vvvConcrete Expanding Agentvvv

I、Profile

　　Concrete constructional work is apt to crack for the constringency of Reinforced concrete. This will arouse leakage, corrosion and the reduction of its service life. The expanding agent produced by the company is the fouth generation products of the company. The products are mainly used in the self water proof of concrete structure. Adding 6～8％ CEA、BY to replace the same weight concrete, crack of concrete work can be avoided and leakproof performance will be improved. Also, this can abolish external waterproof and save flexible waterproof; extend the clearance of control joint, simplize contructional process, decrease engineering cost and achieve permanent waterproof.
　　CEA、BY Concrete Expanding Agent takes calcium sulphoaluminate as the main content. It features the stable materialization and low basic content. It is a safe and permanent concrete external reactant for crack resistance and waterproof. It can be used together with pumping agent, retarder, water reducing agent and antifreeze to meet the needs of different engineerings.

II、Technical Performance of CEA、BY Concrete Expansive Agent

（1）Performance of materialization of CEA、BY
　　1、Colour：Offwhite
　　2、l：2 datum cement mortar made of CEA、BY，keeping it in water for 7 days，limiting expansive rate is more than 0．025％.
　　3、6～8％ CEA、BY（8％ adulterated volume suggested） to replace the same weiht concrete, stress up to 0．2-0.8MPa：leakproof performance up to P₂₅： antifreeze performance up to F₂₅₀.
　　4、Chemical composition of CEA、BY
　　Alkali content R₂0＝Na₂O+0.658K₂O=0.21

　　5、Reinforcing Steel Rust Experiment
　　Launch ￠16×50mm plain reinforcing bar into CEA、BY concrete，keeping for 28天、2 months、3 months、6 months，no rust in observation
（2）、Application
　　1、Adapt to compensation constriction reinforced concrete structural project and job placed construction, such as parking lot, air port runway and highway.
　　2、Leakproof concrete engineering, such as the waterproofing work of swimming pool, waterproof roofboard and underground structure.
　　3、Rear pouring slot of pourinplace concrete engineering, concrete pouring slot of large struction, concrete rear pouring slot of dyke and sluice valve.
　　4、Lining.
　　5、Back grouting materials of machine base and foot screw.
（3）、Notice
　　1、Adapt to six kind of cements with the strength grade more than 32.5 and the unilateral dosage should be no more than 350kg/m³.
　　2、Accurate measurement of all kinds of materials, admixtion time should be longer than the common concrete by 30～60s.
　　3、Concussively compact the concrete and begin maintenance after 12H from casting. Maintenance period should be larger than 14 days.

III、Package and Storage

　　The company provides the products both in bags and in bulk (50_-1Mg each bag). As well, it also produces various of other specifications of products at customers's request. CEA and BY concrete expansive agent should be kept in dry places for no more than half a year.

IV、Using Effect

　　In the engineering of Jiuxianqiao sewage treatment in Beijing 9-5 Key Projects, over 3000 tons of expansive agent produced by the company were used. At present, oxidation ditch, depositing tank and concentration tank have all been used with a perfect leakproofing effect.