Concrete Composites Research Articles

Experimental investigation of effects of multi-fissures on brittleness of ordinary Portland cement concrete and rubberized concrete

The Brittleness index of concrete is related to both confining pressure, ambient temperature, its components and internal defects, especially all types of fissures. In the paper, the experiments were conducted to investigate the relationships between brittleness index and concrete composition and flaws under uniaxial compression through the brittleness index of OPC (ordinary Portland cement concrete) and RC (rubberized concrete) containing multi-fissures. The results show that the relationship of brittleness index and concrete composition is positive to brittleness index change of OPC and RC containing multi-fissures. The brittle index of OPC is 18.3% higher than that of RC which replaced 10% sand by rubber power. As for OPC containing two fissures, the brittleness index is lower 48.8% than that of intact specimens and the specimens containing 45°angle has the lowest brittle index among counterpart of RC. As for RC with parallel and non-parallel fissures, the brittleness of the latter is 18.8% smaller than that of the former. The brittle index of the RC with non-parallel fissures declines the most and largest damage. Finally, OPC and RC containing fissures contribute to their toughness and ductility if permissible. The reliability of the new index of brittleness can nicely enrich and improve the existing evaluation methods of concrete brittleness.

Numerical modeling of shrinkage induced cracking in cementitious materials with three-dimensional simulation and phase-field method

This study investigates the damage and cracking of concrete induced by drying shrinkage. While previous studies have primarily focused on two-dimensional configurations, this research employs three-dimensional phase-field simulations of concrete samples undergoing the drying process. The distribution of inclusions is derived from tomographic images of real samples. The analysis includes the evolution of the damage field and the propagation of cracked zones. The study introduces the formulation and implementation of the numerical method and applies it to elucidate the cracking process resulting from drying shrinkage in concrete composites with various types of inclusions. Numerous numerical simulations were conducted to accurately depict the cracking process induced by drying shrinkage in the samples, evaluating the effects of different inclusions with varying stiffness on the concrete’s cracking phenomenon and comparing the impact of various energy degradation methods on crack simulation. Moreover, the study analyzes the influence of the spatial distribution of the inclusions in the three-dimensional simulation and compares the numerical results with experimental observations.

Investigation of Materials for Enhanced Vibrational Insulation in Ground Structures Using Concrete Mixtures: A Case Study of Rubber Aggregate Addition.

The reduction of vibrations in concrete has been a topic of discussion among scientists. This article presents research on designing concrete mixes for constructing ground barriers with enhanced vibration isolation using waste materials. This study discusses the design of concrete mixes for the construction of concrete partitions with increased vibration isolation, using the polish standards. The experiments were conducted at the Laboratory of Building Materials Engineering at the Cracow University of Technology as part of the project entitled "Innovative construction of vibration-insulating barriers to protect the environment from transport vibrations and similar sources". The concrete composition utilized blast furnace cement CEM III/A 42.5 N, with mineral and chemical additives. Recycled rubber aggregate from used tires was employed to enhance vibration isolation. Measurement results demonstrated the effectiveness of the concrete in dampening vibrations, confirming its suitability for practical use.

SO SÁNH CƯỜNG ĐỘ CHỊU NÉN CỦA BÊ TÔNG SỬ DỤNG CỐT LIỆU TÁI CHẾ VỚI BÊ TÔNG THÔNG THƯỜNG, TRƯỜNG HỢP CÓ SỬ DỤNG TRO BAY VÀ KHÔNG SỬ DỤNG TRO BAY

This article presents the results of research evaluating the compressive strength of concrete using recycled coarse aggregate, in the case of using fly ash (CP1) and without using fly ash at a content of 5% (CP2). The experimental samples were compressed to test the compressive strength value at different times, including 7 days old, 14 days old and 28 days old. The study designed a recycled concrete composition with a 50-50 ratio of regular aggregate and recycled coarse aggregate, and the concrete has a design compressive strength of 15 Mpa. The compressive strength of concrete was studied and compared in cases with and without fly ash, and compared with another research result on concrete using recycled coarse aggregate.

Synergising hybrid short fibres and composite cements for sustainable and efficient textile-reinforced concrete composites

Under the raising concerns over the environmental impacts of construction materials, including reinforced concrete, there has been a recent growing focus on the application of innovative Textile Reinforced Concrete (TRC) composites to the repair of existing deteriorated structures or to developing slender structural components. Aiming to further increase the attractiveness of TRCs, we focus on the development of low-carbon, cost-effective and ductile TRCs from Alkali Resistant (AR)-Glass textiles and composite cements with a focus on the reduction of the clinker content and incorporation of short fibres into the TRC matrix. Quaternary blends of cement and Supplementary Cementitious Materials combined with single and hybrid short fibres of alkali-resistant glass, Polyvinyl alcohol, and polypropylene, are considered for this purpose. The role of these in controlling the post-cracking response, load carrying capacity and mechanical behaviour of TRCs is investigated. These followed by an environmental and cost analysis show that the developed TRCs exhibit significant improvement in ductility and nonlinear response, and reduction in cost and embodied carbon compared to those available in the literature. It is also shown that the hybridisation of short fibres allows manipulating the performance, carbon footprint, and cost of hybrid TRCs.

Stochastic fracture of concrete composites: A mesoscale methodology

The accurate prediction of concrete composites’ fracture behaviour requires precise meso-structural characterization, appropriate fracture modelling, and pivotal uncertainty assessment. Towards this goal, we adopt a dynamics approach with CT images to generate numerical concrete models using real aggregates with 30%-60% contents. An image slicing method is then developed to obtain a large number of realistic models in 2D, whose heterogeneity is characterised by aggregates, mortar and interfaces. Monte Carlo simulations of uniaxial tension are performed, incorporating cross-scale fracture evolution through a phase-field cohesive zone model. Statistical analyses reveal that the stochasticity of crack patterns and stress-displacement curves, especially post-peak softening responses, is inherently dependent on the random meso-structures. It is observed that increasing aggregate content accelerates the deterioration rate of peak stress, decreases the softening curve, and leads to more tortuous crack paths, considering the ITZ crack channels. On the other hand, the tensile strength of mortar has significant impacts on the load-carrying capacity, while the fracture energy primarily influences the ductility and has negligible effects on the peak stress and the pre-peak nonlinear part. Besides, the ratios of mortar-ITZ tensile strength and fracture energy are found to affect the crack paths. The proposed numerical framework holds promise to reveal complex fracture mechanisms of concrete with more insights into other loading or environmental conditions.

TECHNOLOGICAL ASPECTS OF PRODUCTION OF EPOXY ASPHALT CONCRETE BY ADDING CARBON ADDITIVES

Epoxy asphalt concrete is a durable, high-quality material consisting of epoxy resins, hardeners, and the mineral part itself. Accordingly, slow-hardening epoxy asphalt concrete has high physical properties and low sensitivity to temperature changes, which makes it usable as a rigid pavement and applicable even on metal and concrete bridge decks. However, a downside of epoxy asphalt concrete is its ability to gain strength over a long period of operation (up to 1 year). It is a disadvantage when using such coatings in the upper layer of the road surface. In addition, a long period of strength gain during intensive use of the road pavement leads to critical destruction of the pavement itself, plastic deformation, and a reduction in the service life (which may differ much from the standard). Using metal fibre substantially increases the strength and keeps the area from collapsing. The use of metal elements can significantly reduce the performance of the tires of vehicles that will drive on the road and even create a hazard in the event of destruction of the epoxy asphalt concrete area. Using epoxy binders notably increases the strength characteristics of road materials, especially at high temperatures, and boosts their ability to resist rutting. At the same time, the characteristics of epoxy concrete do not decrease during operation and at low temperatures, which indicates the versatility of such a material. The only drawback that cancels out all the positive features of epoxy asphalt concrete is its long strength gain. This disadvantage not only led to the problems mentioned above but also delayed the opening of traffic, which, especially on roads of higher categories, caused traffic disruption and inconvenience to the movement of vehicles. The authors proposed a solution to this problem by developing an improved epoxy asphalt concrete composition by introducing fibre ash into the developed composition as a reinforcing and structuring additive that accelerates the pavement formation time and strengthens the asphalt matrix in epoxy asphalt concrete. Keywords: epoxy asphalt concrete, additive, fibre, fly ash, combustion products.

Optimization of Aggregate Composition of Asphalt Concrete Mixtures to Ensure Maximum Density

high strength and stability of asphalt concrete, but also at ensuring optimal characteristics of its structure.The main principles for the optimization of the grain composition are based on the parameters of the size and shape of thе stone aggregate particles included in the composition of asphalt concrete mixtures. An in-depth analysis of the grain composition helps to achieve an optimal balance between coarse and fine fractions, which in turn ensures the stability and durability of the asphalt concrete pavement. The maximum density of an asphalt concrete mixture plays a key role, influen-cing its physical and mechanical properties and ability to withstand aggressive environmental influences and traffic loads. In addition, the density of the mixture significantly affects its resistance to static and dynamic loads and deformations, which is important for ensuring road safety. The paper provides an analytical review of the basic principles and methodology for determining the grain composition of fine-grained asphaltic concrete mixtures with grain sizes up to 10 mm in order to achieve their maximum density. Both domestic and foreign methods for optimizing mixture design parameters are considered. Based on the consideration of ideal mathematical curves the grain composition, the main regularity for fine-grained asphalt concrete has been established, which has similar parameters to the mathematical Fourier curve. Understanding and practical application of the principles of constructing the grain composition of asphalt concrete mixtures of maximum density not only improves the quality of road construction, but also contributes to a more efficient use of resources, ensuring the stability and durability of the pavement. This leads to a reduction in road maintenance and repair costs, which is an important aspect in the context of the economic efficiency of infrastructure projects. Thus, improving the methods for investigating and controlling the grain composition of asphalt concrete is important for the sustainable development of road construction.

Research to evaluate the possibility of using sea sand to make roller compacted concrete as a surface layer for rural roads

In this period of very scarce river sand resources for construction activities, the use of sea sand and salt-contaminated sand to replace river sand in roller-compacted concrete is necessary and suitable to the needs of actual demand. This article presents some research results on the possibility of using the sea sand of "Can Gio" to produce roller-compacted concrete for rural road surface layers. The roller-compacted concrete mix composition is designed according to ACI 211.3R standards with a fly ash-to-cement ratio by volume of 0.3. The required compressive strength value of the roller-compacted concrete sample is 27 MPa at the age of 28 days. The technical requirements of roller-compacted concrete using sea sand have been evaluated including the hardness of the concrete mixture, compressive strength, and abrasion resistance of tested concrete, using the ratio of sea sand- aggregate by volume ranges from 0.41 to 0.50. The study also compared the physical properties of "Can Gio" sea sand according to the technical requirements of standard TCVN 13754:2023 to provide recommendations when using salt-contaminated sand and sea sand for roller compacted concrete mixture.

An Outstanding Engineer, Scientist, Teacher — Alexander Matveevich Ivanov. To the 110th Anniversary of His Birth

The scientific works of an outstanding scientist, A.M. Ivanov, devoted to the development of new methods for calculating wooden elements taking into account the time – creep factor have so far aroused great interest among modern researchers. The Voronezh Scientific School of Polymer Concrete A.M. Ivanov has substantiated and created universal models called “structural diagrams”, which lay the probabilistic foundations for evaluating the properties of materials, as well as polymer concrete and other composites. The article describes the life path, the formation of scientific activity and teaching of an outstanding scientist, Dr. of Technical Sciences, Professor A.M. Ivanov, a participant in the Great Patriotic War. Grateful students and followers showed that the issues of reinforcement of steel-polymer concrete structures, anchoring of reinforcement in polymer concrete and calculation of joints of prefabricated steel-polymer concrete structures of solid and annular cross-section with various types of reinforcement; the development of a whole range of polymer materials reinforced with fiberglass reinforcement and wood chips is the result of mentoring activities of an outstanding teacher and scientist.

Strength Indicators of Fiber Reinforced Concrete with Carbon Nanomaterials

Concrete composites with low defects, dense and homogeneous, with a high degree of adhesion between the cement matrix and aggregates, as well as a high ratio between static tensile and compressive strengths and plasticity have the best crack resistance characteristics. This ratio increases in the case of the use of fiber-reinforced concrete. Modern research in nanotechnology focuses on the management of matter at the nanoscale level, which makes it possible to create materials with new properties. Due to the high aspect ratio, flexibility, high strength and rigidity, carbon nanotubes (CNTs) exhibit reinforcing properties. Due to their nanoscale features, CNTs interact with a complex network of calcium-silicate-hydrate binder (C – S – H), contribute to a decrease in porosity and compaction of the cement stone structure, increase the shear forces of matrix adhesion in the contact zone. Thus, there are all prerequisites to assert that fiber concrete with a cement matrix modified with carbon nanotubes will have the required high strength characteristics and crack resistance due to multilevel dispersed reinforcement and the efficient operation of fiber in a nanomodified concrete matrix. This article presents the results of testing samples made of cement stone, concrete and fiber concrete with carbon nanotubes. The presence of carbon nanotubes in cement stone contributes to an increase in compressive strength by 11 %, tensile strength during bending by 20 %. The test results of samples made of reinforced fiber concrete modified with nanocarbon materials have shown an increase in tensile strength during bending up to 109 %, tensile strength during splitting up to 82 %, axial tensile strength up to 78 %.

Performance Evaluation of M30 Grade Concrete Using Silica Sand as Partial Replacement of Cement in Concrete

Abstract: This study explores the improvement of concrete parcels, particularly strength and continuity, through the partial substitute of cement with silica fume (SF). The exploration addresses the environmental and health issues caused by artificial waste disposal, similar to covering ash and copper slag, by incorporating silica sand into concrete. A literature review reveals that SF significantly improves the mechanical and continuity characteristics of concrete, enabling the product of highperformance concrete suitable for these soundings. This paper investigates the strength parameters of concrete with 0 –15% SF relief in increment of 5%, comparing the results with conventional concrete. Findings indicate that the optimal compressive strength and split tens are achieved at 10% SF relief, beyond which strength decreases. This study aims to inform civil masterminds about the benefits of SF- modified concrete composites.

Impact of pore sizes and defects on C-S-H/epoxy bonding in wet conditions: A molecular dynamics analysis

Despite the recent advances in understanding the water ingress at the interface of calcium silicate hydrate and epoxy, there are still open questions regarding the pore size and defects' dependence on the structure, dynamic and mechanical properties of the interfaces. In this paper, molecular dynamics simulations are carried out for perfect and defective interface models consisting of C-S-H and epoxy resins, respectively. Gaps of different sizes between epoxy and C-S-H are filled with water molecules, with a maximum spacing of 2.79 nm, to investigate the effect of water ingress on the structural, dynamic, and mechanical properties of the interface. The results indicate that in the interface formed by the defective structure, the calcium ions responsible for providing strength have been transformed into a free state due to the influence of water molecules. Consequently, they lose their ability to bridge between the epoxy and silicate tetrahedra, leading to the inability to establish interfacial strength. The defective structure, with its larger surface area and increased interaction with water, is more susceptible to degradation, especially noticeable in the tensile simulations. Furthermore, the interactions between water and C-S-H are the primary factors influencing the microstructure and dynamic behavior of the interface. As the number of water molecules increases, the interface strength weakens. This work provides new insight into understanding the bonding mechanism of the C-S-H/epoxy interface with water ingress. It contributes to the design and development of FRP reinforced concrete composites.

Sustainable End-of-Life Tyre Management: A Comprehensive Analysis of Environmental Impacts and Crumb Rubber Integration in Composite Concretes

The research explores pollution prevention strategies associated with end-of-life tyres (ELTs) through sustainable practices, focusing on repurposing ELTs into crumb rubber (CR) for use in composite concretes for civil engineering applications. Three disposal approaches are considered: recycling into crumb rubber for use in cement composites to enhance acoustic properties, incineration for cement production, and landfill disposal. The study aims to assess the environmental impact of each method, particularly in terms of carbon dioxide (CO2) emissions during the recycling phase, utilizing the OpenLCA program for a comprehensive life cycle analysis. The primary objective is to provide insights into the sustainability of incorporating recycled rubber in concrete mixes as fine aggregate to improve concrete acoustic and shock absorbance properties. The research also gathers data on CO2 emissions from ELT incineration for cement production and the environmental implications of ELT’s landfill disposal. By comparing these three strategies, the study offers a holistic perspective on the environmental ramifications of ELT management. Notably, a recent study highlights the energy recovery and CO2 emissions from ELT incineration, demonstrating the potential benefits of recycling. The research identifies a gap in existing studies, emphasizing the need to consider the entire life cycle, including the transportation and use stages. Notably, the use stage significantly contributes to environmental impacts, with carbon emissions ranging from 550 to 840 kg CO2 eq., per car tyre. Additionally, a proposed inventory analysis method evaluates greenhouse gas emissions from Portland cement concrete pavement construction, revealing that raw material production accounts for most emissions. The findings of this research are providing valuable insights for policymakers, industry professionals, and environmentalists aiming for sustainable practices in the construction sector. By allocating a fraction of tyre production CO2 emissions to obtain raw material for concrete composites, the study suggests a potential avenue for reducing environmental impact. Further calculations using the OpenLCA program may refine these recommendations.

Investigation of Hydrophysical Properties and Corrosion Resistance of Modified Self-Compacting Concretes.

Improvement of hydrophysical properties and corrosion resistance of self-compacting concrete to the effects of alternate freezing-thawing and aggressive soils of Southern and Central Kazakhstan is of interest to a wide range of researchers from the side of practical application of the obtained results in construction practice. It is proposed to form a spatially reinforced fine crystalline structure of a cement matrix with the maximum dense packing by using a complex modifier (hyperplasticizer + polymer + microsilica + fibro fibers) in the composition of self-compacting concretes (SCCs). The introduction of the calculated amount of the above additives increases the operational reliability of the current SCC compositions, increasing the water resistance to W16, frost resistance to F = 500, increasing the compressive strength by 20%, and reducing the mass loss of samples during corrosion leaching to 50%. It has been experimentally established that the proposed addition of the complex modifier (hyperplasticizer + polymer + microsilica + fibro fibers) to the SCC composition allows obtaining self-compacting concrete of high quality with improved performance characteristics (compressive strength, water resistance, frost resistance, and corrosion resistance). Studies have shown that the complex modifier-modified SCC compositions have a high degree of resistance in aggressive environments and leaching corrosion. Based on the results of the conducted tests, it is possible to recommend the obtained SCC compositions for the production of building products working in the zone of alternating freezing-thawing and aggressive soils.

Effect of Construction Delays and the Preventive Role of Concrete Works Optimization: Systematic Literature Review

Delays in construction are a widespread global problem, leading to potential cost overruns and legal disputes. Additionally, delays can result in a decline in construction quality and loss of public trust. The aim of this study is to examine the effects of project delays in various regions and the preventive role of optimizing concrete works. Literature review and bibliometric analysis are carried out to determine global research trends. Findings show that optimizing concrete works can provide benefits such as cost savings, time savings, improved quality and safety, and environmental benefits. Optimization of concrete material composition is one of the most examined topics in this field. Based on the findings, construction firms have the potential to attain cost efficiencies while concurrently mitigating carbon emissions.

Performance based concrete quality assessment with gas permeability testing on site

In terms of sustainability and durability, performance-based design is becoming increasingly important for the quality assessment of concrete structures. Up to now, prescriptive approaches for concrete composition and processing and the determination of concrete strength on cast samples have primarily been used as quality assurance. As this does not take into account the quality and pore structure of the as-built concrete cover, which has a significant influence on durability as a protective zone against penetrating media, the conventional approach to quality control is not representative for this zone. In particular, the permeability of the concrete cover, which is largely dependent on the pore structure, is responsible for the ability of aggressive substances from the environment to ingress into the concrete and, depending on its quality, determines damage processes in the reinforced concrete, such as carbonation. For this reason, investigations to gas permeability on real structures are presented here, which include the possibilities and limitations of measuring and evaluating gas permeability as a durability indicator. Long-term observation was carried out on concrete walls of a motorway construction site, from a young concrete age of 14 days to a higher age of max. 800 days, in order to determine changes in the material structure of the surface area and to analyse their influence on the gas permeability. The concrete walls were treated in advance during hydration up to an age of 7 days with different curing times and types in order to simulate good, medium and poor concrete surfaces. Clear differences in the quality of the concrete cover could already be determined by means of gas permeability. The influence of the surface structure, the effect of the environment and the long-term development of the concrete structure on the permeability are also addressed in this work.

Enhancing M30 Grade Concrete: A Comparative Study of Hooked vs. Crimped Steel Fibers in Fly Ash Mixes

The realm of concrete offers vast opportunities for inventive applications, design, and construction methodologies, given its adaptability and cost-effectiveness. Its versatility in meeting diverse requirements has established it as a highly competitive building material. To address escalating structural demands and harsh environmental factors, new cementitious materials and concrete composites are continually being developed, followed by the need for enhanced durability and performance, as well as pressure to utilize industrial waste materials. The research explores the impact of incorporating fly ash and steel fiber into M30-grade concrete, alongside cement, coarse, and fine aggregate, through experimental methods, with the primary aim of determining optimal ingredient proportions for achieving desired strength. The study evaluates compressive strength variations with fly ash ranging from [10%] to [30%] while hooked and crimped steel fibers [ranging from 0% to 1.5%] in concrete, alongside cement, fine and coarse aggregate. Environmental considerations and the imperative to utilize industrial waste have significantly contributed to advancements in concrete technology and sustainability. Through meticulous analysis of results, meaningful inferences are made in relation to the strength attributes of fly ash fiber-reinforced concrete. Two sets of experiments were conducted, one altering fly ash content while maintaining fixed steel fiber content, and the other varying steel fiber content while keeping other parameters constant. The study aims to provide practical insights for engineers seeking cost-effective and sustainable building construction methods, adhering to specified norms (IS Code: 456-2000).

Geochemical implications of uranium-bearing thucholite aggregates in the Upper Permian Kupferschiefer shale, Lubin district, Poland

New inorganic and organic geochemical data from thucholite in the Upper Permian (Wuchiapingian) Kupferschiefer (T1) shale collected at the Polkowice-Sieroszowice Cu-Ag mine in Poland are presented. Thucholite, which forms spherical or granular clusters, appears scattered in the T1 dolomitic shale at the oxic-anoxic boundary occurring within the same shale member. The composition of thucholite concretions and the T1 shale differs by a higher content of U- and REE-enriched mineral phases within the thucholite concretions compared to the T1 shale, suggesting a different mineralising history. The differences also comprise higher Ntot, Ctot, Htot, Stot contents and higher C/N, C/S ratios in thucholite than in the T1 shale. The hydrocarbon composition of the thucholite and the surrounding T1 shale also varies. Both are dominated by polycyclic aromatic compounds and their phenyl derivatives. However, higher abundances of unsubstituted polycyclic aromatic hydrocarbons in the thucholite are indicative of its pyrogenic origin. Pyrolytic compounds such as benz[a]anthracene or benzo[a]pyrene are more typical of the thucholite than the T1 shale. Microscopic observations of the thucholite and its molecular composition suggest that it represents well-rounded small charcoal fragments. These charcoals were formed during low-temperature combustion, as confirmed by semifusinite reflectance values, indicating surface fire temperatures of about 400 °C, and the absence of the high-temperature pyrogenic polycyclic aromatic hydrocarbons. Charred detrital particles, likely the main source of insoluble organic matter in the thucholite, migrated to the sedimentary basin in the form of spherical carbonaceous particulates, which adsorbed uranium and REE in particular, which would further explain their different contents and sorption properties in the depositional environment. Finally, the difference in mineral content between thucholite and the T1 shale could also have been caused by microbes, which might have formed biofilms on mineral particles, and caused a change in the original mineral composition.

МОДИФИЦИРОВАНИЕ СВОЙСТВ ГИДРОТЕХНИЧЕСКИХ БЕТОНОВ ДОБАВКАМИ НА ОСНОВЕ ВЫСОКОМОЛЕКУЛЯРНЫХ СОЕДИНЕНИЙ

Ensuring high water resistance, frost resistance and corrosion resistance of hydraulic structures is achieved by creating concrete with a dense structure that can absorb aggressive influences. This is possible by modifying the structure of concrete with polymer additives of new generation. The introduction of polymer additives has a plasticizing effect and contributes to the preservation of technological properties of the concrete mixture, modifies the pore structure of concrete and influences the formation of cement stone strength. The paper presents the results of research on the effect of polymer additive based on polyvinylpyrrolidone on the basic properties of Portland cement binder. It was found that the compressive strength at the age of 2 days increases by 7% at the content of polymer additive in the amount of 0.8%. Also, in-troduction of polymer additive increases the compressive strength at the age of 28 days at its content of 0.6 and 0.8% by 22 and 27%, respectively. The effect of polymer modifier on the formation of the initial structure, manifested in the increase in the time of the beginning and accel-eration of the end of setting has been established. The kinetics of heat release of cement dough in the presence of polymeric modifier in the amount of 0.6 % has been studied. The data on the phase composition of cement stone in the presence of polymer modifier are given. It is established by means of electron microscopic analysis that the introduction of polymeric admixture promotes modification of cement stone microstructure with formation of more dense homogeneous structure. The given research results are taken into account in the development of concrete compositions with a set of specified properties required for the construction of hydraulic structures.