Introduction of Catenary Embedded Foundation and Parts
The catenary embedded foundation refers to embedded plates for both catenary mast and guy/stay wire, which consist of masts, embedded steel plates and high-strength anchor bolt. The function is bearing the entire load of the contact suspension, mast, and positioning devices, and fix the contact suspension at the specified position and height.
AGICO supplies embedded parts for various types of catenary masts, according to the functions in the catenaries, masts can be classified into the following types: Intermediate Masts, Anchor Masts, Transition Masts, Central Masts, Registration Masts, Flexible Cross-span Masts, Rigid Cross-span Masts, and Turnout Masts.
Both prestressed reinforced concrete masts and H-beam or steel box section column masts are widely used for catenary systems. The embedded plate foundation is composed of steel plate and anchors. Its structure bears the entire load transmitted from the catenary mast and ensures its’ stability. The prestressed reinforced concrete foundation is made as a single unit, with the lower end directly buried in the ground.
Why Use Embedded Parts for Catenary System?
- Catenary System for High-Speed Railway: China has the most advanced high-speed railway in the world. Construction standards of embedded parts of high-speed railway have been continuously upgraded, now the requirements for catenary system are more stringent, such as the verticality of embedded bolts, the relative spacing of the central axis, and the exposed length of bolts.
- Disadvantages of Embedded Bolt Fastening: The installation of embedded bolts for catenary systems mostly involves welding to the stirrups of the reinforcing cage, using a single-layer positioning device for control. However, this positioning control is only installed before pouring concrete, and it cannot control its accuracy after concrete pouring. During vibration, the central axis is easily displaced, resulting in non-vertical embedded bolts, affecting construction quality.
Catenary Embedded Parts Fabrication Service
AGICO supplies cutomized fabrication service of embedded plates and anchor bolts for catenary mast and guy wire anchors. Check the following specificaitons, if you are looking for catenary embedded parts manufacturer, contact us for a free quote now!
Mast Embedded Anchor Plate
- Material: Q355D (Embedded Steel Plate), Q355B (Anchor Bolts)
- Surface Treatment: Multi-alloy powder co-diffusion + passivation + sealing
- Application: The high-speed railway catenary mast embedded anchor plate is designed specifically for use in electrified railway systems. Compared with standard catenary masts, high-speed rail masts are taller and engineered to effectively reduce dynamic wind loads generated by high-speed trains.
- Standard: Q/CR 749.3-2020 Coating and Paint Protection for Railway Bridge Steel Structures and Components.
Dropper / Stay Wire Embedded Anchor Plate
- Material: Q355D (Embedded Steel Plate), Q355B (Anchor Bolts)
- Surface Treatment: Multi-alloy powder co-diffusion + passivation + sealing
- Application: The dropper/stay wire embedded anchor system consists of an embedded steel plate, bolts, nuts, and washers. These components are embedded in the bridge decks and subgrades of electrified railway systems — including both conventional and high-speed railways. During installation of the electrification masts, the base is connected to the threaded portion of the pre-embedded bolts (with the thread section aligned parallel to the bridge or ground surface).
- Standard: Q/CR 749.3-2020 Coating and Paint Protection for Railway Bridge Steel Structures and Components.
Mast Embedded Anchor Plate Installation:
- During prefabrication, embedded steel plate is welded to the anchor bolt head according to construction drawings, make sure the anchor bolt is perpendicular to the embedded plate.
- Apply grease to the exposed threaded section of the anchor bolt and secure it with protective wrapping to prevent thread damage.
- After position calibration, proceed with the rebar binding or welding process.
Stay Wire Embedded Anchor Plate Installation:
- Workers shall place the assembly jig horizontally on the work platform, ensuring both levelness and vertical alignment meet the construction tolerance requirements.
- Then position the embedded steel plate horizontally on the jig, aligning the bolt holes precisely with the jig openings, and insert the anchor bolts.
- After install is completed, check the embedded plate levelness and bolt verticality; once spacing accuracy is verified, proceed with welding operations.
Embedded Plate and Anchor Specifications
Embedded parts for catenary systems mainly include embedded steel plates, bolts, and reinforcing bars, and their specifications and requirements are as follows:
| Component | Specification / Requirement |
|---|---|
| Embedded Steel Plate | Thickness 10 mm; used in mast foundation and dropper/Guy-wire embedded foundation. |
| Embedded Anchor Bolts | M39 bolts for mast foundations; M24 bolts for dropper/Guy-wire embedded foundations; material Q345 (16Mn). |
| Tunnel Cantilever Mast | M20 chemical anchor bolts. |
| Return-Current Shoulder Frame | M12 chemical anchor bolts. |
| Return-Current Opposite Down Anchor | M16 chemical anchor bolts. |
| Bridge Pier (Beam or Column) | M30 chemical rebar anchors. |
| Continuous-Beam Reserved Pier | M30 chemical rebar anchors. |
| Mast Foundation (Alternative) | M42 foundation bolts. |
| Stay-Wire / Guy-Wire Foundation (Alternative) | M39 foundation bolts. |
Inspections of Cantenary Foundation Embedded Parts
The mast foundation and embedded parts are the core structure members in the catenary system, here are the basic inspections required during installation:
- Anchoring Force Inspection: Inspecting the anchoring force of embedded components to ensure they will not loosen or sink during long-term operation.
- Dimensional Accuracy: Using measuring instruments to check whether the dimensions of embedded and reserved components meet design requirements, avoiding impacts on subsequent installation due to dimensional discrepancies.
- Positional Deviation: Measuring the installation position of foundation embedded components using a laser meter or total station to ensure consistency with design drawings, avoiding interference with the positioning of the contact line equipment.
Installation of Embedded Parts for Catenary
The catenary embedded plate foundations are divided into 4 types: QJ-A1, QJ-A2, QJ-B, and QJ-C. The anchor wire foundation is of only type QJLX-1. All are located on the outer side of the route, with the foundation center 3.15m from the route (the foundation center is 5.65m from the bridge centerline).
Embedded parts shall be installed in the correct direction. Anchor bolts should be reserved strictly according to the layout design drawings, accurately positioned, and continuously checked and corrected during and after construction. For bridges located on flat or longitudinal slopes, the top surface of the mast foundation should be level, the top surface of the embedded steel plate should be flush with the foundation, and the embedded anchor bolts should be perpendicular to the horizontal plane. The distance error of the top of the anchor bolt deviating from the vertical position should not exceed 1mm.
AGICO also supplies customized fabrication of high-strength anchor Bolts, if you are interested in embedded steel plate solutions, don’t hesitate to send a free quote now!
3 Basic Requirements For Embedded Part Installation
- Spacing and Exposed Length Requirements: The spacing of the embedded bolts in the contact line foundation along the route is 160 mm, and the spacing across the bridge is 430 mm. The M39 anchor bolts embedded in the contact wire support foundation are exposed 190 mm above the foundation surface. The center-to-line center distance error of the bolt group is +5 mm/-0 mm, the center offset error of the bolt group along the line direction is ±50 mm, the exposed bolt length and bolt length error are +5 mm/-0 mm, the adjacent bolt spacing error is ±1 mm, and the diagonal bolt spacing error is ±1.5 mm.
- Corrosion Protection Requirements: Anchor bolts, nuts, washers, and embedded steel plates should all be treated with anti-corrosion coating. Anchor bolts and their exposed portions within 150 mm below the foundation surface should be treated with multi-alloy co-diffusion + Dacola technology + sealing layer. Embedded steel plates should be treated with a multi-alloy co-diffusion + sealing layer.
- Welding Requirements: All grounding reinforcement bars should be lap welded, with a double-sided weld length of not less than 55 mm, a single-sided weld length of not less than 100 mm, and a weld thickness of not less than 4 mm.
