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Technical forum of 2015 concrete engineering technical experts committee
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Science and Technology Forum of Concrete Engineering Technology Expert Committee in 2015 organized by CCPA Ready-mixed Concrete Branch was held in Chengdu of Sichuan in the morning of December 14, 2015. It is one of sub-forums of 2015 China Concrete and Cement Product Industry Conference.

The forum is presided by Qi Guanghua-General Manager of Technology Department in China West Construction Group Co., Ltd. In the forum, Qi Guanghua and Ma Zhihua were additionally selected as vice chairmen of concrete engineering technology expert committee, Yu Dingxin, Liang Jun, Chu Jianping, Yang Jinfeng, Liu Junhui, Yu Yujun, Mo Liwu, Li Hongbing, Luo Jinyuan, Mao Haiyong, Le Ci, Shen Wenzhong and Zuo Kewei were additionally selected as members of the expert committee.

Report exchange stage was started in the forum then. Professor Qin Weizu from Tsinghua University made a report 'Innovation and Effect Enhancement of Durable Concrete Mix Proportion Design and Optimization'. Prof. Qin pointed out that the following idea is wrong: concrete durability can be controlled by controlling water-binder ratio. It is more important to control crack by water dosage rather than water-binder ratio. Binding material dosage can be correspondingly reduced under the condition of keeping the same strength when water dosage is reduced, therefore concrete temperature shrinkage, own shrinkage and dry shrinkage can be reduced. Therefore, the standards of selecting concrete mix proportion must be further changed greatly in order to obtain high durability.

Professor Qin analyzed that the quality of the gravel aggregate can be improved by reducing concrete water dosage and increasing gravel dosage aiming at gravel aggregate, binding material dosage with worse volume stability should be correspondingly reduced, thereby improving various performance of concrete on one hand, lowering cost of concrete producers and users on the other hand, gravel aggregate industry, concrete industry and engineering construction career can be more energy-saving and environment-friendly and greener, and sustainable development can be truly realized.