The magnitude-5.8 earthquake that rattled most of the eastern U.S. on Aug. 25 created new cracks and spalling in the upper sections of the 555-ft, 5-in.-tall Washington Monument in the nation's capital. While the extent of quake-related damage was not a surprise, the size of several spalls was larger than expected, says a forensic engineer who conducted an inspection for the U.S. National Park Service.
The survey team of Wiss, Janney, Elstner Associates Inc., Northbrook, Ill., extracted any spalls that represented a potential fall hazard and could be safely removed. The largest piece eliminated, at the southeast corner just below the monument's 55-ft-tall pyramidion, weighs 30 to 40 lb. The team also removed portions of some repairs, loosened by the quake, made during the obelisk's first full-scale renovation, completed in 2000 (ENR 7/10/00 p. 11).