The purpose of this work was to investigate the effect of the burning environment on the properties and phase composition of clinker-based ceramic specimens made from loam with diatomite and bentonite clay in order to develop technological parameters for the manufacture of clinker products. The main raw material used for the experiments was local fusible loam from the Almaty deposit, which is the basis for the production of 75 and 100 grade ceramic bricks. Diatomite from Utesai deposit (Aktobe region) and highly plastic bentonite clay from Darbazin deposit (Turkestan region) were used as additives. Loam and bentonite clay were applied after grinding and sieving through a 1 mm sieve. Diatomite was applied after grinding and milling until it had completely passed through a 0.315 mm sieve. The raw materials are mixed after dosing, and then water is added in the amount required until a pliable mass is obtained. To investigate the properties of the products, standard cylinder samples were prepared with a diameter of 50 mm and a height of 50 mm. The cylinder samples were pressed on a hydraulic press at a pressure of 2–4 kN. The samples were dried in a desiccator at 95–100 °C for 2 h. After drying, the products were burning in a muffle kiln. The analysis of the properties of the burned products showed that the optimum ratio in the ceramic mixture of loam and diatomite to loam and bentonite clay is 85%:15%. After burning in a slightly oxidising environment at 1170 °C, the ceramic specimens correspond to Class 2 for the medium-density and compressive strength grades M 400 and M 500 (GOST 530-2012 (Government standard). X-ray diffractometric analysis showed that the products contain augite, quartz and anorthite as crystalline phases, with the former predominating. After burning in a reducing atmosphere, at 1170 °C, the properties of the samples have higher values compared to the samples burning in a weakly oxidising atmosphere. The resulting properties, according to the regulations, are characteristic of clinker bricks (DIN V 105-1 (technical requirements for clinker façade bricks). After burning in a reducing environment, the phase composition of the products changes qualitatively; in addition to augite and quartz, albite, diopside, orthoclase and haematite are present in the samples.

In the context of intensified construction and stricter requirements for the energy efficiency of buildings, the use of thermal insulation materials and technologies is becoming particularly important. One promising area in this field is the use of thermal insulation mixtures, which are versatile, adaptable, and highly reliable in operation. Mixtures based on fillers with a porous structure and materials that impart thermal insulation properties, which provide higher thermal insulation properties, are of great interest. However, the development of dry thermal insulation mixtures is hampered by insufficient study of their physical, mechanical, and operational characteristics. This article presents the results of research work on the development and study of dry building thermal insulation mixtures. A distinctive feature of the work is the creation of a composition of dry building thermal insulation mixtures based on local raw materials, such as diatomite, its thermal modification at a temperature of 900 °C, the use of expanded perlite sand, lime, and Portland cement. Research into the properties of modified diatomite has shown that its surface after thermal treatment differs from the surface of unburned diatomite in that it becomes more active and has a 3–4 times higher increase in strength. Modified diatomite and expanded perlite sand have low thermal conductivity, and this property was used in the creation of building thermal insulation mixtures, which was confirmed by research, as the thermal conductivity coefficient ranged from 0.128 to 0.152 W/m °C. The developed dry thermal insulation lime–cement mixture is intended for both interior and exterior finishing works, which is confirmed by the results obtained for determining the frost resistance of the solution and the frost resistance of the contact zone, and corresponds to the F35 grade and has a strength of up to 3.59 MPa.

The growing demand for low-carbon cementitious materials has increased interest in natural zeolite as a supplementary cementitious material capable of reducing clinker consumption while modifying cement system performance. This study presents an integrated experimental evaluation of natural zeolite-modified cementitious materials by combining rheological behavior, hydration, compressive strength, density, scanning electron microscopy (SEM), and X-ray diffraction (XRD) within a single experimental framework. Natural zeolite was used as a partial replacement for cement at dosages of 5–12.5 wt.%. The results showed that zeolite significantly affected both fresh-state and hardened-state properties. Zeolite increased the rheological resistance of fresh mixtures, shifted the exothermic hydration peak from 12 h to 8–10 h, and reduced the maximum hydration temperature by approximately 8–12%. Among the investigated compositions, the mixture containing 7.5% zeolite exhibited the highest compressive strength (44.9 MPa at 28 days) together with increased hardened density, suggesting more efficient particle packing and matrix development than the reference mixture. SEM observations indicated a more uniform distribution of hydration products in mixtures containing moderate zeolite dosages, while XRD analysis confirmed changes in the crystalline phase assemblage associated with zeolite incorporation. The results demonstrate that moderate natural zeolite replacement, particularly at 7.5%, provides an effective balance between rheological behavior, hydration characteristics, mechanical performance, and microstructural development, highlighting its potential as a sustainable supplementary cementitious material for low-carbon cement-based composites.

Research into lightweight structural concrete using volcanic tuff is of great importance to the construction industry. These materials have excellent thermal insulation properties, which helps improve the energy efficiency of buildings. A three-factor experimental design was used to build the statistical model. The test methods used were methods for determining the crushability of volcanic tuff, determining the average density, compressive strength and thermal conductivity of lightweight structural concrete. The influence of basalt fiber on the properties of lightweight structural concrete has been determined. The optimal compositions of lightweight structural concrete using tuff have been selected. The compressive strength of lightweight structural concrete reached 32.0 MPa. The average density range is 1754.6–2114.0 kg/m³. Good thermal conductivity values were obtained in the range of 0.653–0.818 W/m·K. The article obtained the optimal compositions of lightweight structural concrete using volcanic tuff as a filler.

The article presents the results of developing lightweight structural concretes based on ash-slag waste from the Almaty Thermal Power Plant-2. The ash-slag aggregates were produced using both firing and non-firing (clinker) technologies. The fired aggregates, obtained with the use of bentonite clay, exhibited a bulk density of 530–640 kg/m³ and a strength of 1.8–4.8 MPa. The non-fired aggregates based on Portland cement had a density of 644–690 kg/m³ and a strength of 1.79–2.98 MPa, while those based on liquid glass showed a density of 562–642 kg/m³ and a strength of 1.93–3.8 MPa. Using the obtained aggregates, lightweight concretes with a density of 1210–1750 kg/m³ and a strength of 100–152 kg/cm² were produced, meeting the requirements of GOST 25820-2014. In the compositions without coarse aggregate, the influence of additives such as CaCl₂, superplasticizers, and basalt fibers on the properties of ash concrete was studied. The strength of the concrete after 28 days exceeded the 7-day strength by 1.5–2.3 times, with the most significant effect observed from CaCl₂. Ash concrete of classes B10–B12 with a density of 1500–1600 kg/m³ was obtained, which according to GOST can be classified as structural-thermal insulating concrete. The objective of the research is to develop compositions of lightweight structural concrete based on ash-slag waste. The novelty of the work: for the first time, ash-slag aggregates based on the ash-slag from Almaty Thermal Power Plant-2 have been obtained using both firing and non-firing technologies.

The study proposes a fractal model based on B. Mandelbrot's geometry. Mandelbrot geometry to describe the scale effect in concrete. It has been experimentally established that under-loading concrete undergoes degradation of its structure, which is expressed in the sequential destruction of fractals at different scale levels. It was found that the scale reduction leads to an increase in concrete strength: 20x20x20 mm specimens showed the highest strength among all four compositions (23.3-25.3 MPa). The average density of tuff concrete was also investigated: the smallest specimens had a density of 1961.3 kg/m³, while the largest specimens had a density of 1974.2 kg/m³, which is explained by the heterogeneity of the structure and pore distribution. The water permeability of concrete, evaluated through air permeability, showed that specimens with higher air permeability (30.2-30.5 s/cm³) had better water resistance (W14). These data indicate a correlation between air permeability and water resistance, which may be due to the denser structure and improved pore distribution. The study of air permeability makes it possible to predict the durability of concrete structures when exposed to moisture, as well as to improve the quality of building materials and reduce the cost of their operation.