ArticleManagerReady-mixed mortar refers to the commercial mortar produced by batching and mixing in specialized factories. Replacing traditional mortar with ready-mixed mortar, on the surface, is only a transformation of production mode, in essence, it is a major breakthrough in mortar design, production, quality, logistics system, construction technology and application scope, is one of the important symbols of construction modernization and national civilization, is an important means to promote green buildings, develop green building materials, from concept to technology is a new revolution.
Banning on-site mixing of mortar, realizing the commercialization of mortar and mechanization of construction, is the result of promoting the development of circular economy, implementing energy conservation and emission reduction, and realizing technological progress in the construction industry. So, ready-mixed mortar VS ready-mixed mortar, where is the excellence?
01. Physical properties
Ready-mixed mortar is produced by professional manufacturers in accordance with the scientific and reasonable ratio of raw materials, using automated production lines, transported to the place of use through special transport vehicles, and stored in special tanks for engineering materials.
Since the natural sand needs to be screened and dried in the production process, the impurities such as gravel and mud contained in the natural sand are basically removed, which can fully ensure the accuracy of the mixing ratio of mortar raw materials. In addition, in the production process of ready-mixed mortar, the fiber, coagulant, dispersible polymer powder, early strength agent and other modified additives added separately according to the needs of the project greatly improve the physical and mechanical properties of ready-mixed mortar.
On-site mixing mortar is the operator with manual screening, with shovel or trolley measurement, small mixer mixing. Impurities such as gravel and mud in the sand cannot be effectively removed; The measurement of sand, cement and water cannot be accurately controlled, resulting in the arbitrariness of the ratio of raw materials; The mixing is uneven, and finally the quality of the mortar is too discrete, resulting in the occurrence of construction quality problems.
02. Construction ergonomics
Ready-mixed mortar (wet mix, dry mix) can greatly reduce the labor intensity of the construction site, speed up the construction speed, and improve the operation efficiency. Especially the use of mechanical spraying in painting construction further reflects the advantages of using ready-mixed mortar.
With ready-mixed mortar mechanized construction, 3 plasterers, 1 auxiliary worker, two mechanical operation work as the operation team, 6 operators can paint the construction 720㎡~900㎡ every day, the labor salary is about 1100 yuan ~ 1400 yuan, that is, the labor cost per square meter wall is about 1.22 yuan ~ 1.94 yuan / ㎡.
According to the total mechanical cost, electricity and water cost of mechanical spraying and painting construction is about 1.5 yuan / ㎡, and the material cost is about 10.5 yuan ~ 14.5 yuan / ㎡, the construction cost of ready-mixed mortar is 13.22 yuan ~ 17.94 yuan / ㎡. If the influence of factors such as the acceptance force of manual operation is considered, the advantages of mechanical construction with ready-mixed mortar are more obvious.
On-site mixing mortar for wall painting construction, mortar mixers, ash transporters, plasterers and other workers on average about 30 square meters of wall painting per person. According to the calculation of two plasterers and one auxiliary worker, the daily painting construction area of three operators is about 90 square meters, and the labor salary is about 500 yuan ~ 650 yuan, that is, the labor cost per square meter of wall is about 5.5 yuan ~ 7.5 yuan. According to the total mechanical cost, electricity and water cost of on-site mixing mortar is about 1 yuan / ㎡, and the material cost is about 8 yuan ~ 11 yuan / ㎡, the construction cost of on-site mixing mortar is about 14.5 yuan ~ 19.5 yuan / ㎡.
03. Raw material consumption
Compared with on-site mixing mortar, ready-mixed mortar can save about 40kg of cement, about 50kg of sand and about 30kg of lime per ton of mortar. In addition, ready-mixed mortar can also be made of artificial sand from solid wastes such as tailings, steel slag and slag for production, and can also be mixed with some fly ash, slag powder, etc. instead of cement for production, which has found a way out for the comprehensive utilization of industrial solid waste.
Construction site mixing mortar, because the measurement of sand and bulk cement can not be effectively controlled, it is impossible to control the mortar mixing ratio, and material waste is more common. Coupled with the serious shortage of the actual number of yellow sand entering the site, it often causes the construction unit to exceed the budget for both yellow sand and cement.
04. Environmental protection
Ready-mixed mortar is produced by professional production enterprises, under the conditions of close to closed production process, transported to the site by special transport vehicles, stored in a special dry-mix mortar storage barrel, ready for use by the construction unit. The whole process not only reduces the consumption of raw materials and waste, but also has no noise of the mixer at the construction site, will not be blocked by rainwater flushing into the sewers, and has no pollution to the environment.
On-site mixing mortar not only requires a dumping site for yellow sand materials, but also cannot utilize industrial solid waste. The cement, yellow sand and other powdery materials on site will also produce dust pollution such as “throwing, sprinkling, rising, dripping, leakage” during transportation and construction sites, and powdery materials such as yellow sand stacked in the open air will also produce secondary dust pollution. In the rainy season, cement, yellow sand and other materials may become mud and sand, flowing into urban pipelines and causing blockages, affecting the living environment and urban environmental remediation.
05. Quality control
All the ingredients of ready-mixed mortar are in the production workshop, in strict accordance with the requirements of mortar mixing ratio, the raw materials are fully mixed and evenly mixed and transported to the construction site for storage. Since ready-mixed dry-mix mortar needs to be screened and dried during processing, the sand in the mortar almost does not contain impurities such as mud, which is more in line with the standard requirements and can ensure the accuracy of measurement. Coupled with the correct measurement of cement and the appropriate amount of modifier, the product quality of mortar has been greatly improved.
On-site mixing mortar is affected by the site environment, it is impossible to remove impurities in the sand, the water content and sludge content of yellow sand cannot be effectively controlled, the measurement of cement, yellow sand, water and other materials can not ensure the correctness, it is impossible to talk about the control of mortar matching ratio, let alone control the quality of mortar.
Replacing the traditional on-site mixing mortar with ready-mixed mortar is one of the important ways to improve civilized construction, reduce dust and dust, improve project quality, and speed up construction. The promotion of ready-mixed mortar that meets environmental protection requirements at construction sites has become an urgent task for local construction authorities. At present, most regions in China have introduced corresponding local standards and policies and regulations to actively promote ready-mixed mortar. With the clarity of policies, the market is gradually ripe, and an attractive vast industrial blue ocean has begun to appear.