Subcommittee on Design, Material Characterization, and Performance Evaluation of Concrete with Admixtures (Subcommittee 333)

Recently, the increased awareness of low environmental impacts and efficient resource utilization has resulted in a high necessity for applicability of admixture material. For this reason, the 333 committee was established and started its activities since September 2004, aiming to clarify the relationship among various mineral/chemical admixtures, concrete quality and its performance. The research activities was proceeded from the viewpoint of actual investigation, mechanisms elucidation, and performance investigation based technology and design on physical changes and performance evaluation of the concrete with admixtures. In March 2007, the committee issued a report and held a symposium on the outcome of overall activities during the 2 years of the first session.

At the moment, the 333 committee has entered the second session in order to advance the previous session's activities by analyzing in detail the actual results (initial cracking, durability, etc.) obtained from investigating concrete structures made with various mineral/chemical admixtures and characterization of concrete with advanced technology. In addition, we are also aiming at systematic design methodology for the performance investigation technology.

In March 2008, we held an international workshop on Material Characterization, Design, and Performance Evaluation of Concrete with Admixtures at Tsinghua University (Beijing, China), which focused on overall results from the first session and activity objective for the next 2 years of the second session. At the workshop opening, Prof. Nawa Toyoharu as the head committee of the 333 committee, had stated that efficient use of admixtures is of great importance in order to achieve high quality concrete structures while reducing the environmental impacts, and that we need to clearly understand the concrete performance evaluation and mechanism of admixture reaction. Seven keynotes lectures were provided at the workshop. First, Prof. W. Qin from Tsinghua University gave an introduction on the current situation of infrastructures maintenance, concrete and admixtures usage in the growing China, which attracted interests from the participants who are in the construction industry. Next, Prof. X. An from the same Tsinghua University introduced the application of SCC (Self-compacting concrete) technology, which was developed in Japan, to dam construction in China.Subsequently, Irie from KEK introduced the topic on current situation of admixtures usage in Japan . The presentation was followed by the review on applications of admixtures in Europe and its outlook in the future by Dr. E. Gartner from Lafarge. He also introduced his own chemical admixtures that are currently being studied. The presentation was followed by the topic on material design methodology from the environmental impact reduction viewpoint by Prof. Nawa. Prof. Umemura introduced the discussions on material characterization technique as a committee activity, and Dr. Ishida presented his own numerical model as a promising technology to deal with concrete performance with admixtures. Fourteen technical presentations were subsequently given. Lively discussions on the admixtures took place among the researchers from around the world.

Workshop on Material Characterization, Design, and Performance Evaluation of Concrete with Admixtures, March 1-4, 2008, Tsinghua University, Beijing, China.