Everyone know the quantities of concrete engineering is very big, but with the continuous development of era, the durability of poly carboxylic acid water reducing agent are also put forward higher and higher requirements, therefore, to improve the durability of sustainable development strategy for the current implementation, better use of resources, save energy and protect the environment, all has the very vital significance.So what are the factors that affect the durability of polycarboxylic acid water reducer?
1. Chloride ion is also an important factor affecting the durability of concrete.Chloride ion damage to the steel surface passivation membrane has a special role, when the content of chloride in concrete exceeds standard, steel bar corrosion, and the presence of water and oxygen is the necessary condition of steel bar corrosion as a result, if the concrete cracking, caused by the passage of water and oxygen, steel corrosion is accelerated, and further, forming the cracks of concrete spalling of concrete cover, the final cost component bearing capacity.
2. Alkali is one of the main factors inducing concrete alkali-aggregate reaction and an important factor affecting concrete durability.However, dam damage caused by alkali-aggregate reaction is common at home and abroad. The alkali in concrete mainly comes from cement, fly ash, water reducer and other raw materials.The world also attaches great importance to the control of alkali content. South Africa stipulates that the total amount of concrete alkali shall not exceed 2.1 Kg/m3, the United States stipulates that the total amount of concrete alkali shall not exceed 3.3 Kg/m3, and China stipulates that the total amount of concrete alkali shall not exceed 2.5 Kg/m3 in the three gorges project.As one of the five components of concrete, the alkali content, especially the Na2SO4 content, directly affects the total alkali content of concrete.
