Briefly describe the characteristics of spherical bearings for railway rail transit bridges
The spherical bearing of railway rail transit bridges is a key load-bearing component that connects the upper and lower structures of the bridge. It is designed to adapt to the load characteristics, displacement requirements, and vibration environment of railway bridges. Its core features are as follows:
The spherical bearing of railway rail transit bridges is a key load-bearing component that connects the upper and lower structures of the bridge. It is designed to adapt to the load characteristics, displacement requirements, and vibration environment of railway bridges. Its core features are as follows:
1. Strong load-bearing capacity
Adopting a spherical contact force transmission structure, it can uniformly transmit vertical loads (including dead loads, live loads, and impact forces) of the upper structure of the bridge, and can adapt to large tonnage load scenarios such as high-speed railways and heavy-duty railways, ensuring stable force transmission.
2. Multi directional displacement adaptability
By utilizing the relative rotation between the spherical crown and the spherical lining plate, the bridge can achieve free displacement and rotation in the horizontal direction (longitudinal and transverse), meeting the displacement requirements caused by temperature changes, concrete shrinkage and creep, train braking, etc., and avoiding additional stress on the structure.
3. Flexible rotation and wide angle range
The spherical contact design reduces rotational friction resistance and allows the upper structure of the bridge to generate large turning angles (usually up to 0.02~0.05 rad), especially suitable for scenarios with large turning angle requirements such as curved bridges and skew bridges.
4. Excellent seismic performance
Some spherical supports are equipped with shock absorbers (such as polytetrafluoroethylene sliding plates and elastic cushion layers), which can absorb some seismic energy through sliding or elastic deformation during earthquakes, limit excessive displacement of the beam, and protect the safety of the bridge structure.
5. Good wear resistance and durability
The key contact surfaces are made of wear-resistant materials (such as stainless steel plates and polytetrafluoroethylene) to reduce friction losses; The sealed structure can prevent dust and rainwater from entering, adapt to the harsh environment of long-term outdoor service of bridges, and extend their service life.
6. Convenient maintenance
The design of the support structure facilitates the inspection and replacement of vulnerable components such as skateboards and sealing rings, allowing for maintenance without interrupting driving and reducing operating costs.