Bridge Expansion Joint

Construction Process

1. Cutting and crushing down the determined width of overlaid asphalt pavement to expose the bridge deck.

2. Cleaning the channel with pressured air and attaching tape at both sides:

- After removing fragments, dust, small amounts of moisture, and adhered extrangeous substances, attach tapes at both right and left sides of the channel leaving a space.

3. Heating the channel and installing back-up rod:

- After heating the channel with heat-lance the obtain the sufficient temperature (keep about 70 ), install back-up rod.

4. First coating and installing steel support plate:

- Coat the channel with sealant (2mm~3mm thick) and put steel support plate (thickness: 4~8mm) over the center of the joint gap.

5. Filling up the channel:

- Coat the steel support plate again with sealant and the interior surfaces of the channel.

- In the case of the expansion joints, mix heated aggregate (5mm~25mm) with sealant in the volume ratio of 60: 40 (in the weight ratio of 75: 25 (aggregate: Sealant)) and fill this mixture into the channel 1 or 3 times according to its depth. The thickness of a mixture layer is about 5 to 10cm. Also, you must spread sealant between the mixture layers.

6. Finishing:

- Level off the top surface of the joint using heated squeezer or roller and cool it by sprinkling lime or talc powder over. It takes about 1~2 hours for vehicles to pass over newly completed joint