State departments of transportation (DOTs) use many different details to make the transition between roadway pavement and bridges. Typically, a section of bridge approach pavement is a specialized pavement area that is reinforced to act as a “jump span” between the roadway pavement and bridge. The bridge approach pavement may be supported by the subgrade or sleeper slabs on the roadway side and by a support corbel on the bridge side. In some cases, the approach pavement is mechanically connected to the bridge and in other cases, it is free to move independently of the bridge. Various joint details may also be used where the bridge approach pavement meets the bridge.
The details used in this area must be designed and constructed appropriately to be durable, to remain as maintenance free as possible, and to provide a smooth transition from the roadway and bridge. Additionally, water management is a key consideration for the transition from the bridge to the approach pavement. Water running off of the bridge without appropriate transition details may lead to substructure deterioration, foundation deterioration, and undermining of the bridge approach pavement or bridge substructure. Pollution prevention may also be a consideration requiring water to be captured and appropriately dealt with. While DOTs have their own design and construction practices for bridge approach systems, agencies continue to experience inconsistent bridge approach performance.
The objective of this synthesis is to document DOT practices related to bridge approach systems. The synthesis will focus on documenting practices shown to provide smooth ride, long life, and minimal maintenance.
Information to be gathered includes (but is not limited to):
• Approach slab design criteria and standards, including approach pavement and supporting elements;
• Performance criteria for bridge approach systems (e.g., surface smoothness, joint selection and performance);
• Practices related to tying the approach slab to the bridge abutment;
• Geotechnical considerations for settlement and compaction of backfill material;
• Drainage issues and mitigation practices (i.e., water management);
• DOT prioritization of major performance issues; and
• DOT effective practices
Information will be gathered through literature review, a survey of DOTs, and interviews with selected agencies for the development of case examples. The survey should be directed to voting DOT members on the AASHTO Committee on Bridges and Structures. Knowledge gaps and suggestions for research to address those gaps will be identified.
Information Sources (Partial):
Jo Allen Gause
First Panel: September 12, 2019, Washington, DC
Teleconference with Consultant: October 4, 2019, 2:00 p.m., ET
Second Panel: May 19, 2020, Washington, DC
Leo L. Fontaine, Connecticut DOT
Mary Jane Hayden, Florida DOT
Michelle R. Mann, New Mexico DOT
James S. Nelson, Iowa DOT
Anil K. Patnaik, University of Akron
Paul A. Rowekamp, Minnesota DOT
Brian L. Schleppi, Ohio DOT
Jennifer E. Nicks, Federal Highway Administration
Stephen F. Maher, Technical Activities Division