
Past IREF Chairman Van Zelst Retires
Theodore W. Van Zelst, an honorary lifetime member of IRF, has officially announced his retirement from the IREF board, after more than five decades of service.
In 1948 Van Zelst co-founded Soiltest Inc., which became the world’s largest provider of materials testing equipment for soil, rock, concrete, and asphalt. His impressive list of accomplishments includes devising the swing-wing design that enabled supersonic aircraft to penetrate the sound barrier, developing the first mobile baggage inspection unit, and planning lunar construction and soil testing years before Neil Armstrong set foot on the moon.
Van Zelst served as chairman of IREF in 1978 and has remained active throughout his life promoting educational opportunities, especially for young engineers. Through various positions on both the IRF and IREF Boards, he worked his IRF colleagues to expand the Fellowship Program, increase the amount of scholarships awarded, and earnestly sought after private sector donations to the IREF endowment fund.
IRF expresses its utmost gratitude for Mr. Van Zelst’s years of service. His influence and legacy will continue on in the IRF Fellowship program and the thousands of Fellows who are a part of this special program.
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