In the aftermath of Tuesday's 5.8-magnitude earthquake in Virginia, building owners in the Washington, D.C., region are accessing potential damage to buildings.
Other industry voices are questioning whether the temblor, the largest Virginia has experienced on record, will lead to new discussions of Seismic codes for the East Coast.
Several major facilities are closed while teams of engineers inspect structures. Most notably, the National Parks Service closed the Washington Monument indefinitely after teams discovered cracks near the top of the 555-ft-tall obelisk, considered the world's tallest of its kind. Other closed facilities include the National Building Museum, the Dept. of Homeland Security building and the Dept of Agriculture's Whitten, South and Yates building. The Dept of Interior closed its main building and its South building for testing.
The National Cathedral also suffered damage to three of its four pinnacles on the central tower. Some of the flying buttresses also suffered major cracks, particularly around the historic apse at the building's east end. Despite the damage, assessments indicate that the cathedral is structurally sound, according to a spokesperson.
Jerry Rasgus, head of the D.C. office for structural engineering firm Weidlinger Associates, says that buildings in the Washington area “performed exceedingly well.” Weidlinger is among the firms that have conducted inspections following the earthquake. Rasgus declined to name the specific clients.
Although no major catastrophes occurred, Rasgus says the earthquake reignites concerns about seismic codes in the region.
“We anticipate that building codes will now require a higher level of force to be included in the overall seismic design of the buildings,” he says.
Although buildings constructed in the District since 1960s have been required to follow seismic codes, Rasgus says older buildings did not and limited efforts have been made to reinforce many of the region’s historic structures. Most of the buildings that were closed for inspections dated from the early 1900 and are built in stone, brick and mortar, he noted.
The U.S. General Services Administration, which is the area’s largest building owner, follows a combination of local codes and international building codes for new construction. For existing structures, GSA follows the Federal Standards of Seismic for Safety of Existing Buildings, which was developed by the Interagency Committee on Seismic Safety in Construction and the National Institute of Standards and Technology.
Dr. Michio Kaku, a professor of physics at City College of New York, has called the quake "a wake-up call" to the East Coast to prepare for a "100-year quake" event. In an interview with Bloomberg Television, Kaku pointed to the meltdown that hit Japan's Fukishima nuclear plant after a tsunami struck the nation in March. The recent quake in Virginia serves to remind us that even in North America and the Northeast, we will have these events, he said. "Nuclear power plants [in the East Coast] have to be braced to handle these kinds of 100-year earthquakes."