▓ The design of the mix ratio of the compensating and shrinking concrete is basically the same as that of ordinary concrete, and the water-binder ratio is adjusted according to the slump requirements of the concrete, which should generally not be greater than 0.5.
▓ The amount of CSA expansion agent added is calculated according to the following formula, that is: blending amount = Z / (C + Z + F), where: C—cement, Z—high-performance CSA expansion agent, F—fly ash and other active mixed materials.
▓ CSA expansion agent can be directly mixed with concrete, cement, sand, stone, etc. The amount of different (internal mixing, equivalent replacement of gelling materials) for different uses is as follows:
Waterproof mortar: The dosage is about 6-10%.
Reinforced concrete: 6-10%, the amount of each engineering part should be determined according to tests.
Filling concrete: 10-12%, such as concrete-filled steel tubes, cast-in-place piles, etc.
▓The strength grade of concrete mixed with CSA expansion agent is generally not lower than C25, the amount of cementitious material in each concrete is ≧ 300kg, the cement grade is ≧ 32.5 #, and the mortar strength is not lower than 10MPa.
▓ Concrete mixing time should be 10 to 30 seconds longer than usual. The accurate measurement of the expansion agent, the measurement error of the ingredients is ≤ ± 1%.
▓ Concrete transportation and vibration are the same as ordinary concrete. After the pouring, it should be cured in a timely manner for a period of not less than 14 days. Keep it moist during the curing period. In particular, early curing must be strengthened to prevent early dehydration of the concrete.
▓The space between expansion joints of reinforced concrete structures mixed with high-performance CSA expansion agent can be extended to more than 60M. The seamless design construction technology can be used to eliminate the post-casting belt (except for the post-settling belt after settlement).
▓ The CSA expansion agent can be used in combination with other admixtures to make it have the functions of pumping, early strength, retardation and anti-freezing, but it must undergo adaptation tests.