Bottom floor gets top priority in IRS project

摘要

When the Building Team began the $60.7 million ren- ovation and modernization of the 1.4 million-sf Internal Revenue Service headquarters in Washington, it was obvious where to start. Sections of the building's slab-on-grade basement floor were sinking. The initial deflection, which involved an area of 15 by 25 feet, later spread to other sections of the 186,000-sf slab. The failures were caused by underground voids, ranging in depth from two inches to as much as three feet, that resulted from settlement and consolidation of the subsoil. The slab failure cracked underground piping, which had to be replaced. New underground storm, sewer, and subsoil drainage was installed.