scholarly journals The Technology for Manufacturing HighStrength Pipe-Concrete Bearing Elements to Increase the Stability of Underground Structures

2019 ◽  
Vol 105 ◽  
pp. 01057
Author(s):  
Andrey Uglianitsa ◽  
Youry Pokatilov

It is proposed to use high bearing small-size pipe-concrete units in the construction of underground geotechnical structures instead of large-sized reinforced concrete units (support blocks, pylons, columns, etc.). The analysis of the methods of manufacturing pipe-concrete units, their advantages and disadvantages is conducted. The process flowchart for manufacturing pipe-concrete units with barothermal pre-stressing of a concrete mixture in a steel pipe was developed to ensure the collaboration of a steel pipe and a concrete core and increase its strength. Experimental research in barothermal treatment of a concrete mixture in a steel pipe was performed using the laboratory model of a pipe-concrete unit, which showed the efficiency of the proposed technological scheme for the production of pipe-concrete units. The lines for further research in the development of a method for determining the optimal parameters of the technological scheme for manufacturing pipe-concrete units with barothermal pre-stressing of a concrete mix are planned.

2020 ◽  
Vol 4 (141) ◽  
pp. 114-122
Author(s):  
DAR’YA LEBEDEVA ◽  
◽  
ANNA KARPUNICHEVA

Large forces and significant thermal effects are created on the rolls when rolling sheets. The higher the stability of the rolls, the less downtime during their rerolling and higher productivity. (Research purpose) The research purpose is in analyzing the ways of restoring rolls and choose the most appropriate method for restoring these parts. (Materials and methods) The article presents the analysis of the scientific and technical literature on the topic of rolling production, methods for restoring large-sized machine parts of machine-building and metallurgical industries that work in difficult conditions and are subject to a high degree of wear. Authors try to solve the problem by means of comparative and logical analysis based on theoretical and empirical methods of scientific research. (Results and discussion) The article presents two groups of methods for restoring rolled rolls: banding and surfacing the working layer of the roll. Authors have analyzed each method in terms of technology, equipment, and feasibility. The article presents the advantages and disadvantages of the methods under consideration. (Conclusions) The most acceptable way to restore parts with a high degree of wear is surfacing. It is most efficient to apply submerged surfacing using an additional hot additive. Such surfacing, despite some complication of the equipment design, allows to deposit the metal on the roll with low heat input and in most cases in one pass. Surfacing using an additional hot additive allows to increase the productivity of the process by up to 250 percent while reducing the penetration depth by 2-3 times and saving energy by up to 40 percent.


2019 ◽  
Vol 952 (10) ◽  
pp. 47-54
Author(s):  
A.V. Komissarov ◽  
A.V. Remizov ◽  
M.M. Shlyakhova ◽  
K.K. Yambaev

The authors consider hand-held laser scanners, as a new photogrammetric tool for obtaining three-dimensional models of objects. The principle of their work and the newest optical systems based on various sensors measuring the depth of space are described in detail. The method of simultaneous navigation and mapping (SLAM) used for combining single scans into point cloud is outlined. The formulated tasks and methods for performing studies of the DotProduct (USA) hand-held laser scanner DPI?8X based on a test site survey are presented. The accuracy requirements for determining the coordinates of polygon points are given. The essence of the performed experimental research of the DPI?8X scanner is described, including scanning of a test object at various scanner distances, shooting a test polygon from various scanner positions and building point cloud, repeatedly shooting the same area of the polygon to check the stability of the scanner. The data on the assessment of accuracy and analysis of research results are given. Fields of applying hand-held laser scanners, their advantages and disadvantages are identified.


Author(s):  
Farshad BahooToroody ◽  
Saeed Khalaj ◽  
Leonardo Leoni ◽  
Filippo De Carlo ◽  
Gianpaolo Di Bona ◽  
...  

Geosynthetics are extensively utilized to improve the stability of geotechnical structures and slopes in urban areas. Among all existing geosynthetics, geotextiles are widely used to reinforce unstable slopes due to their capabilities in facilitating reinforcement and drainage. To reduce settlement and increase the bearing capacity and slope stability, the classical use of geotextiles in embankments has been suggested. However, several catastrophic events have been reported, including failures in slopes in the absence of geotextiles. Many researchers have studied the stability of geotextile-reinforced slopes (GRSs) by employing different methods (analytical models, numerical simulation, etc.). The presence of source-to-source uncertainty in the gathered data increases the complexity of evaluating the failure risk in GRSs since the uncertainty varies among them. Consequently, developing a sound methodology is necessary to alleviate the risk complexity. Our study sought to develop an advanced risk-based maintenance (RBM) methodology for prioritizing maintenance operations by addressing fluctuations that accompany event data. For this purpose, a hierarchical Bayesian approach (HBA) was applied to estimate the failure probabilities of GRSs. Using Markov chain Monte Carlo simulations of likelihood function and prior distribution, the HBA can incorporate the aforementioned uncertainties. The proposed method can be exploited by urban designers, asset managers, and policymakers to predict the mean time to failures, thus directly avoiding unnecessary maintenance and safety consequences. To demonstrate the application of the proposed methodology, the performance of nine reinforced slopes was considered. The results indicate that the average failure probability of the system in an hour is 2.8×10−5 during its lifespan, which shows that the proposed evaluation method is more realistic than the traditional methods.


2011 ◽  
Vol 368-373 ◽  
pp. 2804-2807
Author(s):  
Bing Zhang ◽  
Xiao Mou Wang

A frequently used technique for improving the performance of geotechnical structures consists in incorporating into the backfill soil, during the construction process, regularly spaced thin reinforcing inclusions, called geotextile, geomembranes or geogrids. The stability of embankment, stabilized by reinforcing membranes, is investigated by means of a multiphase model developed in the framework of the yield design approach. By means of the kinematic approach, leading to upper bound estimates for the stability factor of the structure.


2021 ◽  
Vol 14 (1) ◽  
pp. 10-16
Author(s):  
Aleksandr Kozyukov ◽  
Vladimir Zolnikov ◽  
Svetlana Evdokimova ◽  
Oleg Kvasov ◽  
Konstantin Yakovlev ◽  
...  

The article discusses algorithmic methods for ensuring the fault tolerance of the electronic component base (ECB). The protection methods used in regular and irregular structures are described. The essence of Hamming code algorithms, composite code, error correction and detection codes is revealed. The advantages and disadvantages of using arithmetic residual code, the method of redundancy at the level of program code fragments, are shown.


Author(s):  
K. Al-Durgham ◽  
D. D. Lichti ◽  
I. Detchev ◽  
G. Kuntze ◽  
J. L. Ronsky

A fundamental task in photogrammetry is the temporal stability analysis of a camera/imaging-system’s calibration parameters. This is essential to validate the repeatability of the parameters’ estimation, to detect any behavioural changes in the camera/imaging system and to ensure precise photogrammetric products. Many stability analysis methods exist in the photogrammetric literature; each one has different methodological bases, and advantages and disadvantages. This paper presents a simple and rigorous stability analysis method that can be straightforwardly implemented for a single camera or an imaging system with multiple cameras. The basic collinearity model is used to capture differences between two calibration datasets, and to establish the stability analysis methodology. Geometric simulation is used as a tool to derive image and object space scenarios. Experiments were performed on real calibration datasets from a dual fluoroscopy (DF; X-ray-based) imaging system. The calibration data consisted of hundreds of images and thousands of image observations from six temporal points over a two-day period for a precise evaluation of the DF system stability. The stability of the DF system – for a single camera analysis – was found to be within a range of 0.01 to 0.66 mm in terms of 3D coordinates root-mean-square-error (RMSE), and 0.07 to 0.19 mm for dual cameras analysis. It is to the authors’ best knowledge that this work is the first to address the topic of DF stability analysis.


Author(s):  
Т. Дмитриева ◽  
T. Dmitrieva ◽  
Н. Куцына ◽  
N. Kucyna ◽  
А. Безродных ◽  
...  

The paper discusses the main aspects of soil reinforcement in road construction by adding a binder component to them. The use of this technology allows to solve the problem of high-quality raw materials shortage while improving the physicomechanical characteristics or keeping them at the same level, as well as to increase labor productivity and reduce production costs. The technogenic raw materials for the production of soil concrete were studied, the main physicomechanical characteristics and requirements that must be taken into account when selecting the composition of the soil concrete mixture were analyzed. The paper compares the physicomechanical characteristics of the road composite, reveals the advantages and disadvantages of introducing binder components of various types: cement, cement with modifier and a complex binder. It has been established that the introduction of a complex binder or cement with modifier contributes to the improvement of the physicomechanical characteristics while reducing the consumption of cement in the composition of the soil-concrete mixture compared to traditional soil-concrete with cement.


Author(s):  
Тарас Гриценко ◽  
Жанна Передера ◽  
Анна Теряева

В работе рассматривается возможность формирования в банковском секторе среды, в которой сотрудники смогут самостоятельно реализовывать цифровые инициативы для развития компании и самообучения. Обоснована необходимость её наличия. Проведен анализ соответствия поставленной проблемы российским и мировым трендам на основе изучения федеральных программ и оценок рейтинговых агентств. В результате исследования разработан бизнес-процесс реализации цифровых инициатив, про-веден конкурентный анализ его преимуществ и недостатков перед традиционным подходом к обучению. The article discusses the possibility of forming in the banking business an environment in which employees will be able to in-dependently implement digital initiatives for the development of the company and self-learning. The necessity of its presence is grounded. The analysis of compliance of the problem with the trends in Russia and the world based on the study of Federal programs and ratings agencies. To attract new staff with the necessary knowledge, banks have a number of tools - business classes, sponsorship programs, mentoring, hackathons, man-agement fights, case-championships, etc. It has been revealed that new professionals with technical skills can solve complex problems and generate products. But it’s difficult for them to dive into the banking sector, study its features and offer their own solutions to problems. It was also revealed that the company is interested in product results that are practice oriented. Com-bining product results and training is only possible by creating an environment in which they can discuss their ideas, find sup-port and implement them. As a result, a business process for the implementation of digital initiatives has been formed, a competi-tive analysis of its advantages and disadvantages over the tradi-tional approach to training has been conducted. strategies. The leading method of research is the definitions according grouping to the principles of the matrix method. It was revealed that the economic security concept is disclosed using factors freely com-bined into three groups (includes: sustainability, protection of interests, ensuring sovereignty), and the most common definitions are built using words-markers: state, security, advantage, process. One of the main study results is an algorithm for constructing the definition of the economic security concept, which allows to model and refine the definition of the concept based on the initial categories, consider-ing the economic context. The author's definition is also formulated, which reflects the interrelation of such components as the protection of interests, the impact of threats, the stability preservation, inde-pendence, ensuring development, self-adaptation and self-reproduction.


Author(s):  
A.A. Baimakhanov ◽  
◽  
Ye.N. Begaliyev ◽  

The article highlights the problematic moments associated with the fall of young children, adults, domestic and wild animals, as well as the entry of vehicles into communication collectors. Similar technical developments, their advantages and disadvantages are considered, a legal assessment of the technical purpose and the admissibility of introducing new structures into the structure of existing material objects is given. The key point of the article is the author's proposal for the implementation of the obtained utility model into the practice of servicing the system of urban underground structures.


1986 ◽  
Vol 18 (1) ◽  
pp. 19-29 ◽  
Author(s):  
I. Licskó ◽  
I. Takács

It has been established in laboratory model experiments that the removal of dissolved heavyimetals from wastewaters is rendered more difficult in the presence of colloid-stabilizing agents. This unfavourable effect can be eliminated by the addition of Mg2+ ions and the adjustment to a fairly high pH. By increasing the concentration of Mg2+ ions, the pH necessary for destroying the stability of colloidal dispersion can be lowered. These findings also apply to the combined removal of different heavy metals (Cu, Zn, Cr(III), Ni, Cd). In alkaline conditions, in the presence of ammonium salts, some heavy metals (Cu, Zn, Ni) form high stability amine complexes. A higher pH is necessary for the breakdown of these complexes and the satisfactory removal of heavy metals.


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