2. 1. 1 cement: 325 ~ 425 ordinary portland cement or slag portland cement is used. When slag portland cement is used, early strength measures should be taken according to specific conditions to ensure the strength of wall formwork removal and gusset plate.

2. 1.2 sand: coarse sand or medium sand. When the concrete is lower than C30, the silt content is not more than 5%. When the concrete is equal to or higher than C30, the silt content is not more than 3%.

2. 1.3 pebble: pebble or gravel with a particle size of 0.5 ~ 3.2 cm. When the concrete is lower than C30, the silt content is not more than 2%, and when the concrete is equal to or higher than C30, the silt content is not more than 65438 0%.

2. 1.4 water: clean water without impurities.

2. 1.5 admixture: it shall meet the technical requirements of corresponding standards, and its dosage shall be determined by the laboratory according to the construction requirements.

2. 1.6 main machines and tools: concrete mixer, bucket, trolley, scale, plug-in vibrating rod (high frequency), shovel, iron plate, wood trowel, flat shovel, water spoon, bucket, hose, etc.

2.2 Operating conditions:

2.2. 1 After completing the concealed inspection procedure of steel bars, pay attention to check the supporting iron and cushion blocks to ensure the thickness of the protective layer. Verify the position, quantity and fixation of embedded parts, reserved holes, water and electricity embedded pipelines and boxes (slots) in the wall.

2.2.2 Check whether the lower mouth, hole and corner template of the template are spliced tightly, whether the corner column reinforcement is reliable, and whether all kinds of connectors are firm.

2.2.3 Check and clean up the residual sundries in the template, and rinse them with water. Brick walls and wooden patterns of external brick internal mold should be watered and wetted at room temperature.

2.2.4 Concrete mixers, vibrators and scales have been inspected and maintained. Measuring instruments have been checked regularly.

2.2.5 Check the power supply and wiring, and prepare for lighting at night.

2.2.6 Trial matching shall be carried out by the laboratory to determine the concrete mixture ratio and admixture content, pay attention to saving cement, facilitate construction, meet the early strength requirements of concrete, and the wall surface shall be smooth after formwork removal to meet the requirement of no plastering.