Integral Abutments and Jointless Bridges (IAJB) 2004 Survey Summary

Integral Abutment and Jointless Bridges (IAJB) have been used for decades and the criteria for using them and detailing has varied from state to state. The main advantage of IAJB is the elimination of joints, which after they start leaking, account for 70% of the deterioration that occurs at the end of girders, piers and abutment seats. The Federal Highway Administration (FHWA) promotes the usage of IAJB where appropriate, as one method of building bridges that will last 75- 100 years with minimal maintenance. In 1995 and 1996, FHWA in conjunction with the Constructed Facilities Center (CFC) at West Virginia University (WVU) conducted a survey and workshop about integral abutment bridges. In 2004, another survey was developed by FHWA and the CFC at WVU, using similar questions as the 1995 survey and incorporating additional questions, to obtain a status of usage and design for integral abutments and jointless bridges. The survey was distributed by AASHTO Subcommittee on Bridge and Structures to all 50 state departments of transportation (DOTs), District of Columbia DOT, Puerto Rico Highway and Transportation Authority and Federal Lands Highways Division (referred to as ‘states’ in the paper). This paper summarizes the responses received to date from the states. The survey was divided into different topic areas which included General Issues, Design and Details, Foundation, Abutment/Backfill, Approach Slabs, Retrofit (Jointed to Jointless), and Other Issues. Integral abutments, as defined in the survey and in this paper, refers to the monolithic construction of the abutment with the deck in order to eliminate the joints at the end of the bridge. This includes the use of full, semi-integral abutments and deck extensions. Jointless bridges refers to the elimination of joints at the piers through the usage of integral pier caps, continuous spans and continuous for live load construction. The purpose of the survey was to obtain a snapshot about the usage of IAJB from the states, their policy, their design criteria and other issues. The results of the survey are presented in this paper and will be used to disseminate information between states and help FHWA encourage the usage of IAJB.