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Type of pier column connection with superstructure

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Piers are important portion of bridge substructure. piers are transferring the dead load of the superstructure and the loads supported by superstructure such as live load and stresses induced by the change of superstructure length due to temperature change, creep and shrinkage to bridge foundation. piers can have a different cross-sectional shape. the photo below showing some typical cross-sections for piers.








there are different types of pier such as: hammer head, soild wall pier, rigid frame pier and column bent pier. selecting a pier type will be controlled by site condition and design consideration







Type of pier column connection with a superstructure:
  • monolithic connection: in this type of connection the piers are casted monolithically with the superstructure. steel reinforcement from pier will be extended inside the bridge diaphragm or web. in this type of piers the movement of the bridge are restrained and this will cause internal stresses om the structure.
  • bridge bearing connection: in this type of connecting bearings are used to connect piers with a superstructure. elastomeric, pot and spherical bearings are used widely in bridge industry. the bearing will release the stress-induced by changing structure length due to temperature, shrinkage, and creep by rotation and translation movement in both directions. but bridge bearing required periodic inspection and maintenance. this will increase the cost of bridge construction and will cause inconvenience for road commuters in the event of road closure for inspection or bearing maintenance 




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