IMPORTANCE OF PIPELINE TRANSPORTATION, USE OF CONCRETE WEIGHTING AND INSULATION MEASURES, USED DURING PIPELINE CONSTRUCTION

It was determined that the advantages and importance of pipeline transportation are related to the priority of environmental measures, the fact that costs are within the norm, and the possibility of uninterrupted transportation regardless of the season. Of the transportation methods, special attention was paid to pipe transportation, which is considered to be the most efficient. At the design stage of the pipeline, the organization of repair work during the operation of the pipeline and the capital investment allocated for construction are referred to the criteria of optimality. Although there are many technologies for pipeline aggravation, the most common of these is aggregation with a concrete coating layer. It is known that pipes with a diameter of 530 mm and a wall thickness of 14 mm are used during pipe laying in offshore areas. For concrete treatment of these pipes, it is recommended to use 400-500 grade slag portland or putty cement, especially in the marine environment. Waterproofing is considered suitable for protecting submarine pipes from wear. For the implementation of the waterproofing layer, it is recommended to use either brizol or insulation in construction. An important factor is the provision of special insulation measures in the open part of the pipe after welding, which is explained in the article. Welding must be performed in accordance with the standard and welding materials must be licensed. There are many technologies for welding. Manual arc welding has the widest field of application. Prior to welding, there are important works that can affect the quality of work, including heating the pipe and sawing the pipe ring. The differences between the post-heated welding process of the pipe and the unheated welding process are known from production experience. During operation, the pipeline is affected by climate change and loads (various shock effects; seismic; as well as ripples if submerged; underwater currents, etc.). If the weld is as strong as the base metal, it will continue to do so. This strength can also be achieved by the absence of temperature differences during welding. Keywords: pipe, pump, concrete coating, insulation, welding.

Composite Polymer Coatings for Repair of Concrete Linings of Channels

The paper is dedicated to the results of research on composite polymer material used for concrete casings repair. Field approbation of new material was carried out on the irrigation channel test site during the repair of concrete coating deformation joints and cracks. The paper provides the obtained theoretical formulae and results of water permeability calculation in concrete casing cracks with smooth and rough walls. A design chart for determining water permeability of damages in the form of cracks of various coating width on channel concrete coatings was obtained. A universal nomogram was obtained for determining the water permeability of damage in the form of cracks of various opening widths on the concrete coverings of channels.

Theory and Applications of Green Corrosion Inhibitors

The book presents theoretical insights, characterization tools and mechanisms of green corrosion inhibitors and their industrial applications in areas such as reinforced concrete, coating, aircraft, oil and gas, acid pickling, water industry and the protection of metals and alloys used in electronic devices.

Green Corrosion Inhibitors for Technological Applications

Corrosion is an inevitable fact of day-to-day life, and however, because of its technological, economic, and aesthetic significance, it always receives much attention. Most of the corrosion inhibitors are environmentally harmful and toxic synthetic chemicals. In view of the toxicity of the inhibitors, the search for an eco-friendly and non-toxic corrosion inhibitor is of great interest. Green corrosion inhibitors are of concern because of increased awareness and improvements in regulations related to the environment because of their toxicity, restrict regular corrosion inhibitors. The extracts of natural products contain compounds having oxygen, carbon, nitrogen and sulfur. Such elements facilitate compounds to absorb on the surface of metal, forming a protective film to prevent corrosion. The main purpose of this chapter is to provide a comprehensive study of technological applications of green corrosion inhibitors in different industries, such as reinforced concrete, coating, aircraft, oil and gas, acid pickling, and water industry.

Repair technology of canal concrete lining with bitumen-polymer mastic

Purpose: development of technology for repairing canal linings concrete with bitumen-polymer mastic using one- and two-component latex emulsion to reduce water loss through defects in the concrete lining. Materials and methods: the technology of repairing the damaged canal lining concrete coating includes: preparation of the base for the protective coating; preparation of bitumen-polymer mastic for its application (manually) or spraying (mechanized) over the entire repaired area; preparation of equipment, mechanisms and necessary inventory; preparation for the use of material components (reagent (component A) and hardener (component B)) for mechanized application; the process of applying bitumen-polymer mastic to the repaired area. Results: according to the results of a scientific research, when repairing the internal junctions of the bottom and slopes of canal concrete linings, it is necessary to arrange fillets that have a triangle with sides 10–50 mm long in their cross-section. The use of fillets when joining concrete linings will avoid excessive consumption of repair material. The application of a one-component material is carried out manually using a spatula to repair minor damage and reduce losses through them, and the application of a two-component mastic will allow mechanized repair of the largest (areal) damage. Conclusions: the application of one- and two-component cold-curing bitumen-polymer mastic for repairing concrete lining of irrigation canals to various damages on their surface (cracks, shears, concrete scaling, destroyed seams, etc.) is considered. Technological operations for the repair and restoration of canal concrete linings (a technological map for the concrete surfaces repair with a mechanized polymer composite material has been developed), including five stages of work are presented.

Evaluation of the interaction of tyre tread with asphalt concrete coating depending on weather-climatic conditions

The tyre tread coupling with the road surface depends on a number of both external and internal factors. The controllability of the vehicle depends on the interaction between two materials. The article considers various tyre tread characteristics, the values of the coupling coefficients are determined for the tyre tread of M1 category vehicles during operation on different road conditions. The interaction of a new and worn tyre tread with the road surface has been assessed with vehicles driving on the asphalt concrete surface, taking into account weather conditions.

Road safety research in a safety audit

The article reviews the option of how to make the top pavement of asphalt-concrete mixture adhere reliably to the base, which is the underlying cement-concrete coating. The bitumen-latex emulsion is suggested as a binder for the two pavement layers.

Design of a High-Energy and High-Resolution detector for X-ray computed tomography

The Nuclear Measurement Laboratory (LMN) at CEA Cadarache in France is developing a high-energy tomograph reaching energies up to 21 MeV with high dose rates. It allows performing tomographies on massive objects (5 tons, 140 cm diameter) with a multimillimetric spatial resolution. For the control of absence of cracks, bubbles or defects in the concrete coating of some CEA waste drums, the laboratory needs a “high-resolution” version of this tomograph. The purpose of this study is to design an imaging detector able to provide a high spatial resolution on large objects with high dose resistance and scanning times of a few hours. To achieve this design, several steps are necessary and will be presented: – A first step consists in characterizing the current detection elements of the tomograph, such as the camera and its lens with experimental measurements. This enables to compare performance of these elements with that available on the market and to consider a replacement. – Then, the scintillator is selected according to experimental measurements on few scintillator types and a state of the art. – Next, the detector configuration is optimized to achieve the higher spatial resolution. Throughout these steps, we present the design of a highresolution detector with a spatial resolution around 300 µm for a 10%contrast.

ANALYSIS OF THE MECHANISM OF REINFORCEMENT OF THE ROAD STRUCTURE WITH A UNLOADING SECTION

The problem posed is about the mechanism for reinforcing the road structure with a slab with an unloading cut. The reasons for the appearance of transverse cracks in the upper layer of the road surface in winter have been investigated. Solvable equations are formulated, their finite element analogs are constructed. Cases of loads at different values of elastic module and plate sizes are considered. At low temperatures, the upper layers of the road try to reduce their length, however, due to their almost infinite length, they cannot do this and transverse disordered cracks appear in the upper layer, which, due to the action of transport loads and the forces of frozen water, lead to further delamination and destruction of the road structure. Therefore, the introduction into another layer of a reinforced slab made of a stiffer and more durable material that is capable of absorbing increased stresses allows the upper layer to shorten and lengthen freely and removes the arising longitudinal thermal stress. Due to the fact that this plate is located in the zone of stress concentration, these stresses become less dangerous. KEYWORDS: AUTOMOBILE ROAD, ASPHALT-CONCRETE COATING, LOADING RISK, TRACKED TRACKS, TRANSPORT LOADS, STRESS FIELD, THERMO ELASTIC STATE