Construction Transition Method for Jacked Bridge Culverts in Turnout Areas

Abstract

This application relates to the technical field of bridge construction. Specifically, it relates to a construction transition method for jacking culverts in the turnout area. By obtaining the minimum influence length of the jacked culvert on the turnout area and the jacking speed of the jacked culvert, the shortest influence time of the jacked culvert on the turnout area is obtained. In this way, the influence time of the turnout area is determined, avoiding long-term random lateral locking, thereby facilitating the clarification of the conditions for lateral locking and unlocking of the turnout. Subsequently, it is convenient to achieve the transition of railway transportation in the turnout area when jacking culverts in the railway turnout area through overall allocation based on the calculation of the station traffic volume.

Description

Technical Field

[0001] This application relates to the technical field of bridge construction, and specifically, to a construction transition method for jacking bridge culverts in a turnout area. Background Art

[0002] The jacked railway bridge culvert is a technical solution for crossing under the railway without interrupting railway operations. At the same time, compared with the overpass railway bridge plan, it has advantages such as less land occupation, less demolition volume, less investment, and easy engineering, so it is widely used. The railway station area belongs to a densely populated, traffic-intensive, and building-intensive area. In municipal engineering, it is inevitable to use jacking bridge culverts to cross the turnout in the station yard or throat area.

[0003] When the bridge culvert is jacked under the existing railway using the jacking method, it is necessary to excavate the subgrade soil under the existing railway line to achieve the jacking of the bridge culvert. The excavation of the soil will inevitably affect the existing line. To ensure the safety of railway operations, it is necessary to pre-reinforce the railway line before the jacking construction of the bridge culvert. Since the pre-reinforcement method of the railway line cannot effectively guarantee the stability of the turnout area and the safety of train operation, in the crossing project of the railway turnout area, it is often required to laterally lock the turnout. However, the traffic density in the turnout area is often high, and long-term lateral locking will greatly affect the railway transportation organization. Summary of the Invention

[0004] An embodiment of this application provides a construction transition method for jacking bridge culverts in a turnout area to solve the problem that long-term lateral locking of the turnout will greatly affect the railway transportation organization.

[0005] To achieve the above object, this application provides the following technical solutions:

[0006] A construction transition method for jacking bridge culverts in a turnout area provided by an embodiment of this application includes:

[0007] Obtain the minimum influence length of the jacking bridge culvert on the turnout area;

[0008] Obtain the jacking speed of the jacking bridge culvert;

[0009] Obtain the shortest influence time of the jacking bridge culvert on the turnout area according to the minimum influence length and the jacking speed.

[0010] Further, the obtaining of the minimum influence length of the jacking bridge culvert on the turnout area includes:

[0011] Obtain the height of the jacking bridge culvert in the turnout area and the length of the reinforced concrete cutting edge angle of the jacking bridge culvert.

[0012] Further, the obtaining of the minimum influence length of the jacking bridge culvert on the turnout area further includes:

[0013] Perpendicular lines are respectively drawn from the turnout head and the turnout root of the turnout area to the jacking axis of the jacked culvert to obtain the length from the turnout head to the turnout root in the jacking direction of the jacked culvert, wherein the jacking axis is parallel to the jacking direction.

[0014] Further, obtaining the minimum influence length of the jacked culvert on the turnout area further includes:

[0015] According to the internal friction angle of the soil mass in the jacking area corresponding to the jacked culvert and according to the Mohr-Coulomb strength criterion, the soil mass rupture angle of the jacking area is obtained.

[0016] Further, obtaining the minimum influence length of the jacked culvert on the turnout area further includes:

[0017] Obtain the over-excavated length of the jacked culvert during the jacking process.

[0018] Further, the minimum influence length satisfies the following formula:

[0019] L = (H × tanα + L3) - L1 + L2 + C,

[0020] wherein, L represents the minimum influence length, H represents the height of the jacked culvert, α represents the soil mass rupture angle of the jacking area, L3 represents the over-excavated length, L1 represents the length of the reinforced concrete cutting edge angle, L2 represents the length from the turnout head to the turnout root in the jacking direction of the jacked culvert, and C represents the safety constant.

[0021] Further, the shortest influence time satisfies the following formula:

[0022]

[0023] wherein, L represents the minimum influence length, and v represents the jacking speed.

[0024] Further, the safety constant is 2.

[0025] Further, the soil mass rupture angle of the jacking area satisfies the following formula:

[0026]

[0027] wherein, α represents the soil mass rupture angle of the jacking area, represents the internal friction angle of the soil mass in the jacking area.

[0028] Further, drawing the perpendicular lines from the turnout head and the turnout root of the turnout area to the jacking axis of the jacked culvert respectively includes:

[0029] Determine the positions of the frog head and frog root of the turnout area within the influence range of the jacked bridge or culvert.

[0030] In the construction transition method for jacking a bridge or culvert in the turnout area provided in the embodiments of the present application, compared with the prior art, it has the following technical effects: By obtaining the minimum influence length of the jacked bridge or culvert on the turnout area and the jacking speed of the jacked bridge or culvert, the shortest influence time of the jacked bridge or culvert on the turnout area is obtained, thus determining the influence time of the turnout area, avoiding long-term random lateral locking, and facilitating the clarification of the conditions for lateral locking and unlocking of the turnout. Furthermore, it is convenient to achieve the transition of railway transportation in the turnout area when jacking a bridge or culvert in the railway turnout area through overall allocation based on the measurement of the station traffic volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0032] Figure 1 It is a schematic diagram of the relative position relationship between the jacked bridge or culvert and the railway turnout in one or more embodiments of the present application;

[0033] Figure 2 It is a simplified calculation diagram of the minimum influence length and the shortest influence time of jacking a bridge or culvert in the railway turnout area in one or more embodiments of the present application.

[0034] Figure 3 It is a schematic diagram of an alternative parallel route in one or more embodiments of the present application.

[0035] The reference signs in the drawings are as follows:

[0036] 11. Frog head 11; 12. Switch rail; 13. Frog root 13; 14. Starting position of the jacked bridge or culvert; 15. Position where the jacked bridge or culvert is in place; 16. Starting excavation pit; 17. Excavation stable surface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] In the embodiments of the present application, a construction transition method for jacking a bridge or culvert in the turnout area is provided to solve the problem that long-term lateral locking of the turnout will greatly affect the organization of railway transportation.

[0038] In order to make the technical solutions and advantages in the embodiments of the present application clearer and more understandable, the following further describes the exemplary embodiments of the present application in detail with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than an exhaustive list of all embodiments. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0039] In the project of jacking culverts under the station yard or the turnout throat area with limited construction conditions, this application combines the station yard transportation organization and the culvert jacking construction, and proposes a relatively reasonable transition method for the culvert jacking construction in the turnout area and the railway transportation, so as to meet the dual requirements of construction and transportation.

[0040] In one or more embodiments, the present disclosure provides a transition method for culvert jacking construction in the turnout area, which includes:

[0041] Obtain the minimum influence length of the jacking culvert on the turnout area;

[0042] Obtain the jacking speed of the jacking culvert;

[0043] Obtain the shortest influence time of the jacking culvert on the turnout area according to the minimum influence length and the jacking speed.

[0044] It should be noted that when determining the jacking speed, the jacking speed can be determined according to the engineering geology, the groundwater level, the scale of the culvert, and the jacking force per meter in length.

[0045] The transition method for culvert jacking construction in the turnout area provided by at least one embodiment obtains the minimum influence length of the jacking culvert on the turnout area and the jacking speed of the jacking culvert, so as to obtain the shortest influence time of the jacking culvert on the turnout area. In this way, the influence time of the turnout area is determined, and the long-term random lateral locking is avoided, so as to facilitate the clarification of the conditions for lateral locking and unlocking of the turnout. Furthermore, it is convenient to realize the transition of railway transportation in the turnout area when jacking culverts in the railway turnout area through the overall allocation of the measured traffic volume of the station.

[0046] In some embodiments, obtaining the minimum influence length of the jacking culvert on the turnout area includes:

[0047] Obtain the height of the jacking culvert in the turnout area and the length of the reinforced concrete cutting edge angle of the jacking culvert.

[0048] In some embodiments, obtaining the minimum influence length of the jacking culvert on the turnout area further includes:

[0049] Draw perpendicular lines from the switch point 11 and the switch root 13 of the turnout area to the jacking axis of the jacking culvert respectively, so as to obtain the length from the switch point 11 to the switch root 13 in the jacking direction of the jacking culvert, wherein the jacking axis is parallel to the jacking direction.

[0050] In some embodiments, obtaining the minimum influence length of the jacking culvert on the turnout area further includes:

[0051] According to the internal friction angle of the soil mass in the jacking area corresponding to the jacked bridge culvert and based on the Mohr-Coulomb strength criterion, the soil rupture angle of the jacking area is obtained. It should be noted that when determining the rupture angle, the rupture line can be used as the excavation stable surface 17 during the jacking process of the bridge culvert. When the turnout is entirely located on the subgrade behind the excavation stable surface 17 from the turnout nose 11 to the turnout heel 13 or entirely located on the top surface of the bridge culvert, the turnout is entirely located on the stable support point, and the stability can meet the specification requirements. For the construction transition method of the jacked bridge culvert in the turnout area, when jacking the jacked bridge culvert, it starts from the starting position 14 of the jacked bridge culvert and continues until the jacked bridge culvert is jacked to the in-place position 15 of the jacked bridge culvert; the starting position of the jacked bridge culvert is in the starting foundation pit 16.

[0052] In some embodiments, obtaining the minimum influence length of the jacked bridge culvert on the turnout area further includes:

[0053] Obtaining the over-excavation length of the jacked bridge culvert during the jacking process.

[0054] In some embodiments, the minimum influence length satisfies the following formula:

[0055] L = (H × tanα + L3) - L1 + L2 + C,

[0056] where L represents the minimum influence length, H represents the height of the jacked bridge culvert, α represents the soil rupture angle of the jacking area, L3 represents the over-excavation length, L1 represents the length of the reinforced concrete cutting edge angle, L2 represents the length from the turnout nose 11 to the turnout heel 13 in the jacking direction of the jacked bridge culvert, and C represents the safety constant.

[0057] In some embodiments, the shortest influence time satisfies the following formula:

[0058]

[0059] where L represents the minimum influence length and v represents the jacking speed.

[0060] It should be noted that during the jacking process of the bridge culvert, the over-excavation length and a safety distance of 1.0 m on each side of the stable support point. Starting from the position where the distance between the stable slope surface formed after excavation from the front end of the reinforced concrete cutting edge angle and the turnout nose 11 or turnout heel 13 is not greater than 1.0 m, until the turnout nose 11 and turnout heel 13 are all located not less than 1.0 m above the cutting edge angle of the frame bridge, the jacking stroke during this process is the minimum influence length of the turnout area, and the required jacking duration is the shortest influence time. Figure 1 The switch rail 12 of the turnout is also shown.

[0061] In some embodiments, the safety constant is 2, and the unit of the safety constant is meters, which is the sum of the safety distances on both sides of the stable support point, that is, 1.0 m + 1.0 m = 2 m.

[0062] In some embodiments, the soil rupture angle in the jacking area satisfies the following formula:

[0063]

[0064] where α represents the soil rupture angle in the jacking area, represents the internal friction angle of the soil in the jacking area.

[0065] In some embodiments, perpendicular lines are drawn from the switch nose 11 and the switch heel 13 of the turnout area to the jacking axis of the jacking bridge and culvert respectively, including:

[0066] Determine the positions of the switch nose 11 and the switch heel 13 of the turnout area within the influence range of the jacking bridge and culvert.

[0067] It should be noted that in some other embodiments, after obtaining the shortest influence time of the jacking bridge and culvert on the turnout area according to the minimum influence length and the jacking speed, the construction transition method for jacking a bridge and culvert in the turnout area provided by the present disclosure further includes: according to the shortest influence time and combined with the station yard transportation organization situation, formulating alternative parallel routes, and after overall calculation of the transportation capacity of the whole station, making overall allocation to minimize cross interference and ensure smooth and orderly station yard transportation organization. In addition, for the minimum influence length and the shortest influence time of the jacking bridge and culvert in the turnout area, it is only for one turnout in the turnout area, and the construction transition method for jacking a bridge and culvert in the turnout area can determine the minimum influence length and the shortest influence time for different turnouts.

[0068] A specific application example of the construction transition method for jacking a bridge and culvert in the turnout area of the present application is:

[0069] As Figure 1 shown, first, according to the positional relationship between the jacking bridge and culvert and the railway, analyze the geometric characteristics of the jacking bridge and culvert and the turnout area within the influence range, and determine the accurate positions of the switch nose 11 and the switch heel 13.

[0070] Secondly, according to Figure 2 the calculation sketch shown, and the construction organization design, determine the jacking direction and the jacking speed v of the frame bridge, and calculate the minimum influence length L and the shortest influence time T of the jacking bridge and culvert in the railway turnout area.

[0071] Finally, refer to Figure 3As shown in the figure, investigate the use function of the turnout in the jacking influence area and the station yard transportation organization situation. Take the No. 1 turnout as an example to find an alternative parallel route. Since the No. 1 turnout is a main line turnout and the transition plan is relatively complex, the transition plan is specified with the No. 1 turnout as an example: the No. 1 turnout is laterally locked, which only affects the arrival of passenger trains from the direction of C Station to Track 1. Currently, there are 14 pairs of passenger trains in the operation diagram, which need to be transferred to IV / V / 7 / 8 (double track), and handled at 4 passenger train arrival and departure tracks. After calculating the capacity of the whole station, about 49 pairs of passenger train arrivals and departures can be handled at these 4 passenger train arrival and departure tracks of IV / V / 7 / 8, and the capacity can meet the requirements. At this time, it should be noted that due to the real-time adjustment of passenger and freight traffic according to the actual train operation situation, the receiving and dispatching tracks are not fixed, and there may be multiple alternative parallel routes, which need to be determined after approval during the specific implementation process.

[0072] In summary, the construction transition method for jacking culverts in the turnout area provided by this application determines the minimum influence length and the shortest influence time in the turnout area by analyzing turnout characteristics, jacking culvert construction organization design, soil excavation and stability surface, etc., clarifies the timing of lateral locking and unlocking of the turnout, solves the problem of long-term lateral locking of the turnout during existing culvert jacking, proposes the idea of alternative parallel routes, and minimizes the impact on railway operation; on the premise of ensuring railway safety, it improves the operation efficiency, provides ideas and calculation methods for future similar projects, and has positive guiding significance.

[0073] Although the preferred embodiments of this application have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concepts. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of this application.

[0074] Obviously, those skilled in the art can make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application is also intended to include these modifications and variations.

Claims

1. A construction transition method for jacking bridges and culverts in the turnout area, characterized in that, Including: Obtaining the minimum influence length of the jacking culvert on the turnout area; Obtaining the jacking speed of the jacking culvert; Obtaining the shortest influence time of the jacking culvert on the turnout area according to the minimum influence length and the jacking speed; The obtaining of the minimum influence length of the jacking culvert on the turnout area includes: Obtaining the height of the jacking culvert in the turnout area and the length of the reinforced concrete cutting edge angle of the jacking culvert; The obtaining of the minimum influence length of the jacking culvert on the turnout area further includes: Respectively drawing perpendicular lines from the turnout nose and turnout heel of the turnout area to the jacking axis of the jacking culvert to obtain the length from the turnout nose to the turnout heel in the jacking direction of the jacking culvert, wherein the jacking axis is parallel to the jacking direction; The obtaining of the minimum influence length of the jacking culvert on the turnout area further includes: Obtaining the soil rupture angle of the jacking area according to the internal friction angle of the soil in the jacking area corresponding to the jacking culvert and according to the Mohr-Coulomb strength criterion; The obtaining of the minimum influence length of the jacking culvert on the turnout area further includes: Obtaining the over-excavation length of the jacking culvert during the jacking process; The minimum influence length satisfies the following formula: L = (H×tanα + L3) - L1 + L2 + C, wherein, L represents the minimum influence length, H represents the height of the jacking culvert, α represents the soil rupture angle of the jacking area, L3 represents the over-excavation length, L1 represents the length of the reinforced concrete cutting edge angle, L2 represents the length from the turnout nose to the turnout heel in the jacking direction of the jacking culvert, and C represents a safety constant.

2. The construction transition method of the jacked culvert in the turnout area according to claim 1, characterized in that, The shortest influence time satisfies the following formula: wherein, L represents the minimum influence length and v represents the jacking speed.

3. The construction transition method of the jacked bridge culvert in the turnout area according to claim 1 or 2, characterized in that, The safety constant is 2.

4. The construction transition method of the jacked bridge culvert in the turnout area according to claim 1 or 2, characterized in that, The soil rupture angle of the jacking area satisfies the following formula: Wherein, α represents the soil rupture angle of the jacking area, and represents the internal friction angle of the soil in the jacking area.

5. The construction transition method for the jacked culvert in the turnout area according to any one of claims 1-2, characterized in that, The respectively drawing of perpendicular lines from the turnout nose and turnout heel of the turnout area to the jacking axis of the jacking culvert includes: Determining the positions of the turnout nose and turnout heel of the turnout area within the influence range of the jacking culvert.

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