## 5 Conclusions  
The study, aimed at improving the corrosion resistance and durability of geopolymer concrete structures of agricultural buildings, reflects qualitatively and quantifies the ability and effectiveness of geopolymer concrete when working in specific conditions of aggressive environments of livestock buildings:  
1. Its suitability and applicability for the indicated conditions have been proved, and its operation under the influence of such an aggressive environment as a mixture of a solution of lactic, acetic, and oxalic acids has been verified. With a duration of exposure to an aggressive environment of 90 days, concrete samples based on HPV had up to 5% less loss of strength and up to 10% less weight loss compared to concrete based on CV.
2. It has been determined that the most reactive alkaline activator for the studied fly ash in the production of concrete based on HPV is the combination of Na\({}_{2}\)SiO\({}_{3}\):NaOH (1:1).
3. The effectiveness of the developed composition and formulation and technological solutions was confirmed, which is quantitatively expressed in the increase in characteristics in terms of \"compressive strength\" and \"tensile strength in bending\" by 81% and 72%, respectively.
4. The most effective concentration of NaOH was determined--14 mol/L.
5. It has been established that an increase in the HT temperature to 75 \({}^{\circ}\)C leads to an increase in the compressive strength for all compositions of concrete based on HPV. The most favorable heat treatment conditions are created at a temperature of 75 \({}^{\circ}\)C.
6. The relations of changes in the strength characteristics of geopolymer binders are revealed, which allow a detailed quantitative and qualitative assessment of the influence of the studied factors on the change in the system \"composition--hardening conditions--properties\" and can be used in the development of production compositions of binders and composites based on them, as well as their regulation, physical, mechanical, and operational characteristics.
7. The possibility of increasing the durability of structures of agricultural buildings and structures through cost-effective building materials made based on production waste and local raw materials has been substantiated and experimentally confirmed.
8. The vector of further development of research in the direction of progress in the theory of geopolymer concrete and reduction of the carbon footprint in the production of cementless building composites of a new type has been determined; the current research and practical agenda for similar research in areas related to sustainable development following the UN goals have been determined as well.  
Conceptualization, L.R.M., S.A.S., E.M.S., A.B.; methodology, S.A.S., E.M.S.; software, S.A.S., E.M.S., A.B.; validation, L.R.M., S.A.S., E.M.S. and A.B.; formal analysis, S.A.S., E.M.S.; investigation, L.R.M., S.A.S., E.M.S., A.B. and B.M.; resources, B.M.; data curation, S.A.S., E.M.S.; writing--original draft preparation, S.A.S., E.M.S. and A.B.; writing--review and editing, S.A.S., E.M.S. and A.B.; visualization, S.A.S., E.M.S., A.B.; supervision, L.R.M., B.M.; project ad ministration, L.R.M., B.M.; funding acquisition, A.B., B.M. All authors have read and agreed to the published version of the manuscript.  
The APC was funded by Don State Technical University.  
Not applicable.  
The study did not report any data.  
The authors would like to acknowledge the administration of Don State Technical University for their resources and financial support.  
The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.