Which joint type can consist of two steel plates sliding on top of one another with a maximum movement of 4 inches?

Which joint type can consist of two steel plates sliding on top of one another with a maximum movement of 4 inches?

• A. Strip seal
• B. Compression joint seal
• C. Pourable joint seal
• D. Assembly joint without seal

Answer: (D)

This question is testing which bridge movement joint design allows two steel plates to slide past each other with a relatively large, unobstructed clearance. An assembly joint without seal fits this description best. It is simply two steel plates with a gap between them and no sealing material or bonded filler. Because there’s no sealant to compress or deform, the plates can move independently relative to each other, enabling sliding movement up to about four inches. The other joint types—strip seal, compression joint seal, and pourable joint seal—use sealants or filled materials to maintain watertightness and accommodate movement, but that sealing hardware typically constrains how far the plates can slide before the seal would fail or require servicing. So while they allow some expansion and contraction, they aren’t designed for the same sliding range as an assembly joint without seal, making the unsupported, unsealed design the correct choice for a 4-inch movement.

This question is testing which bridge movement joint design allows two steel plates to slide past each other with a relatively large, unobstructed clearance. An assembly joint without seal fits this description best. It is simply two steel plates with a gap between them and no sealing material or bonded filler. Because there’s no sealant to compress or deform, the plates can move independently relative to each other, enabling sliding movement up to about four inches.

The other joint types—strip seal, compression joint seal, and pourable joint seal—use sealants or filled materials to maintain watertightness and accommodate movement, but that sealing hardware typically constrains how far the plates can slide before the seal would fail or require servicing. So while they allow some expansion and contraction, they aren’t designed for the same sliding range as an assembly joint without seal, making the unsupported, unsealed design the correct choice for a 4-inch movement.