Analysis Of Dry Mortar With Recycled Fine Powder Performance Evaluation

Cement as a kind of significant water hydraulic cementing materials, social market demand greatly, but the production energy consumption and pollution of cement is huge. So how to reduce the amount of using mortar and concrete has become the development direction for environmentally material,.In this paper, the waste residue which is produced by the concrete enterprise is crushed and milled to produce a potentially active recycled fine powder. According to the requirement of the national standard for the chemical index of active mixed material, we tested the recycled fine powder's chemical component. The results show that the recycled fine powder's loss on ignition, containing water, sulfur trioxide content and other chemical indicators are meeting the pozzolanic materials and fly ash requirement of national standard. The physical performance index show that 45?m sieving residue and the sand flow rate was slightly higher than the natural volcanic gray matter flow rate, but it was lower than the grade III fly ash index. Its 28 d compressive strength ratio is lower than the national standard requirements of the above two kinds of materials. Therefore, in order to improve the activity of recycled fine powder, using sodium hydroxide, sodium sulfate, sodium chloride and triethanolamine four chemical activator for recycled fine powder activity provocation test, in the interest of characterize the activator activity excitation effect, this paper presents activation index definition and calculation formula.Based the dry-mixed mortar proportion(reference sample) without recycled fine powder, the recycled fine powder to substitute the influence on the performance of mortar dry-mixed mortar(masonry mortar DM-M5 and plastering mortar DP-M5) part of the cement. The results show that the best replace rate for the recycled fine powder were 20% and 25%. With the replacement rate of recycled fine powder increased, the compressive strength of dry mixed mortar decreased obviously. Adding activator of recycled fine powder dry-mixed mortar is better than not adding activator of recycled fine powder dry-mixed mortar(blank). Especially dry-mixed masonry mortar compressive strength and dry-mixed plastering mortar bond strength is obviously improved, so it establish a relationship between the activity of activator excitation index and dry-mixed mortar compressive strength.According to the test results of the physical and chemical properties for fine powder and the test results of performance for recycled fine powder on dry mixed mortar, the evaluation system of the basic parameters and the evaluation system of the application parameters are discussed. It provides technical reference for using recycled fine powder to product dry-mixed masonry mortar(DM-M5)and plastering mortar regeneration(DP-M5).Using recycled fine powder to replace part of cement mortar can save the amount of dry-mixed mortar and reduce the cost of dry-mixed mortar. In other word, this method can also ease the energy consumption and environmental pollution caused by cement. Due to the reuse of waste concrete, this method is an important measure for the sustainable development of building mortar and concrete industry, which has good environmental effect, economic effect and social effect. At present, there is a lack of research on the performance index system of recycled fine powder in China, In this paper, the research on the performance analysis of recycled fine powder is of great reference value to the production of dry-mixed mortar by using recycled fine powder.