Field Performance of a New Approach Slab System

The Louisiana Department of Transportation and Development has initiated a major effort to minimize the bridge end bump problem. As a result, a new design for the approach slab was proposed, which requires increasing the slab rigidity and the use of reinforced soil foundation (RSF) to support the slab and traffic loads. The Bayou Courtableau Bridge was selected as a demonstration project to evaluate and verify the new approach slab design system. The thickness of the approach slab is 16 inch. The end support of the approach slab is a 4.0-feet wide strip footing with soil underneath reinforced by geogrid. The first static load test was conducted right before the bridge opened to the traffic. The test results indicated that the west approach slab (with new design) remained its full contact supports from the soil while the east approach slab (with traditional design) started losing a portion of its supports from the soil.