The developed technology of producing cements with biocidal properties and the results of investigating the physico-mechanical properties of the developed cements, cement pastes, and hardened composites are given. Data on the biostability of composites modified with sodium sulfate, sodium fluoride, and polyhexamethylene stearate are presented. Recommended biocidal binder compositions for manufacturing concretes and other cement composites are given.

Development of Biocidal Cements for Buildings and Structures with Biologically Active Environments

In recent years, both Russian and foreign researchers have paid considerable attention to the problem of ensuring the reliability of building structures at all stages of their erection and operation, reconstruction, repair and reorganization. This is due to the growing need to ensure reliable operation of unique, expensive, historically significant structures, which dismantling and replacement are much more expensive than repair or it is impossible generally. Damage to reinforced concrete structures, as a rule, is associated with corrosion, overloading of individual elements and improper operation, design and production errors. In this article, the process of examining the reinforced concrete bearing structure of the building overlap for the possibility of its reconstruction and reorganization is considered in detail, as well as the design calculation based on computer modelling in the LIRA-CAD program.

https://iopscience.iop.org/article/10.1088/1757-899X/463/4/042009/pdf

The Reliability of Building Structures Against Power and Environmental Degradation Effects

The construction industry has experienced the hugest number of changes during all century's history. Today in construction there is a huge set of scientific completions and innovative solutions that many times increase quality of works and process reliability of construction in general. This publication is devoted to an innovative element for strengthening building constructions and elements - to high-strength composite materials. Due to inevitable exhaustion of natural resources and increase in energy cost in the world the process of composite materials production in industrial is becoming more relevant, important and popular, such as fibreglass, basaltplastic, carbonoplastic. These composite materials possess sufficient characteristics on reliability, durability, profitability and that is the most important - environmental friendliness in comparison with the metal reinforcing elements. It is important that source replenishment of raw materials in modern production is possible due to processing of secondary raw materials and technogenic waste. Experience of using composite materials during strengthening building constructions, the comparative analysis from the point of ecology production and using materials, advantages of composite materials is reflected in this publication. The purpose of this publication is to show validity of using composite materials for strengthening building constructions from the point of view of reliability, profitability and also environmental friendliness in comparison with other reinforcing elements.

https://iopscience.iop.org/article/10.1088/1757-899X/365/3/032053/pdf

Technical aspects of using composite materials for strengthening constructions

Properties of new reinforcing element — composite reinforcement, are considered. Feasibility study of using this material for modernization of buildings, namely for vertical extension with additional storey, is carried out. Comparative analysis of performance is conducted for metal and composite reinforcement, as well as calculations are performed which results will be used for determination of advantages and disadvantages of this innovative reinforcing method. An important factor for development of projects of building vertical extension after quite a long operation period is a proper selection of construction materials and strength analysis considering the structures to be erected. Calculation of a floor slab erected with using composite fiberglass reinforcement is represented. Results obtained in the calculation and the analysis of the data prove high efficiency of this reinforcing method through the decrease of loads on lower storeys of the building, economic feasibility and other factors.

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Application of composite reinforcement for modernization of buildings and structures

Reliability and stability of transport facilities during their maintenance can be ensured by the application of the engineering and geodetic monitoring systems for deformation processes in structures supervision that allows avoiding emergencies. Nowadays, automatic engineering devices are successfully used in order to produce high-precision spatial measurements. Further development of deformation monitoring systems requires the development of software tools for deep analysis of structures based on data. The article considers the methodology and software for deformation monitoring of road transport structures and facilities using geodetic methods during construction, maintenance and reconstruction these structures in order to evaluate their technical availability and to prevent negative impacts on surrounding buildings and structures. In addition, it is reviewed the world’s researches on this subject, as well as practical examples of the application this methods.

Deformation Monitoring of Road Transport Structures and Facilities Using Engineering and Geodetic Techniques

In this paper, we consider a method of increasing biological resistance and biological durability of buildings and constructions that are subject to destruction from the impact of microorganisms activity. This article presents the results of studies of innovative materials in the field of bioresistant building materials. Powders of milled quartz sand and limestone were the fillers for the composites. Limestone used for the experiments is from the Chechnya depostits. We have implemented optimization for the cement composites compositions using the methods of mathematical experiment design. We derived the dependences describing how the bioresistance coefficient, the elastic modulus and the water demand depend on the granulometric composition after 3 and 9 months of aging in the environment of filamentous fungi. We have found that the multifractional compositions have a higher bioresistance coefficient. We determined the fungal resist compositions.

Biological Resistance of Cement Composites Filled with Limestone Powders

The article considers innovative materials for construction. Using mathematical planning methods, we studied how the quantitative composition, the biocidal additive and gypsum content influence on the compressive and flexural strength and density of the composites. We found that the more gypsum in a composition the higher compressive and flexural strength of a specimen. So, with the greatest degree of compositions filling (fly ash – 20 mass fractions, gypsum – 11.2 mass fractions) maximum compressive strength is 72.5 MPa. We determined when the fly ash content rises up to 20 mass fractions per 100 mass fractions of clinker, flexural strength rises too and specimen density decreases. The developed compositions of biocidal cements recommended for use in the manufacture of materials, products and structures for buildings and constructions, operating in aggressive environments.

Physical and Mechanical Properties of the Cement Stone Based on Biocidal Portland Cement with Active Mineral Additive

Type 2 diabetes mellitus (T2DM) is a serious medical and social problem leading to early disability of patients and high mortality from cardiovascular complications. The development of cardiovascular events is associated not only with the degree of coronary artery stenosis, but also with the structure of the atherosclerotic plaque. Aim. This study aimed to characterize structure and composition of coronary artery atherosclerotic plaque in target lesion of T2DM patients and patients without diabetes using intravascular ultrasound (IVUS) and IVUS with virtual histology (IVUS-VH). Materials and methods. We observed 25 patients with coronary artery disease (CAD) with T2DM and without T2DM, which admitted to Endocrinology Research Centre to perform percutaneous coronary intervention (PCI). Patients with CAD and T2DM were included at group 1 and patients with CAD and without T2DM were included at group 2. IVUS and IVUS-VH assessment of target lesion were performed prior to stent implantation. We observed 24 plaques at group 1 and 10 plaques at group 2. Results. In grey - scale IVUS 2D analysis there were no differences in mean cross - sectional area of the vessel (12.5 [10.4; 15.8] mm2 vs. 13.5 [12,7; 16.5] mm2; p=0.223, respectively) and lumen area (3.71 [2.5; 4.5] mm2 vs. 3.2 [2.7; 3.8] mm2; p=0.589, respectively). Plaque burden were higher in patients without T2DM (71.6 [65.5; 75.7] % vs. 77.6 [74.4; 80.4] %; p=0.008, respectively). IVUS-VH analysis showed that percent of necrotic core and dense calcium areas were significantly higher in the T2DM group (31.3 [25.3; 36.5] % vs. 21.65 [14.3; 27.8] %; p=0.01 and 4.7 [2.3; 7.8] % vs. 2.45 [1.2; 4.05] %; p=0.046, respectively). Percent of the fibrotic tissue were higher in non-T2DM group (55.35 [49.7; 63.6] % vs 67.7 [61.8; 76.5] %; p=0.004, respectively). There were no differences in percent of lipidic tissue in both groups. Conclusions. IVUS-VH assessment of coronary artery atherosclerotic plaques showed greater amount of necrotic core and dense calcium in patients with T2DM compared to patients without diabetes.

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Intravascular ultrasound with virtual histology in assessment of atherosclerotic plaque composition in patients with coronary artery disease and type 2 diabetes mellitus

Olga Smirnova

Papers

Biological Resistance of Cement Composites Filled with Limestone Powders

Physical and Mechanical Properties of the Cement Stone Based on Biocidal Portland Cement with Active Mineral Additive

Intravascular ultrasound with virtual histology in assessment of atherosclerotic plaque composition in patients with coronary artery disease and type 2 diabetes mellitus