scholarly journals Geotechnology of restoration of culverts in complex ground conditions without their decommissioning

2019 ◽  
Vol 265 ◽  
pp. 05003
Author(s):  
Nicolay Perminov ◽  
Andrey Perminov
Keyword(s):  
Experimental Design ◽  
Technical Condition ◽  
Operating Conditions ◽  
The Body ◽  
Construction Site ◽  
Engineering Structures ◽  
Design Work ◽  
Concrete Pipes ◽  
Ground Conditions ◽  
Water Disposal

In the article, on the basis of extensive theoretical and experimental research carried out, innovative geotechnology for repair of culverts is presented, which provides an improvement in the conditions for interaction between the body of the structure and the soil massif with increasing technogenic impacts. The analysis of the technical condition of the culvert transport and engineering structures under special operating conditions is given. Factors determining their premature emergency condition and interfering with stable functioning under increasing loads and impacts have been studied. On the basis of many years of experimental and theoretical and experimental design work, geotechnology «Saturn» has been proposed, suitable for repairing all types of culverts on railroads and highways, engineering infrastructure facilities, and especially for repair and reconstruction of pipes under conditions of a constant intensive watercourse with nonstandard (atypical) constructive solutions, as well as located in hard-to-reach and difficult for the organization of the construction site sections of the route. The experience of successful application of the developed technology "Saturn" on the railroad during the repair and reconstruction of long-maintained culverts of stone and concrete pipes under the conditions of a constant intensive watercourse and at water disposal facilities during repair of deep tunnels without their decommissioning is described.

scholarly journals Geotechnical and ecological foundations of the sustainable life cycle of the long-operated unique underground structures of the water disposal system in difficult ground conditions

2019 ◽  
Vol 265 ◽  
pp. 05002
Author(s):  
Nicolay Perminov
Keyword(s):  
Life Cycle ◽  
Operational Reliability ◽  
Technical Condition ◽  
Simultaneous Increase ◽  
Underground Structures ◽  
Joint Work ◽  
Soil System ◽  
Ground Conditions ◽  
Condition Modeling ◽  
Water Disposal

Intensive development of megacities causes the need for sustainable operation of underground urban infrastructure facilities. In the special protection against man-made impact, long-operated unique underground structures of the water disposal system, which are related to facilities with an increased level of responsibility and danger, are needed. In the report, based on the experience of studying the operation of underground wastewater facilities in conditions of weak soils and intensive external static and dynamic impacts, there are proposed new methods for diagnosing their technical condition, modeling and monitoring of the joint work of the "underground structures aggregate of soil" system are implemented, forecasting and shaping conditions for its sustainable life cycle. Point and linear objects of the water canal of St. Petersburg are developed and implemented at unique (to a depth of 70 m.) geotechnology, providing simultaneous increase of bearing capacity, operational reliability and ecological safety of longoperated underground drainage facilities in difficult ground conditions with increasing man-caused impacts.

scholarly journals THE RELEVANCE OF CHANGING THE DESIGN SOLUTION COVERAGE WITHOUT STRENGTHENING EXISTING FOUNDATIONS

2019 ◽  
Vol 7 (2) ◽  
pp. 42-49
Author(s):  
Ольга Хрянина ◽  
Ol'ga Hryanina ◽  
Мария Колесникова ◽  
Maria Kolesnikova
Keyword(s):  
Raw Materials ◽  
Technical Condition ◽  
Operating Conditions ◽  
Design Solution ◽  
Building Structures ◽  
Construction Site ◽  
Satisfactory Condition ◽  
Geological Conditions ◽  
Design Values ◽  
Instrumental Methods

The authors carried out the study of raw materials and their analysis, which allowed to identify the engineering-geological conditions of the construction site and outline the program of scientific and survey works. Full-scale and instrumental examination of the technical condition of the bearing and enclosing structures of the building. It is established that the building structures during operation have not received deformations that prevent normal operating conditions and are currently in satisfactory condition. The strength of concrete Foundation organoleptic and instrumental methods, which showed compliance with the design values. Analysis of verification calculations of the base, a satisfactory condition of the building structures showed that the structural solution of the coating can be changed and performed in kind without strengthening the existing foundations.

scholarly journals Criteria Justification for Assessing the Technical Condition of Gearboxes of Mining Machines Based on Infrared Thermography

2020 ◽  
Vol 174 ◽  
pp. 03003 ◽  
Author(s):  
Evgeniy Kuzin ◽  
Boris Gerike ◽  
Vitaliy Shachmanov
Keyword(s):  
Heat Release ◽  
Theoretical Basis ◽  
Technical Condition ◽  
Operating Conditions ◽  
The Body ◽  
Mining Machine ◽  
Belt Conveyor ◽  
Actual Load ◽  
Early Failures ◽  
Complex Technical Systems

The paper presents the relevance of advanced assessment of the technical condition of complex technical systems. One of which is the gearbox of a mining machine. The main reasons for early failures of bearings are shown. The main share is occupied by problems of lubrication, incorrect installation and maintenance. The analysis of types of destruction of gears of mining machines is presented. The main share is occupied by the surface coloring of the teeth and sudden fracture of the tooth as a result of dynamic load. The theoretical basis for determining the heat release of bearings is given. The calculation of heat release is given of a shaft belt conveyor gearbox as an example, which is confirmed by thermographic studies under operating conditions. Justification of criteria for evaluating the technical condition of gearboxes of mining machines in the form of temperature anomalies recorded on the surface of the body, The actual load on the output shaft is taken into account.

scholarly journals Modeling and Sensitivity Analysis of the Forward Osmosis Process to Predict Membrane Flux Using a Novel Combination of Neural Network and Response Surface Methodology Techniques

Membranes ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 70
Author(s):  
Jasir Jawad ◽  
Alaa H. Hawari ◽  
Syed Javaid Zaidi
Keyword(s):  
Response Surface Methodology ◽  
Experimental Design ◽  
Response Surface ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Operating Conditions ◽  
Ann Model ◽  
Membrane Flux ◽  
Input Variables ◽  
Rsm Model

The forward osmosis (FO) process is an emerging technology that has been considered as an alternative to desalination due to its low energy consumption and less severe reversible fouling. Artificial neural networks (ANNs) and response surface methodology (RSM) have become popular for the modeling and optimization of membrane processes. RSM requires the data on a specific experimental design whereas ANN does not. In this work, a combined ANN-RSM approach is presented to predict and optimize the membrane flux for the FO process. The ANN model, developed based on an experimental study, is used to predict the membrane flux for the experimental design in order to create the RSM model for optimization. A Box–Behnken design (BBD) is used to develop a response surface design where the ANN model evaluates the responses. The input variables were osmotic pressure difference, feed solution (FS) velocity, draw solution (DS) velocity, FS temperature, and DS temperature. The R2 obtained for the developed ANN and RSM model are 0.98036 and 0.9408, respectively. The weights of the ANN model and the response surface plots were used to optimize and study the influence of the operating conditions on the membrane flux.

Designing CO2 Transmission Pipelines Without Crack Arrestors

2010 ◽  
Author(s):  
Graeme G. King ◽  
Satish Kumar
Keyword(s):  
Wall Thickness ◽  
Carbon Capture ◽  
Power Plants ◽  
Oil And Gas ◽  
Cost Optimization ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Design Work ◽  
Industrial Facilities ◽  
Pipeline Network

Masdar is developing several carbon capture projects from power plants, smelters, steel works, industrial facilities and oil and gas processing plants in Abu Dhabi in a phased series of projects. Captured CO2 will be transported in a new national CO2 pipeline network with a nominal capacity of 20×106 T/y to oil reservoirs where it will be injected for reservoir management and sequestration. Design of the pipeline network considered three primary factors in the selection of wall thickness and toughness, (a) steady and transient operating conditions, (b) prevention of longitudinal ductile fractures and (c) optimization of total project owning and operating costs. The paper explains how the three factors affect wall thickness and toughness. It sets out code requirements that must be satisfied when choosing wall thickness and gives details of how to calculate toughness to prevent propagation of long ductile fracture in CO2 pipelines. It then uses cost optimization to resolve contention between the different requirements and arrive at a safe and economical pipeline design. The design work selected a design pressure of 24.5 MPa, well above the critical point for CO2 and much higher than is normally seen in conventional oil and gas pipelines. Despite its high operating pressure, the proposed network will be one of the safest pipeline systems in the world today.

Investigation of the interaction of car wheels with the stand rollers during braking

2021 ◽  
Vol 13 (1) ◽  
pp. 68-77
Author(s):  
Igor Мarmut ◽  
◽  
Andriy Kashkanov ◽  
Vitaliy Kashkanov ◽  
◽  
...  
Keyword(s):  
Traffic Safety ◽  
Technical Condition ◽  
The Body ◽  
Power Model ◽  
Equilibrium Equations ◽  
Design Features ◽  
Complex Objects ◽  
Passenger Cars ◽  
Wheel Drive ◽  
Four Wheel Drive

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. As an example, the study of the braking qualities of four-wheel drive cars on an inertial roller stand is considered. Diagnosing the technical condition of cars from the point of view of traffic safety is one of the most important problems. This is especially important for systems whose technical condition affects traffic safety: especially braking systems. Foreign and domestic experience testifies to the effectiveness of instrumental control. The diagnostic equipment includes roller stands, on which you can check the braking properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. Such stands allow you to reproduce the real speed and thermal modes of the brakes (especially those equipped with ABS). To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the rollers. The studies of wheel rolling on the stand rollers have been carried out by many authors since the 80s of the last century. However, all these studies were carried out on uniaxial stands and for mono-drive vehicles. Nowadays, a large number of passenger cars have four-wheel drive. Rolling of the wheels of such cars on rollers and their interaction has practically not been studied. Therefore, a return to the study of this issue is relevant. A power model of the system of interaction between the car and the stand has been developed, taking into account the design features of the stand and the design features of the car's suspension. The power model of the system under consideration contains the equilibrium equations of the body and two bridges and the equations of motion of the rollers and wheels of the car. Based on the results of the analysis of the acting forces in the "car-stand" system, the braking moments on the wheels M and the coefficients of the use of the load q during the braking tests of a 4x4 vehicle were determined. The obtained research results allowed to improve the theory of interaction of a car wheel with the rollers of an inertial diagnostic stand.

Using Taguchi Experimental Design to Investigate Operating Variables That Significantly Affect Wear in Mud Pumps

1995 ◽  
Vol 209 (1) ◽  
pp. 29-40
Author(s):  
S H Mok ◽  
D G Gorman
Keyword(s):  
Experimental Design ◽  
Normal Load ◽  
Drilling Fluid ◽  
Operating Conditions ◽  
Taguchi Experimental Design ◽  
Drilling Mud ◽  
Test Rig ◽  
Offshore Drilling ◽  
Wear Rates ◽  
Operating Variables

Maintenance of offshore drilling mud pumps is normally based on running hours. It is generally accepted, however, that time does not provide an accurate means of scheduling maintenance, given the varying operating conditions of the reciprocating mud pumps. The energy expended at the interaction of sliding surfaces is hypothesized to be a better alternative. The effects of operating variables on wear rates are investigated. A Taguchi experimental design was used to identify those factors that significantly affect wear. Within the confines of an experimental test rig, the normal load and abrasive sand content was found to have a significant effect on the specific wear rate of nitrile rubber sliding on steel in drilling fluid.

scholarly journals Research on forest terrain roughness as a source of dynamic action on the vehicle

2017 ◽  
Vol 63 (No. 8) ◽  
pp. 363-369
Author(s):  
Mikleš Milan ◽  
Helexa Milan ◽  
Mikleš Juraj
Keyword(s):  
Correlation Function ◽  
Spectral Density ◽  
Power Spectral Density ◽  
Ground Surface ◽  
Operating Conditions ◽  
Mobile Object ◽  
Object A ◽  
Power Spectral ◽  
Gneiss Granite ◽  
Ground Conditions

The issue of terrain conditions is very complex and its description is approached from different perspectives and with different objectives. Because it consists of the gathering of basic information for a mobile object, a wheeled forestry tractor, the terrain-vehicle approach was taken as the basis. Ground conditions are part of the operating conditions of wheeled forestry tractors. Uneven ground can be regarded as a source of vibration in the vehicle – towing truck. In this respect, given the random shape of the surface roughness, the solution to vibrations leads to a terrain correlation analysis in order to obtain a correlation function and power spectral density of the ground surface. Scanning of the ground micro-profile was performed using a device for quick terrain scanning, which from the mechanical aspect consists of a towing vehicle and a measuring carriage. Correlation function and power spectral density are the evaluation based on ground micro-profile measurements and the results of calculations. Measurements of forest terrain (road) micro-profile were done in the area of Little Fatra and Little Carpathians in Slovakia. In geological terms, the measurements were done in an area with the occurrence of gneiss, granite, limestone and flysch. No measurements were performed in a sandy area.

scholarly journals Методика для трибодиагностики судовых крейцкопфных дизелей на основе имитационного моделирования

2020 ◽  
Author(s):  
A.V. Golenishev ◽  
A.V. Nadezkin ◽  
M.E. Starchenko
Keyword(s):  
Diesel Engine ◽  
Simulation Model ◽  
Technical Condition ◽  
Operating Conditions ◽  
Marine Diesel Engine ◽  
Threshold Values ◽  
Piston Group ◽  
Marine Diesel ◽  
Cylinder Piston ◽  
Wear Products

Рассматриваются подходы по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующие переход объекта диагностирования судового крейцкопфного дизеля из одного технического состояния в другое. Показано, что существующие методики не учитывают индивидуальные особенности и техническое состояние деталей цилиндропоршневой группы. Предложено для решения задачи их трибодиагностики использовать разработанную имитационную модель, позволяющую провести моделирование процесса изнашивания цилиндровой втулки и поршневых колец судового дизеля и на основании полученных расчетов определить концентрацию продуктов износа поступивших в отработанное цилиндровое масло при различной скорости изнашивания трущихся деталей. Данные о фактической концентрации продуктов износа в отработанном цилиндровом масле в дальнейшем соотносятся с результатами моделирования, что позволяет оценить техническое состояние деталей цилиндропоршневой группы двигателя. Представлены результаты моделирования по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующее переход судового дизеля из исправного в несправное техническое состояние. Даны практические рекомендации по выбору пороговых значений содержания продуктов износа в отработанном цилиндровом масле для различных типов судовых крейцкопфных дизелей и условий их эксплуатации.The article examines approaches to determine the threshold values of the concentration of wear debris in used cylinder oil that characterize the transition of a ship crosshead diesel engine unit under test from one technical condition to another. It is shown that the existing methods do not take into account the individual characteristics and technical condition of the parts of the cylinder-piston group. To solve the problem of tribodiagnostics, it is proposed to use the developed simulation model, which allows modeling the wear process of the cylinder bushing and piston rings of a marine diesel engine and, based on the obtained results, determining the concentration of wear products issued in the used cylinder oil at different wear rates of the moving parts. The data on the actual concentration of wear products in the used cylinder oil are subsequently correlated with the simulation model results, which makes it possible to evaluate the technical condition of the parts of the engine cylinder-piston group. The article presents the results of modeling of threshold values determination of the concentration of wear products in used cylinder oil, that measure the transition of a marine diesel engine from a working condition to a malfunctioning technical condition. Practical recommendations are given on choosing threshold values for the concentration of wear products in used cylinder oil for various types of marine crosshead diesel engines and their operating conditions.

scholarly journals The influence of centrial forces on crankshaft bearing lubrication is in emergency modes of the engine of the car

2021 ◽  
Vol 12 (2) ◽  
pp. 112-121
Author(s):  
Oleksandr Khrulev ◽  
◽  
Olexii Saraiev ◽  
Iryna Saraieva ◽  
◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Operating Mode ◽  
Internal Combustion ◽  
Technical Condition ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Oil Supply ◽  
Technical Expert ◽  
The Difference

The analysis of the crankshaft bearing condition of the automotive internal combustion engines in the case of insufficiency and breakage of oil supply to them is carried out. It is noted that this fault is one of the most common causes of damage to rubbing pairs in operation. At the same time, the different groups of bearings are often damaged, which cannot be explained within the framework of existing models of plain bearing lubrication. The objective of the work is to develop a mathematical model of oil supply to connecting rod bearings in emergency mode, taking into account the characteristic features of the bearing design. The model also, depending on the nature of the damage, should help to determine and explain the causes of bearing failures if they occur in different modes when operating conditions are broken. A computational model has been developed that makes it possible to assess the effect of design differences in the features of oil supply and the action of the centrifugal forces during crankshaft rotation on the oil column in the lubrication hole where oil is supplied to the conrod bearing. Calculations of the change in time of the oil supply pressure to the connecting rod bearings for the various designs of the crankshaft lubrication holes have been performed. It is shown that, depending on the operating mode of the engine and its design, the oil pressure in front of the connecting rod bearings does not disappear immediately after oil supply failure to crankshaft. Moreover, the lower the crankshaft speed is, the longer the lubrication of the conrod bearings will continue. The calculation results are confirmed by the data of the expert studies of the engine technical condition, in which the crankshaft was wedged in the damaged main bearings was found in the absence of serious damage to the connecting rod ones. It has been found that such features of the damage correspond to an rapid breakage of the oil supply to the crankshaft in the case of such operational damage as the oil pump and pressure reducing valve failure, the oil filter seal and oil pan destruction, etc. The developed model explains the difference in lubrication conditions and in the damage feature to the main and connecting rod bearings in the emergency cases of the oil supply breakage, which are observed during operation, and helps to clarify the failure causes. This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines when the operating conditions are broken.

Sign in / Sign up

Export Citation Format

Share Document