This study evaluates sustainable dune-sand concrete produced using local dune sand, rice husk ash (RHA), and dried oil sludge. The experimental program included a control mixture (C0) and three modified mixtures (M1–M3). RHA was used as a partial replacement for Portland cement at contents of 20, 40, and 60 kg/m³, while dried oil sludge was introduced as a waste-derived additive at 10, 15, and 20 kg/m³, respectively. The total binder content, defined as Portland cement plus RHA, was maintained at 350 kg/m³, while the mixing-water content and water-to-binder ratio were kept constant at 185 kg/m³ and 0.53, respectively. The RHA was heat-treated at 800 °C for 60 min, immediately quenched in water, and subsequently dried at 105 ± 5 °C until a constant mass was achieved. Among the investigated compositions, M2, containing 310 kg/m³ Portland cement, 690 kg/m³ dune sand, 1110 kg/m³ crushed stone, 40 kg/m³ RHA, and 15 kg/m³ dried oil sludge, exhibited the most balanced overall performance. Its compressive strength reached 27.8 MPa at 7 days, 42.5 MPa at 28 days, and 47.7 MPa at 90 days, while its static modulus of elasticity was 32.7 GPa. M2 also showed the lowest water absorption (3.63%), the highest watertightness grade within the investigated series (W10), and the greatest measured freeze–thaw resistance, completing 223 cycles. Optical microscopy and X-ray diffraction observations indicated a visually more continuous matrix and lower relative intensities of several portlandite peaks in the modified concrete. For the replicate-based properties, mixture composition had a statistically significant effect (p < 0.001). Because RHA and dried oil sludge were varied simultaneously, the results represent their combined effect. M2 is therefore identified as the most balanced composition within the present limited test series, rather than as a universal optimum.

В статье рассматриваются вероятности техногенных землетрясений Кумкольских углеводородных месторождений. Техногенные тектонические движения, непосредственно связанные с разработкой месторождений, наблюдаются во многих нефтегазоносных бассейнах. Причинами геодинамических событий являются прогностические факторы. Хотя сейсмические снимки показали, что область асейсмична, количество образующихся активных новых трещин увеличивается с каждым годом, и было высказано предположение, что сейсмические эффекты при бурении пласта также могут привести к серьезным нарушениям. Потому что месторождение Кумколь со всех сторон окружено сейсмоопасными зонами. Пока что регистрация микрозелени также ограничена. Поэтому возникает необходимость организации специальных сетей мониторинга с размещением высокочувствительных станций на нефтегазовых месторождениях с потенциальными землетрясениями

The present study investigates the development of non-autoclaved aerated concrete (NAAC) incorporating rice husk ash (RHA)-derived amorphous silica, polypropylene microfibers, and a polycarboxylate-based superplasticizer to improve mechanical performance and durability while maintaining low density and thermal conductivity. Experimental investigations included density, compressive strength, thermal conductivity, water absorption, X-ray diffraction (XRD), microstructural observations, and TG–DTA analysis. The developed compositions containing 5–7% RHA and 0.10–0.20% polypropylene microfibers achieved compressive strength values of 4.5–4.8 MPa at densities of 520–560 kg/m³, which are comparable to or higher than values commonly reported for non-autoclaved aerated concrete of similar density. Thermal conductivity decreased to 0.12–0.13 W/(m·K), while water absorption was reduced to 15–18%. XRD, microstructural, and TG–DTA analyses suggested enhanced hydration reactions and improved development of the cementitious matrix due to pozzolanic interaction between amorphous silica and calcium hydroxide. The incorporation of polypropylene microfibers was associated with improved structural homogeneity of the developed NAAC compositions, whereas the superplasticizer enhanced mixture homogeneity and pore stability. The results suggest that the combined use of agricultural waste-derived silica and fiber reinforcement provides an effective approach for producing sustainable and energy-efficient NAAC without autoclave curing.

This study evaluates a wet-activated multicomponent organomineral modifier for sustainable concrete. The modifier was produced by co-grinding Portland cement and rice husk ash (RHA) in the presence of Sika^® ViscoCrete^®-20HE and was subsequently combined with polypropylene fibers. Three modified mixtures were tested after 28 days of curing and compared with a control concrete. The modified concretes achieved compressive strengths of 42.2–45.0 MPa, compared with 36.8 MPa for the control. Among the tested formulations, Mix 2, containing 6 wt.% RHA, 4 wt.% polypropylene fibers, and 1.3 wt.% superplasticizer, showed the most favorable overall performance. Its compressive and flexural strengths reached 45.0 and 5.8 MPa, corresponding to observed differences of 22.3% and 26.1%, respectively, relative to the control formulation. Because the complete mixture compositions and w/c ratios differed, these comparisons do not isolate the contribution of any individual constituent. Fracture toughness increased from 1.15 to 2.16 MPa·m^1/2, water absorption decreased from 6.8% to 5.1%, and freeze–thaw resistance increased from 138 to 242 cycles. Qualitative SEM and XRD observations showed morphological and phase-related differences between selected control and modified specimens; however, these observations did not establish the causes of the measured performance differences. In addition, because no compositionally identical non-activated RHA reference or direct reactivity test was included, the independent effect of wet activation on RHA reactivity could not be established. The investigated integrated modifier therefore shows potential for improving concrete performance while enabling the beneficial use of RHA.