Dive summary:

• The new $6.4 billion San Francisco-Oakland Bay Bridge, slated to open this fall, likely is getting replacements for at least 32 of the steel connecting rods that make up part of the self-anchored suspension design because the threaded rods broke when crews began to tighten nuts to add tension.
• The concrete-encased bolts, which are 3 inches in diameter and vary from 9 to 24 feet long, attach to shear plates that are part of the design for avoiding earthquake damage to the new, double-decker span – though they are not considered structural components, there may be alternatives to getting them out and putting in new ones.
• Officials blame hydrogen contamination in the steel used to forge the 288 bolts that were installed in 2008 and of which 100 have been tensioned so far with the 32% failure rate.

From the article:

The rods are located in the gap between the easternmost pier of the 2,047-ft SAS span and the 35,200-ton overhead road deck. ...