Prefabricated track structure with inter-plate limiting function and curve section plate distribution method of prefabricated track structure

Abstract

The invention discloses a prefabricated track structure with inter-plate limiting and a curved section plate distribution method thereof. The track structure comprises prefabricated unit plates, a filling adjustment layer, an isolation layer and a concrete base from top to bottom. Wherein each prefabricated unit plate is of a prefabricated structure, a convex limiting structure is arranged between every two adjacent prefabricated unit plates, and the convex limiting structures are formed through cast-in-place; the center point of the prefabricated unit plate rail bearing table is located on the center line of a rail line. According to the prefabricated track structure with the inter-plate limiting function, the transverse and longitudinal stability of the prefabricated unit plates in the operation process can be guaranteed through the cast-in-place convex limiting structures, the train operation safety is guaranteed, it can be guaranteed that the convex limiting structures and the prefabricated unit plates are tightly attached, and the stability of the prefabricated unit plates is guaranteed. The method has the advantages of being high in field construction adjusting capacity and fast in construction progress. And secondly, the center point of the rail bearing table is arranged on the center line of the rail line, so that precise positioning of the prefabricated unit plate is achieved.

Description

Technical Field

[0001] This application relates to the field of track engineering, and more specifically, to a prefabricated track structure with inter-slab limiting and a method for slab placement in curved sections thereof. Background Technology

[0002] Modular slab track structures are a common structural form in urban rail transit, characterized by modularity and prefabrication. This structure is not limited by tunnel cross-sectional dimensions and eliminates the need for on-site casting, significantly improving construction efficiency and precision. Furthermore, its standardized manufacturing and assembly methods help ensure project quality, adapt to complex underground space conditions, and can be widely used in urban rail transit systems such as subways.

[0003] Currently, the limiting of unit plates between unit slab track structures is usually achieved through under-slab base groove limiting or grouting hole limiting. The base groove limiting measure is concealed under the slab, which can lead to unreliable and irreparable limiting when the track becomes detached. The grouting hole limiting measure is placed on the self-compacting filling layer, and the convex limiting structure is relatively weak, posing a safety risk. Secondly, for the construction of curved sections, the unit slab track structure requires the foundation to be constructed first, and then the precast track slabs are positioned using a fine-tuning device. After the closed formwork is erected, the under-slab filling layer is poured. The accuracy of positioning determines the laying accuracy of the precast track slabs. At present, the positioning of prefabricated track structures adopts the rail erection method, which makes it difficult to guarantee the positioning accuracy.

[0004] Therefore, how to improve the limiting stability between prefabricated unit plates and how to accurately position the curved segments have become technical problems that need to be solved in this field. Summary of the Invention

[0005] In view of this, this application proposes a prefabricated track structure with inter-plate limiting and a method for plate placement in curved sections.

[0006] According to the first aspect of this application, a precast track structure with inter-slab limiting is proposed. The track structure includes, from top to bottom, precast unit slabs, a filling adjustment layer, an isolation layer, and a concrete base. The precast unit slabs are precast structures, and a convex limiting structure is provided between adjacent precast unit slabs. The convex limiting structure is cast in place. The center point of the precast unit slab support platform is located on the center line of the track.

[0007] Preferably, the prefabricated unit plate has groove structures at both ends of its axial direction that cooperate with the convex limiting structure, and the horizontal cross section of the convex limiting structure is rectangular.

[0008] Preferably, the groove structure is inclined downward from the top surface of the prefabricated unit plate to the bottom surface of the prefabricated unit plate, and the inclination angle is 1.718° to 2.862°.

[0009] Preferably, the convex limiting structure is inclined from bottom to top so that the convex limiting structure cooperates with the groove structure.

[0010] Preferably, a buffer layer is provided between the groove structure and the convex limiting structure.

[0011] Preferably, the buffer layer is made of elastic inlaid wire foamed rubber sheet or polyurethane foam sheet.

[0012] Preferably, the precast unit plate is provided with grouting holes that run vertically through it. After the precast unit plate is hoisted above the isolation layer, a filling and adjustment layer is formed by grouting with self-leveling high-strength concrete. The isolation layer is geotextile.

[0013] Preferably, the precast unit plate is further provided with lifting holes and portal reinforcement bars. The lifting holes are provided at the four ends of the precast unit plate. One end of the portal reinforcement bar is embedded in the lower surface of the precast unit plate, and the other end is provided in the filling adjustment layer.

[0014] Preferably, the track structure further includes: a steel rail installed above the precast unit slab; a fastening system installed below the steel rail for installing the steel rail; a water-blocking platform disposed on both sides of the track structure, the height of the water-blocking platform being higher than the filling adjustment layer; and a drainage ditch disposed outside the water-blocking platform.

[0015] According to a second aspect of this application, a method for arranging slabs on curved sections of a track structure is proposed. This method involves using an iterative search algorithm to set the center point of the prefabricated unit slab support platform in the track structure on the center line of the track line. The track structure is the aforementioned prefabricated track structure with inter-slab limiting; wherein the prefabricated unit slab is a prefabricated structure, and a convex limiting structure is provided between adjacent prefabricated unit slabs, and the convex limiting structure is cast in place.

[0016] According to the precast track structure with inter-panel limiting in this application, a convex limiting structure is set between adjacent precast unit panels, and the convex limiting structure is cast on site. This can ensure the installation accuracy of the precast unit panels, ensure the tight fit between the convex limiting structure and the precast unit panels, ensure the lateral and longitudinal stability of the precast unit panels during operation, and ensure the safety of train operation. Secondly, setting the center point of the precast unit panel rail support platform on the center line of the track can achieve precise positioning of the precast unit panels.

[0017] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application, and the illustrative embodiments and descriptions thereof are used to explain this application. In the drawings:

[0019] Figure 1 This is a plan view of the track structure according to a preferred embodiment of this application.

[0020] Figure 2 This is a cross-sectional schematic diagram of the track structure according to a preferred embodiment of this application.

[0021] Figure 3 This is a plan view of a prefabricated unit plate according to a preferred embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the construction of a curved segment according to a preferred embodiment of this application. Detailed Implementation

[0023] The technical solution of this application will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] In rail transit, the precise positioning and limiting of prefabricated unit slabs are crucial for ensuring the long-term reliability of the track structure and the safe operation of trains, especially in curved track sections. In urban rail transit, the radius of curves is typically small, and the angle between adjacent prefabricated unit slabs is usually large, placing higher demands on the limiting and precise positioning of prefabricated unit slabs in curved sections.

[0025] Therefore, as Figure 1 and Figure 4 As shown, according to the first aspect of this application, a precast track structure with inter-slab limiting is proposed. The track structure includes, from top to bottom, a precast unit plate 1, a filling adjustment layer 2, an isolation layer 3, and a concrete base 4. The precast unit plate 1 is a precast structure, and a convex limiting structure 5 is provided between adjacent precast unit plates 1. The convex limiting structure 5 is cast in place. The center point 16 of the rail support platform of the precast unit plate 1 is located on the center line of the track.

[0026] The aforementioned filling adjustment layer 2, isolation layer 3, and concrete base 4 were all constructed on-site.

[0027] According to a second aspect of this application, a method for arranging slabs on curved sections of a track structure is proposed. This method involves using an iterative search algorithm to set the center point 16 of the prefabricated unit slab 1 rail support platform in the track structure on the center line of the track line. The track structure is the aforementioned prefabricated track structure with inter-slab limiting, wherein the prefabricated unit slab 1 is a prefabricated structure, and a convex limiting structure 5 is provided between adjacent prefabricated unit slabs 1. The convex limiting structure 5 is cast in place.

[0028] The precast unit slab curve layout utilizes a "straight line to approximate curve" method to ensure that the coordinates of the "center points of the first pair of rail supports" and the "center points of the last pair of rail supports" of precast unit slab 1 are located on the centerline of the track line, achieving precise positioning of precast unit slab 1 on the curve segment. When applying the iterative search algorithm, it is first assumed that the "center points of the first pair of rail supports" of the track slab coincide with the curve's straight-out and transition points. The position of the "center points of the last pair of rail supports" is then searched on the curve. The convergence criterion of the iterative search algorithm is to ensure that the absolute value of the difference between the straight-line distance between the two coordinate points and the slab length is less than or equal to 10. -6 After each slab completes the search and iterative calculation, the coordinates and rotation information of the center point 16 of the rail support platform of precast unit slab 1 are stored. The iterative search and calculation for the next precast unit slab 1 is then performed. During the calculation, the position information of the precast unit slab 1 needs to be determined, and the coordinate values ​​of the precast unit slab 1 are used to determine whether the slab is on a transition curve or a circular curve. After the iterative calculation is completed, the coordinates of the four corner points 15 of the precast unit slab 1 are derived from the coordinates of the center point 16 of the rail support platform, and finally, the precast unit slab 1 is accurately located.

[0029] According to the track structure applied to urban rail transit in this application, a convex limiting structure 5 is set between adjacent precast unit panels, and the convex limiting structure 5 is cast on site, providing adjustable margin for the precast unit panels, which can ensure the installation accuracy of the precast unit panels and ensure that the convex limiting structure 5 and the precast unit panels are tightly fitted, which can ensure the lateral and longitudinal stability of the precast unit panels during operation and ensure the safety of train operation; secondly, the basic method of the curved section plate layout method is to set the center point of the track slab precast unit panel support platform on the track line, which can achieve precise positioning of the track slab precast unit panels.

[0030] According to a preferred embodiment of this application, in order to limit the prefabricated unit plate 1 in the transverse and longitudinal directions and ensure the precise positioning of the prefabricated unit plate 1, groove structures that cooperate with the convex limiting structure 5 can be respectively provided at both ends of the prefabricated unit plate 1 in the axial direction. The horizontal cross-section of the convex limiting structure 5 is rectangular. The convex limiting structure 5 can be of an appropriate shape, such as a circle. In this application, it is preferably rectangular. The rectangular convex limiting structure 5 has clearer boundary restrictions in the transverse and longitudinal directions, a larger contact surface, and can prevent the prefabricated unit plate 1 from slipping or rotating under train load. The positioning accuracy of the rectangular convex limiting structure 5 is relatively higher; the force-bearing area is larger, and the structure is more stable.

[0031] The vertical cross-sections of the aforementioned groove structure 6 and convex limiting mechanism 5 can be rectangular, but in this application, trapezoidal is preferred. The groove structure 6 is inclined downwards from the top surface to the bottom surface of the prefabricated unit plate 1, with an inclination angle of 1.718° to 2.862°. In this application, an inclination angle of 1.718° is used as an example. The convex limiting structure 5 is inclined upwards to cooperate with the groove structure 6. In the horizontal direction, the rectangular convex limiting structure 5 can ensure the accurate positioning of the prefabricated unit plate 1. In the vertical direction, the convex limiting structure 5 can press down on the prefabricated unit plate 1 to a certain extent, preventing the prefabricated unit plate 1 from moving up and down during train operation, enhancing the fixing stability of the prefabricated unit plate 1, and preventing the prefabricated unit plate 1 from falling off the convex limiting structure 5, thereby improving the limiting effect of the convex limiting structure 5.

[0032] According to a preferred embodiment of this application, to avoid stress concentration caused by direct contact between rigid structures, a buffer layer 7 can be provided between the groove structure 6 and the convex limiting structure 5. The buffer layer 7 can absorb the impact and vibration generated by train operation, preventing stress concentration and structural damage caused by rigid contact, thereby effectively improving the stability of the track structure during operation. The buffer layer 7 can be made of a suitable material; for example, it can be made of elastic inlaid foam rubber sheet or polyurethane board; preferably, it is an elastic inlaid foam rubber sheet, which is placed directly inside the groove structure 6 during installation.

[0033] To ensure the flatness of the precast unit panels 1, such as Figure 3As shown, preferably, the precast unit slab 1 is provided with vertically penetrating grouting holes 8. After the precast unit slab 1 is hoisted above the isolation layer 3, concrete grouting is used to form a filling and adjustment layer 2. The filling and adjustment layer 2 is made of early-strength self-leveling concrete. The number of grouting holes 8 can be appropriate, for example, three, distributed along the axial direction of the precast unit slab 1. During construction, grout is injected into the grouting holes 8 located at both ends of the axial direction of the precast unit slab 1. The middle grouting hole 8 serves as a vent and observation hole. The grout is evenly filled at the bottom of the precast unit slab 1 without voids, and air is released through the vent to prevent air resistance and improve the fullness and quality of grouting. The middle vent can also serve as a marker for the completion of grouting. Symmetrical grouting on both sides helps to maintain the stability of the precast unit slab 1, ensuring construction accuracy and structural safety. By first placing the precast unit slab 1 and then grouting to form the filling adjustment layer 2, the height and flatness of the precast unit slab 1 can be precisely adjusted, and the fit between the precast unit slab 1 and the filling adjustment layer 2 and the overall bearing capacity can be improved. The aforementioned isolation layer 3 is geotextile. The geotextile is placed between the concrete base 4 and the precast unit slab 1 to isolate the upper precast unit slab 1 from the lower concrete base 4. When grouting the filling adjustment layer 2 below the precast unit slab 1, it prevents the grout from entering other areas, thereby improving grouting efficiency and grouting quality.

[0034] For ease of placement and further positioning of prefabricated unit panel 1, such as Figure 2 and Figure 3 As shown, preferably, the precast unit slab 1 may also be provided with lifting holes 9 and portal reinforcement 10. The lifting holes 9 are provided at the four ends of the precast unit slab 1. One end of the portal reinforcement 10 is embedded in the lower surface of the precast unit slab 1, and the other end of the portal reinforcement 10 is provided in the filling and adjustment layer 2. The two legs of the portal reinforcement 10 are set vertically upward. During the precasting of the precast unit slab 1, it is embedded in the precast unit slab 1. The horizontal connecting section of the portal reinforcement 10 is embedded in the filling and adjustment layer 2 during the construction of the filling and adjustment layer 2. This can enhance the integrity and long-term stability of the precast unit slab 1 and the track structure, and improve the overall strength of the structure.

[0035] Preferably, the track structure further includes: a rail 11 installed above the prefabricated unit plate 1; a fastening system 12 installed below the rail 11 for mounting the rail 11; a water-blocking platform 13 disposed on both sides of the track structure, the height of the water-blocking platform 13 being higher than the filling adjustment layer 2; and a drainage ditch 14 disposed outside the water-blocking platform 13. The water-blocking platform 13 and the drainage ditch 14 are arranged along the axial direction of the track structure. The rail 11 and the fastening system 12 are existing rails and fastening systems. The fastening system 12 is a commonly used fastener in rail transit, including gauge blocks, elastic clips, insulating blocks, bolts, spring washers, and rail pads.

[0036] The construction method for the track structure in this application is as follows:

[0037] (1) The “forward track laying method” was adopted. The concrete base 4 was constructed. The elevation of the top surface of the concrete base 4 was calculated by using the positioning corner point 15 of the precast unit plate 1. The position of the concrete base 4 was marked on the side formwork of the concrete base 4 as the control line for concrete pouring. The elevation of the base and the flatness of the surface were strictly controlled during construction. The concrete side formwork was made of shaped steel formwork with a thin rubber plate in the middle to prevent grout leakage. The bottom of the longitudinal formwork was fixed with anchor steel bars, and the top of the formwork was fixed with transverse tie rods.

[0038] (2) After the concrete base 4 is constructed, geotextile is laid, extending 160mm beyond the edges of the precast unit slab 1. The geotextile is spread out along the track line, and square holes are cut at the positions of the convex limiting structure 5. After laying the geotextile, protective pads should be immediately placed on top to prevent slippage, and personnel are prohibited from stepping on it. Before the formwork of the filling and adjustment layer 2 is installed and fixed, the geotextile is stretched flat.

[0039] (3) The precast unit slab 1 is laid in reverse order. At the track laying base, the precast unit slab 1, rails 11, fastener system 12, reinforcing bars, formwork and other construction materials are hoisted onto the track flatcar by the base gantry crane and transported to the laying work surface, where they are hoisted and laid using the track laying gantry crane. Using a total station, the midpoint of the end of the precast unit slab 1 is laid out with the track foundation control network as the reference, which serves as the initial positioning of the precast unit slab 1, the foundation for the installation of the convex limiting structure 5 and the reinforcing mesh in the filling adjustment layer 2.

[0040] (4) Applying the curved section layout scheme, firstly, the coordinate parameters of the four corner points 15 of the precast unit slab 1 are imported into the total station. The corresponding prisms at the four corners of the precast unit slab 1 are measured, and the measurement results are transmitted to the display next to the adjuster via a data transmission radio. After the precast unit slab 1 is initially laid, the three-way adjusters at the four corners of the precast unit slab 1 are installed for fine adjustment. After the precast unit slab 1 is laid and finely adjusted, the side templates and anti-floating devices are installed, and then the filling and adjustment layer 2 is poured.

[0041] (5) After the filling adjustment layer 2 between the precast unit plate 1 and the concrete base 4 is poured, the embedded wire foamed rubber sheet is placed in the groove structure 6, and the end groove structure 6 of the precast unit plate 1 is used as the boundary for the convex limiting structure 5 between the precast unit plates 1. Water-retaining platforms 13 are poured on both sides of the precast unit plate 1 and drainage ditches 14 are formed on the outside. The water-retaining platforms 13 are connected to the concrete base 4 and are higher than the precast unit plate 1 to prevent water from entering the track structure.

[0042] The preferred embodiments of this application have been described in detail above. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0043] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0044] Furthermore, various different embodiments of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content disclosed by this invention.

Claims

1. A precast track structure with inter-plate limiting, the track structure comprising, from top to bottom, precast unit plates (1), filling adjustment layer (2), isolation layer (3) and concrete base (4); in, The precast unit plate (1) is a precast structure, and a convex limiting structure (5) is provided between adjacent precast unit plates (1). The convex limiting structure (5) is cast on site. The center point (16) of the rail support platform of the precast unit plate (1) is located on the center line of the track.

2. The prefabricated track structure with inter-plate limiting as described in claim 1, characterized in that, The prefabricated unit plate (1) has groove structures (6) at both ends of its axial direction that cooperate with the convex limiting structure (5), and the horizontal cross section of the convex limiting structure (5) is rectangular.

3. The prefabricated track structure with inter-plate limiting as described in claim 2, characterized in that, The groove structure (6) is inclined downward from the top surface of the prefabricated unit plate (1) to the bottom surface of the prefabricated unit plate (1), and the inclination angle is 1.718° to 2.862°.

4. The prefabricated track structure with inter-plate limiting as described in claim 3, characterized in that, The convex limiting structure (5) is inclined from bottom to top so that the convex limiting structure (5) cooperates with the groove structure (6).

5. The prefabricated track structure with inter-plate limiting according to claim 2, 3, or 4, characterized in that, A buffer layer (7) is provided between the groove structure (6) and the convex limiting structure (5).

6. The prefabricated track structure with inter-plate limiting according to claim 5, characterized in that, The vibration damping buffer layer (7) is made of elastic embedded wire foamed rubber board or polyurethane foam board.

7. The prefabricated track structure with inter-plate limiting according to claim 2, characterized in that, The precast unit plate (1) is provided with grouting holes (8) that run vertically. After the precast unit plate (1) is hoisted above the isolation layer (3), self-leveling high-strength concrete is poured through the grouting holes (8) to form a filling adjustment layer (2). The isolation layer (3) is geotextile.

8. The prefabricated track structure with inter-plate limiting according to claim 7, characterized in that, The prefabricated unit plate (1) is also provided with lifting holes (9) and portal reinforcement (10). The lifting holes (9) are provided at the four ends of the prefabricated unit plate (1). One end of the portal reinforcement (10) is embedded in the lower surface of the prefabricated unit plate (1), and the other end is provided in the filling adjustment layer (2).

9. The prefabricated track structure with inter-plate limiting according to claim 1, characterized in that, The track structure also includes a rail (11) which is installed above the prefabricated unit plate (1); Fastening system (12), which is installed below the rail (11) for mounting the rail (11); A water-blocking platform (13) is provided on both sides of the track structure, and the height of the water-blocking platform (13) is higher than the filling adjustment layer (2); A drainage ditch (14) is provided on the outside of the water-blocking platform (13).

10. A method for arranging plates on curved sections of a track structure, characterized in that, The curve layout method uses an iterative search algorithm to set the center point (16) of the prefabricated unit plate (1) in the track structure on the center line of the track line. The track structure is a prefabricated track structure with inter-plate limiting as described in any one of claims 1-9. The prefabricated unit plate (1) is a prefabricated structure, and a convex limiting structure (5) is provided between adjacent prefabricated unit plates (1). The convex limiting structure (5) is cast on site.

Images