Application and development of wet-mixed gypsum mortar

Affected by the new economic normal, the concrete industry has begun to face new opportunities and challenges. The development of the industry no longer relies solely on the rapid economic growth and infrastructure investment, but has begun to seek technological and management innovation and development. The transformation of the model realizes the healthy development of the industry. In particular, the concrete industry is facing increasing pressure on environmental protection, and there is an urgent need to find breakthroughs for industry transformation and upgrading. The “Thirteenth Five-Year Plan” reform clearly put forward the idea of ​​”releasing new demands, creating new supplies, promoting the vigorous development of new technologies, new industries, and new business formats, and accelerating the transformation of development drivers.” Central leaders have repeatedly put forward the idea of ​​”supply The concept of “side reform” means starting from the supply and production side to promote economic development by liberating productivity and improving competitiveness. The production and promotion of wet-mixed gypsum mortar by commercial concrete enterprises is in line with the essence of “supply-side reform”.

1. Product analysis

Building gypsum mortar can be divided into ready-mixed gypsum mortar and ready-mixed gypsum mortar according to its mixing conditions. Among them, ready-mixed gypsum mortar is not allowed to be used for work due to “prohibition”. The promotion has been gradually eliminated, similar to the previous self-mixing concrete. At present, the mainstream use of construction gypsum mortar is ready-mixed gypsum mortar. According to different production conditions, ready-mixed gypsum mortar can be divided into two categories: dry-mixed gypsum mortar and wet-mixed gypsum mortar.

1.1 Dry mixed gypsum mortar

It is a kind of dry mixed gypsum mortar that is mixed with inorganic cementitious materials and various organic polymer additives in a certain proportion after drying and screening. The granular or powdery mixture is transported to the construction site in bags or bulk, and can be used directly after adding water and mixing.

Advantages: Ready to mix, easy to construct. Disadvantages: higher production costs: “segregation” of materials can easily cause quality problems: secondary stirring can easily produce dust pollution.

1.2 Wet-mixed gypsum mortar

Cement, fine aggregate, admixtures and water, as well as various components determined based on performance, are measured and mixed in a mixing station in a certain proportion. After preparation, the wet mix should be transported to the construction site by a mixer truck and used within the specified time. The traditional wet-mixed gypsum mortar continues the concrete mix proportion design idea and uses concrete admixtures, which often cannot meet the construction requirements. The new wet-mixed gypsum mortar is based on the tradition and mixed with some high-tech admixtures, and introduces a new concept of centralized production and distribution of wet-mixed gypsum mortar mixing stations and ready-to-use on-site quality requirements. The time can be adjusted in time according to construction needs to adapt to the construction requirements of different working conditions.

Advantages: low production cost, controllable quality, green and environmentally friendly. Disadvantages: The construction unit needs to reasonably arrange personnel and materials according to the actual situation, which may easily cause material waste in the early stage.

2 Development prospects of wet-mixed gypsum mortar

2.1 Cost advantage

Commercial concrete companies have the advantage of large-scale centralized procurement of raw materials, and the transformation of wet-mixed gypsum mortar production lines The cost is basically negligible, and existing concrete mixer trucks can also be used for material distribution. There is no need to consider additional investment in new equipment, and the original fixed costs can be amortized. According to enterprise research and construction site inspections, compared with dry-mixed gypsum mortar, commercial concrete companies simply process raw materials during production. When producing the same amount of construction gypsum mortar, wet-mixed gypsum mortar saves 5% to 10% of the cost, which means Wet-mixed gypsum mortar has a great competitive advantage in the market. </p