Structural Testing
Red Cliff Bridge LLT
Red Cliff Bridge is a cantilevered steel arch bridge located near Red Cliff, Colorado. Towering approximately 200 ft over Eagle river, it is one of Colorado’s most iconic bridges and has been listed on the National Register of Historic Places since 1985. The bridge was completed in 1941 and has required significant repair and restoration…
Read MoreSitka Bridge
Sitka Harbor / John O’Connell Bridge in Sitka, AK is a historic civil engineering landmark and one of the oldest cable-stayed bridges in the US. Under Alaska DOT’s inspection program, this structure requires a special in-depth inspection every decade. As part of the inspection team, BDI conducted a comprehensive evaluation of the stay cables. Our work included:…
Read MoreRestoring a Critical Link on the Alaska Highway
When a fuel tanker accident caused extensive fire damage to the Sikanni Chief River Bridge—a prestressed concrete bridge along the Alaska Highway in northern British Columbia—swift, expert evaluation was essential to restore safe passage on this key transportation corridor. Therefore, WSP engaged BDI to support the emergency structural assessment efforts following the incident. Our role was…
Read MoreEnhancing Flood Control Reliability at Waterbury Dam
During routine maintenance at Waterbury Dam, the U.S. Army Corps of Engineers (USACE) identified operational behaviors suggesting potential excess resistance in the gates’ trunnion pins. that raised concerns about the performance of the dam’s spillway gates. Given the critical role these gates play in flood control, ensuring reliability of the dam’s spillway gates was essential.…
Read MoreTiger Creek Gates
Tiger Creek Afterbay Dam, originally constructed in 1931, stands approximately 120 feet tall and 400 feet wide. It features ten spillways equipped with steel Tainter gates and is owned and operated by Pacific Gas and Electric (PG&E). BDI had previously performed pin friction testing on these gates in 2015, and returned in 2024 to reassess…
Read MoreSDOT Bascules
Fremont, Ballard, and University Bridge are double-leaf bascule bridges located in Seattle, WA. All three bridges operate frequently, with Fremont in particular being one of the most frequently opened moveable drawbridges in the US. The bridges also have significant historical and aesthetic significant to Seattle, and are all listed on the National Register of Historic…
Read MoreStructural Evaluation of I-81 Bridges Following Concrete Repairs
The Virginia Department of Transportation engaged BDI to perform a comprehensive structural evaluation of two twin reinforced concrete T-beam bridges along Interstate 81 in Smyth County, VA — an essential corridor for heavy truck traffic. After a construction contractor completed concrete repairs, including the application of a latex-modified concrete (LMC) overlay to the bridge decks,…
Read MoreCDOT Load Ratings
The Colorado Department of Transportation (CDOT) required updated load ratings for a series of off-system bridges. In collaboration with Benesch Engineering, BDI conducted load ratings for 36 prestressed concrete bridges in accordance with AASHTO LRFR and CDOT rating specifications. Using AASHTOWare Bridge Rating (BrR) software, BDI delivered efficient and accurate analyses, supporting CDOT’s efforts to…
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