Photothermal pneumatic wheel with high loadbearing capacity

Frost damage in the exterior, loadbearing, clay brick walls of two 5-storey apartment buildings could have seriously affected their loadbearing capacity if left unchecked. A coating applied to the exterior had not stopped further damage from occurring. This paper describes the work to determine the cause of the damage. The work included a condition survey, tests on the brick, and monitoring temperature and moisture levels in a section of the wall. Bricks on an easterly exposure suffered the most damage. The cause was traced to poor quality bricks combined with water infiltration mainly from rain. Remedial measures included cladding the exterior of the brickwork with an insulated siding and replacing severely damaged bricks. Key words: building, masonry, loadbearing, frost resistance, clay brick, moisture, exterior insulation.

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On the Effects of Edge Scalloping for Collapsible Spokes in a Non-Pneumatic Wheel During High Speed Rolling

Volume 13: New Developments in Simulation Methods and Software for Engineering Applications; Safety Engineering, Risk Analysis and Reliability Methods; Transportation Systems ◽

10.1115/imece2009-11342 ◽

2009 ◽

Cited By ~ 2

Author(s):

Maya Ramachandran ◽

Shashank Bezgam ◽

Lonny L. Thompson ◽

John C. Ziegert ◽

Timothy B. Rhyne ◽

...

Keyword(s):

High Speed ◽

Acoustic Noise ◽

Contact Region ◽

Element Model ◽

Design Criterion ◽

Mode Shapes ◽

Time Signal ◽

Design Strategies ◽

Pneumatic Wheel ◽

Out Of Plane

The acoustic signature produced by non-pneumatic wheels with collapsible spokes is a critical design criterion for automotive and other mobility applications. During high speed rolling, acoustic noise may be produced by the interaction of vibrating spokes with a shear deformable ring as they enter the contact region, buckle and then snap back into a state of tension. In order to identify and help understand the causes of acoustic noise for a rolling non-pneumatic wheel, a two-dimensional finite element model with geometric nonlinearity has been utilized. The model consists of a shear ring modeled as two relatively inextensible membranes with high circumferential modulus separated by a hyper-elastic material. The temporal variation in spoke length as the spoke passes through the contact zone is extracted and used as input to a three-dimensional (3-D) model of a single spoke. The 3-D spoke model is able to capture out-of-plane vibration modes of the spoke which may contribute as a source of acoustic excitation and allows for modeling of edge scalloping. Natural frequencies and mode shapes of the various spoke design strategies are computed and correlated with the frequency response of the out-of-plane spoke vibrations. Results indicate that scalloping the edges of the spoke can dramatically reduce the amplitude of vibration, but does not have a strong effect on location of frequency peaks in a FFT of the time-signal. An optimal amount of scalloping was determined which reduces maximum vibration amplitude to an asymptotic value.

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Rationale for Selecting a Method for Determining Parameters of the Contact Spot of Pneumatic Wheel Mover With Support Base

Bulletin of Science and Practice ◽

10.33619/2414-2948/43/27 ◽

2019 ◽

Vol 5 (6) ◽

pp. 212-228

Author(s):

A. Lipkan ◽

◽

A. Panasyuk ◽

R. Kashbulgayanov ◽

◽

...

Keyword(s):

Contact Spot ◽

Pneumatic Wheel

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Surface Modification of Metallic Inserts for Enhancing Adhesion at the Metal–Polymer Interface

Polymers ◽

10.3390/polym13224015 ◽

2021 ◽

Vol 13 (22) ◽

pp. 4015

Author(s):

Libor Novák ◽

Ladislav Fojtl ◽

Markéta Kadlečková ◽

Lukáš Maňas ◽

Ilona Smolková ◽

...

Keyword(s):

Critical Factor ◽

Surface Geometry ◽

Surface Textures ◽

Chemical Treatments ◽

Polymer Interface ◽

Mechanical Pretreatment ◽

Adhesion Joint ◽

Combination Of Material ◽

Loadbearing Capacity ◽

Metal Polymer

A combination of mechanical and chemical treatments was utilized to modify the surface textures of copper and duralumin inserts in order to enhance the adhesion at the metal–polymer interface and provide an adhesive joint with a high loadbearing capacity. Pretreatment of the surfaces with sandblasting was followed by etching with various chemical mixtures. The resulting surface textures were evaluated with a scanning electron microscope (SEM) and an optical confocal microscope. Surface geometry parameters (Sa, Sz, and Sdr) were measured and their relationships to the adhesion joint strength were studied. It was found that the virgin and purely mechanically treated inserts resulted in joints with poor loadbearing capacity, while a hundredfold (duralumin) and ninetyfold (copper) increase in the force to break was observed for some combinations of mechanical and chemical treatments. It was determined that the critical factor is overcoming a certain surface roughness threshold with the mechanical pretreatment to maximize the potential of the mechanical/chemical approach for the particular combination of material and etchant.

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LOADBEARING CAPACITY OF LSF WALLS UNDER FIRE EXPOSURE

MATTER International Journal of Science and Technology ◽

10.20319/mijst.2018.43.104124 ◽

2018 ◽

Vol 4 (3) ◽

pp. 104-124

Author(s):

Paulo A. G. Piloto ◽

◽

Mohamed S. Khetata ◽

Ana B. R. Gavilán ◽

◽

...

Keyword(s):

Fire Exposure ◽

Loadbearing Capacity

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Reconstructing the Load-Bearing Capacity of Deteriorated, Concrete Airfield Pavements Using Prefabricated Slabs

Research Works of Air Force Institute of Technology ◽

10.2478/afit-2018-0002 ◽

2018 ◽

Vol 41 (1) ◽

pp. 31-61

Author(s):

Mariusz Wesołowski ◽

Agata Kowalewska ◽

Bartosz Świerzewski

Keyword(s):

Bearing Capacity ◽

Laboratory Tests ◽

Field Tests ◽

Working Life ◽

Concrete Slabs ◽

Load Bearing Capacity ◽

Load Bearing ◽

Operation Period ◽

Fast Reconstruction ◽

Loadbearing Capacity

Abstract The age of currently operated concrete airfield pavements in Poland exceeds 30 years operation period many times. Such a long working life of airfield pavements forced to search for the efficient and fast technologies of their reconstruction. The article described in detail the technologies of fast reconstruction of airfield concrete slabs using prefabricated slabs. The addressed technology guarantees the reconstruction and even the improvement of the condition of loadbearing capacity of mentioned airfield slabs which was confirmed during laboratory tests, field tests and practically verified in the real operation in the International Airport Kraków-Balice.

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Mechanical Characteristic Analysis of Softness Consolidation Abrasives Pneumatic Wheel

Journal of Mechanical Engineering ◽

10.3901/jme.2014.11.170 ◽

2014 ◽

Vol 50 (11) ◽

pp. 170 ◽

Cited By ~ 1

Author(s):

Xi ZENG

Keyword(s):

Mechanical Characteristic ◽

Characteristic Analysis ◽

Pneumatic Wheel ◽

Softness Consolidation Abrasives

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Evaluation of methods for experimental and analytical determination of the contour area of the contact patch of a pneumatic tire with a support base

Traktory i sel'hozmashiny ◽

10.31992/0321-4443-2021-1-40-50 ◽

2021 ◽

Vol 1 (1) ◽

pp. 40-50

Author(s):

A.V. Lipkan' ◽

◽

A.N. Panasyuk ◽

Z.A. Godzhayev ◽

A.V. Lavrov ◽

...

Keyword(s):

Field Work ◽

Computational Method ◽

Analytical Determination ◽

Engineering Practice ◽

Tire Pressure ◽

Method Error ◽

Digital Photograph ◽

Contact Patch ◽

Pneumatic Wheel

Subject of study. The results of experiments on the estimation of the error of methods of experi-mental and calculated determination of the contour area for the ecological assessment of a mobile energy device (MED) are presented. There was used the example of modern radial tires 360 / 70R24 of Bel-89 and 18.4R34 of F-11 agricultural tractor MTZ-1025.2. in modes of non-nominal loading at nominal load on tires and changes in tire pressure within the range recommended for field work. The purpose of the study. To assess the possibility of improving the computational method for determining the contour area of the contact patch of the tire tread of a pneumatic wheel based on the mathematical model of V.L. Biederman. Materials and methods. The assessment was carried out for four ways of determining the area of the tire contact patch: 1) directly measuring the area using a digital photograph of the tire contact patch in Kompas-3D V13 software with the de-termination of the scaling and method error using a square from 100x100 mm graph paper; 2) calcu-lation by the formula of the area of an ellipse, using the length and width of the tire contact patch, measured with a tape measure directly from the obtained print; 3) by calculation, determined from the digital photograph in Kompas-3D V13 software; 4) by calculation, determined by calculation using the parameters of the universal tire characteristic (UTC). Results and discussion. As a result of the experiments, it was found that for modern radial tractor tires, the static deformation of which does not exceed 18-22%, the method of theoretical determination of the contour area of the tire contact patch using the UTC parameters can be applied with sufficient (for engineering practice) accuracy. Full convergence of the calculated and experimental contour areas of the tire contact patch can be provided by the coefficient of their ratio. Conclusions. The carried out assessment of the possibility of using methods for calculating the conditional contour area of the tire showed that these methods can be well used for a comparative assessment of the technogenic mechanical impact of propellers on the soil.

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