Expansion Joint Design for Integral Bridges: Eliminating Joints on Short-Span Bridges

Integral bridges eliminate expansion joints entirely by making the deck continuous with the abutments. This approach is increasingly popular for short-span bridges due to lower maintenance costs. What is an Integral Bridge: An integral bridge has no expansion joints at the abutments. Thermal movement is accommodated by abutment rotation (for short spans), soil pressure behind abutments, and approach slab movement. Applicable Span Limits: UK BD 57/01 allows up to 60m total length (steel) and 40m (concrete). AASHTO allows up to 100m (varies by state). Eurocode has no specific limit, but typically <150m. Advantages of Integral Bridges: No expansion joints means no joint maintenance. No bearings at abutments (for fully integral design). Improved structural redundancy. Better seismic performance. Lower whole-life cost. When to Use Expansion Joints vs Integral Design: For spans <60m consider integral design (lower whole-life cost). For spans 60-200m expansion joints are typically required. For spans >200m modular expansion joints are essential. Transition Zones: Where expansion joints are unavoidable, transition zones with approach slabs and sleeper beams minimize differential settlement and joint impact loads.