Fatigue Cracking in the Sprague Street Bridge

The Sprague Street Bridge is located in the Hyde Park Section of Boston, Massachusetts. The bridge was built in 1898 and consists of two simple spans each 68.580 meters long composed of Baltimore type steel thru trusses supporting a corrugated metal deck filled with asphalt. In the late 1990’s the Massachusetts Highway Department (MHD) ask the author to evaluate the structure to determine if it were feasible to rehabilitate the structure to meet current load standards. Of particular concern for MHD was determining the cause of: 1. Cracking and excessive vibration in the midspan eyebar diagonals; 2. Cracking in the webs of some floorbeams that started to occur soon after a major rehabilitation project in the late 1980s. By performing an in-depth visual inspection which included material testing and reviewing available inspection reports, estimating the number of load cycles the structure had undergone since its construction in 1898, calculating crack growth, and analyzing the structure’s behavior under loading, the author was able to conclude: 1. Excessive vibration of the diagonals was due to a design flaw in the original bridge design and rehabilitation mistake. 2. The floorbeam webs were cracking due to a rehabilitation design mistake. This case study will illustrate how to evaluate a truss structure for fatigue problems and how to avoid creating new problems during rehabilitation. Considering the number of very old and historic bridges that will need to be preserved for future generations, the devil will always be in the details.

• Corporate Authors:

  Lehigh University

  ATLSS Engineering Research Center, 117 ATLSS Drive
  Bethlehem, PA  United States  18015
• Authors:
  • Krajewski, J E
• Conference:
  • First International Conference on Fatigue and Fracture in the Infrastructure: Bridges and Structures of the 21st Century
  • Location: Philadelphia Pennsylvania, United States
  • Date: 2006-8-6 to 2006-8-9
• Publication Date: 2006-8

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures; References; Tables;
• Pagination: 23p
• Monograph Title: First International Conference on Fatigue and Fracture in the Infrastructure: Bridges and Structures of the 21st Century

Subject/Index Terms

• TRT Terms: Bridge design; Cracking; Inspection; Materials tests; Rehabilitation; Repeated loads; Steel; Structural analysis; Traffic loads; Truss bridges; Vibration
• Subject Areas: Bridges and other structures; Design; Freight Transportation; Highways; Maintenance and Preservation; I24: Design of Bridges and Retaining Walls; I60: Maintenance;

Filing Info

• Accession Number: 01091770
• Record Type: Publication
• Files: TRIS
• Created Date: Apr 23 2008 9:27AM