In order to ensure the quality of the concrete project, meet the concrete pouring intensity of the construction plan, ensure the production order of the second phase of the project, reduce environmental pollution, and realize civilized construction.
Two large-scale automated concrete centralized mixing plants with a total production capacity of 120m3/h and capable of producing two concrete varieties are set up in the construction of this project to meet the concrete supply of the entire project.
1. Selection of site for centralized concrete mixing plant
Since this project is a second-phase expansion project, in order to ensure the normal production of the original first-phase project and avoid interference with other construction activities, the following conditions should be considered for the site selection:
- The safe distance between the mixing station and the blasting operation point is not less than 300 meters.
- The site of the plant should be convenient for the mixing station to accept various materials and transport out the concrete. In order to reduce concrete separation and slump loss and temperature changes during transportation, the mixing station should be as close to the construction site as possible, and the transportation distance should not exceed 20 minutes according to the time between concrete leaving the machine and entering the warehouse.
- The plant area should be convenient for water supply, drainage and power supply.
2. Selection of equipment for mixing
According to the requirements of the construction schedule, the hourly production capacity of the concrete mixing station is 120m3/h, and it has the ability to produce two varieties of concrete at the same time. Based on this, we choose four 1m3 concrete mixers and use two mixers to form a production line. The production lines constitute a centralized concrete mixing station.
3. Cement storage and transportation facilities
This mixing station uses bulk cement, and has 4 100T bulk cement storage tanks. The transportation of cement mainly considers the supply and transportation of cement manufacturers, and also prepares two 30-ton bulk cement tankers as emergency auxiliary transportation.
4. Storage and transportation facilities for sand, stone, and admixtures.
The centralized mixing station is equipped with a 2000m2 sand and stone stacking yard. Equipped with two ZL50 loaders for stacking and loading into the aggregate bin of the mixer. Establish an exclusive material library for materials such as additives for storage and management.
5. Concrete transportation
The mixing station is about 500 meters away from the construction pouring site, and the concrete mixer truck is used to transport the concrete to the concrete transportation pump bin at the pouring site. Pumped by concrete pump to each pouring point. This site is equipped with two
HBT80 concrete conveying pump and 5 8m3 concrete mixing and conveying trucks are used as the main conveying equipment of concrete, which can ensure the conveying of engineering concrete.
6. Measures to ensure the uninterrupted production of the centralized mixing plant.
This station is equipped with a 315kw diesel generator set as the self-provided power source of the mixing station.
7. Concrete Quality Assurance Measures
- The centralized concrete mixing station shall establish a quality assurance system and organization for the construction of the centralized concrete mixing station in accordance with the ISO9002 standard and the company's quality system requirements. And formulate corresponding quality management rules and regulations.
- The quality control of concrete raw materials. The quality control of concrete raw materials is the key to ensuring the quality of concrete. The raw materials of concrete must be checked by the professional personnel of material experiment and the station master. Unqualified large materials must be withdrawn from the site.
- Concrete production process and quality control of finished products
The mixing station carries out electronic automatic measurement and batching of concrete sand, stone, cement, fly ash, water and additives, and the error is within the national standard. All types of work in the mixing station are certified.
- Control of the accuracy of the electronic batching scale of the concrete mixing station
After the concrete mixing station is installed, the accuracy of the batching scale is inspected and identified. The accuracy of the aggregate electronic batching scale is ≦±2%.