We often need to pour lightweight concrete in the fourth floor to the second floor of the main building underground garage and the room, the second floor platform floor, etc. to meet the design function and thermal insulation requirements, and have a certain strength.
It is easy to produce segregation and stratification in the construction of lightweight concrete. Due to the characteristics of porous material, rough surface, high water absorption and low compressive strength, it is different from ordinary concrete in material storage, preparation process, on-site pouring and maintenance.
1. Mix proportion design
In order to meet the technical requirement of 10Mpa, which is controlled by wet density and compressive strength, a laboratory test was carried out to determine the mix ratio of normal temperature and winter construction. According to the result of trial matching, the mixture ratio of normal temperature and winter application is made up of polystyrene foam particles and clay ceramsite. The raw materials of light concrete per cubic meter are: 525 ordinary Portland cement 601Kg, additives (special additives for light concrete, mainly consisting of naphthalene sulfonate polymer), 2.4Kg, 541Kg ceramsite (light and heavy ceramsite mixtures can be selected to meet density requirements), 10Kg polyphenyl foam particles, 203Kg water; winter mixing ratio and raw materials are basically the same, only slightly adjusted, mainly. It is to change the additive into antifreeze agent with dosage of 5.4Kg. The compressive strength of the specimens with the above two mixtures is greater than or equal to 10Mpa after standard maintenance for 7 days, and the compressive strength of 28GD is greater than 10Mpa.
2. Manufacturing Technology
Lightweight concrete is not suitable for long-distance transportation, and because of the small amount of pouring and scattered, it adopts on-site self-mixing mode. TDCM500-DHT Tilting Drum Concrete Mixeris installed on site.
