Technobius

Utilization of water treatment plant sludge in concrete mix

2025-09-02T18:32:13+05:00

This article presents the results of research on the processing of sludge generated at the Main Treatment Facilities (MTF) of Almaty, Kazakhstan, for use in concrete mixes. A nominal concrete mix composition was selected for sample production, consisting of Portland cement, crushed stone, sand, water, Interplast AT superplasticizer, and sludge from the horizontal settling tanks of the MTF. Samples were tested for compressive and flexural strength, water absorption, permeability, and density, revealing that replacing 5% sand with MTF sludge decreases compressive and flexural strengths at 28 days by 13.3% and 3.7%, respectively. In terms of water absorption, the best performance was observed in the sample containing 10% sludge from the MTF replacing part of the sand.

The influence of stabilizers on the strength characteristics of soils in the Western Kazakhstan region

2025-09-24T14:43:16+05:00

The paper presents the results of laboratory studies of soils in four regions of Western Kazakhstan: Atyrau, West Kazakhstan, Aktobe, and Mangystau regions. Laboratory tests determined their physical and mechanical properties, while IR Fourier spectroscopy was applied to analyze mineral composition. Modern stabilizing additives were introduced into the soils, and compressive strength was evaluated after 7 and 28 days. The results demonstrated a 1.5–2.5-fold increase in strength compared to untreated samples, with maximum values ranging from 4 to 6 MPa. The greatest effect was observed in sandy loams and carbonate-rich soils, confirming the high potential of stabilizers for enhancing road base performance in the region.

Application of computational methods for real-time monitoring and structural integrity assessment of reinforced concrete structures

2025-09-16T22:21:02+05:00

This study develops and validates a method for real-time monitoring and structural integrity assessment of reinforced concrete facilities in Karaganda, Kazakhstan, integrating finite element modeling (FEM), machine learning (ML), and digital signal processing (DSP). Three pilot objects were analyzed: a three-span bridge, an 18-storey residential building, and a reinforced concrete highway section. FEM models built in ANSYS 2024 R1 were linked with calibrated sensor networks (strain gauges, accelerometers, thermocouples, tiltmeters, weather stations). Data processing was performed in MATLAB and SciPy, with ridge regression models (R² ≈ 0.85) used for defect prediction. Results showed close correspondence between calculations and measurements: deviations of 2% for the bridge (r = 0.98) and 4% for the building (r = 0.95) met the ≤5% accuracy target. The road section produced a 25% error (r = 0.90), mainly due to frost heave and heterogeneous traffic. Cost–benefit analysis indicated net efficiency within five years, with cumulative savings of 110–120 million KZT versus 67 million KZT in costs. The findings confirm the effectiveness of integrated digital monitoring for preventive maintenance, though further validation in different climates and materials is required.

The influence of opoka mineral additive on the physico-mechanical properties of gas-ceramics based on low-plasticity clay

2025-09-29T20:37:26+05:00

The article presents the results of scientific and experimental research on the development of highly porous gas-ceramics based on low-plasticity clay from the Rubezhinsk deposit. As a mineral additive, highly dispersed microporous siliceous rock-opoka from the Taskala deposit was used. Opoka is a lightweight, hard, microporous rock characterized by high natural porosity (55-60%) and a density of 1.3-1.5 g/cm³. Hydrogen peroxide, chemically composed of H₂O₂ (perhydrol), was employed as the foaming agent. The raw clay material contains 68% SiO₂, 11.8% Al₂O₃, 3.6% Fe₂O₃, and 5.6% CaO, and is classified as low-plasticity with a plasticity index of 6.5%. X-ray diffraction analysis revealed that the clay is predominantly composed of quartz, feldspar, calcite, and hematite, while the opoka consists primarily of amorphous silica. Experimental studies demonstrated that introducing 10-30% finely ground opoka into the clay slip reduces sedimentation of molded samples during drying from 12% (without additive) to 4% (at 30% opoka), thereby decreasing shrinkage and accelerating structural strength development by 10-15%. The resulting gas-ceramic samples exhibited average densities ranging from 565 to 785 kg/m³, compressive strength between 2.5 and 3.8 MPa, total porosity from 68.4% to 75.2%, and thermal conductivity values of 0.18–0.24 W/m·°C. These results indicate that the use of siliceous opoka significantly improves the performance characteristics of porous ceramics. Thus, the developed gas-ceramic materials combine low density, enhanced strength, and low thermal conductivity, making them suitable for use as effective structural-thermal insulation components in building envelope systems, particularly for the northern regions of Kazakhstan.

Eco-efficient composite cements and arbolite using burnt clay shale from the Mynaral deposit

2025-09-29T20:39:50+05:00

This study investigates the potential of burnt clay shale (BCS) from the Mynaral deposit (Zhambyl region, Kazakhstan) as an active mineral additive in composite cements and arbolite. Thermal and X-ray diffraction analyses revealed progressive dehydration, decarbonation, and decomposition of kaolinite, chlorite, and calcite, with optimal activation at 900 °C. Pozzolanic activity tests confirmed maximum reactivity at this temperature. Mechanical testing showed that 10–15% BCS increased cement strength up to 51 MPa, while higher dosages reduced performance. Arbolite samples with ash-and-slag binders and controlled alkaline additives demonstrated superior density and strength, supported by SEM evidence of dense crystalline microstructures and strong binder–filler adhesion. The findings highlight BCS as an effective, eco-friendly component reducing clinker consumption and CO₂ emissions.

Refined methodology for the analysis of beams on elastic foundations

2025-10-01T14:55:30+05:00

The study proposes a refined method for analyzing beams on a two-parameter elastic foundation, overcoming the limitations of the classical Winkler model. Unlike the traditional approach, which considers soil deformation only in the applied load zone, the proposed methods introduce an additional parameter of bending stiffness, providing a more accurate description of beam-foundation interaction. A governing differential equation was derived, and its analytical solutions are presented for various boundary conditions and loading types. The numerical analysis results show that the distribution of vertical displacement, bending moment, and shear force along the normalized length of the beam is symmetric with respect to the midspan. It has been established that the maximum values of vertical displacement and bending moment are observed at the midspan: the vertical displacement reaches 0.000999157, while the bending moment attains 0.124892. At the same time, the shear force reaches its maximum value near the beam supports, amounting to 0.49966. The results indicate that the stress-strain state critical points of the beam on an elastic foundation are concentrated at the midspan (for displacement and bending moment) and at the supports (for shear force). The analysis demonstrates that the maximum shear stresses occur near the fixed end of the beam (x = 0, z = 0), gradually decrease to zero at midspan, and reach negative values at the opposite end (x = 1, z = 0). The normal stresses vary linearly along the cross-sectional height, from negative in the lower zone (x=1/2, z = −1/2) to positive in the upper zone (x=1/2, z = 1/2), with values close to zero near the neutral axis (x=1//2, z = 0). Comparison with the classical Winkler model shows close agreement in displacements, bending moments, and shear forces, while the proposed method provides improved accuracy in predicting normal and shear stress distributions.