scholarly journals Numerical modelingof a composite section element from thin-walled profiles taking into account the initial geometric imperfections

2020 ◽  
Vol 17 (1) ◽  
pp. 82-86
Author(s):  
D. A. Prostakishina ◽  
◽  
N. D. Korsun ◽  
Keyword(s):  
Bearing Capacity ◽  
Compressive Force ◽  
Stability Loss ◽  
Load Bearing Capacity ◽  
Geometric Imperfections ◽  
Load Bearing ◽  
Composite Section ◽  
Initial Geometric Imperfections ◽  
Thin Walled ◽  
The Stability

The article describes the process of numerical simulation of a composite symmetric section element made of thin-walled Sigma profiles operating under conditions of longitudinal compressive force with bending, taking into account the initial geometric imperfections. At numerical modeling, the main criterion of the load-bearing capacity exhaustion in case of eccentric compression is the stability loss in one of the forms. However, for thin-walled elements, the loss of local stability does not mean that the load-bearing capacity is completely exhausted, since the element continues to carry the load, but to a lesser extent. Therefore, simulation was carried out in two stages: initially, in the elastic formulation, the possible buckling modes were determined, afterwards, there was made calculation on the deformed pattern taking into account possible imperfections.

Safety factor determining for space trusses by non-linear analysis and artificial neural network method

2013 ◽  
Vol 20 (3) ◽  
pp. 277-284
Author(s):  
Mehrzad Mohabbi Yadollahi ◽  
Fatma Karagöl ◽  
Mehmet Akif Kaygusuz ◽  
Rıza Polat ◽  
Ramazan Demirboga
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Bearing Capacity ◽  
Safety Factor ◽  
Load Bearing Capacity ◽  
Geometric Imperfections ◽  
Load Bearing ◽  
Non Linear ◽  
Initial Geometric Imperfections ◽  
Space Trusses

AbstractDetermining a feasible safety factor for space trusses is an important phase in structural analysis that could have economic benefits. We know there are many kinds of imperfections in structural elements, which include both material and geometric flaws. Predicting factual behavior of structures is very difficult and occasionally impossible. Elements with initial geometric imperfections in space trusses are a common phenomenon, in addition, equivalent initial geometric imperfections can be applied for modeling of residual stresses or eccentric loading effect. The number of members in the space structures is usually high as is the diversity in the kind of initial imperfection. Therefore, there is a high likelihood that models must be analyzed. The structure must be analyzed with non-linear methods, making these approaches time consuming, and potentially uneconomical. In this study, we selected 30 cases for random analysis based on Monte Carlo methods to find the bearing capacity of the space truss. We attained results from the LUSAS program LUSAS Modeller, Version 13, UK program and these were then exported as input data to the Artificial Neural Network (ANN) program. A reasonable neural network has been found of predicting another 30 cases for load bearing capacity without any analysis and only based on the neural network program. Finally, a new approach for determining the load capacity of the space trusses was extracted and we predicted the occurrence possibility of the convenience load bearing capacity in 60 cases.

Composite action in masonry walls under vertical in-plane loading: experimental results compared with predictions

2015 ◽  
Vol 42 (7) ◽  
pp. 449-462
Author(s):  
A.T. Vermeltfoort ◽  
D.R.W. Martens
Keyword(s):  
Bearing Capacity ◽  
Concrete Beam ◽  
Concrete Beams ◽  
Compressive Force ◽  
Reinforced Concrete Beams ◽  
Elastic Behavior ◽  
Masonry Walls ◽  
Load Bearing Capacity ◽  
Cracking Behavior ◽  
Load Bearing

The results of five experimental test series on masonry walls supported by reinforced concrete beams or slabs are reported and compared to theoretical predictions of the load bearing capacity. The experiments were performed on deep masonry beams built with respectively calcium silicate and clay brick. Investigated parameters were: position of the supports, concrete beam-masonry interface, concrete beam stiffness, type of loading, and height of masonry wall and concrete beam. Based on literature, the method proposed by Davies and Ahmed as well as the method according to Eurocode 6 were used to estimate the load bearing capacity of the tested masonry walls supported by concrete beams. The method of Davies and Ahmed allows for the determination of the stresses and stress resultants in the masonry. The analysis shows that near the support an inclined compressive force acts at the bed joint, which means that a shear-compression stress state exists in the bed joint. Strength evaluation has been carried out using the Mann-Müller criterion that is adopted in Eurocode 6. Based on the test results, it may be concluded that both methods yield conservative values of the load bearing capacity, as could be expected. Before cracking a linear elastic behavior was observed, while after cracking a strut-and-tie model may be applied. To develop more accurate design models, it is recommended to investigate the post-cracking behavior in more detail.

scholarly journals BEHAVIOUR OF VERTICAL CYLINDRICAL TANK WITH LOCAL WALL IMPERFECTIONS

2019 ◽  
Vol 25 (3) ◽  
pp. 287-296 ◽  
Author(s):  
Antanas Šapalas ◽  
Gintas Šaučiuvėnas ◽  
Konstantin Rasiulis ◽  
Mečislovas Griškevičius ◽  
Tomas Gečys
Keyword(s):  
Bearing Capacity ◽  
Extreme Points ◽  
The European Union ◽  
Maintenance Period ◽  
Cylindrical Tank ◽  
Load Bearing Capacity ◽  
Complex Investigation ◽  
Load Bearing ◽  
Thin Walled Structures ◽  
Thin Walled

Design of modern thin-walled metal structures is widely used around the world. In recent decades, more comprehensive research is carried out to investigate the behaviour of various thin-walled structures. Generally, the structure with regular geometry is investigated. In various countries such as USA, Russia, and the European Union issued the standards on regulation of the construction, design and maintenance of thin-walled structures. The actually used period of tanks usually is longer than recommendatory period. Recommendatory maintenance period of metal tanks is 15–20 years. Therefore, for such structures one of the most considerable questions is the residual load bearing capacity beyond the end of the maintenance period. This phase of using of structures is associated with complex investigation and numerical analysis of thin-walled structures. In this paper the load bearing capacity of the steel wall of the existing over-ground vertical cylindrical tank in volume of 5,000 m3 with a single defect and with a few contiguous local defects of the shape is analyzed. Calculations carried out are taking into account all the imperfections of the wall geometry. A major goal of the research – developing a realistic numerical model of the object analyzed, taking into account all the imperfections, determining the wall stress and strain state, exploring the places of extreme points, calculating the residual load bearing capacity of the tank and scrutinizing possible strengthening schemes for defective areas.

Konstruktive Injektion von historischem Mauerwerk mit mineralisch- oder polymergebundenen Mörteln / Structural injection of historical masonry using mineral or polymer based grouts

1999 ◽  
Vol 5 (1) ◽  
pp. 73-98 ◽  
Author(s):  
D. Van Gemert ◽  
E.-E. Toumbakari ◽  
L. Schueremans
Keyword(s):  
Mechanical Properties ◽  
Bearing Capacity ◽  
Masonry Structures ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Recent Developments ◽  
Safety And Reliability ◽  
Historical Masonry ◽  
The Stability

Abstract Recent developments in injection grouts used for consolidation are proposed. Special compositious have been developed, made out of lime, cement and pozzolan. The stability, the viscosity and the mechanical properties are illustrated. Comparison is made with polymer grouts and with double injections using mineral and polymer grouts consequently. The influence of injections on the load-bearing capacity of the masonry is calculated. Some elements for the judgment of the safety and reliability of masonry structures are pointed out.

IMPROVING CONSTRUCTIVE SOLUTION OF BEAM WITH CORRUGATED WALL

2016 ◽  
Vol 6 (2) ◽  
pp. 4-9 ◽  
Author(s):  
Aleksey O. LUKIN ◽  
Vadim Yu. ALPATOV ◽  
Dmitriy D. CHERNYSHEV
Keyword(s):  
Bearing Capacity ◽  
Carrying Capacity ◽  
Local Stability ◽  
Local Resistance ◽  
Preliminary Assessment ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
The Stability ◽  
Corrugated Wall ◽  
Corrugated Beam

The analysis of improving ways to test for load-bearing structures - metal beams with corrugated wall was conducted. Weak places, limiting their load-bearing capacity were determined. It was found that the criterion for determining the carrying capacity of thin-walled corrugated beam is its local resistance. The author's solution to increase the local stability of the corrugated wall beams was suggested. Author's solution is to give the corrugated wall of further extruded profile of different geometry. The influence of the shape and size of punching the wall on the carrying capacity of corrugated beams was determined. The studies confirming the effectiveness of the proposed constructive solutions increase the stability of the corrugated wall are conducted. Preliminary assessment of the degree of increase of the bearing capacity of the beam by punching its wall is obtained.

scholarly journals Degradation of Axial Ultimate Load-Bearing Capacity of Circular Thin-Walled Concrete-Filled Steel Tubular Stub Columns after Corrosion

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 795 ◽  
Author(s):  
Fengjie Zhang ◽  
Junwu Xia ◽  
Guo Li ◽  
Zhen Guo ◽  
Hongfei Chang ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Ultimate Load ◽  
Steel Tube ◽  
Parameter Analysis ◽  
Loading Test ◽  
Steel Tubes ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Thin Walled ◽  
Stub Columns

This work aimed to investigate the effects of steel tube corrosion on the axial ultimate load-bearing capacity (AULC) of circular thin-walled concrete-filled steel tubular (CFST) members. Circular thin-walled CFST stub column specimens were made of steel tubes with various wall-thicknesses. These CFST column specimens were subjected to an accelerated corrosion test, where the steel tubes were corroded to different degrees of corrosion. Then, these CFST specimens with corroded steel tubes experienced an axial static loading test. Results show that the failure patterns of circular thin-walled CFST stub columns with corroded steel tubes are different from those of the counterpart CFST columns with ordinary wall-thickness steel tubes, which is a typical failure mode of shear bulging with slight local outward buckling. The ultimate strength and plastic deformation capacity of the CFST specimens decreased with the increasing degree of steel corrosion. The failure modes of the specimens still belonged to ductile failure because of the confinement of outer steel tube. The degree of steel tube corrosion, diameter-to-thickness ratio, and confinement coefficient had substantial influences on the AULC and the ultimate compressive strength of circular thin-walled CFST stub columns. A simple AULC prediction model for corroded circular thin-walled CFST stub columns was presented through the regression of the experimental data and parameter analysis.

Axial Compression Experimental Research of RPC Filled Steel Tube Columns

2010 ◽  
Vol 150-151 ◽  
pp. 198-202
Author(s):  
Zhi Gang Yan ◽  
Yan Huang ◽  
Ming Zhe An
Keyword(s):  
Bearing Capacity ◽  
Ultimate Load ◽  
Engineering Application ◽  
High Strength ◽  
Steel Tube ◽  
Loading Capacity ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
The Stability ◽  
Reactive Powder

Reactive Powder Concrete (RPC) is a new kind of building material with high strength and other good performance. The combination of RPC and steel tube will compensate the brittleness of RPC and enhance the stability of steel tube, and the loading capacity of the RPC filled steel tube will be improved. Five RPC filled steel tube columns are designed and tested to obtain the ultimate load bearing capacity, the deformation and the strain information. During the loading process, the concrete and the steel tube of the RPC filled steel tube columns are loaded simultaneously. The loading results show that the deformation of the RPC filled steel tube columns are mainly in elastic phase before the loading capacity is up to the ultimate value. The test load decreases to be 80%~90% of the ultimate loading value and then it changes to be smooth. The failure mode of the RPC filled steel tube columns is ductile. The test loading capacity is compared with the formula from the reference. The tested ultimate load bearing capacity of the steam cured RPC filled steel tube columns is higher than the calculated value. The calculated value is safe for the engineering application. The study is useful for the research and application of RPC filled steel tube column.

Experiments on Wall Panels with One-Sided Board Sheathing for Timber Structures

2017 ◽  
Vol 1144 ◽  
pp. 3-8
Author(s):  
Jiří Celler ◽  
Jakub Dolejs ◽  
Vera Hlavata
Keyword(s):  
Bearing Capacity ◽  
Cross Section ◽  
Timber Structures ◽  
Bearing Material ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Glued Laminated Timber ◽  
Wall Panels ◽  
The Stability ◽  
Shaped Cross Section

Timber elements with an I-shaped cross-section are used as supporting elements in wall, ceiling and roof panels of light timber frames. The reinforcement of the panel (I-stud) is provided by means of glued timber composite I-shaped element consisting of a web made of a wood-based desk embedded into flanges of solid or glued laminated timber. The stability of the wall panels is usually ensured by sided board sheathing, which prevents buckling of studs in the plane of the wall or their twist. Walls with one-side board sheathing are used for some types of modern timber structures and their load bearing capacity is determined for situation when one-side sheathing burns down during fire or sheathing is not made of a load-bearing material.

scholarly journals LOAD-BEARING CAPACITY ANALYSIS FOR STRUCTURAL COLD-FORMED MEMBERS SUBJECTED TO CENTRAL COMPRESSION

2021 ◽  
pp. 28-42
Author(s):  
А.V. Perelmuter ◽  
◽  
V.V. Yurchenko ◽  
Keyword(s):  
Bearing Capacity ◽  
Local Buckling ◽  
Structural Members ◽  
Design Code ◽  
Distortional Buckling ◽  
Load Bearing Capacity ◽  
Cross Sectional ◽  
Load Bearing ◽  
Composite Section ◽  
Flexural Torsional Buckling

Abstract. The main purpose of the research was a deep analysis and verification of the consistency and completeness of the design code relating to calculation of load-bearing structural members made from cold-formed profiles. The work has been done in close connection with the implementation on the territory of Ukraine of this design code. The article has discussed and investigated the load-bearing capacity of structural members made of cold-formed profiles subjected to the action of central compression. A system of constraints has been presented, in which the strength and buckling constraints for thin-walled cold-formed column members are formulated, taking into account their possible post-buckling behavior, namely, the ability to resist external loads and effects even after the occurrence of the local buckling and/or distortional buckling phenomenon. The performed load-bearing capacity investigation has shown that for the mono-symmetric cold-formed profiles, the flexural-torsional buckling is determinative. For such cold-formed profiles, the effect of the overall dimensions ratio (flange width to web height) on the load-bearing capacity of cold-formed profiles has been estimated. It has been shown that for the same cross-sectional area the load-bearing capacity of a column structural member made from cold-formed profile and subjected to axial compression can be significantly increased by assigning an optimal ratio of flange width to web height. The paper also has presented the results of the load-bearing capacities for the structural cold-formed members subjected to central compression, calculated according to the design standard DSTU-N B EN 1993-1-3: 2012 and according to the design code DBN V.2.6-198: 2014. It has been shown that in some cases the difference in the assessment of the load-bearing capacity for such structural cold-formed members reached 25%. A comparison of the load-bearing capacities for the action of the central compression has been made for structural cold-formed members made from a C-shaped profile and with a composite section of two C-shaped profiles. It has been shown that the load-bearing capacity of the structural cold-formed member of the composite section exceeds the load-bearing capacity of the member with single C-shaped profile by more than 3 times, while cross-section areas of these structural members differ only doubly.

Sign in / Sign up

Export Citation Format

Share Document