Bridge Expansion Joint for Bridges with Expansion Joints in Deck Drainage

Bridge deck drainage systems must be integrated with expansion joints to ensure that water is effectively drained from the bridge deck while the joint maintains its waterproofing and structural performance. The integration must accommodate the movement of the joint while maintaining the drainage function. Drainage inlet design at expansion joints must collect water that flows across the bridge deck and direct it to the drainage system. The drainage inlet must be located on the upstream side of the joint to prevent water from ponding at the joint. The inlet must be sized for the design storm flow without ponding. Drainage trough design below the expansion joint collects water that infiltrates the joint and directs it to the drainage outlets. The trough must be sized for the maximum expected water flow, including the flow from the joint waterproofing failure. The trough must be sloped to direct water to the drainage outlets without ponding. Drainage outlet design at expansion joints must direct the collected water away from the bridge structure without causing erosion or corrosion. The outlets must be located to discharge water away from the bridge foundations and the abutment backfill. The outlet pipes must be sized for the maximum expected flow. Debris management in the drainage system at expansion joints requires the drainage inlets and troughs to be designed to prevent debris from blocking the drainage outlets. The inlet grating must be sized to pass leaves, sand, and other debris without blocking. Regular cleaning of the drainage system is required to maintain the drainage capacity. Maintenance of the drainage system at expansion joints requires annual inspection of the drainage inlets, troughs, and outlets. Any blockage must be cleared promptly to prevent water ponding at the joint. Any damage to the drainage system must be repaired promptly to maintain the drainage function.