center-mounted shear hinge, etc.; in addition, the prefabricated track frame plate can be prefabricated and assembled from a single prefabricated track plate and a connecting beam in addition to being prefabricated as an integrated whole; in addition, in engineering, the prefabricated track frame plate can be erected on two adjacent pedestals as well as on two non-adjacent pedestals (that is, the prefabricated track frame plate is used in conjunction with three or even more pedestals at the same time). These are all simple changes based on the technical principles of the present invention, and can also achieve good technical effects, and are all within the protection scope required by the present invention.

[0057] Embodiment 6 like Fig.10 and Fig.11 The pile-supported floating ballast of the present invention shown in the figure is different from the fifth embodiment in that the elastic vibration isolation device is specifically a steel spring damping vibration isolator, which simultaneously supports the ends of two adjacent prefabricated track frame plates 24. The steel spring damping vibration isolator comprises an upper shell 20, a spiral steel spring 21 and a lower shell 19. A damping material 22 is arranged in the lower shell 19, and a part of the spiral steel spring 21 is placed in the damping material 22. The upper shell is respectively provided with threaded connection holes corresponding to the adjacent prefabricated track frame plates 24 supported and matched therewith, and a connecting pipe rack 17 is provided on the prefabricated track frame plate 24 corresponding to the threaded connection holes. An assembly clearance hole and a connecting screw 18 are provided on the connecting pipe rack 17. The connecting screw 18 passes through the assembly clearance hole and cooperates with the threaded connection hole to fix the prefabricated track frame plate 24 with the steel spring damping vibration isolator. Four connecting screws 18 are correspondingly arranged on each steel spring damping vibration isolator.

[0058] Compared with the fifth embodiment, in the technical solution described in this embodiment, since the steel spring damping isolator is used as the elastic vibration isolation device, it can achieve a better vibration reduction effect, and the vibration reduction performance of the track bed system is greatly improved; in addition, since the steel spring damping isolator simultaneously supports the ends of two adjacent prefabricated track frame plates, and the prefabricated track frame plate 24 is fixedly connected to the steel spring damping isolator by using the connecting screw 18, on the one hand, the number of elastic vibration isolation devices involved in the track bed system is less, which is conducive to improving the installation and construction efficiency; on the other hand, in this track bed system, the upper shell 20 of the steel spring damping isolator cooperates with the connecting screw 18 and is simultaneously connected The upper shell 20 of the two adjacent prefabricated track frame plates 24 actually also plays the role of a shear hinge. By designing and calculating and controlling the thickness and strength of the steel plate of the upper shell 20, the shear force transmission between the adjacent prefabricated track frame plates during the operation of the rail vehicle can be smoothly realized through the steel spring damping isolator, without the need to set up an additional shear hinge. In addition, since the upper shell 20 is at the bottom of the prefabricated track frame plate 24, its load-bearing point is very low, and the force on the plate body of the prefabricated track frame plate 24 is more reasonable, which can effectively prevent the prefabricated track frame plate from local fatigue damage, which is conducive to simplifying the structure of the track bed system, improving the service life of the track bed system, and reducing the workload of later maintenance. During the construction process, compared with the steps described in Example 5, the technical solution described in this example no longer sets up an additional shear hinge. Therefore, in step S5, the connecting screw 18 is used to pass through the assembly clearance hole and the threaded connection hole to fix the prefabricated track frame plate 24 to the steel spring damping isolator to lock the position of the prefabricated track frame plate 24. The rest of the construction process is roughly the same and will not be repeated here.

[0059] In this case Fig.10 In the example, four connecting screws are arranged corresponding to each steel spring damping isolator to cooperate with threaded connection holes to fix the prefabricated track frame plate and the steel spring damping isolator. In practical applications, the number of connecting screws can also be two, six or even more, which can be designed and selected according to the needs of the project. In addition, the damping material in the steel spring damping isolator can be a solid damping material or a liquid damping material, which can also be designed and selected according to the needs of the project.

[0060] Embodiment 7 like Fig.12 and Fig.13The pile-supported floating ballast of the present invention shown in the figure is different from the sixth embodiment in that the prefabricated track plate adopts a conventional solid prefabricated track plate 25; in addition, the limiting grooves provided on the prefabricated track plate 25 are also kept open laterally to the outside along the rail, and the steel spring damping vibration isolator can be pushed inward from the outside of the prefabricated track plate along the limiting grooves during assembly, and the two adjacent prefabricated track plates 25 supported are respectively height-adjusted and leveled by using the height-adjusting gasket 10, and then the prefabricated track plate 25 is fixedly connected to the steel spring damping vibration isolator by using the connecting screw 18 and the threaded connecting hole provided on the upper shell 20, wherein each steel spring damping vibration isolator is correspondingly provided with two connecting screws 18; in addition, in this example, the upper surface of the cap 3 The vibration isolator limiting structure is a limiting fastening connector, which is specifically an anchor bolt 23. After the prefabricated track plate 25 is fixedly connected to the steel spring damping vibration isolator, the anchor bolt 23 is used to fix the lower shell 19 of the steel spring damping vibration isolator to the base 3; furthermore, the limiting device includes two limiting columns 14 arranged on the base 3 corresponding to two adjacent prefabricated track plates, the limiting columns 14 are integrated with the base 3, and limiting through holes are arranged on the prefabricated track plate 25 corresponding to the limiting columns 14, and the cast and cured elastic layer is respectively arranged in the gap between the limiting columns 14 and the limiting through holes as an elastic buffer structure 6; fifthly, a bare hole 26 that passes through from top to bottom is arranged on the prefabricated track plate 25 as an assembly clearance hole.

[0061] Compared with the sixth embodiment, in the technical solution described in this example, since the lower shell 19 of the steel spring damping isolator is fixedly connected to the base 3, on the one hand, there is no need to set additional limiting grooves on the base, and the structure of the base can be simpler and more convenient to process; on the other hand, during maintenance, the steel spring damping isolator can be dragged out by removing the connecting screw 18 and loosening the anchor bolt 23, and then pushed back in and connected and fixed after maintenance, which is very convenient. In addition, since the prefabricated track plate in this example adopts a conventional prefabricated track plate, its integrity and structural strength are better, and the vibration mass is larger, which is conducive to achieving a better vibration reduction effect. In addition, in this example, the naked hole 26 is used as the assembly clearance hole, so there are fewer components involved and the structure is simpler.

[0062] The difference between the pile-supported floating ballast of the present invention described in this example and the sixth embodiment is that in step S5, an operation of fixing the lower shell 19 of the steel spring damping isolator to the pedestal 3 with the anchor bolts 23 is added, and the rest is basically the same and will not be described again. In addition, in this example, independent limit columns and limit through holes are used to limit each prefabricated track plate, and the horizontal limit effect is more reliable.

[0063] It should be pointed out that, based on the technical principles of this example and the aforementioned embodiments, the specific forms of the vibration isolator limiting structures arranged on the base and / or the prefabricated track plate in the present invention can be various, which can be specific structures such as limiting grooves, limiting protrusions, limiting fastening connectors or limiting members fixed by fasteners, all of which can achieve the technical effect of limiting the elastic vibration isolation device in the horizontal direction, and can all be used in the present invention. They are explained here in text and no longer illustrated one by one. They are all within the protection scope required by the present invention.

[0064] Embodiment 8 like Fig.14 and Fig.15 The pile-supported floating ballast of the present invention shown in the figure is different from the sixth embodiment in that it also includes a back-pressure device, which includes a back-pressure connector 27, a back-pressure plate 28 and an anchor 29. The anchor 29 is fixedly arranged on the base 3. The lower end of the back-pressure connector 27 and the anchor 29 are connected to each other through a threaded structure. The upper end of the back-pressure connector 27 cooperates with the back-pressure plate 28 to press the back-pressure plate 28 against the top surface of the prefabricated track frame plate 24.

[0065] During construction, the pile-supported floating ballast of the present invention can be operated according to the following steps: S1, construct pile column 2 and cap 3, specifically, pile column 2 is fixed by piling, pile column 2 is fixedly connected with the steel cage of cap 3, formwork is set up and cap 3 and pile column 2 are cast into one body by concrete, and earthwork is backfilled after curing, wherein limit column 14 and cap 3 are cast into shape synchronously and integrally; S2, placing the elastic vibration isolation device 1 on the support platform 3 according to the position coordinates; S3, placing the prefabricated track plate on the elastic vibration isolation device 1, wherein the prefabricated track plate is specifically a prefabricated track frame plate 24; S4, fine-adjusting the spatial position of the prefabricated track frame plate 24 using the height-adjusting gasket 10 according to the position coordinates; S5. Use the connecting screw 18 to pass through the assembly clearance hole and the threaded connection hole to fix the prefabricated track frame plate 24 and the steel spring damping isolator, and cast a curable elastic layer between the limiting notch on the prefabricated track frame plate 24 and the limiting column 14 to form an elastic buffer structure 6, and lock the position of the prefabricated track frame plate 24; S6. Install fasteners 9 on the prefabricated track frame plate 24, lay rails 8, and adjust fasteners 9 so that the position accuracy of rails 8 meets the design requirements; Install the back pressure device, use the back pressure connector 27 to cooperate with the anchor 29 to press the back pressure plate 28 against the top surface of the prefabricated track frame plate 24; S7, that is, the construction of the floating ballast structure is completed.

[0066] Compared with the sixth embodiment, in the technical solution described in this example, due to the addition of a back-pressure device, the warping of the prefabricated track plate along the vertical direction of the rail is effectively constrained without affecting the vibration isolation performance of the ballast bed structure. When the rail vehicle is running, the load is transferred from one end of the prefabricated track plate to the other end, and the displacement change of the prefabricated track plate in the vertical direction of the rail is small, which can effectively prevent the elastic elements in the elastic vibration isolation device from bouncing and tipping due to pressure changes, and the entire ballast bed system is more stable, safer and more reliable. Of course, in this example, four back-pressure devices corresponding to the four corners of a prefabricated track plate are used as an example for explanation. In actual applications, more back-pressure devices can also be set. In engineering applications, they can be designed and used according to the actual needs of the project. In order to balance the force, in general, the back-pressure devices at each end of the prefabricated track plate are preferably set symmetrically. This is only explained in text here, and no additional drawings are provided. It is also within the protection scope required by the present invention.

[0067] Embodiment 9 like Fig.16 and Fig.17 The pile-supported floating ballast of the present invention shown in the figure is different from the fifth embodiment in that the prefabricated track plate adopts a conventional solid prefabricated track plate 25; in addition, it also includes a back-pressure device, which includes a back-pressure connector 27, a back-pressure plate 28 and an anchor 29. The anchor 29 is fixedly arranged on the base 3. The lower end of the back-pressure connector 27 and the anchor 29 are connected to each other through a threaded structure. The upper end of the back-pressure connector 27 cooperates with the back-pressure plate 28 to press the back-pressure plate 28 against the top surface of the prefabricated track plate 25.

[0068] Compared with the construction method of the fifth embodiment, the pile-supported floating ballast of the present invention described in this embodiment can be constructed according to the following steps: S1, construct pile column 2 and cap 3, specifically, pile column 2 is fixed by piling, pile column 2 is fixedly connected with the steel cage of cap 3, formwork is set up and cap 3 and pile column 2 are cast into one body by concrete, and earthwork is backfilled after curing, wherein limit column 14 and cap 3 are cast into shape synchronously and integrally; S2, placing the elastic vibration isolation device 1 on the support platform 3 according to the position coordinates; S3, placing a prefabricated track plate on the elastic vibration isolation device 1, wherein the prefabricated track plate is specifically a prefabricated track plate 25; S4. According to the position coordinates, the spatial position of the prefabricated track plate 25 is finely adjusted using the height adjustment gasket 10; S5, pouring a curable elastic layer between the limiting notch on the prefabricated track plate 25 and the limiting column 14 to form an elastic buffer structure 6, locking the position of the prefabricated track plate 25; S6. Install fasteners 9 on the prefabricated track slab 25, lay rails 8, and adjust fasteners 9 so that the position accuracy of rails 8 meets the design requirements; Install shear hinges, and use anchor bolts 16 to fix the side shear plates 15 to the ends of adjacent prefabricated track plates 25, so as to connect the adjacent prefabricated track plates 25 together through the shear hinges; Install the back pressure device, use the back pressure connector 27 to cooperate with the anchor 29 to press the back pressure plate 28 against the top surface of the prefabricated track plate 25; S7, that is, the construction of the floating ballast structure is completed.

[0069] Compared with the fifth embodiment, in the technical solution described in this example, the prefabricated track plate in this example adopts a conventional prefabricated track plate, which has better integrity and structural strength, larger vibration mass, and is conducive to achieving better vibration reduction effect; in addition, due to the addition of a back pressure device, the prefabricated track plate is effectively constrained from tilting vertically along the rail without affecting the vibration isolation performance of the roadbed structure. During the travel of the rail vehicle, in the process of transferring the load from one end of the prefabricated track plate to the other end, the displacement change of the prefabricated track plate in the vertical direction of the rail is small, which can effectively prevent the elastic element in the elastic vibration isolation device from bouncing and tipping due to pressure changes, and the entire roadbed system is more stable, safer and more reliable. Of course, in this example, four back pressure devices are set at the four corners of a prefabricated track plate as an example for explanation. In actual applications, more back pressure devices can also be set. In engineering applications, they can be designed and used according to the actual needs of the project. In order to balance the force, in general, the back pressure devices at each end of the prefabricated track plate are preferably set symmetrically. This is only described in words, and no additional drawings are provided. It is also within the protection scope required by the present invention.

[0070] The embodiments of the present invention are only for better illustrating the technical solutions of the present invention and should not be regarded as limitations of the present invention. The technical features in many embodiments may also be used interchangeably. Based on the technical principles of the present invention, those skilled in the art may re-combine the technical solutions described in the above embodiments or simply replace some of the components therein with similar technologies. As long as they are based on the technical principles of the present invention, they are all within the protection scope required by the present invention.

Claims

1. A pile-supported floating ballast, comprising an elastic vibration isolation device, characterized in that: It also includes piles, caps, prefabricated track plates and a limiting device arranged on the cap for limiting the prefabricated track plates in the horizontal direction. The cap is fixed on the top of the pile, and the pile is at least partially embedded in the foundation. The pile and the cap are arranged at intervals along the extension direction of the rails. The limiting device is fixed on the cap or integrated with the cap. The two ends of the prefabricated track plates along the extension direction of the rails are respectively mounted on two adjacent or non-adjacent caps, and an elastic vibration isolation device is arranged between the prefabricated track plates and the cap.

2. The pile-supported floating ballast according to claim 1, characterized in that: The limiting device includes a limiting column or a limiting protrusion integrally arranged on the supporting platform, or a limiting member fixedly connected to the supporting platform through a connecting fastener.

3. The pile-supported floating ballast as claimed in claim 2, characterized in that: The plate body of the prefabricated track plate is provided with a limiting notch or a limiting through hole corresponding to the limiting device.

4. The pile-supported floating ballast as claimed in claim 2, characterized in that: An elastic buffer structure is arranged between the limiting device and the prefabricated track plate, and the elastic buffer structure includes an elastic pad or an elastic layer formed by casting and curing.

5. The pile-supported floating ballast as claimed in claim 1, characterized in that: The piles and caps are independently arranged for each rail of the track line, or two rails of the same track line share a cap.

6. The pile-supported floating ballast as claimed in claim 5, characterized in that: The prefabricated track plate is composed of a prefabricated track single plate, which is arranged corresponding to each rail, and the two ends of the prefabricated track single plate along the extension direction of the rail are respectively erected on two adjacent or non-adjacent bearing platforms.

7. The pile-supported floating ballast as claimed in claim 5, characterized in that: The prefabricated track plate is a prefabricated track frame plate, which is prefabricated or prefabricated and assembled from a prefabricated track single plate and a connecting beam. Two prefabricated track single plates in the prefabricated track frame plate correspond to two rails of the same track line, and the two ends of the prefabricated track frame plate along the extension direction of the rails are respectively mounted on two adjacent or non-adjacent pedestals.

8. The pile-supported floating ballast according to claim 6 or 7, characterized in that: Rounded corners are arranged on both sides of the end of the prefabricated track single plate, or inward chamfers are arranged on both sides of the end.

9. The pile-supported floating ballast as claimed in claim 1, characterized in that: The elastic vibration isolation device includes a rubber vibration-damping pad, a polyurethane vibration-damping pad, a metal-rubber composite vibration isolator, a rubber vibration isolator or a steel spring damping vibration isolator.

10. The pile-supported floating ballast as claimed in claim 1, characterized in that: The corresponding elastic vibration isolation device on the support platform and / or the prefabricated track plate is configured as an isolator limiting structure for limiting the elastic vibration isolation device in the horizontal direction, and the isolator limiting structure includes a limiting groove, or a limiting protrusion, or a limiting fastening connector, or a limiting member fixed by a fastener.

11. The pile-supported floating ballast according to claim 1, characterized in that: A height-adjusting gasket is arranged between the elastic vibration isolation device and the prefabricated track plate.

12. The pile-supported floating ballast as claimed in claim 1, characterized in that: The elastic vibration isolation device simultaneously supports the ends of two adjacent prefabricated track plates.

13. The pile-supported floating ballast as claimed in claim 12, characterized in that: The elastic vibration isolation device comprises an upper shell, a spiral steel spring and a lower shell. Damping material is arranged in the lower shell, and the spiral steel spring is partially placed in the damping material. The upper shell is respectively provided with threaded connection holes corresponding to the adjacent prefabricated track plates supported and matched by it. Assembly clearance holes and connecting screws are arranged on the prefabricated track plates corresponding to the threaded connection holes. The connecting screws pass through the assembly clearance holes and cooperate with the threaded connection holes to fix the prefabricated track plates and the elastic vibration isolation device.

14. The pile-supported floating ballast as claimed in claim 1, characterized in that: The pile-supported floating ballast also includes a shear hinge, through which adjacent prefabricated track plates are connected together, so that the plate ends of the adjacent prefabricated track plates always maintain vertical displacement synchronization.

15. The pile-supported floating ballast as claimed in claim 1, characterized in that: The pile-supported floating ballast bed also includes a back-pressure device, which includes a back-pressure connector, a back-pressure plate and an anchor. The anchor is fixedly arranged on the base, the lower end of the back-pressure connector is connected to the anchor, and the upper end of the back-pressure connector cooperates with the back-pressure plate to press the back-pressure plate onto the prefabricated track plate.

16. The pile-supported floating ballast as claimed in claim 1, characterized in that: The length of the prefabricated track plate is 2-40 times the standard spacing of the rail fasteners.

17. A method for constructing a pile-supported floating ballast, using the pile-supported floating ballast as claimed in any one of claims 1 to 16, characterized in that: The steps include: S1, construction piles, caps and limit devices on the caps; S2. Place elastic vibration isolation devices on the platform according to the position coordinates; S3. Place the prefabricated track slab on the elastic vibration isolation device; S4. Fine-tune the spatial position of the prefabricated track slab according to the position coordinates; S5. Use a limit device to lock the position of the prefabricated track plate; S6. Install fasteners on the prefabricated track slabs, lay rails, and adjust the fasteners so that the rail position accuracy meets the design requirements; If there is a shear hinge, install it; If there is a back pressure device, install it; S7. Complete the construction of the floating ballast structure.

18. The construction method of pile-supported floating ballast as claimed in claim 17, characterized in that: In step S1, the pedestal is made by prefabrication or cast-in-place; accordingly, the limiting device on the pedestal is prefabricated or cast-in-place as an integral part with the pedestal, or the limiting device is prefabricated in advance and then fixedly connected to the pedestal by cast-in-place, or the anchoring connection seat of the limiting device is prefabricated or cast-in-place as an integral part with the pedestal.

19. The construction method of pile-supported floating ballast as claimed in claim 17, characterized in that: In step S1, the process of constructing piles and caps is: digging a foundation pit, driving piles to fix the piles in the foundation pit, welding the prefabricated caps to the piles or fastening them together with fasteners, and then backfilling the earth.

20. The construction method of pile-supported floating ballast as claimed in claim 17, characterized in that: In step S1, the process of constructing piles and caps is: digging a foundation pit, driving piles to fix the piles in the foundation pit, fixing the piles with the steel cage of the cap, setting up a formwork and using concrete to cast the cap and the piles into one, and backfilling the earth after the maintenance is completed.

Images