RECYCLING AND EFFICIENT USE OF THERMAL POWER PLANT FLY ASH AS PART OF DRY BUILDING MIXES

In this paper, the possibility of using fly ash from thermal power plants (TPPs) as a component of dry building mixtures (SCS) for masonry mortars is investigated. Its effect on the strength and rheological characteristics of mortars, as well as the economic and environmental feasibility of the application, are analyzed. Determination of the efficiency of the use of ash entrainment of thermal power plants in the composition of dry building mixtures, development of optimal formulations and assessment of their impact on the technological, mechanical and operational properties of building materials Cement, quartz sand, thermal power plant fly ash, lime-carbonate dust (IKP) and Polyplast SP-3 superplasticizer are used as the main materials. The experimental study was carried out using mathematical planning, including varying the parameters of the composition of mortars, such as cement consumption, volume concentration of ash-lime part, water- cement ratio and superplasticizer content. The indicators of mobility (blurring of the solution cone) and strength of solutions at the age of 28 days were studied. The study showed that the introduction of fly ash into the composition of cement and cement-lime mortars helps to reduce cement consumption by 30-50 kg/m³ while maintaining or increasing their strength characteristics. The optimal content of fly ash is 40-60% of the total amount of binder, which ensures good mobility and minimal stratification of solutions. The combined use of fly ash and superplasticizer improves workability without significantly increasing the water-cement ratio. The use of TPP fly ash as a component of dry building mixtures makes it possible to effectively replace part of cement and lime, reduce the cost of mortars and reduce the negative impact on the environment. Optimal compositions of solutions with fly ash provide high performance characteristics that meet construction requirements