A MODIFIED PLASTIC THEORY OF REINFORCED CONCRETE PAUL ANDERSEN, Ph.D. Professor of Structural Engineering HWA-NI LEE, Ph.D. Formerly Instructor, Department of Mathematic and Mechanics • BULLETIN NO. 33 UNIVERSITY OF MINNESOTA J. L. MORRILL, President INSTITUTE O,F TECHNOLOGY A. F. SPILHAUS, Dean ENGINEERING EXPERIMENT STATION R. E. MONTONNA, Director VOL LIV NO. 19 APRIL 16 1 1951 Entered at the post office in Minneapolis as semi-monthly second- class motter, Minneapolis, Minnesota. Accepted for moiling at special rote of postage provided for in Section 1103, Act of October 3, 1917, authorized July 12, 1918.