Abstract
Engineers working at a ready-mixed concrete factory have little opportunity to study mixture design of concrete due to developed technologies and shortage of workers. The lack of knowledge of mixture-designing should be concerned especially for young concrete-engineers. The foci of the present study are to reeducate fundamental mixture-design method and to develop an effective education program for young engineers. To study properties of former concrete, river aggregate was employed and a competition of mixture design for the concrete was conducted. The educative competition confirmed that practiced engineers have more superior skill to modify concrete design than young engineers. A questionnaire survey after the competition shows that the education method for the young engineers should be modified to learn the skill and experiences from skilled engineers.
