scholarly journals PREPARATORY STAGE FOR MONITORING THE LOAD-BEARING STRUCTURES OF THE OPERATED SUBWAY STATION

2017 ◽  
Vol 2 (49) ◽  
pp. 116-125
Author(s):  
G. P. Pastushkov ◽  
M. A. Kisel
Keyword(s):  
Subway Station ◽  
Construction Work ◽  
State Monitoring ◽  
Safe Operation ◽  
Design Data ◽  
Load Bearing ◽  
Load Carrying ◽  
Station Base ◽  
Preparatory Stage ◽  
Modern Technologies

Modern technologies for the construction of a subway underground allow reconstruction of operated stations without stopping the movement of trains and subway  disruptions. However, this problem is quite complicated, because at the device of transitive tunnels it is possible to violate the stress-strain state of the main load-bearing structures and ground of the station base, track upper-structure drawdown appearance that is impermissible for the safe operation of the subway. The article presents the results of the preparatory stage of theMinsk subway station main load-carrying structures state monitoring, as well as the results of spatial calculations based on design data, considering the stage of transition tunnel construction work from the first to the third branches.

CALCULATION OF THE CHAIN DRIVE OF A MECHANIZED CHAMBER-CHAIN DRYING PLANT FOR DRYING MELON FRUITS

2021 ◽  
Vol 4 (1) ◽  
pp. 29-35
Author(s):  
Nafisa Saidho’jaeva ◽  
Keyword(s):  
Heat Exchanger ◽  
Chain Drive ◽  
Utility Model ◽  
Load Bearing ◽  
Air Heater ◽  
Load Carrying ◽  
Chain Transmission ◽  
A Chain ◽  
Chain Conveyor

The article deals with the calculation of the drive and chain transmission of the newly created mechanized drying plant for drying melon slices. The essence of the utility model: the machine contains a horizontal tunnel chamber, inside which is mounted a chain conveyor with driving and driven sprockets, load-carrying elements, the IR emitters with reflectors on top of the camera mounted electric air heater, fan, an annular heat exchanger equipped with inlet and outlet nozzles of the drying agent. On the branches of the conveyor chain, lodgments with folding clamps are mounted, on which load-bearing elements are fixed, which are used as wooden poles. The calculation of the drive and chain transmission of the drying plant conveyor was carried out according to the existing method according to the scheme shown in the figure. Thus, the main parameters of the drive and chain transmission parts of the mechanized chamber-chain drying plant for drying melon fruits were determined by calculation

scholarly journals CONTROL OF ACTIONS OF STEEL TANK IN WORKING

2018 ◽  
Vol 22 (4) ◽  
pp. 66-74 ◽  
Author(s):  
A. A. Vasilkin
Keyword(s):  
Strain State ◽  
Low Cycle Fatigue ◽  
Operating Conditions ◽  
Maximum Effect ◽  
Safe Operation ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
Steel Tank ◽  
Steel Tanks

In steel tanks made by the method of rolling, defects of a geometric shape often occur in the area of the welded welded joint of the wall. Subsequently, in these areas, as a result of low cycle fatigue, an unacceptable defect appears in the form of a crack, which makes it necessary to remove the reservoir from operation and carry out a set of measures for its repair. To determine the terms of safe operation of vertical steel tanks with geometric defects, it is proposed to use the methodology control of the actions of structures of load-bearing structures, one of the directions of which is the regulation of the stress-strain state of steel structures. To implement the possibility of regulating construction, it is necessary to identify such parameters, the change of which will give the maximum effect in achieving the set goals. As the indicated parameters, the design characteristics (material properties, design scheme, geometric characteristics) and factors of external influences (load, operating conditions) can act. To regulate the stress-strain state design of vertical steel tanks, the following regulators are proposed: product loading height, wall deflection arrow and permissible number of tank loading cycles. By numerical calculation of the VAT of the vertical steel tank design with geometric defects, the necessary values and values of the stress state are determined. Further, using known analytical dependencies from the field of fracture mechanics, it is possible to determine the permissible number of loading cycles of the reservoir before the appearance of a crack-like defect. The application of the methodology control of the actions of structures load-bearing structures, by means of a certain change in the established control parameters, allows increasing the number of loading cycles of the reservoir, thereby increasing the period of safe operation of the defective reservoir and thereby increasing the economic efficiency of the tank farm.

Parametric Study on Compression Deformation Behavior of Conformal Load-Bearing Smart Skin Antenna Structure

2004 ◽  
Vol 261-263 ◽  
pp. 663-668 ◽  
Author(s):  
Kwang Joon Yoon ◽  
Young Suk Kim ◽  
Young Bae Kim ◽  
J.D. Lee ◽  
Hyun Chul Park ◽  
...  
Keyword(s):  
Parametric Study ◽  
Compressive Load ◽  
Element Model ◽  
Design Data ◽  
Antenna Structure ◽  
Load Bearing ◽  
Shear Moduli ◽  
Design Variables ◽  
Compressive Loads ◽  
Smart Skin

In this paper, a simple conformal load-bearing antenna structure smart skin with a multi-layer sandwich structure composed of carbon/epoxy, glass/epoxy, and a dielectric polymer was designed and fabricated. The mechanical properties of each material in the designed smart skin were obtained from experiments. Tests and analyses were conducted to study the behavior of the smart skin under compressive loads. The designed smart skin failed due to buckling before compression failure. The stresses of each layer and the first failed layer of the smart skin were predicted using MSC/NASTRAN. The finite element model was verified by comparing the numerical results from geometrical linear/nonlinear analyses with the measured data. The numerically predicted structural behavior of the smart skin agreed well with the experimental data. The results showed that the carbon/epoxy layer took charge of most of the compressive load, and the first failure occurred in the dielectric layer while the other layers remained safe. A numerical model was used to obtain design data from the parametric study. The effect of changing the design variables on the buckling and compressive behavior of the smart skin was also investigated. As a result, it was confirmed that the transverse shear moduli of the honeycomb core had a serious impact on the buckling load of the smart skin when the shear deformation was considerable.

scholarly journals Influence of Load-bearing Structure on Size of Bonded Facade Cladding

2018 ◽  
Vol 163 ◽  
pp. 08003
Author(s):  
Pavel Liška ◽  
Barbora Nečasová ◽  
Jiří Šlanhof
Keyword(s):  
Aluminium Alloy ◽  
Bonded Joints ◽  
Test Results ◽  
Load Bearing ◽  
Moisture Expansion ◽  
Cladding Panels ◽  
People First ◽  
Materials Used ◽  
Bearing Structure ◽  
Modern Technologies

Architecture has been an integral part of our lives ever since people first existed. Structures are required by both investors and society to have what is considered a highly modern appearance while maintaining elements of a long service life. To meet such requirements, it is necessary to use modern technologies and materials. Bonded joints represent one of the options. Unlike with mechanical joints, it is possible to use bonded joints to anchor large format cladding panels to bearing substructures of various shapes and sizes. The design is simple, but very technically demanding to implement. One of the factors which have an impact on both the design and its implementation is the bearing substructure itself. As part of a research project, a load bearing substructure made from wood and aluminium alloy was tested. The test results prove that the mechanical properties of the materials used, especially their thermal and moisture expansion, directly influence the size of the cladding. In the case of a bearing substructure made from wood, the cladding may be larger by several percentage points than in the case of a bearing substructure made from aluminium alloy.

Hydrodynamic Lubrication of Finite Slider Bearings: Effect of One Dimensional Film Shape, and Their Computer Aided Optimum Designs

1983 ◽  
Vol 105 (1) ◽  
pp. 48-63 ◽  
Author(s):  
C. Bagci ◽  
A. P. Singh
Keyword(s):  
Numerical Solution ◽  
Carrying Capacity ◽  
Reynolds Equation ◽  
Hydrodynamic Lubrication ◽  
Load Carrying Capacity ◽  
Slider Bearing ◽  
Design Data ◽  
Slider Bearings ◽  
Load Carrying ◽  
Computer Aided

The effect of the film shape on the load carrying capacity of a hydrodynamically lubricated bearing has not been considered an important factor in the past. Flat-faced tapered bearing and the Raileigh’s step bearing of constant film thickness have been the primary forms of film shapes for slider bearing studies and design data developments. This article, by the computer aided numerical solution of the Reynolds equation for two dimensional incompressible lubricant flow, investigates hydrodynamically lubricated slider bearings having different film shapes and studies the effect of the film shape on the performance characteristics of finite bearings; and it shows that optimized bearing with film shapes having descending slope toward the trailing edge of the bearing has considerably higher load carrying capacity than the optimized flat-faced tapered bearing of the same properties. For example the truncated cycloidal film shape yields 26.3 percent higher load carrying capacity for Lz/Lx = 1 size ratio, and 44 percent higher for Lz/Lx = 1/2. The article then presents charts for the optimum designs of finite slider bearings having tapered, exponential, catenoidal, polynomial, and truncated-cycloidal film shapes, and illustrates their use in numerical bearing design examples. These charts also furnish information on flow rate, side leakage, temperature rise, coefficient of friction, and friction power loss in optimum bearings. Appended to the article are analytical solutions for infinitely wide bearings with optimum bearing characteristics. The computer aided numerical solution of the Reynolds equation in most general form is presented by which finite or infinitely wide hydrodynamically or hydrostatically lubricated bearings, externally pressurized or not, can be studied. A digital computer program is made available.

scholarly journals Influence of Ferrofluid Lubrication on Longitudinally Rough Truncated Conical Plates with Slip Velocity

2019 ◽  
Vol 7 (2) ◽  
pp. 93-101
Author(s):  
M M Munshi ◽  
A R Patel ◽  
G M Deheri
Keyword(s):  
Surface Roughness ◽  
Bearing Capacity ◽  
Slip Velocity ◽  
Performance Enhancement ◽  
Positive Impact ◽  
Squeeze Film ◽  
Bottom Plate ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Load Carrying

The study focuses on analyzing the effect of slip velocity in the case of a Ferrofluid squeeze film when the surface of truncated cone-shaped plates has a longitudinal roughness. Each oblique to the bottom plate was utilized by the external magnetic field. The bearing surface has a roughness that is designed with the help of a random stochastic variable having a nonzero mean, skewness and variance. The load carrying ability of a bearing system’s surface is determined by calculating the dispersal of pressure in the system, which is calculated by using the associated stochastically average Reynolds’ equation. The graphs obtained from the study shows that there is a correlation between the longitudinal surface roughness and the bearing system performance. The magnetic fluid lubrication has a positive impact on a system’s bearing capacity. However, the load bearing capacity declines as a result of the effect of slip. A high negative skewness of the surface roughness also has a positive impact on a bearing’s load carrying capacity. One interesting finding shows that contrasting to the results of transverse roughness, standard deviation positively impacts the load bearing capacity. This investigation suggests despite the im-portance of aspect ratio and semi vertical angle is significant for performance enhancement, it is also essential to maintain the slip at the lowest level.

scholarly journals FLEXURAL LOAD AND DEFLECTION BEHAVIOR OF STRUCTURAL BAMBOO FILLED WITH CEMENT MORTAR

2021 ◽  
Vol 83 (4) ◽  
pp. 31-39
Author(s):  
Gathot Heri Sudibyo ◽  
Nor Intang Setyo Hermanto ◽  
Hsuan-Teh Hu ◽  
Yanuar Haryanto ◽  
Laurencius Nugroho ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Carrying Capacity ◽  
Cement Mortar ◽  
Natural Material ◽  
Load Carrying Capacity ◽  
Structural Elements ◽  
Load Bearing ◽  
Four Point Bending ◽  
Bamboo Nodes ◽  
Load Carrying

Bamboo has been significantly and rapidly used to build temporal and permanent structures since time immemorial. However, this renewable natural material has a low bearing capacity, limiting its application to structures under light loads. Therefore, this research was carried out to determine an innovative scheme capable of enhancing bamboo's load-bearing by filling the cavity with cement mortar. Furthermore, a study was carried out to experiment flexural load carrying capacity and the deflection of mortar-filled structural bamboo by considering the diameter and node parameters. A total of 12 specimens were examined using a four-point bending protocol. The result showed the ultimate flexural load carrying capacity of mortar-filled bamboo specimens are higher than those of the conventional bamboo specimens. Specifically, mortar filled bamboo specimen with a diameter of 70 mm was significantly better, 41.10 and 47.06%, as compared than the conventional bamboo in terms of its flexural load carrying capacity for specimen without and with nodes, respectively. Increases in flexural load carrying capacity were also observed for the mortar-filled bamboo specimens having 80 and 90 mm diameter and these observed increases were recorded as 104.55 and 112.00%, and 48.72 and 60.74%, respectively for specimen without and with nodes. Furthermore, the deflection of mortar-filled bamboo elements are substantially greater than those of conventional. Finally, the advantages of the bamboo diameter and bamboo nodes on the flexural load carrying capacity indicated that these essential findings need to be carefully considered in designing structural elements for both mortar-filled and conventional bamboos.

Effect of Filler Materials on the Performance of Conformal Load-Bearing Spiral Antennas

2012 ◽  
Author(s):  
Ali Daliri ◽  
Sabu John ◽  
Chun H. Wang ◽  
Amir Galehdar ◽  
Wayne S. T. Rowe ◽  
...  
Keyword(s):  
Aerodynamic Drag ◽  
Filler Materials ◽  
Stress Concentrations ◽  
Element Analysis ◽  
Spiral Antennas ◽  
Antenna Structure ◽  
Load Bearing ◽  
Structural Reinforcement ◽  
Load Carrying ◽  
Promising Solution

The slots in spiral antennas induce stress concentrations and hence may adversely affect the load-carrying capacity of the structural antenna. To minimise the detrimental effect of the slots, appropriate fillers are required to provide structural reinforcement without compromising the radar performance of the antenna. This paper presents an investigation of the effects of electrical and mechanical properties of potential filler materials on the performance of slot spiral antennas. Finite element analysis is carried out for a slot spiral that is designed to work in the C-Band range of frequencies (4–8 GHz). Computational simulations performed using commercial software packages ANSYS® and HFSS® show that by using commercially available filler materials the stress concentration factor of the spiral slot can be reduced by 20%. The results from this research enhance the previously introduced advantages of this type of conformal load-bearing antenna structure (CLAS). This CLAS concept provides a promising solution of replacing conventional externally mounted antennas, thus reducing aircraft weight and aerodynamic drag.

scholarly journals Strengthening the existing connection of steel beams with a column

2020 ◽  
Vol 313 ◽  
pp. 00032
Author(s):  
Przemysław Palacz ◽  
Izabela Major
Keyword(s):  
Bearing Capacity ◽  
Vertical Plane ◽  
Steel Beams ◽  
Safe Operation ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Allowable Stresses ◽  
Hot Rolled ◽  
Hot Rolled Steel ◽  
Made In

The paper presents a solution that includes strengthening the connection of a support column with beams from both sides, placed in a vertical plane together with the pole. All the bar elements connected in the analyzed node were made of hot-rolled steel I-sections. Due to the need to increase the load on the joined beams to the pole, load-bearing capacity of the primary connection is lost, which necessitates the reinforcement of the existing connection. The analysis carried out in this paper shown exceeding the allowable stresses in the column web at the place of joining the beams. The calculations made in this paper showed the possibilities of restoring the safe operation of the connection node in question, by introducing elements increasing its load-bearing capacity. In addition to analytical calculations, numerical analysis was also performed using the ADINA program.

Investigations into the Fat Pads of the Sole of the Foot: Heel Pressure Studies

Foot & Ankle ◽  
1992 ◽  
Vol 13 (5) ◽  
pp. 227-232 ◽  
Author(s):  
Melvin H. Jahss ◽  
Frederick Kummer ◽  
James D. Michelson
Keyword(s):  
Clinical Symptoms ◽  
Fat Pad ◽  
Large Area ◽  
Total Load ◽  
Anatomic Structure ◽  
Load Bearing ◽  
Heel Pad ◽  
Load Carrying ◽  
Fat Pads ◽  
Broad Region

The fat pads of the heel have a structure that is optimized for load bearing. In various diseases and aging, the load-carrying ability of the heel pad is clinically impaired. The loading pattern was examined in subjects having normal heel pads and those with atrophic heel pads, both with and without clinical symptoms. Normal heel pads showed a broad region of high pressure, which accounted for a high percentage of the total load transmission. In contrast, the atrophic heels showed a high but narrow peak pressure. However, most of the load was transmitted over a large area of low pressure. There was no difference between symptomatic and asymptomatic heels. The mechanical behavior of the fat pad is discussed with particular reference to the anatomic structure of the pads. Pad thickness and septal integrity are both important to the mechanical characteristics of the fat pad. The load-bearing patterns observed are discussed in terms of the mechanical components influencing fat pad resilience. These results have direct relevance to understanding the pathophysiology of heel pain secondary to degeneration of the fat pad.

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