CN112848978A - Stray current drainage network system - Google Patents
Stray current drainage network system Download PDFInfo
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- CN112848978A CN112848978A CN202110234752.4A CN202110234752A CN112848978A CN 112848978 A CN112848978 A CN 112848978A CN 202110234752 A CN202110234752 A CN 202110234752A CN 112848978 A CN112848978 A CN 112848978A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M5/00—Arrangements along running rails or at joints thereof for current conduction or insulation, e.g. safety devices for reducing earth currents
- B60M5/02—Means for reducing potential difference between rail and adjacent ground
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M5/00—Arrangements along running rails or at joints thereof for current conduction or insulation, e.g. safety devices for reducing earth currents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M7/00—Power lines or rails specially adapted for electrically-propelled vehicles of special types, e.g. suspension tramway, ropeway, underground railway
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
- E01B1/00—Ballastway; Other means for supporting the sleepers or the track; Drainage of the ballastway
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Train Traffic Observation, Control, And Security (AREA)
Abstract
The invention discloses a stray current drainage net system which comprises a steel bar drainage net and a red copper bar, wherein the steel bar drainage net and the red copper bar are arranged in a structural section, the steel bar drainage net is formed by combining a plurality of longitudinal structural steel bars and transverse structural steel bars, and the red copper bar is longitudinally arranged and welded and fixed on any one longitudinal structural steel bar; the structure section is a ballast bed structure section or an overhead beam structure section; and connecting terminals are respectively arranged at two end parts of each structural section, the connecting terminals are fixedly connected with the reinforcing steel drainage net, and the adjacent structural sections are connected by arranging cables between the connecting terminals. The invention has the advantages that: the system is simple in structure, good conductivity can be guaranteed, once current leaks into a drainage network, the current can be collected and led back to a traction substation, a good drainage effect is achieved, and operation safety is improved; the drainage nets can be connected longitudinally along the line to form a complete collection net.
Description
Technical Field
The invention belongs to the technical field of rail transit, and particularly relates to a stray current drainage network system.
Background
The urban rail transit system generally adopts direct current as traction power and utilizes the backflow of running steel rails. Although the rails are installed in an insulating mode, due to the restriction of materials, technologies and other factors, the rails cannot be completely insulated from the ground. When the train operates, the traction reflux current can generate longitudinal voltage on the steel rail to form the ground potential of the steel rail. In the weak area of the rail insulation to the ground, part of the current leaks into the ground and cannot flow back to the traction substation according to the designed path, and the current is called stray current. When the metal reactivity of the surrounding medium conditions is different, the stray current will corrode the metal structure at the outflow position. In order to ensure the operation safety, the national relevant regulations have taken the stray current protection system as an important design content.
According to the specification of subway design GB50157-2013, article 15.7.3, a drainage reinforcing mesh is arranged in a ballastless track bed and is not electrically connected with other structural reinforcing steel bars, metal pipelines and grounding devices. The structural steel bars should not be used as drainage nets.
The regulations require that drainage reinforcing meshes be arranged in the ballast bed, but do not put specific practices on the drainage reinforcing meshes or the area requirements of the drainage mesh reinforcing bars into consideration. In addition, in the last sentence, the structural steel bars are definitely not used as drainage nets.
In the rail transit industry at present, the reinforcing steel bars in the ballast bed are adopted as drainage reinforcing steel bars in a general scheme, and the scheme is feasible, but has certain limitations.
Firstly, although not utilizing the structural reinforcement in the tunnel section of jurisdiction as the drainage net, reinforcing bar in the ballast bed is the reinforcing bar that sets up in order to guarantee that the ballast bed bears train weight, and relative ballast bed body, this reinforcing bar is ballast bed structural reinforcement promptly. There is some ambiguity with the last sentence of the standard clause.
Secondly, the track bed structure type, the track bed width and the structure depth are relatively fixed, the whole quantity of the track bed structure reinforcing steel bars and the sectional area of the reinforcing steel bars cannot be infinitely increased, so that the resistance value of the track bed structure reinforcing steel bars is limited, and the effect of the drainage net on collecting stray current is different due to the area of the reinforcing steel bar net, the communication effect and the equivalent resistance value.
Thirdly, the track traffic elevated section mostly adopts a track bed structure type of a supporting block and a rail bearing platform, and the total area of the reinforcing steel bars in the internal structure is difficult to meet the requirement of the area of the reinforcing steel bars of the drainage network.
In the current rail transit industry, the scheme of the elevated section is quite puzzled, and sometimes the design scheme has to utilize the surface layer structure steel bars of the elevated bridge to meet the area requirement in order to meet the area requirement of the drainage network. There is a certain gap from the last sentence of the standard clause.
In summary, it is necessary to optimize the current scheme, which can meet the specification requirements, and especially the last sentence of the sentence should not use the structural steel bars as drainage nets. And good drainage effect can be realized, and the method has important significance for improving the operation safety.
Disclosure of Invention
The invention aims to provide a stray current drainage net system according to the defects of the prior art, the drainage net system is characterized in that red copper bars are welded on longitudinal structural steel bars in a steel bar drainage net, and the resistance of the red copper bars is far smaller than that of the steel bars, so that most of current flows along a red copper bar loop when the current leaks into a ballast bed structure section or an overhead beam structure section according to the ohm law.
The purpose of the invention is realized by the following technical scheme:
a stray current drainage grid system is characterized by comprising a steel bar drainage grid and a copper bar, wherein the steel bar drainage grid is arranged in a structural section and is formed by combining a plurality of longitudinal structural steel bars and transverse structural steel bars, and the copper bar is longitudinally arranged and welded and fixed on any one of the longitudinal structural steel bars; the structure section is a ballast bed structure section or an overhead beam structure section; and connecting terminals are respectively arranged at two end parts of each structural section, the connecting terminals are fixedly connected with the reinforcing steel drainage net, and the adjacent structural sections are connected by arranging cables between the connecting terminals.
The red copper bar is rectangular, and the size is 30mm 4 mm.
The copper content in the red copper row is not less than 99.7%.
The structure section is a ballast bed structure section, the connecting terminals are respectively arranged on two sides of the end part of the ballast bed structure section, the lower parts of the connecting terminals are welded and fixed on the reinforcing steel drainage net, and the upper parts of the connecting terminals are 3-5mm higher than the upper surface of the ballast bed structure section.
The red copper bar is arranged along the length of the longitudinal structural steel bars in the ballast bed structure section, and welding points between the red copper bar and the longitudinal structural steel bars are smaller than 4.
The structure section is an elevated beam structure section, two rows of track rail bearing platforms extending longitudinally are arranged on the elevated beam structure section, and the red copper bars are respectively arranged on the longitudinal structural steel bars in each row of the track rail bearing platforms.
The lengths of the copper busbar and the elevated beam structure sections are the same, each row of track rail bearing platforms on each elevated beam structure section are formed by longitudinally splicing a plurality of track rail bearing platform sections, and the copper busbar and the longitudinal structural steel bars in each track rail bearing platform section are provided with at least one welding point.
The connecting terminals are respectively arranged on the outer side of the end part of the rail bearing platform, a circle of galvanized flat steel is arranged on the end part of the rail bearing platform, the galvanized flat steel comprises a horizontal flat steel which is transversely arranged and vertical flat steel which extends upwards from two end parts of the horizontal flat steel, the horizontal flat steel is welded with the longitudinal structural steel bars, and the vertical flat steel extends upwards and is connected with the connecting terminals.
The invention has the advantages that: the system is simple in structure, good conductivity can be guaranteed, once current leaks into a drainage network, the current can be collected and led back to a traction substation, a good drainage effect is achieved, and operation safety is improved; the drainage nets can be connected longitudinally along the line to form a complete collection net.
Drawings
FIG. 1 is a schematic plan view of a stray current drainage grid system in a structural section of a ballast bed according to the present invention;
FIG. 2 is a schematic view A-A of FIG. 1 according to the present invention;
FIG. 3 is an enlarged view of a portion of FIG. 2 in accordance with the present invention;
FIG. 4 is a cross-sectional view of a stray current drainage grid system in an elevated beam structure section of the present invention;
FIG. 5 is a plan view of a stray current drainage grid system in an elevated beam structure section of the present invention;
FIG. 6 is a schematic view of a connection terminal between sections of an elevated beam structure according to the present invention;
fig. 7 is a schematic structural view of a steel bar drainage net in the rail bearing platform of the invention.
Detailed Description
The features of the present invention and other related features are described in further detail below by way of example in conjunction with the following drawings to facilitate understanding by those skilled in the art:
referring to fig. 1-7, the symbols in the drawings are: reinforcing bar drainage net 1, vertical structure reinforcing bar 1a, horizontal structure reinforcing bar 1b, red copper row 2, welding point 3, connecting terminal 4, cable 5, test terminal 6, railway roadbed structure section 7, structure seam 8, overhead beam structure section 9, track rail bearing platform 10, zinc-plated band steel 11, horizontal band steel 11a, vertical band steel 11b, connecting cable 12.
Example 1: as shown in fig. 1, 2, and 3, the embodiment specifically relates to a stray current drainage grid system, which is applied to a ballast bed structure section 7, wherein copper bars 2 are arranged in reinforcing steel bar drainage grids 1 in the ballast bed structure section 7, and adjacent ballast bed structure sections 7 are communicated with each other through connecting terminals 4 and cables 5 to form the stray current drainage grid system in a longitudinally-through manner.
As shown in fig. 1, 2 and 3, the length of the monolithic track bed structure section 7 is generally 12.5m, and in a specific underground section scheme, a line is formed by longitudinally assembling a plurality of track bed structure sections 7, and a structure seam 8 is arranged between the adjacent track bed structure sections 7. Be provided with reinforcing bar drainage net 1 in each ballast bed structure section 7 respectively, reinforcing bar drainage net 1 specifically is formed by longitudinal structure reinforcing bar 1a and horizontal structural bar 1b welding or ligature combination, on this basis, welded fastening red copper bar 2 on arbitrary longitudinal structure reinforcing bar 1a wherein, red copper bar 2 sets up and keeps unanimous with ballast bed structure section 7's length along vertical logical length, ballast bed structure section 7 is according to 12.5m length, then red copper bar 2 should not be less than 4 with the welding point 3 of reinforcing bar, the welding point distributes evenly, in order to guarantee the reliability. The red copper bar 2 used in the embodiment is rectangular, the specification size is 30mm x 4mm, and in addition, the copper content in the red copper bar 2 is not less than 99.7%.
As shown in fig. 1, 2 and 3, two sides of the end of the ballast bed structure section 7 are respectively provided with 4 connecting terminals 4, specifically, the connecting terminals 4 are welded and fixed on the reinforcing steel bar drainage net 1 in the ballast bed structure section 7; the connecting terminals 4 are of an integrated structure, the upper portions of the terminals are made of copper materials, the purpose is to reliably connect with the cables 5 and effectively reduce the connection resistance, the lower portions of the terminals are made of steel bars, the purpose is to reliably weld with the drainage reinforcing mesh 1 in the ballast bed structure sections 7, and the cables 5 are arranged between the adjacent ballast bed structure sections 7 to longitudinally penetrate through the reinforcing mesh 1 and form a longitudinal penetrating drainage mesh along the line direction. It should be noted that the top of the connecting terminal 4 is 3-5mm higher than the upper surface of the ballast bed structure section 7 when the connecting terminal is arranged.
As shown in fig. 1, 2 and 3, during construction, the red copper bar 2 and the steel bar drainage net 1 should adopt a heat-release welding mode, and the welding with the longitudinal structural steel bar 1a can be completed in a workshop in advance, and then the welding with the transverse structural steel bar 1b can be carried out on a construction site.
In this embodiment, still be provided with test terminal 6 on reinforcing bar drainage network 1, set up test terminal 6 and mainly be in order to monitor reinforcing bar drainage network 1's polarization potential, still have one set of monitoring system among the actual engineering design, carry out real-time supervision to reinforcing bar polarization potential, the standard requirement is not higher than 0.1V.
After the field installation is completed, field detection can be performed, and the specific method comprises the following steps:
(1) after the welding of the steel bars is finished, the longitudinal structural steel bars 1a between the connecting terminals 4 of each ballast bed structure section 7 are tested by an electric bridge method, and the longitudinal structural steel bars 1a are tested for 4 times each time in a cross test mode. After the construction is finished, the construction is retested, the measurement is carried out for 4 times each time, the cross measurement is carried out, the average value is taken, the measurement result is recorded and the identification is found by the supervision field.
(2) A loop resistance tester (microohm meter) or a direct current resistance meter using a bridge method or a voltammetry method. The minimum value of the measuring range of the meter is not more than 1m omega, and the resolution is 1u omega. The voltammetry meter comprises a SB2230 digital resistance measuring instrument, a YZZ-10 direct current resistance measuring instrument and the like.
(3) The longitudinal resistance value of the connecting terminals 4 at two ends of the roadbed structure section 7 of each test unit (the underground section is 50 meters, and the elevated section is 30 meters) is not more than 6m omega before concrete pouring, and if the measurement result does not meet the requirement, the resistance can be reduced by increasing welding points of reinforcing steel bars. After pouring, the longitudinal resistance of each test unit of the concrete connecting terminal 4 is not more than 8m omega, and the longitudinal resistance of a special section is not more than 10m omega.
The working method of the stray current drainage grid system in the embodiment is as follows: the urban rail transit system adopts direct current as traction power and utilizes traveling steel rail backflow. Although the rails are installed in an insulating mode, due to the restriction of materials, technologies and other factors, the rails cannot be completely insulated from the ground. When the train operates, the traction reflux current can generate longitudinal voltage on the steel rail to form the ground potential of the steel rail. In the weak area of the rail insulation to the ground, part of the current leaks into the ground and cannot flow back to the traction substation according to the designed path, and the current is called stray current. Stray current flows through the reinforcing steel bar drainage net 1 and flows back to the negative electrode of the traction substation, wherein the resistance of the red copper bar 2 is far smaller than that of the reinforcing steel bar, so that after current leaks into the reinforcing steel bar drainage net 1 in the ballast bed structure section 7, most of current flows along the red copper bar 2 loop.
Example 2: as shown in fig. 4 to 7, the embodiment specifically relates to a stray current drainage grid system, which is applied to an elevated beam structure section 9, wherein copper bars 2 are arranged in reinforcing steel bar drainage grids 1 in a track support platform 10 on the elevated beam structure section 9, and adjacent elevated beam structure sections 9 are communicated with each other through connecting terminals 4 and cables 5 to form a longitudinally-through stray current drainage grid system.
As shown in fig. 4-7, in this embodiment, the elevated beam structure section 9 is a relatively independent box beam structure with a length of 30 meters, and the elevated beam structure sections 9 are arranged along the line direction in a splicing manner, so that there is a boundary on the whole elevated line every 30 meters. Arranged track rail bearing platform 10 on overhead beam structure section 9, track rail bearing platform 10 comprises a plurality of rail bearing platform segments along the line direction concatenation, arranged reinforcing bar drainage net 1 in the track rail bearing platform 10, reinforcing bar drainage net 1 specifically is formed by longitudinal structure reinforcing bar 1a and transverse structure reinforcing bar 1b welding combination, on this basis, welded fastening red copper bar 2 on arbitrary longitudinal structure reinforcing bar 1a wherein, red copper bar 2 sets up and keeps unanimous along vertical through length and with the length of overhead beam structure section 9. The red copper bar 2 is welded with the corresponding longitudinal structural steel bars 1a in the workshop in advance through exothermic welding (not less than 10 welding points, and welding points are guaranteed to be arranged in each track bearing table segment), and then the longitudinal structural steel bars 1a on the red copper bar 2 and all the transverse structural steel bars 1b crossed in the track bearing table 10 are reliably welded. In this embodiment, the red copper bar 2 is mostly arranged in the lower layer steel bar of the rail bearing platform 10, and is suitable for being leveled with the height of the bridge surface layer, so as to ensure the beauty. The red copper bar 2 used in the embodiment is rectangular, the specification size is 30mm x 4mm, and in addition, the copper content in the red copper bar 2 is not less than 99.7%.
As shown in fig. 4-7, two sides of the rail bearing platform 10 at the end of the elevated beam structure section 9 are respectively provided with 4 connecting terminals 4, specifically, the connecting terminals 4 are welded and fixed on the steel bar drainage net 1 in the rail bearing platform 10; the cables 5 are arranged between the connecting terminals 4 between the adjacent elevated beam structure sections 9, so that the longitudinal through of the reinforcing steel bar drainage net 1 is realized, and the longitudinal through drainage net along the line direction is formed. It should be noted that the top of the connection terminal 4 is 3-5mm higher than the upper surface of the rail support platform 10 when being installed. In addition, a connecting cable 12 for connection can be arranged between the connecting terminals 4 between the two parallel rows of track bearing platforms 10, so that the longitudinal communication effect of the drainage network is improved.
As shown in fig. 5 and 7, a circle of galvanized flat steel 11 is arranged at the end of the rail bearing platform 10, the galvanized flat steel 11 comprises a horizontal flat steel 11a which is transversely arranged and vertical flat steel 11b which extends upwards from two ends of the horizontal flat steel 11a, the horizontal flat steel 11a is welded with each longitudinal structural steel bar 1a which is positioned at the bottom, the vertical flat steel 11b extends upwards and is connected with the connecting terminal 4, the contact area of key parts can be increased, and the longitudinal communication effect of the drainage net can be improved. Wherein, the material of the galvanized flat steel 11 is hot-dip galvanized flat steel with the specification of 40mm 4 mm.
Claims (8)
1. A stray current drainage grid system is characterized by comprising a steel bar drainage grid and a copper bar, wherein the steel bar drainage grid is arranged in a structural section and is formed by combining a plurality of longitudinal structural steel bars and transverse structural steel bars, and the copper bar is longitudinally arranged and welded and fixed on any one of the longitudinal structural steel bars; the structure section is a ballast bed structure section or an overhead beam structure section; and connecting terminals are respectively arranged at two end parts of each structural section, the connecting terminals are fixedly connected with the reinforcing steel drainage net, and the adjacent structural sections are connected by arranging cables between the connecting terminals.
2. The system for draining stray currents of claim 1, wherein said row of copper bars is rectangular and has dimensions of 30mm by 4 mm.
3. A stray current drainage grid system according to claim 1, wherein the copper content in said copper rows is not less than 99.7%.
4. The system for draining stray currents according to claim 1, wherein said structural section is a ballast bed structural section, said connecting terminals are respectively disposed at two sides of an end of said ballast bed structural section, a lower portion of said connecting terminal is welded to said reinforcing bar drainage net, and an upper portion of said connecting terminal is 3-5mm higher than an upper surface of said ballast bed structural section.
5. A stray current drainage grid system according to claim 4, wherein said copper bars are arranged along the length of said longitudinal structural steel bars in said ballast bed structure section, and the number of welds between said copper bars and said longitudinal structural steel bars is less than 4.
6. The system for draining stray currents of claim 1, wherein said structural sections are elevated beam structural sections having two rows of longitudinally extending rail support platforms disposed thereon, said copper busbar being disposed on said longitudinal structural steel reinforcement bars in each of said rows of rail support platforms, respectively.
7. The system for draining stray currents of claim 6, wherein said row of copper bars is of the same length as said elevated beam structure sections, each said row of said rail support platforms on each said elevated beam structure section being comprised of a plurality of rail support platform segments longitudinally spliced together, said row of copper bars having at least one weld with said longitudinal structural reinforcing bar within each said rail support platform segment.
8. A stray current drainage network system according to claim 6, wherein said connection terminals are respectively disposed outside of said rail support platform ends, said rail support platform ends being disposed with a ring of galvanized flat steel, said galvanized flat steel including a horizontally disposed horizontal flat steel welded to each of said longitudinal structural steel bars and vertical flat steel extending upwardly from both ends of said horizontal flat steel and connected to said connection terminals.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110234752.4A CN112848978A (en) | 2021-03-03 | 2021-03-03 | Stray current drainage network system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110234752.4A CN112848978A (en) | 2021-03-03 | 2021-03-03 | Stray current drainage network system |
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| CN112848978A true CN112848978A (en) | 2021-05-28 |
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| CN202110234752.4A Pending CN112848978A (en) | 2021-03-03 | 2021-03-03 | Stray current drainage network system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023177844A1 (en) * | 2022-03-18 | 2023-09-21 | Craig Alfred B | Stray current mitigation assemblies having a carbon conduction subassembly |
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2021
- 2021-03-03 CN CN202110234752.4A patent/CN112848978A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023177844A1 (en) * | 2022-03-18 | 2023-09-21 | Craig Alfred B | Stray current mitigation assemblies having a carbon conduction subassembly |
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