Pot Bearing with Large Load Capacity and Large Horizontal Displacement

Pot bearing is a kind of new type bearing which is composed of pot, elastomeric pad, stainless steel plate, sealing ring and other components. It is designed for bearing the combinations of vertical loads, horizontal loads, longitudinal and transverse displacements and rotations. Pot bearing is ideal bearing for large bridge with the features of large horizontal displacement, light weight, simple structure and easy operation.

Five components of pot bearing are placed on the white background.

PB-02: The main components of pot bearing.

Working Principle

There is an elastomeric pad in the pot of the pot bearing, it has fluid properties when it in the state of three-phase stressed, making use of this feature can achieve large rotation of the bearing. In addition, when a relative motion occurs between the PTFE plate which placed on the piston and the stainless steel plate, horizontal displacement can be achieved. Pot bearing can meet the requirements of large end reaction, large horizontal displacement and large rotation, it is suitable for the bridge with large span and large end reaction.

 Some workers are working in the workshop for producing pot bearing.

PB-03: The production of pot bearing in the workshop.

Some workers are working in the workshop for collecting pot bearing products and related components.

PB-04: The assembly of pot bearing in the workshop.

Categories

In addition, according to the displacement ability, pot bearing can be divided into three types: fixed pot bearing (GD), guided sliding pot bearing (DX) and free sliding pot bearing (SX). Fixed pot bearing and guided sliding pot bearing can also be divided into common pot bearing and damping pot bearing. The appearance of these pot bearings is similar, but the difference of internal structure directly determines whether the bridge can be displaced.

Fixed Pot Bearing – Rotation Performance Only

Fixed pot bearing consists of top and bottom steel plates, stainless steel plate, piston, brass sealing ring and elastomeric pad. The internal sealing ring enables the piston to rotate under load. This kind of pot bearing has rotation performance but restricts all displacement in planar axis.

One small size square fixed pot bearing on the big round shape fixed bearing, both of them are painted with orange color.

PB-05: Fixed pot bearing can keep the loads between the superstructure and substructure transferring under control.

A diagram of fixed pot bearing which on the white background is help us know its internal structure clearly.

PB-06: Fixed pot bearing has the characteristics of simple structure and light weight.

Guided Sliding Pot Bearing – Rotation performance & one-direction sliding

Guided sliding pot bearing is identical in construction to free sliding pot bearing, but two guides are fixed at the top steel plate for bearing pad movement limitation. It has vertical rotation performance and one-way sliding performance. And there are two kinds of types about this protect: edge guided sliding pot bearing and center guided sliding pot bearing.

Edge guided sliding pot bearing is painted with orange color, the PTFE plate is embedded into steel piston for friction reduction.

PB-07: Edge guide sliding pot bearing can carry the weight of bridge, it is compact and light.

One edge guided sliding pot bearing diagram is shown to help us know its internal structure.

PB-08: Edge guided sliding pot bearing allows one way direction movement.

One center guided sliding pot bearing which has grey color surface.

PB-09: Center guided sliding pot bearing has the same performance as edge guided sliding pot bearing.

One center guided sliding pot bearing diagram is shown to help us know its internal structure.

PB-10: One center guided sliding bearing also allows one way movement.

Free Sliding Pot Bearing – Rotation performance & multi-direction sliding

Free sliding pot bearing has the same structure with the fixed pot bearing, besides there also a PTFE plate above the piston to enable the bearing to slid in all directions. It has vertical rotation, vertical and horizontal sliding performances.

An orange free sliding pot bearing is placed on a small white table.

PB-11: Free sliding pot bearing facilitates rotations and movements in every direction.

One free sliding bearing diagram help us know its internal structure clearly.

PB-12: Free sliding bearing with the PTFE above the piston to overcome high friction and for better movement.

Different model

  • GPZ highway bridge pot bearing

    A schematic diagram of GPZ highway bridge pot bearing with the name of each main components is on the white background.

    PSPB-13: The schematic diagram of GPZ highway bridge pot bearing.

    • Specification

      • Fixed pot bearing
      • Guided sliding pot bearing
      • Free sliding pot bearing
    • Technical parameter

      • Vertical rotation angle of bearing: not less than 40'.
      • Vertical bearing capacity: 1000–50000 kN, it is divided into 28 levels, the horizontal bearing capacity of non-slip surface is 10% of vertical.
      • Friction coefficient

        • Normal temperature type bearing: μ ≤ 0.04.
        • Cold resistant type bearing: μ ≤ 0.064.
  • Table 1: Displacement of GPZ Highway Bridge Pot Bearing

    End Reaction/Type Maximum Displacementthe longitudinal direction of bridge (mm) Maximum Displacementthe transverse direction of bridge (mm)
    GD SX DX GD SX DX
    1000–3000 kN 0 ±50, ±100 ±50, ±100 0 ±5, ±10 0
    3500–9000 kN 0 ±100, ±150 ±100, ±150 0 ±10, ±15 0
    10000–30000 kN 0 ±150, ±200 ±150, ±200 0 ±15, ±20 0
    32500–50000 kN 0 ±200, ±250 ±200, ±250 0 ±20, ±25 0

    Table 2: Physical Properties of Rubber Materials of Bearing

    Item/Rubber Type Neoprene Natural Rubber EPDM
    Hardness (shore A) 60 ± 5 60 ± 5 60 ± 5
    Tensile Strength ≥17.0 ≥17.5 ≥15.2
    Elongation at Break ≥400% ≥400% ≥350%
    Brittleness Temperature ≤-40 °C ≤-50 °C ≤-60 °C
    Constant EN Compression Set(70 °C, 22 h) ≤20% ≤25% ≤25%
    Resistance of Ozone Aging(Test Condition: 25–50 pphm, 20% Elongation, 40 °C, 96 h) no cracking no cracking no cracking
    Air Oven Aging Test Test Condition(°C × h) 100 × 70 70 × 168 100 × 70
    Reduction Rate of Tensile Strength <15% <15% <15%
    Reduction Rate of Elongation at Break <40% <20% <40%
    Change of Hardness <+15 <+10 <+10
  • GPZ (Ⅱ) highway bridge pot bearing

     schematic diagram of GPZ (Ⅱ) highway bridge pot bearing with the name of each main components is on the white background.

    PB-14: The schematic diagram of GPZ (Ⅱ) highway bridge pot bearing.

    • Specification

      • Fixed pot bearing
      • Guided sliding pot bearing
      • Free sliding pot bearing
    • Technical parameters

      • The actual bearing capacity of the pot bearing is 100% of the design bearing capacity, and it allows an overload of 10%.
      • When the pot bearing is between -25 °C and 60 °C, the minimum value of the design friction coefficient is 0.03; when it is between -40 °C and 60 °C, the minimum value of the design friction coefficient is 0.06.
      • The design maximum rotation angle of the pot bearing is 0.02 rad.
  • GPZ (Ⅲ) highway bridge seismic pot bearing

    A schematic diagram of GPZ (Ⅲ) highway bridge seismic pot bearing with the name of each main

    PB-15: The schematic diagram of GPZ (Ⅲ) highway bridge seismic pot bearing.

    • Specification

      • Fixed pot bearing
      • Guided sliding pot bearing
    • Technical parameter

      • Design bearing capacity of pot bearing: 0.8–60 MN, it is divided into 31 specifications.
      • Rotation angle of pot bearing: 0.02 rad.
      • Design friction coefficient of guided sliding pot bearing (condition: anti-seismic bearing, non-earthquakes, add grease)

        • Normal temperature type bearing: the minimum value is 0.03.
        • Cold resistant type bearing: the minimum value is 0.06.
      • Horizontal force of bearing: seismic fixed pot bearing in all direction and seismic guided sliding pot bearing in non-slip direction is 20% of design bearing capacity.
  • GPZ (KZ) highway bridge seismic pot bearing

    A schematic diagram of GPZ (KZ) seismic pot bearing with the name of each main components is on the white background.

    PB-16: The schematic diagram of GPZ (KZ) seismic pot bearing.

    • Specification

      • Fixed pot bearing
      • Guided sliding pot bearing
      • Free sliding pot bearing
    • Technical parameter

      • Design reaction of bearing (vertical bearing capacity): 0.8–60 MN, it is divided into 31 specifications.
      • Horizontal bearing capacity

        • The horizontal bearing capacity of fixed pot bearing in all directions is equivalent to 20% of the design reaction.
        • The horizontal bearing capacity of guided sliding pot bearing in the direction that perpendicular to the bridge is equivalent to 20% of the design reaction.
      • Rotation angle of the pot bearing: the design rotation angle of pot bearing is 0.02 rad.
  • Table 3: Displacement of GPZ (KZ) Seismic Highway Bridge Pot Bearing

    Specification/Type Maximum Displacement the longitudinal direction of bridge (mm) Maximum Displacement the transverse direction of bridge (mm)
    GD SX DX GD SX DX
    0.8–3 0 ±50, ±100, ±150 ±50, ±100, ±150 0 ±40 ±3
    3.5–9 0 ±100, ±150, ±200 ±100, ±150, ±200 0 ±40 ±3
    10–30 0 ±150, ±200, ±250 ±150, ±200, ±250 0 ±40 ±3
    32.5–60 0 ±200, ±250, ±300 ±200, ±250, ±300 0 ±50 ±3
  • GPZ (2009) pot bearing

    A schematic diagram of GPZ (2009) pot bearing with the name of each main components is on the white background.

    PB-17: The schematic diagram of GPZ (2009) pot bearing.

    • Specification

      • Fixed pot bearing
      • Guided sliding pot bearing
      • Free sliding pot bearing
    • Technical parameter

      • Design bearing capacity of pot bearing: 0.4–60 MN, it is divided into 33 levels.
      • The vertical curve inner rotation angle: 0.02 rad, and it adapts to any rotation angle in horizontal curve.
      • The horizontal force that the bearing can withstand: the horizontal force of fixed pot bearing in all directions and guided sliding pot bearing in one direction is 10% of the vertical bearing capacity.
      • Design friction coefficient of pot bearing

        • Normal temperature (-25°C to 60°C): μ ≤ 0.03.
        • Cold resistant (-40°C to 60°C): μ ≤ 0.06.

Feature

  • Providing longer service life compared to elastomeric bearing pad.
  • Large horizontal displacement and large bearing capacity.
  • Accommodate rotations at any axis and the appropriate movements of the bridge.
  • Totally detachable, and easy to dismantle if any element has to be replaced.
  • Saving steel and reduce costs.

Specification

  • Material: steel, elastomer.
  • Shape: round and rectangular.
  • Hardness (shore A): 55–65.
  • Capacity: 1000–70000 kN.
  • Displacement: 0–300 mm.
  • Normal temperature type bearing: suitable for -25 °C to 60 °C.
  • Cold resistant type bearing: suitable for -40 °C to 60 °C.
  • Certification: CCC, SGS, CE, ISO.
  • Package: plastic, wooden or tin box.
Several pot bearings are wrapped with plastic and placed neatly on the ground.

PB-18: Pot bearings are packaged with plastic.

A pot bearing is packaged in plastic film and  reinforced with wooden box.

PB-19: Pot bearing in the wooden box.

Application

Pot bearing is mainly used in such fields

  • Bridge which the structure with rotations in various directions.
  • Large curved or skewed bridge.
  • Highway.
  • Other fields which also need to meet the need of large load and rotation.
An orange guided sliding pot bearing is connected the bridge deck and the bridge pier.

PB-20: Guided sliding pot bearing is used for bridge.

A long highway is supported by pot bearings.

PB-21: Pot bearings are used for highway.

Two workers which are wearing orange overalls are installing pot bearing on the bridge.

PB-22: The installation of pot bearing.