At present, the commonly used water reducing agents in China are naphthalene series, melamine series, sulfamate and aliphatic. Although the water reduction rate of naphthalene series and melamine series is higher, the slump loss is larger, which is not conducive to the transportation and construction of commercial concrete. Sulfamate is too sensitive to the dosage and is prone to segregation and bleeding. As the new aliphatic superplasticizer is widely and deeply used, its superior performance and wide adaptability are gradually demonstrated.
Aliphatic water-reducing agents are available in powder and liquid forms. HSB (High Strence Bing), the aliphatic high-efficiency water-reducing agent, is carbonyl pyroaldehyde synthesized by sulfonation of polymers. The hydrophobic main chain is aliphatic hydrocarbons, hereinafter referred to as HSB, which is a water-reducing agent developed by Henan Province. The main raw materials of this product are NaOH, concentrated sulfuric acid, acetone, formaldehyde, etc. It has wide applicability to cement, obvious reinforcement effect on concrete, small slump loss, and no sodium sulfate crystallization phenomenon at low temperatures. It is widely used in the preparation of pumping agents, retarder, early strength, antifreeze, air entrainment and other types of personalized water reduction. agent, it can also be used in combination with naphthalene-based water-reducing agent, amino water-reducing agent, and polycarboxylate water-reducing agent.
1. First make a benchmark concrete without adding any additives, and control the slump at 7 to 9 cm. Record the water consumption (for example: 210kg water)
2. Add admixtures to make one, and control the slump at 7~9 cm. Record the water consumption (for example: 180kg water)
Aliphatic water-reducing agent High-performance water-reducing agent (water reduction rate greater than 25%) Water reduction rate steps:
Same as above, just collapse The drop degree is controlled at 20~22 cm
(210-180)/210=14.3%.
The above are the steps for measuring the water reducing rate of aliphatic water reducing agents. Correctly measuring the water reducing rate is more helpful for our use and can better understand the performance of the product. This is important to us. It is very useful
How to use aliphatic water-reducing agent
1. Generally dissolve the powder into 30-35% liquid for use. Find the optimal dosage through experiments, and the recommended dosage is 1.5-2%;
2. Add aliphatic high-efficiency water-reducing agent (powder) and mixing water to the concrete together, or post-addition can be used When adding aliphatic high-efficiency water-reducing agent (powder), the concrete should be stirred for 30 seconds;
3. Due to the large water-reducing rate of aliphatic high-efficiency water-reducing agent (powder), the surface of the concrete will appear before it initially sets. It is normal to secrete a layer of yellow pulp. The color will disappear after the concrete is pounded and grouted, or the color will disappear naturally after the concrete is strengthened. The color will disappear faster through watering and curing without affecting the internal and surface properties of the concrete.
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