The Impact On Ratio Of Alkali To Silica To Alkali Aggregate Reaction Of Concrete

Alkali Aggregate Reaction(AAR)is an important issue in the durability of concrete,which will last for decades and have a great impact on the dam.What's worse,it may destroy the whole dam.In consideration of the tremendous costs and the undesirable effect of the maintenance,prevention is the best way to reduce the effect of AAR.China has the most dams in the world,over 90 percent of which are made of concrete because concrete is more reliable and durable than other materials.AAR is mainly divided into three categories including Alkali Silica Reaction,Alkali Carbonate Reaction and Alkali Silicate Reaction.The majority of research says that ASR could be avoided by controlling the content of Alkali in the concrete at a certain level.Such point of view is still in controversy.The reason is that the essence of ASR is the reaction between alkali and silica,the study on one aspect must be biased.Some data indicate that the colloform expansibility may vary from one situation to another in the case of the same content of alkali.On concrete structures or components,the final expansion and deformation should depend on the number of active aggregate contained in the concrete and the expensive property of the colloform.The study has been carried out by mainly the experimental approach as well as theoretical analysis.With view to various view points on AAR from many researches and different methods they used,the study evaluated the expansion of the concrete specimens and analyzed the impact of the ratio of alkali and silicon on the concrete alkali-aggregate by using two methods CECS and ASTM C227.The findings of the study will provide experimental data and support for the question of how to control the ratio of alkali and silicon in the concrete.