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24 CHAPTER THREE RESULTS OF SURVEY This chapter summarizes the findings of the survey. One of types of failures, whether they were the result of fatigue the objectives of this survey was to gather information on and fracture or for other reasons (e.g., impact, overload, or fracture-critical structures and how bridge owners define, corrosion). This section also differentiated between failures identify, inspect, and manage FCBs. Information related that occurred before and after the FCP was initiated (around to structural failures and how owners have addressed or 1975 for most agencies) and before and after the FCB inspec- developed retrofit policies and strategies was also collected. tion program became regulation (around 1988 for most agen- In addition, what owners see as the most relevant research cies). Part IV (Retrofit Procedures) contained a series of needs related to FCBs was solicited. questions that sought to acquire information about how own- ers deal with failed bridges and/or subsequently develop pro- Specifically, the survey was intended to collect data in cedures to improve redundancy. This section also requested varying levels related to the following: that individuals provide opinions on future research needs related to FCBs. How FCMs are presently defined, documented, and managed; Overall, the response to the survey was reasonably thor- Inspection frequencies and procedures; ough. After it was sent out, several owners indicated that they Methods for calculating remaining fatigue life; did not have the ability to retrieve the data requested with Qualification and training of inspectors; respect to the breakdown of the structure types that were clas- Available and needed training; sified as FCBs in their inventory. This was the result of limi- Locally owned bridges; tations of the software that they used to manage their bridge Experience with FCM fractures and problem details; databases. Most however were able to provide the detailed data, Examples of where an inspection program prevented which are included in Appendix B. A list of survey respondents failures; is included in Appendix C. Cost of inspection programs; Retrofit techniques used; Two states, Pennsylvania and Oklahoma, provided addi- NDE methods used; tional documentation that described their general inspection As-built versus as-designed; procedures. [More information can be found on the website Fabrication methods and fabrication inspection; and of each state (http://www.dot.state.pa.us/ and http://www. Impact of staff turnover. okladot.state.ok.us/).] According to the document provided, the procedures used by Oklahoma are based somewhat on those of the Pennsylvania DOT. That document provides BACKGROUND guidance on how to prioritize FCBs for inspection criteria A detailed questionnaire intended to identify and characterize and intervals based on remaining fatigue life, fatigue detail, specific issues related to FCBs was developed and distributed material properties, and so forth. to all state and Canadian provincial DOTs and various other transportation authorities within the United States. The sur- In addition, issues related to FCBs were discussed with sev- vey was divided into four parts. Part I (General) collected eral colleagues, the project panel, AASHTO T-14 at the July general information related to FCBs and was the screening 2003 meeting in Baltimore, and participants at the FHWA portion of the survey to determine whether participants should FCB workshop held in Orlando in November 2004. Many of continue on to the other three sections. Part II (Inspection the comments from these conversations are also reported and Classification) was intended to identify the policies and here as anecdotes. approaches used to inspect FCBs. In addition, this section also requested specific data related to the classification and SUMMARY OF RESPONSES TO PART I--GENERAL number of FCBs in an owner's inventory. Part III (Failures) requested specific details about each owner's experiences In this section, agencies were asked to provide their definition with respect to problems with both FCBs and non-FCBs. of an FCB. For the most part, the responses were consistent Owners were requested to provide information about all and nearly all agencies referred to or quoted the definition