Which joint type can accommodate total motion ranges between about 45 mm and about 130 mm?

• A. Small movement joints
• B. Bridge expansion joints
• C. Rubber joints
• D. Medium movement joints

Answer: (D)

Understanding how joint movement is categorized helps explain why this range fits a medium movement joint. Bridge joints are designed to accommodate the amount of deck movement caused by temperature changes and traffic loads. A movement range of about 45 mm to 130 mm represents a moderate amount of expansion and contraction, placed in the mid-range category. Medium movement joints are specifically intended for this level of movement, balancing sealing, durability, and ease of installation for that span of motion.

Small movement joints handle much less movement, so they’re not suited for 45–130 mm. Rubber joints are mainly used for flexible sealing and cushioning and generally aren’t specified for such large moves. Large or expansion joints cover greater movements, exceeding the 130 mm upper limit in many designs. Therefore, the joint type designed for this 45–130 mm range is the medium movement joint.