一、Product properties

1. Low alkali content. Because raw materials with high alkali content are eliminated, the total alkali content is reduced to 0.5%;

2. Small dry shrinkage: dry shrinkage rate over 21 days is ≥-0.010%;

3.Concrete mix with expansion agent has no corrosion to steel bars, and has no pollution to water;

4.The product has good corrosion resistance to sulfate.

二、Precautions of UEA high-performance concrete expansion agent

1.The mixing ratio is as same as ordinary cement. When preparing expansive concrete, according to specifications, the amount of cement shall not less than 300kg/m3. The mixing amount of UEA high-performance concrete expansion agent is calculated as k = (UEA expansion agent / cement + admixture + UEA expansion agent) * 100%. The optimal mixing amount of UEA expansion agent is depended on the project requirements and concrete types. The mark is determined by the test result;

2.The mixing ratio of UEA high-performance concrete expansion agent is determined through experiments. The concrete mixed with expansion agent shall be tested for items such as slump, strength and impermeability of concrete, as well as limited expansion rate. According to GBJ50119-2003, the compensation shrinkage concrete index mixed with expansion agent is: the limited expansion rate of water curing for 7 days is ≥0.025%. The concrete must reach designed index. The user shall add different amount of expansion agent based on various structural parts for meeting the requirements of compensation shrinkage;

3.Concrete deformation (expansion and shrink) and limitation form a contradictory unity. Expansion must be prestressed in the structure through reinforcement and vicinal constraints. Therefore, the fine and dense reinforcement are primarily used in the design. Individual openings and wall column joints are easy to crack because of stress concentration; thereby additional reinforcement shall be added. Because the walls are difficult to construct, maintenance is difficult to carry out, easily to be affected to the external temperature difference, it is prone to longitudinal cracks. The spacing of horizontal structural bars of walls is required to be less than 150m; the reinforcement ratio is at 0.5%. Within 1m in the middle of the wall. Increase the density of the horizontal bars to 80-100 mm to form a “hidden beam” which is used to balance the contraction stress. The horizontal bars are placed on the outside of the stressed bars to ensure the thickness of the concrete protection layer;

4.The post-cast joint spacing of concrete mixed with expansion agent shall be extended to 60m. The super-long structure exceeds 60m can use an expansion reinforcement belt of 2m width to replace the post-cast joint. It uses continuous or intermittent seamless design and construction method, which are the patents of China Building Materials Academy. Technical consulting services can be sought from China Building Materials Academy to ensure the quality of the project.   

三、Applications of UEA high-performance concrete expansion agent

1.It is suitable for preparing structural self-waterproof concrete and compensating for contraction concrete;

2.It is suitable for preparing high-efficient composite anti-cracking waterproofing agent;

3.It is suitable for preparing high strength, high performance concrete;

4.It is suitable for preparing high strength non-shrink grouting materials.