Zivan Cohen and the late Dick Tadjer established the firm of Tadjer-Cohen Associates, Inc. in 1962 to provide consulting structural engineering services. The firm's success is reflected in completion of design for over forty-six billion dollars of construction in the US and overseas.
From 1977 to 1980 Zivan was an adjunct professor teaching design of structures to the senior class in the Engineering Department at Catholic University of America, Department of Civil Engineering, Washington, DC. He has published papers on structural design and received a national award for excellence in structural design.
Zivan has worked on many projects varying in magnitude and complexity including residential, educational, commercial, parking structures, and industrial buildings; both low and high rise, military installations for the Army and Navy, and government facilities including work at the Pentagon and special type facilities. He has been extensively involved in designs encompassing structural steel, reinforced concrete, pre-stressed and post tensioned concrete, space frames, and investigations and conversions of existing structures. Also, he has conducted structural evaluations of existing structures for renovations and conversions to other uses and upgrading of existing structures, investigated structural failures, and provided expert witness testimony.
Zivan provides supervision and direction from the firm's Silver Spring, MD headquarter's office for Tadjer-Cohen-Edelson Associates and TCE-India.