一种21世纪最新型的混凝土添加剂（中英文）

lcl999

The first generation of self-compacting high fluidity concretes (SCC) were based on polycarboxylate high range water reducers with cellulose ether technology to control rheological problems; and introduced in the 1970s.
The second generation of SCC was based around new,purpose made high performance polycarboxylate highrange water reducers and using Whelan, Guar and Xanthan gum technology to try and offset some of theproblems of the continued slow increase in thickening found in cellulose ethers. In general, a combination of both approaches is still in use today.
The common denominators for these technologies are- to various degrees - bleed and segregation problems,and also a need for mechanical effort to move the concrete into place to overcome the high yield values imparted by the anti-settlement agents. Moreover, these technologies may cause problems related to retardation of setting and entrapment of air due to the organic structure and
the primary involvement of the mixing water from the substances.
It is introduced the third generation of rheology control for the production of self-compacting concrete based on Cembinder¨ technology. Laboratory and full-scale tests with Cembinder¨ used in concrete have shown exceptionally positive properties regarding,strength, stability and durability, i.e. addressing the
potential drawbacks from the previous technologies.
The Cembinder¨ SCC range of products is fully compatible with existing admixtures in general and with existing polycarboxylate based high range water reducers in particular.
The active compound in the Cembinder¨ SCC range of products is an inorganic, highly reactive, water based and modified colloidal silica sol - amorphous silicon dioxide.The products are defined as uniform dispersions of
discrete silicon dioxide particles.
Cembinder¨ SCC products are normally added in sequence with high range water reducers and do not require prolonged mixing time. Additions in mixing water are also possible.
70年代第一代高流动性的自密实混凝土引进了以聚羧酸盐类减水剂及纤维素醚来控制混凝土的流变性能。
第二代自密实高性能混凝土的产生则引进了聚羧酸盐类减水剂和可以改善砂浆增稠方面缓慢增加问题的Whelan, Guar（瓜儿胶），Xanthan gum（黄原胶）等纤维素醚类外加剂，至今我们还在混凝土使用以这种两种复合添加的外加剂。
以上两种外加剂的技术在不同程度上还存在泌水和离析的现象，同时也需要在花费一定的功来克服增稠剂（anti-settlement agents）引起的黏灌性。而且这两种技术还存在由于外加剂的有机结构与水搅拌时所带来的缓凝性和引气等问题。
第三代自密实混凝土的流变控制基于一种叫“Cembinder”的技术；实验室和全面的实验测试使用Cembinder的混凝土，其表现出极其突出的强度，稳定性及耐久性等，同时也克服了以上提到的泌水及离析等问题。
这种Cembinder自密实混凝土外加剂与目前使用的其他外加剂相容，当然也包括聚羧酸盐类减水剂；Cembinder中的活性成分是一种无机、高活性、水性的改性硅溶胶，即无定型
二氧化硅。这种产品的二氧化硅颗粒以分散的、均一的形式分散于溶液中。
其添加于混凝土中时可与聚羧酸盐类减水剂依次加入，无需延长搅拌时间，也可采用搅拌时添加。
以上英文是原版，中文是小弟翻译的；
请各位专家，经验人士就产品应用前景给点意见，万分感激，谢谢！

lcl999

Cembinder作为纳米级的溶液，跟水泥混合时可以继续水泥水和物反应，生成强度更高，更致密的水合硅酸钙盐，其防水性能非常突出，可达10负9次方每秒，其在隧道，地铁及水坝等工程有广泛的应用。