scholarly journals A.A. ILYUSHIN'S FINAL RELATION, ALTERNATIVE EQUIVALENT RELATIONS AND VERSIONS OF ITS APPROXIMATION IN PROBLEMS OF ELASTIC DEFORMATION OF PLATES AND SHELLS. PART 2: ALTERNATIVE EQUIVALENT RELATIONS OF A.A. ILYUSHIN

2020 ◽  
Vol 16 (3) ◽  
pp. 78-99
Author(s):  
Aleksandr Starov ◽  
Sergei Kalashnikov
Keyword(s):  
Plastic Deformation ◽  
Bearing Capacity ◽  
Elastic Deformation ◽  
Yield Surface ◽  
Parametric Form ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Elastoplastic Deformations ◽  
Geometric Image ◽  
Plates And Shells

The finiterelationship between the forces and moments of plates and shells in the parametric form of the theory of small elastoplastic deformations is investigated of A.A. Ilyushin, to determine the load-bearing capacity of structures from a material without hardening. A geometric image of the exact yield surface in the space of generalized stresses is obtained. In the firstpart of the article the conclusion of the finalrelation is given. In the second and third parts, by introducing other parameters, alternative equivalent dependences of the finalrelationship have been developed and variants of its approximation for application in computational practice are considered. In the fourth part, additional properties of the finalrelationship are considered, the possibility and necessity of its use in problems of plastic deformation of plates and shells is shown.

scholarly journals A.A. ILYUSHIN S FINAL RELATION, ALTERNATIVE EQUIVALENT RELATIONS AND VERSIONS OF ITS APPROXIMATION IN PROBLEMS OF PLASTIC DEFORMATION OF PLATES AND SHELLS PART 1: A.A. ILYUSHIN S FINAL RELATION

2020 ◽  
Vol 16 (1) ◽  
pp. 106-129
Author(s):  
Aleksandr Starov ◽  
Sergei Kalashnikov
Keyword(s):  
Plastic Deformation ◽  
Yield Surface ◽  
Parametric Form ◽  
Load Bearing ◽  
Elastoplastic Deformations ◽  
Geometric Image ◽  
Fourth Part ◽  
Plates And Shells

The finite relationship between the forces and moments of plates and shells in the parametric form of the theory of small elastoplastic deformations is investigated of A.A. Ilyushin, to determine the load-bearing ca­pacity of structures from a material without hardening. A geometric image of the exact yield surface in the space of generalized stresses is obtained. In the first part of the article the conclusion of the final relation is given. In the second and third parts, by introducing other parameters, alternative equivalent dependences of the final rela­tionship have been developed and variants of its approximation for application in computational practice are considered. In the fourth part, additional properties of the final relationship are considered, the possibility and necessity of its use in problems of plastic deformation of plates and shells is shown.

Traglastberechnung versteifter Platten und Schalen unter Berücksichtigung realer Schweißimperfektionen/Load-bearing capacity of Stiffened Plates and Shells Considering Realistic Weld Imperfections

Bauingenieur ◽  
2018 ◽  
Vol 93 (10) ◽  
pp. 403-411
Author(s):  
C. Stapelfeld ◽  
B. Launert ◽  
H. Pasternak ◽  
N. Doynov ◽  
V. Michailov
Keyword(s):  
Bearing Capacity ◽  
Stiffened Plates ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Finite Elemente ◽  
Plates And Shells

Imperfektionen, die bei Traglastberechnungen Berücksichtigung finden müssen, haben ihre Ursachen in Herstellungs- und Fertigungstoleranzen oder werden durch das Schweißen und den damit zumeist einhergehenden Nachbehandlungen in den Bauteilen hervorgerufen. Durch die Wärmewirkung des Schweißens entstehen sowohl sehr große Verformungen als auch signifikante Zug und Druckspannungen. Der strukturelle und geometrische Imperfektionsgrad wird somit maßgeblich von der Anzahl und der Lage der Schweißnähte sowie den Schweißparametern bestimmt. Für die Berücksichtigung in Traglastberechnungen ist ein physikalisch fundiertes Modell erforderlich, welches die Schweißimperfektionen schnell und präzise berechnet. Das gekoppelte analytisch numerische Hybridmodell erfüllt diese Kriterien. Die mathematischen Grundlagen des analytischen Modells sowie die Kopplung mit der numerischen Finite-Elemente-Berechnung werden eingangs vorgestellt und die Anwendung zur Berechnung von Verzügen an einer Schiffsektion demonstriert. Darauffolgend wird das Hybridmodell an einer eben und einer gekrümmten versteiften Platte zur Berechnung der Schweißimperfektionen angewendet. Anschließende Traglastberechnungen sowie der Vergleich mit den Ergebnissen unter der Annahme einer geometrischen Ersatzimperfektion in Form des kritischsten Eigenwerts gibt Auskunft darüber, welches Potenzial die realitätsnahe direkte Berücksichtigung von Schweißimperfektionen birgt.

Deformation Characteristics and Load-Bearing Capacity of NO.21 Coal Seam’s Mudstone Floor in Western Henan

2013 ◽  
Vol 644 ◽  
pp. 175-178
Author(s):  
Jing Ping Wei ◽  
Fan Chen ◽  
Zhi Hao Ding
Keyword(s):  
Plastic Deformation ◽  
Bearing Capacity ◽  
Peak Load ◽  
Layer By Layer ◽  
Specific Pressure ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Transition Mechanism ◽  
Failure State ◽  
Weak Plane

Through the floor specific pressure test, the floor specific pressure was obtained. The rock mass of mudstone, under the loading perpendicular to the weak plane, was in brittle-plastic failure state, and the bearing capacity of mudstone was equal to the Ⅲa grade floor. The brittle-plastic transition mechanism of the mudstone was revealed: Firstly, the more size, the more heterogeneity. The mudstone body was bigger than its rock samples, so there were more planes of weakness, which caused the macroscopic plastic deformation. Secondly, the directions of the load and the weak plane influenced the strength of the mudstone floor. During the plastic deformation, the compressive failure occurred layer by layer under the loading perpendicular to the weak planes, and the post peak load-bearing capacity of mudstone floor was decided by the layer’s strength.

Load-Bearing Capacity of Functioning Alumina Dental Endosseous Implants

1976 ◽  
Vol 55 (1) ◽  
pp. 22-29 ◽  
Author(s):  
S.H. Wolfson ◽  
G.W. Svare ◽  
D. Weber
Keyword(s):  
Plastic Deformation ◽  
Bearing Capacity ◽  
Histological Examination ◽  
Rhesus Monkeys ◽  
Maximum Load ◽  
Load Bearing Capacity ◽  
Bone Implant ◽  
Load Bearing ◽  
Endosseous Implants

Ten, solid, 99.7% Al 2O3 implants were sur'gically placed bilaterally in the mandibles of Rhesus monkeys and were then placed in function after two to four weeks. After 95 to 179 days, bone blocks were surgically removed. Load-bearing capacity of the six successful implants was determined as the maximum load that did not produce plastic deformation. The average of this value was 57.5 kg. Histological examination showed excellent bone-implant compatibility.

Required Column Overdesign Factor of 3D Steel Moment Frames with Square Tube Columns

2018 ◽  
Vol 763 ◽  
pp. 235-242
Author(s):  
Iathong Chan ◽  
Yuji Koetaka
Keyword(s):  
Plastic Deformation ◽  
Bearing Capacity ◽  
Ground Motion ◽  
Seismic Design ◽  
3D Analysis ◽  
Horizontal Load ◽  
Moment Frames ◽  
Steel Moment Frames ◽  
Load Bearing Capacity ◽  
Load Bearing

Steel moment frames are designed to ensure sufficient energy absorption capacity by achieving an entire beam-hinging collapse mechanism against severe earthquakes. Therefore, the column overdesign factor is stipulated in seismic design codes in some countries. For example in Japanese seismic design code, the specified column overdesign factor is 1.5 or more for steel moment frames with square tube columns. And this paper describes seismic response by 3D analysis of steel moment frames, and presents seismic demand for the column overdesign factor to keep the damage of square tube columns below the specified limit of plastic deformation. The major parameters are column overdesign factor, horizontal load bearing capacity, shape of frames and input direction of ground motion. In order to investigate 3D behavior of frames and correlation between plastic deformation of columns and column over design factor, apparent column overdesign factor, which is defined as the ratio of full plastic moment of the column (s) to the full plastic moment of the beam (s) projected in the input direction of the ground motion, is introduced. From the earthquake response analysis, it is clarified that the profile of maximum value of cumulative plastic deformation of columns to apparent column overdesign factor, with the similar horizontal load bearing capacity, are nearly identical regardless of number of stories, floor plan, and input direction of ground motion. As a result, the required column overdesign factor to keep the damage of columns below the limit of plastic deformation is proposed under the reliability index of 2.

Influence of Tool Wear on the Load-Bearing Capacity of Shear-Clinched Joints

2020 ◽  
Vol 404 ◽  
pp. 3-10
Author(s):  
Sebastian Wiesenmayer ◽  
Marion Merklein
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Bearing Capacity ◽  
Joint Strength ◽  
Tensile Load ◽  
Dissimilar Materials ◽  
High Strength ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Comparable Level

Shear-clinching allows the joining by forming of dissimilar materials with high differences between their mechanical properties without additional fasteners. Since the lower joining partner is indirectly shear cut during the process, even ultra-high strength materials can be joined. However, the cutting of the high-strength materials as well as the extrusion of the upper joining partner leads to high process forces and therefore to high tool loads. This applies in particular for the die, which is highly stressed during the cutting phase and therefore plastically deformed. Within the scope of this work, the influence of the occurring wear on the formation of the joint and its load-bearing capacity is analyzed for a scope of 500 strokes. For this purpose, press hardened 22MnB5 is used as lower joining partner. Its high strength leads to the plastic deformation of the cutting edge, which increases within the first 200 strokes. Afterwards only minor changes occur. Yet, no effect of the occurring wear on the joint formation and the joint strength, which was tested under shear and tensile load, could be determined. Functioning joints could still be produced for more than 500 strokes as the load-bearing capacity remained on a comparable level.

scholarly journals Load-Bearing Capacity and Fracture Behavior of Glass Fiber-Reinforced Composite Cranioplasty Implants

2017 ◽  
Vol 15 (4) ◽  
pp. e356-e361 ◽  
Author(s):  
Jaakko M. Piitulainen ◽  
Riina Mattila ◽  
Niko Moritz ◽  
Pekka K. Vallittu
Keyword(s):  
Plastic Deformation ◽  
Bearing Capacity ◽  
Glass Fiber ◽  
Resin Matrix ◽  
Fiber Reinforced ◽  
Loading Test ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Glass Fiber Reinforced ◽  
Elastic And Plastic Deformation

Background Glass fiber-reinforced composites (FRCs) have been adapted for routine clinical use in various dental restorations and are presently also used in cranial implants. The aim of this study was to measure the load-bearing capacity and failure type of glass FRC implants during static loading with and without interconnective bars and with different fixation modes. Methods Load-bearing capacities of 2 types of FRC implants with 4 different fixation modes were experimentally tested. The sandwich-like FRC implants were made of 2 sheets of woven FRC fabric, which consisted of silanized, woven E-glass fiber fabrics impregnated in BisGMA-TEGDMA monomer resin matrix. The space between the outer and inner surfaces was filled with glass particles. All FRC implants were tested up to a 10-mm deflection with load-bearing capacity determined at 6-mm deflection. The experimental groups were compared using non-parametric Kruskal-Wallis analysis with Steel-Dwass post hoc test. Results FRC implants underwent elastic and plastic deformation until 6-mm deflection. The loading test did not demonstrate any protrusions of glass fibers or cut fiber even at 10-mm deflection. An elastic and plastic deformation of the implant occurred until the FRC sheets were separated from each other. In the cases of the freestanding setup (no fixation) and the fixation with 6 screws, the FRC implants with 2 interconnective bars showed a significantly higher load-bearing capacity compared with the implant without interconnective bars. Conclusions FRC implants used in this study showed a load-bearing capacity which may provide protection for the brain after cranial bone defect reconstruction.

Sign in / Sign up

Export Citation Format

Share Document