Proportion Of Aggregates Research Articles

ANALYSIS AND DESIGN OF STONE MATRIX ASPHALT

Stone Matrix Asphalt (SMA) firstly developed in Germany in 1960. And it has been implemented by many countries for Flexible Pavement Road Construction. It is highly rut-resistant of bituminous coarse for heavy traffic roads. In April-2006 the indian road congress (IRC) decided for specifications be developed for SMA. The specification of SMA approved by the IRC council in 2007. Stone Matrix Asphalt has been proposed as a wearing course for the pavement. And carried out to meet the specification as recommended. The marshall method was adopted for design and analysis of mix as described in the Asphalt Institute Manual MS-2. The basic principle of Mix-Design is to arrive at Optimum Binder Content at the selected and mechanical properties desired. The suitable ingredient is the most important for the deign of SMA. To make an appropriate design with Aggregate, Filler, Bitumen, Cellulose Fiber and Additive. Stone Matrix Asphalt have a higher bitumen content which hold the aggregate with resistivity. Therefore rutting to be minimize and provide a higher rut resistant stability to the pavement under the heavy road traffic or heavy loaded vehicle. In this Mix-Design coarse aggregate proportion is high which can be optimize and prevent to the rutting. The temperature of mix material and all the individual material like, Aggregate, Bitumen, Cellulose Fiber are very sensitive as per actual, because required compaction will achieve when the temperature of all remain within specified.

Unit Weight and Elastic Modulus of Concrete utilizing Volcanic Stone Waste as Coarse Aggregate

Unit weight and elastic modulus of concrete utilizing volcanic stone waste (VSW) as coarse aggregate have been studied at 28 days of hydration. The origin of VSW was the residual of volcanic stone processing for making the handmade ornaments of traditional Balinese buildings. Three types of concrete mixture compositions were made by varying the proportion of cement, fine aggregate and coarse aggregate in concrete. Each mixture composition stirred using four variations of water/cement (w/c) ratio. For each variation in w/c, five cylindrical specimens with a diameter of 150 mm and a height of 300 mm were made to measure the unit weight and modulus of elasticity of concrete specimens after 28 days of hydration. The result shows that the unit weight and the elastic modulus of concrete decrease with increasing w/c at fixed proportions of cement and aggregates and increase with increasing proportion of aggregates at fixed w/c. The increase in elastic modulus with an increase in the a/c ratio for a fixed w/c ratio is more noticeable for a w/c ratio of more than 0.6. Moreover, the elastic modulus increases correspondingly with an increase in unit weight for a given a/c ratio.

Influence of gradation on extrusion-based 3D printing concrete with coarse aggregate

Coarse aggregate is an indispensable component of concrete, the gradation of which plays an important role in the properties of concrete due to its effect on particle distribution. The extrusion-based 3D concrete printing (3DCP) has become a promising technology while the influence of coarse aggregate gradation on the material design and performance of 3D printed concrete still lack understanding. This study experimentally investigates the fresh and hardened properties of 3D printed concrete with 4.75–20 mm continuous and discontinuous grading coarse aggregates, including flowability, buildability, axial compression, and drying shrinkage. The results reveal that 3D printed concrete with continuous grading performs better on flowability retaining and multilayer structure stacking than that with discontinuous grading. The evaluation coefficient of aggregate particle size is proposed to characterize the average particle size of coarse aggregates with different gradations, which shows linear relationship with coarse aggregate 3D spacing in 3D printed concrete. The current axial compressive stress–strain model for the conventional concrete prediction curve is modified to predict the effect of coarse aggregate gradation on constitutive relationship of 3D printed concrete. The increasing proportion of large-sized coarse aggregates can lead to a reduction in long-term drying shrinkage of 3D printed concrete.

Thermo-Physical Characterization of Waste-Glass-Induced Packed Bed Material as Thermal Energy Storage Device for Compressed Air Energy Storage System

Abstract The article presents the preparation and testing of packed bed (PB) material to be used as a thermal energy storage (TES) device. The proposed TES device will be used to store the high thermal energy attained during air compression in a compressed air energy storage (CAES) system. The article examines the utilization of mortar-based admixture by incorporating waste glass powder (WGP), graphite powder (GP), and waste glass sand (WGS). The selection of these constituents as a primary ingredient for the PB material has been made based on their availability, cost, and sustainability. The thermo-physical assessment of samples with different proportions of aggregates outlined two categories of PB: the first category of PB with low volumetric heat capacity (CP) for short/quick TES and the second category of PB with high CP for large/longer TES. The study also showcases the importance of GP in enhancing the CP of mortar-based TES devices as a result of high porosity.

Clarifying the effects of volume proportion and surface area of aggregate on chloride diffusivity of concrete through microstructural design

Increasing the aggregate proportion usually reduce the chloride diffusivity of concrete, but may also increase the chloride diffusivity as more interfacial transition zone (ITZ) is introduced with increased surface area of aggregate. Since both packing density and surface area of aggregate varied simultaneously with its particle size distribution (PSD), effects of volume proportion and surface area of aggregate on the chloride diffusivity of concrete has not been clarified separately yet. In the present study, we established a database containing over 500,000 aggregate PSDs and their corresponding packing density and specific surface area using the Compressible Packing Model (CPM) and photogrammetric 3D reconstruction. By individually controlling target volume proportion or surface area of aggregate, effects of aggregate volume proportion and surface area on the mechanical properties and chloride diffusivity of concrete were evaluated. Then an empirical equation, in consideration of aggregate size-dependent ITZ thickness the tortuosity, was proposed to describe the relationship between chloride diffusion coefficient and aggregate proportion and surface area, and a strategy for aggregate PSD optimization was provided to meet chloride diffusivity requirement, which offer an approach for enhancing the chloride resistance of concrete.

Virtual-specimen modeling of aggregate contact effects on asphalt concrete

Aggregate contacts significantly affect the mechanical behavior of asphalt concrete. However, there still lacks an effective way to account for them in numerical modeling. Therefore, to address this concern, a new virtual-specimen-based modeling approach was developed in this study by simplifying aggregate particles in asphalt concrete as spheres and incorporating aggregate contacts through Contact Region (CR) elements. The complex moduli of both gap-graded and dense-graded mixtures were predicted using this approach and compared with those predicted using the conventional image-based modeling approach and laboratory-measured values. The virtual-specimen modeling revealed that the CR in the gap-graded mixture with a higher proportion of large aggregates can better transmit load among aggregates than in the dense-graded mixture. Both modeling approaches were found to provide good prediction accuracy, but the stress distributions in the virtual-specimen models were more uniform and continuous, leading to better computational convergence and the possibility of nonlinear analysis of asphalt concrete.

Grazing Decreases Soil Aggregation and Has Different Effects on Soil Organic Carbon Storage across Different Grassland Types in Northern Xinjiang, China

Soil aggregates, as the basic component of soil, make great contributions to the stability of soil structure and soil carbon (C) sequestration. Recently, grasslands have been experiencing continuous grazing, which has had a significant impact on soil aggregation and soil C storage. However, how soil aggregates and soil C in different grasslands respond to grazing remains unclear. Therefore, three national fenced grassland-monitoring sites that represented mountain meadow (MM), temperate steppe (TS), and temperate steppe desert (TSD) were selected to investigate the differences in the responses of soil aggregates and soil C among grazing of different types of grasslands. Soil samples of 0–10 cm was collected from both inside and outside the fence of each site to analyze soil properties and soil aggregate characteristics. The results showed that soil nutrients varied greatly among the three grassland types, with the highest values in MM. At each site, grazing increased the content of sand and decreased the contents of silt and clay compared to fenced plots. Soil aggregate composition showed significant responses to both grassland type and grazing, especially the proportions of soil aggregates >2 mm, which significantly decreased by 51.7% on average in grazing plots compared with fenced plots. A significant decrease (on average, 25.1%) in the mean weight diameter (MWD) of soil aggregates under grazing was detected across all grassland types. The effect of grazing on nutrients in macroaggregates (>0.25 mm) was greater than that in microaggregates (<0.25 mm). Aggregate-associated SOC concentration decreased under grazing in MM and TS. However, grazing had no significant influence on the SOC density of MM, while it led to a significant decrease in TS and an increase in TSD. The magnitude of grazing effect size on aggregate-associated SOC varied with different soil particle sizes, with greater responses in aggregates >2 mm and the biggest value in TDS. In addition, the results of the correlation analysis and redundancy analysis (PDA) indicated that soil bulk density and nutrients made the main contribution to soil composition and stability of soil aggregates. Overall, grazing had a significant influence on soil aggregation, stability, and SOC, playing a crucial role in grassland soil stability and the accumulation of SOC.

Scheffe's Polynomial Optimisation of Laterite Concrete Incorporating Periwinkle Shells and Coir

Recent emphases on minimising the carbon footprint of concrete have focused on the use of non-conventional materials for the production of low-cost concrete. Such materials include laterite, periwinkle shells and coir which have been reported as suitable for use as fine and coarse aggregate replacements in specified proportions. However, the use of two or more unconventional materials in a concrete mix would require significant experimental effort that is time- and resource-consuming and usually performed by trial and error to determine the optimum mix design. A popular optimisation technique used for concrete mix design is Scheffe's second-degree polynomial modelling. However, the application of a more accurate Scheffe's third-degree polynomial optimisation technique in designing cementitious composites incorporating unconventional aggregates is rare. This study, therefore, presents the use of Scheffe's third-degree model to determine the optimum proportions of coir, laterite and periwinkle shell aggregates in a concrete mix in order to obtain the best mechanical properties of the hardened concrete. The constituents of the concrete were optimised for seven components of water, cement, fine-aggregate, laterite soil, coarse aggregate, periwinkle shell and coir on an N(7, 3) Sheffe's factor space. The optimal mix ratio for compressive and flexural strengths of 11.33 and 1.20 MPa, respectively, was 0.5149, 1.044, 3.009, 0.126, 3.934, 0.054, and 0.0046 for pseudo-components Xi: {∀i = 1, 2 3, 4, 4, 6, 7}. The coefficients of determination (R2) were 98.74% and 98.53% for the compressive and flexural response models, respectively, while the p-values obtained for the response coefficient fit parameters βi, βij, βijk for (i = 1, 2, 3, 4, 5, 6, 7) were 96.77% and 91.49% for the compressive and flexural strength models, respectively. The optimised Low-Performance Concrete (LPC) is about 4% cheaper than LPC made from conventional aggregates and is adequate for patio slabs, pedestrian footpaths, kerbs, and floorings in residential buildings. The use of Sheffe's third-degree model eliminates the significant experimental efforts needed in the design of concrete mixes incorporating unconventional aggregates.

Anti-skid durability of porous drainage asphalt mixture based on discrete element

In order to improve safety indicators such as the skid resistance and durability of road, the discrete-element method is used to study the proportion of the asphalt mixture, and the spatial structure of the coarse aggregates and asphalt mortar are compared and analysed. Relevant models are established to compare their pendulum values and structural depth attenuation. When the fine aggregate is limestone and the surface polishing times do not exceed 3500 times, the 7/3S1 asphalt mixture has the best pendulum value. However, as the polishing times continue to increase, the mixture ratio also changes. Compared with the 7/3S1 asphalt mixture, the 8/2S1 asphalt mixture has better effect. When the fine aggregate is replaced by limestone, no matter what form the coarse aggregate is, the pendulum value has been improved to a certain extent comparing with the previous mixture. A2S2, 5/5S2, 7/3S2 and 8/2S2 blends, compared with A2A2, 5/5A2, 7/3A2 and 8/2A2 blends, the pendulum value was increased by 1.7, 0.5, 2.3 and 2.1%, respectively. The study shows that in different proportions of coarse aggregates, as the surface texture richness of the blended aggregate increases, the differences between the aggregates also increases, and skid resistance and durability are also enhanced. The research results provide a blending method to increase the skid resistance and durability of asphalt pavement.

Analysis of the shear behavior of reinforced recycled aggregate concrete beams based on shear transfer mechanisms

This study aims to contribute to a more rational understanding of the shear behavior of reinforced recycled (concrete) aggregate concrete beams. Twelve reinforced concrete beams - six with natural aggregate concrete (NAC) and six with 100% coarse recycled concrete aggregates (RAC) - with same concrete compressive strength (38 MPa) and proportions of cement and aggregates per volume, varying the longitudinal (1.15%, 1.75%, and 2.50%) and transverse (0%, 0.086%, and 0.114%) reinforcement ratios, were tested under a 4-point bending setup with a full-field displacement monitoring. A thorough examination of the failure span along the tests, associating critical crack shape and kinematics with an investigation of the shear transfer mechanisms provided by mechanical models from the literature was conducted. Direct shear tests on push-off specimens followed by analyses of their failure surface evaluated the characteristics of shear crack surfaces and a proper modeling of the aggregate interlock contribution. The results showed a 28% average reduction in the shear strength of RAC beams with no stirrups in comparison with their reference beams (NAC), whereas beams with stirrups of same characteristics showed a similar shear strength, regardless of the type of coarse aggregate. The evaluation of the shear transfer mechanisms enabled an understanding of the reasons for those behaviors. Experimental results were also compared with those predicted in design codes. They were conservative for beams with stirrups, and, in general, less accurate than those obtained by the shear transfer mechanisms.

The binder-aggregate interface in NHL mortar with non-calcitic aggregate: Physical properties

In the absence of resources of calcitic aggregates this work aimed to confirm the suitability of Scottish aggregates in NHL mortar. Strength, sorptivity, porosity and carbonation of mortars made with one siliceous and one felsic (granitic) aggregate have been studied. The results suggest that there are no technical barriers to their use and that environmental and philosophical considerations reveal positive benefits. The measured properties all depend on the relative volume proportions of binder and aggregate, even at constant water/binder ratio and the trends can be explained by considering the behaviour at the binder-aggregate interface.

Separation of bispecific antibody related impurities with mixed-mode chromatography

The complex structure of bispecific antibody molecules and the rapid increase in upstream expression pose a significant challenge for downstream purification. Compared to mAbs, bsAbs typically contain a higher proportion of aggregates and fragments that are difficult to remove. Extensive study and optimization are often required because the properties of impurities are close to the target molecules. In this investigation, ion exchange resins and mixed-mode resins were used to evaluate the effectiveness in removing byproducts. Mixed-mode anion chromatography was found to be effective in polishing step of bsAbs with strong hydrophobicity. Hydroxyapatite chromatography using arginine hydrochloride as an eluent provided excellent separation performance compared to that of cation exchange resins and conventional mixed-mode resins. The separation process was optimized and verified in a 200 L pilot batch. The final products were obtained with excellent purity (99.0 %) and yield (80.70 %). This work provides a new idea for high-yield polishing in downstream processing, which improves the economics of large-scale production.

Application of Desulphurized Gypsum with Straw to Improve Physicochemical Properties of Saline-alkali Land in Yellow River Delta

In order to explore the effect of combining straw and desulphurized gypsum on improving coastal saline-alkali soil, taking the alkaline saline soil in the Yellow River Delta as the research object, six treatments including the control (CK), desulphurized gypsum (DG), medium straw amount (MS), desulphurized gypsum+low straw amount (DGLS), desulphurized gypsum+medium straw amount (DGMS), and desulphurized gypsum+high straw amount (DGHS) were set up through a field location experiment. Combined with the aggregate classification method, the changes in bulk density, total porosity, pH, soluble salt content, microbial biomass carbon, dissolved organic carbon, new carbon, and aggregate organic carbon of coastal saline alkali soil under different treatments were compared. The results showed that the MS and DGHS treatments significantly reduced soil bulk density and increased soil total porosity, water content, and average weight diameter. The pH and exchange sodium percentage decreased significantly under all treatments, and there was no significant difference. DG treatment significantly reduced the soil sodium adsorption ratio. Compared with that in the MS treatment, the soil sodium adsorption ratio of DGLS, DGMS, and DGHS showed a further decreasing trend, with a decrease range of 57%-66%. Compared with MS, soil soluble Na+ decreased by 27.92%, 32.23%, and 20.15% under the DGLS, DGMS, and DGHS treatments, whereas the soil soluble Ca2+ and SO42- contents increased significantly. Compared with that in CK, all treatments could significantly reduce Cl- content, and there was no significant difference among all treatments. Compared with that in MS, microbial biomass carbon and dissolved organic carbon were significantly increased by 113% and 147% by DGMS and 22.81% and 28.24% by DGHS, respectively. The new carbon formation of DGLS, DGMS, and DGHS was 67%, 114%, and 175% higher than that of MS, respectively. The average size proportion of fine aggregates treated by DGLS, DGMS, and DGHS was 29.12% higher than that treated by MS. Straw returning and application of desulfurized gypsum increased the organic carbon content of coarse aggregates and fine aggregates in salinized soil. The average value of new carbon formation in coarse aggregates and fine aggregates treated by DGMS and DGHS was 233% and 142% higher than that treated by MS, respectively. Desulphurized gypsum applied to soil did not lead to soil heavy metal pollution, and the soil heavy metal content of different treatments was lower than the secondary standard of the soil environmental quality standard. These results can provide scientific basis for the improvement and utilization of coastal saline-alkali soil and the comprehensive utilization of industrial and agricultural wastes in the Yellow River Delta.

Distribution Characteristics of Heavy Metals in Different Particle Size Fractions of Chinese Paddy Soil Aggregates

In recent years, the migration and transformation of heavy metals (HMs) in soil has become a hot issue. Soil particle size has an important effect on the environmental behavior of HMs in soil. The distribution of HMs in soil is strongly affected by the size of a soil aggregate. In this study, paddy samples in both cultivated and uncultivated soils were collected from Anhui Province, China. The soils were sieved into six particle size fractions (diameters of >4000, 4000–2000, 2000–1000, 1000–250, 250–53, and <53 μm) and the wet digestion method was used to determine the concentrations of Cd, Cr, Pb, and As in the soil aggregates. The results showed that the surface soils were characterized by the largest proportion of coarsest aggregates of >4000 μm particles. Moreover, the concentrations of Cd, Cr, Pb, and As were elevated in cultivated paddy soils compared to uncultivated soils. The accumulation of HMs in all paddy soils increased with decreasing particle size. Although the smallest particle size fractions accounted for only 5.65–17.28%, they provided the highest distribution factor (DF) of Cr (1.35), As (1.25), Cd (1.28), and Pb (1.38). The highest contributions of HMs came from the coarser fractions (>2000 μm); however, for Cr, Pb, Cd, and As, the mass loading of <53 μm particles was up to 15.90%, 14.41%, 15.21%, and 15.70%, respectively. The highest content of HMs was found in the finest aggregate, with a pattern of decreasing with increasing aggregate size. In addition, the leachability behaviors of different HMs in different particle size aggregates were different. The leachability behaviors of Cr and Pb in the coarse particle size fractions were the highest, while the leachability behaviors of As and Cd in the less than 250 μm particle size fractions were 10–100 times higher than those of Cr and Pb. A correlation analysis showed that the particle distributions of Fe, TOC, and Mn had significant influences on the distributions of Pb, Cd, As, and Cr. This study provides a theoretical basis for the prevention, treatment, and remediation of HMs pollution in soil.

The legacy effects of soil types on carbon content are erased by extreme flooding stress in a water-level drawdown zone

Soil carbon dynamics are closely related to pedologic properties and highly variable among different soil types, however, it is not clear if the effects of soil types on carbon storage can be erased by a continuous environmental stress. Periodic flooding, the dominant environmental stress on natural riparian habitats, greatly regulates the biogeochemical cycles of carbon. To reveal how flooding stress affects carbon storage within different soils, here, we have examined soil types’ effects on carbon storage along a flooding gradient in the riparian zones of the Three Gorges Reservoir. The two-way ANOVA analysis was applied to measure the effects of soil type, flooding stress, and their interactions on aggregate proportion, organic carbon fraction, carbon concentration, and content in aggregates and bulk soils. The partial least squares path model was used to uncover the potential mechanisms of flooding stress affecting carbon storage for different soils. The results presented that the topsoil of the riparian zone of the Three Gorges Reservoir holds exceeding 3.95 Tg of carbon. Anthorosols, Luvisols, and Regosols stored 351.02, 275.50, 1349.50 Gg C, respectively. Flooding stress was found to positively affect C content for Anthrosols and Regosols with total effect sizes of 0.52 and 0.59, respectively. However, flooding stress had a negative impact on C content in Luvisols. In addition, the effect sizes of soil types on C content were alleviated by the strong flooding stress, and the effect size at the control and weak stress levels were higher than that at strong and intermediate stress levels. The original heterogeneousness of soil physical properties within different soils was homogenized by the extreme flooding stress, which can be indicated by aggregate proportion and particulate organic carbon.

Physical and mechanical properties of locally fabricated geopolymer-plastic ceiling boards

The 21st century has seen a rise in the demand for building materials, which is not unconnected to the rise in population. The high demand has led to an increase in the price of such commodities as well as a strain on environmental resources and the call for more sustainable, and cost-effective alternatives to replace the conventional materials. In this study, waste glass powder was alkali-activated to produce geopolymer, which was combined with both fine and coarse waste polyethylene terephthalate (PET) pulverized plastics (aggregates). The product was then cured to form the ceiling board. The impact of the employed glass, alkaline solution, aggregate size, and aggregate content in the boards were then investigated. Board J with 92.5% PET particles (Coarse and Fine) and 7.5% Glass Particles gave the best water absorption (16.561%), thickness swelling (3.332%) and density test (0.918 g/cm3) results. It was found that the geopolymer with equal proportions of fine and coarse PET aggregates reduced the material's ability to absorb water and increased its density and swelling thickness. The modulus of rupture and modulus of elasticity of the boards were both enhanced by adding more glass powder and fine PET aggregates. However, it was discovered that the board's mechanical qualities, unlike its physical properties, were not improved by the addition of the geopolymer during manufacture.

Experiment investigation on mix proportion optimization design of anti-cracking stone filled with cement stabilized macadam

Semi-rigid base asphalt pavement is widely used in China for asphalt pavement construction. However, the presence of reflection cracks remains a significant issue associated with semi-rigid bases. Large Stone Filled with Cement Stabilized Macadam (LSFC) has been identified as an effective solution for inhibiting reflection cracks. However, the construction of LSFC using large particle size coarse aggregates can be challenging. Additionally, the existing mix design process lacks clarity and results in low strength. This paper aims to optimize the design method for anti-cracking Stone Filled with Cement Stabilized Macadam (SFC) by selecting appropriate materials and improving design process. Initially, a mix proportion for SFC is designed using coarse aggregates with common particle sizes employed in engineering applications. The filling proportion of the coarse aggregates, cement dosage, and mass proportion of the cement mortar are gradually determined through compaction and 7-day unconfined compressive strength tests, resulting in the complete mix proportion for SFC. Subsequently, the strength performance, fatigue performance, dry shrinkage performance, and temperature shrinkage performance of SFC are evaluated and compared with common Cement Stabilized Macadam (CSM). The results indicate that while the strength and fatigue properties of SFC are slightly inferior to those of common CSM, it exhibits superior dry shrinkage performance. Moreover, SFC demonstrates better overall crack resistance compared to common CSM, despite having slightly inferior temperature shrinkage performance.

Aggregate size characterisation and porosity analysis of granular mixtures

ABSTRACT This paper aims to explore the correlate relationship between particle size composition and porosity of particles and reveal its influence mechanism. First, aggregate particles were divided into coarse aggregate, medium aggregate and fine aggregate. Combination of the particle size ratio and mixing proportion of each grade aggregate were used to characterize the particle size distribution. Second, a mixture proportion triangular coordinate system was proposed; and a series of void ratio contour maps of granular mixtures were plotted in the coordinates based on results of the discrete element numerical simulation test. Finally, correlation between mixture composition and porosity has been analysed. It was found that (1) The void ratio of mixtures with different particle size ratio combinations is mainly different from the size and distribution. (2) Both proportion and particle size composition of coarse aggregate are main factors affecting the change of porosity. (3) For mixtures with the maximum particle size of 16 mm, various particle size ratios within that definition of coarse aggregate are possible. Suitable combination schemes of particle size ratio for each grade of aggregate are recommended for the gradation evaluation and design. (4) The relationship between gradations and voids for the granular mixtures has been established and quantitatively characterised..

Quantitative Characteristics of the Microstructure of Typical Chernozems Using Different Agricultural Technologies

The methodological possibilities of micromorphological soil research making it possible to analyze digital images of soil thin sections at a quantitative level are presented in this study. A new software Thixomet Pro has been tested for quantitative micromorphological study of sail on the example of soil thin sections from the surface horizons of Haplic Chernozem. Soil samples for preparing thin sections were collected on the territory of scientific and industrial field test plot for assessing the impact of agro technologies in grain crop rotation on soil properties (Kursk region, Russia). In the field test plot, conventional agro technology (real tillage) and no-till are compared. Soil sampling was carried out in two replications from depth of 10–15 cm. The analysis revealed the variability of microstructure of Haplic Chernozem in the size, shape and orientation of aggregates associated with the use of agricultural technologies with and without plowing in grain crop rotation. In the Сhernozem with no–till, aggregates are generally larger compared to the aggregates of Сhernozem with conventional agro technology. This is noted at all levels of comparison of direct seeding and conventional agricultural technology: in the minimum diameter, the fraction 1–2 mm prevails against 0.25–0.5 mm, respectively, in the average diameter, fractions 1–2, 2–3 and 3–5 mm prevail against 0.5–1 and 0.25–0.5 mm, respectively, in the maximum diameter, fractions 1–2, 2–3 and 3–5 mm prevail against 0.5–1, 0.25–0.5 and 1–2 mm, respectively. It is also shown that less rounded and isometric aggregates are formed during direct seeding. With direct seeding, the proportion of aggregates with a form factor of 0.2–0.4 is higher and the proportion of aggregates with a form factor of 0.4–0.6 is lower than with traditional technology. The proportion of subhorizontal aggregates in direct seeding is higher compared to traditional processing (54.3 and 34.1% respectively).

Review of geopolymer concrete in high grade infrastructure construction

The construction industry must ensure a new occupant experience that is connected, safe, and comfortable. Due to its versatility, concrete is the most frequently used building material worldwide. Cement is an essential ingredient of concrete, but it is not considered environmentally friendly. The production of Portland cement consumes a considerable amount of energy and emits a significant amount of carbon dioxide. By creating and utilizing alternative materials, like geopolymers, construction may become much more sustainable. Cement production has a significant environmental impact, which must be reduced by developing new binder types. With the use of various industrial byproducts, the workability, impacts of temperature change, usage of admixtures, use of fibers, and effects of the water-binder ratio of geopolymer concrete are all investigated. It indicates that the regulated geopolymer concrete mix's compressive strength is inferior to that of geopolymer concrete with additional hooked-end steel fibers. As a recent innovation in concrete, Geopolymer is a substance in which fly ash, which is activated by an alkaline solution to act as a binder, completely replaces cement. Geopolymer concrete was analyzed with different ratios of activators for strength analysis. To select the correct ingredients for geopolymer concrete to achieve the desired strength at the desired workability, the grading of geopolymer concrete following the Indian Standard Code has been the subject of experimental effort. Assessing the amount and fineness of fly ash, the amount of water, or the amount of alkaline liquid is a step in the mix design process, along with the W/C ratio, fine aggregate quality, fine aggregate proportion to total aggregate, and superplasticizer content. Premixed geopolymer concrete's compressive strength, shear strength, flexural strength, and bonding strength will be evaluated after the materials' internal reactivity has been verified.