By GABRIEL D. REISNER, PE, President, WMA Consulting Engineers, Ltd. Chicago, Ill. ePaul Center, occupying the east side of the 300 block of Chicago’s South State Street, is the new cornerstone of DePaul Univer- sity’s Loop Campus. This large renovated and upgraded multi-	use facility contains classrooms, offices for both the university and tenants, and a two-level retail area known as the Music Mart, which is devoted to the sale and repair of musical instruments and related goods and services. In No- vember 1989, prior to renovation, the building was listed on the Na- tional Register of Historic Places.      DePaul is the largest Catholic university in the Midwest. It has numerous campuses/facilities within the city and surrounding suburbs, and fans of college bas- ketball will recognize the name DePaul Blue Demons. (For more information on the school, see the accompanying sidebar.)      Previously, this newest addi- tion to the university was well known to generations of Chicago- area shoppers, bearing a succes- sion of famous names in depart- ment store retailing. The 11-story structure (plus three below-grade levels) was built in 1912 by A. M. Rothschild & Co. Marshall Field & Co. acquired the property in 1923 and occupied it until 1936. From 1936 until 1981, it was owned by Goldblatt Brothers and was known to its many customers as Goldblatts.      The City of Chicago purchased the building in 1981. Various uses were considered for it, including conversion to a new public library. The property remained vacant, however, until purchased by De- Paul in 1991. The university al- ready had two other facilities along Jackson Boulevard immedi-