Precast Prestressed Concrete Pavement to Abate Settlement Problems Under Bridge Approach Slabs (FHWA-OK-16-08 2265)
Abstract
The well-known bump-at-the-end-of-the-bridge often involving the joint between a bridge approach slab (BAS) and a bridge deck (as well as the associated slab cracking) has been a recurring issue over the years in many states. DOTs have reported differential settlement and cracking issues at this joint which has significantly reduced ride quality. Previous experience indicates that any Ònon-removalÓ conventional method of repair would not work well once erosion has set in; however, removing and replacing distressed BAS with cast-in-place (CIP) concrete usually require significant amount of time for curing, which leads to high costs of lane-closure and user delays. Therefore, a long-lasting and rapid repair method is needed to address this issue. This research focuses in part on the introduction of the precast concrete pavement slab for repairing distressed BASs and the elaboration of the design and construction procedures for precast BASs. Key elements within a BAS system are identified and design considerations provided for these elements for the prevention of erosion damage that may occur underneath the BASs. In addition, this research also provides a detailed design procedure for the stone column technique in order to address the potential for large settlement in the foundation of bridge embankments and proposes a procedure using non-destructive testing methods to rapidly characterize soil properties. This report contains three parts. The first part, ÒFinal ReportÓ, consists of Chapter 1 through Appendix D; the second part, from Chapter 9 to Appendix H, is the ÒBridge Approach Design GuidelineÓ; the third part is the ÒStone Column and Embankment Design GuidelineÓ which consists of Chapter 14 to Appendix N.