Fire resistance of partially encased composite columns subjected to eccentric loading

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Abdelkadir Fellouh ◽  
Abdelkader Bougara ◽  
Paulo Piloto ◽  
Nourredine Benlakehal
Keyword(s):  
Bearing Capacity ◽  
Thermal Behaviour ◽  
Analytical Method ◽  
Calculation Method ◽  
Load Capacity ◽  
Simple Calculation ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Content Type ◽  
Composite Column

PurposeInvestigate the fire performance of eccentrically loaded concrete partially encased column (PEC), using the advanced calculation method (ANSYS 18.2, 2017) and the simple calculation method in Annex G of Eurocode 4 (EN 1994-1-2, 2005). This work examines the influence of a range of parameters on fire behaviour of the composite column including: eccentricity loading, slenderness, reinforcement, fire rating and fire scenario. In this study, ISO-834 (ISO834-1, 1999) was used as fire source.Design/methodology/approachCurrently, different methods of analysis used to assess the thermal behaviour of composite column exposed to fire. Analytical method named simplified calculation methods defined in European standard and numerical simulations named advanced calculation models are treated in this paper.FindingsThe load-bearing capacity of the composite column becomes very weak in the presence of the fire accident and eccentric loading, this recommends to avoid as much as possible eccentric loading during the design of construction building. The reinforcement has a slight influence on the temperature evolution; moreover, the reinforcement has a great contribution on the load capacity, especially in combined compression and bending. When only the two concrete sides are exposed to fire, the partially encased composite column presents a high load-bearing capacity value.Originality/valueThe use of a three-dimensional numerical model (ANSYS) allowed to describe easily the thermal behaviour of PEC columns under eccentric loading with the regard to the analytical method, which is based on three complex steps. In this study, the presence of the load eccentricity has found to have more effect on the load-bearing capacity than the slenderness of the composite column. Introducing a load eccentricity on the top of the column may have the same a reducing effect on the load-bearing capacity as the fire.

Load-bearing capacity and characteristic forms of destruction of furniture joints made with rastex 15 and P-10 clamex fasteners

2019 ◽  
Vol 106 ◽  
pp. 38-48
Author(s):  
Maciej Sydor ◽  
PIOTR POHL
Keyword(s):  
Bearing Capacity ◽  
Load Capacity ◽  
Bending Moment ◽  
Shear Forces ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Angular Deflection ◽  
Maximal Load ◽  
Rigidity Coefficient ◽  
The Relationship

Load-bearing capacity and characteristic forms of destruction of furniture joints made with rastex 15 and P-10 clamex fasteners. The study tested the relationship between the load and angular deflection in furniture joints. The tests were carried out for two types of fasteners and five types of materials: chipboard, MDF, hardwood plywood, glued pine boards and glued oak boards. The furniture joint samples contained two fasteners preloaded only with a bending moment (without application of shear forces). The results were converted per single fastener specifying: its maximal load capacity, 50 mrad (2.9°) limit deflection and rigidity coefficient. It was found that rigidity is a better structural property of the tested joint types than their load capacity. As far as rigidity is concerned, the most durable is the combination of oak glued board – rastex 15 fastener (13.2 Nm bending moment per fastener), while the least durable combination is chipboard – clamex P-10 fastener (4.8 Nm bending moment per fastener). Photographic documentation of damaged furniture joint samples was prepared and analysed. In case of chipboard and MDF combinations (where the load is determined by the combined material), the combined boards suffer a disastrous damage, while in combinations of plywood boards and pine or oak glued boards, (where the capacity is determined by the fastener), both clamex P10 and rastex 15 fasteners are damaged.

Paper 5: The Hydrosphere

1967 ◽  
Vol 182 (14) ◽  
pp. 33-40
Author(s):  
D. Dowson ◽  
C. M. Taylor
Keyword(s):  
Bearing Capacity ◽  
Recent Work ◽  
Load Capacity ◽  
Thermal Distortion ◽  
Approximate Analysis ◽  
Fluid Inertia ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Inertia Effects ◽  
Preliminary Examination

A preliminary examination of the bearing indicates that it is not capable of hydrodynamic action as the fluid film is parallel in the direction of motion. However, in practice it has been found that the bearing can support considerable loads. Earlier papers by the authors have examined the proposal of Shaw and Strang that the inertia of the lubricant could account for the load capacity of the bearing. This contention was rejected by the authors, and after other possible explanations had been investigated it was concluded that thermal distortion was the most likely cause of the load-bearing capacity. In this paper recent work will be reported which supports this proposal. The analysis of fluid inertia effects is summarized for a continuous hemispherical seat whose surface is disturbed only by the central lubricant supply hole (the grooveless case). The paper also presents experimental results and an approximate analysis of the thermal distortion for a hydrosphere seat with four lubricant grooves running from the supply hole to the equator along longitudinal lines.

scholarly journals Analysis of Interference-Fit Joints

2021 ◽  
Vol 11 (23) ◽  
pp. 11428
Author(s):  
Jerzy Madej ◽  
Mateusz Śliwka
Keyword(s):  
Bearing Capacity ◽  
Load Capacity ◽  
Fem Simulation ◽  
Load Bearing Capacity ◽  
Measuring Device ◽  
Plastic Deformations ◽  
Interference Fit ◽  
Load Bearing ◽  
Press Fit ◽  
The Press

Interference fit joints have been widely used in many engineering constructions, in particular in electric motors. It is of particular importance to calculate the load capacity of press-fit joints, especially in the overload ranges of construction to estimate the safety factor. The article presents a FEM numerical simulation of pressing the shaft into the hub, taking into account various types of fits. The results of numerical simulations presented in the article were positively verified with the MTS measuring device, which confirmed the correctness of the numerical model. So far, the load-bearing capacity of press-fit joints has been calculated from Lame’s formulas. The results of the load capacity of the joints obtained by the FEM simulation were compared with the results obtained from Lame’s formula. The comparison shows that when designing interference fit joints, attention should be paid to the fact that the press-in process, depending on the type of fit, may be elastic-plastic. Plastic deformations in the contact zone of the joint affect its load-bearing capacity. Therefore, the design of press-fit joints should not be based on Lame’s formulas, which do not take into account the range of plastic work of the material.

scholarly journals DEVELOPMENT AND IMPROVEMENT OF BEAM STRUCTURES ON THE BASIS OF COMPOSITE LOGS’ GIRDERS

2018 ◽  
Vol 15 (5) ◽  
pp. 760-773 ◽  
Author(s):  
V. A. Utkin ◽  
P. N. Kobzev ◽  
E. G. Shatunova
Keyword(s):  
Bearing Capacity ◽  
Calculation Method ◽  
Steel Plates ◽  
Load Bearing Capacity ◽  
Beam Structures ◽  
Load Bearing ◽  
Dowel Connections ◽  
Design And Construction ◽  
Composite Girders

Introduction. Experience in the design and construction of beam structures of wooden bridges with composite girders indicates the possibility of increasing the bearing capacity and the length of the overlapped spans.Materials and methods. The most rational load-bearing elements of composite girders can serve as the logs edged on two edges with the diameter of 28 to 32 cm with the maximum use of the most durable layers of sapwood and dowel connections of steel plates with blind cylindrical nags.Results. In contrast to the compounds of composite girders on lamellar nails, the proposed connection greatly simplifies the process of making the composite girders. Such connection also allows using the logging along the length, combining into three or four tiers and increasing the length of the span.Discussion and conclusion. The proposed solutions increase the load-bearing capacity of composite girders and allow them to be used in the structures of wooden bridges under modern automotive loads. Moreover, the calculation method of composite girders on the basis of the method of forces and discrete placement in the beams between the logs of concentrated elastic-datum shear bonds is developed.

Parametric design of surface textures on journal bearing

2015 ◽  
Vol 67 (4) ◽  
pp. 359-369 ◽  
Author(s):  
Hui Zhang ◽  
Guangneng Dong ◽  
Meng Hua ◽  
Feifei Guo ◽  
Kwai Sang Chin
Keyword(s):  
Bearing Capacity ◽  
Journal Bearing ◽  
Parametric Design ◽  
Load Bearing Capacity ◽  
Rectangular Array ◽  
Load Bearing ◽  
Content Type ◽  
Surface Textures ◽  
Capacity Enhancement ◽  
Hydrodynamic Influence

Purpose – The main purpose of this paper is to understand and model the hydrodynamic influence of surface textures on journal bearings. Design/methodology/approach – In the model, a rectangular array of circle dimples is used to modify the film thickness expression. In full film and cavitation regions, classical Reynolds equation and Reynolds boundary condition are used as the governing equations, respectively. By setting high load bearing capacity as the main optimal goal, the influence of textures on tribological characteristics is studied to get the optimal distribution and parameters of textures. Findings – The results suggest that the load bearing capacity of a journal bearing may be improved through appropriate arrangement of textures partially covering its sleeve. The reduction of the cavitation area may also be achieved by arranging the textures in divergent region. With a high density distribution of textures which have step depths varying linearly along the circumferential direction of the bearing, the load bearing capacity enhancement seems to give good performance. Comparing with smooth bearing, the load bearing capacity enhancement of such textures is about 56.1 per cent, although the influence of texture diameters for the same area density seems insignificant. Originality/value – The paper shows how surface textures can be designed on journal bearing to improve its tribological performances.

Load Bearing Capacity of Oil Film Bearing Research

2010 ◽  
Vol 42 ◽  
pp. 255-258
Author(s):  
Hong Chao Fan ◽  
Jing Lin Tong ◽  
Xin Hua Yi ◽  
Jin Bao He ◽  
Jian Xi Yang
Keyword(s):  
Bearing Capacity ◽  
Design Method ◽  
Structural Characteristics ◽  
Load Capacity ◽  
Parameters Optimization ◽  
Design Parameters ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Oil Film ◽  
Application Requirements

The oil film have many excellences such as bigger load bearing capacity, longer life, wider velocity range, lower friction etc. The traditional design method is experience test. Even the design parameters could meet the application requirements, but they can not exert the best performance of the oil film bearing. The relationship between load bearing capacity and materials, lubricants, design parameters and structural characteristics of oil film bearing was analysed. To improve the load capacity and run at the optimal state, the objective function was built to optimize the main parameters. Optimization results showed that the load bearing capacity has been greatly improved.

scholarly journals RESERVE CAPACITY OF LONGITUDINAL BEAM OF WAGON TRUCK UNDER THE ACTION OF UNIFORMLY DISTRIBUTED LOADING

2020 ◽  
Vol 1 (154) ◽  
pp. 50-56
Author(s):  
О. Kuznetzov ◽  
О. Rubanenko ◽  
О. Khrenov ◽  
E. Rafalskiy
Keyword(s):  
Bearing Capacity ◽  
Load Capacity ◽  
Limit State ◽  
Design Stage ◽  
Power Calculation ◽  
Resource Saving ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Allowable Stresses ◽  
Permissible Stresses

Priority directions and measures among the main branches of urban electric transport are resource saving in the subway transportation system during its operation. First of all, this problem must be solved by scientific support, that is, at the stage of designing parts and components of vehicles. One of the main tasks that are solved at the design stage is to increase the load-bearing capacity of the parts by analyzing their stress-strain state. The article is devoted to the calculation of the load capacity reserve of the longitudinal beam of the front subway trolley under the action of evenly distributed over the entire length of the load without taking into account the transverse forces. The priority of the research topic is substantiated, the purpose and tasks are formulated. Two approaches to the power calculation of the bearing capacity of the longitudinal beam are introduced: the calculation of the permissible stresses and the limit state. In both cases elastic models of beams are considered. In the case of calculation on the limit state, the mechanics of the occurrence of plastic hinges at the places of rigid fixing of the ends of the beam are first substantiated. The beam still retains its load capacity. With the further growth of the external load, the emergence of a plastic hinge is justified even in the middle of the beam with the simultaneous loss of the beam of the bearing capacity. To simulate the behavior of the beam according to its characteristics, including the stress and the degradation condition of its load capacity, the mathematical formulation of the problem of calculating the load capacity of the longitudinal beam when calculating the permissible stresses and the limit state without taking into account the transverse force. The load-bearing capacity of the longitudinal beam in the calculation of permissible stresses and the limit state is analyzed. The analysis of the obtained results allows us to judge the effectiveness of the proposed mathematical model as a whole. The obtained equations for the maximum allowable load when calculating the limit state and the allowable stresses allow us to reliably estimate the bearing capacity of the longitudinal beam in both cases. The increase in the bearing capacity of the beam in the case of calculation on the limit is three times. The conclusions about the adequacy of the analysis of the bearing capacity of the longitudinal beam bearing capacity were made. Keywords: resource saving, beam, bearing capacity, allowable stresses, limit state.

Load-bearing capacity and resonance stability of inelastic beams and plane trusses with initial defects

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Dragan D. Milašinović ◽  
Ljiljana Kozarić ◽  
Smilja Bursać ◽  
Miroslav Bešević ◽  
Ilija Miličić ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Damage Mechanics ◽  
Ductile Material ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Content Type ◽  
Stability Problems ◽  
Material Defects ◽  
Fundamental Frequencies ◽  
Stiffness Reduction

PurposeThe purpose of this paper is to contribute to the solution of the buckling and resonance stability problems in inelastic beams and wooden plane trusses, taking into account geometric and material defects.Design/methodology/approachTwo sources of non-linearity are analyzed, namely the geometrical non-linearity due to geometrical imperfections and material non-linearity due to material defects. The load-bearing capacity is obtained by the rheological-dynamical analogy (RDA). The RDA inelastic theory is used in conjunction with the damage mechanics to analyze the softening behavior with the scalar damage variable for stiffness reduction. Based on the assumed damages in the wooden truss, the corresponding external masses are calculated in order to obtain the corresponding fundamental frequencies, which are compared with the measured ones.FindingsRDA theory uses rheology and dynamics to determine the structures' response, those results in the post-buckling branch can then be compared by fracture mechanics. The RDA method uses the measured P and S wave velocities, as well as fundamental frequencies to find material properties at the limit point. The verification examples confirmed that the RDA theory is more suitable than other non-linear theories, as those proved to be overly complex in terms of their application to the real structures with geometrical and material defects.Originality/valueThe paper presents a novel method of solving the buckling and resonance stability problems in inelastic beams and wooden plane trusses with initial defects. The method is efficient as it provides explanations highlighting that an inelastic beam made of ductile material can break in any stage from brittle to extremely ductile, depending on the value of initial imperfections. The characterization of the internal friction and structural damping via the damping ratio is original and effective.

scholarly journals NEURINGER-ROSEINWEIG MODEL BASED LONGITUDINALLY ROUGH POROUS CIRCULAR STEPPED PLATES IN THE EXISTENCE OF COUPLE STRESS

2020 ◽  
Vol 60 (3) ◽  
pp. 259-267
Author(s):  
Yoginibahen Devendrasinh Vashi ◽  
Rakesh Manilal Patel ◽  
Gunamani Biswanath Deheri
Keyword(s):  
Bearing Capacity ◽  
Couple Stress ◽  
Load Capacity ◽  
Continuum Theory ◽  
Type Equation ◽  
Stress Effect ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Closed Form Solutions ◽  
The Impact

This study intents to scrutinize the impact of ferrofluid in the presence of couple stress for longitudinally rough porous circular stepped plates. The influence of longitudinal surface roughness is developed using the stochastic model of Christensen and Tonder for nonzero mean, variance and skewness. Neuringer-Roseinweig model is adopted for the influence of ferrofluid. The couple stress effect is characterized by Stoke’s micro continuum theory. The modified Reynolds’ type equation is stochastically averaged and solved by no-slip boundary conditions. The closed form solutions for load bearing capacity and film pressure are obtained as a function of different parameters and plotted graphically. It is perceived that the load capacity gets elevated owing to the combined influence of magnetization and couple stress when the proper choice of roughness parameters (negatively skewed, standard deviation) is in place. Porosity and roughness (positively skewed) adversely affect bearing’s performance. The graphical and tabular analysis shows that there is a significant growth in load bearing capacity compared to the conventional lubricant case.

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