Have an attendance code? Sign In to enter it. This live web event has ended. Thank you for attending. Contributors F. Dirk Heidbrink, P.E. F. Dirk Heidbrink, P.E., is a civil engineering graduate of Purdue University and an Associate Principal with Wiss, Janney, Elstner Associates, Inc. (WJE) in Northbrook, Illinois. During his 39-year tenure at WJE, Mr. Heidbrink has conducted hundreds of load tests using a wide variety of load mediums on existing structures. He is an active member of ACI Committee 437 and a member of the subcommittee that developed the current load test specification referenced in ACI 562-16 “Code Requirements for Assessment, Repair, and Rehabilitation of Existing Concrete Structures” and to be referenced in the next revision of ACI 318 “Building Code Requirements for Structural Concrete”.