Experimental and numerical assessment of CHS-RHS T-joints with chords subjected to axial tensile forces

Hollow steel sections are widely used in the construction industry due to their mechanical properties. Joints used in these structures are the subject of research because of their singular and critical behavior. Joints containing chords with more slender cross-sections and axially loaded are still a challenge for design, especially in joints with circular hollow sections (CHS) in the braces and rectangular hollow sections (RHS) in the chords. In this context, this work aimed to study joints formed by a combination of CHS braces subjected to compression loads and RHS chords axially loaded with tension, welded as T-joints. Experimental tests, a numerical model using finite elements, and a parametric analysis were developed. A new equation for the chord stress function was proposed, including joints containing chords with semi-compact sections in tension. The joint resistance values obtained through the numerical models were compared with the equations from ISO 14346:2013 and with the proposed equation. It was observed that, for the numerical models with geometric properties inside the normative validity ranges of ISO 14346:2013, the mean rate of analytical by numerical joint resistance results was equal to 68%, using either the normative or the proposed equation. In the same way, for models outside the current validity ranges, either the proposed equation or the modified equation from ISO 14346:2013 could be used to design CHS-RHS T-joints with the geometric and material properties analyzed.

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The Influence of the Layer Arrangement on the Distortional Post-Buckling Behavior of Open Section Beams

Materials ◽

10.3390/ma13133002 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3002

Author(s):

Tomasz Kubiak ◽

Mariusz Urbaniak ◽

Filip Kazmierczyk

Keyword(s):

Cross Sections ◽

Numerical Models ◽

Experimental Tests ◽

Distortional Buckling ◽

Buckling Mode ◽

Layer Arrangement ◽

Reinforced Polymer ◽

Glass Fiber Reinforced ◽

Buckling Behavior ◽

Post Buckling

The paper deals with the design of the stacking sequence of layers in the laminate beams with open-cross sections in order to create the desired behavior in the post-buckling range. Laminate beams with channel and lipped channel cross-sections made of glass fiber reinforced polymer (GFRP) laminate with different layer arrangements (symmetrical and nonsymmetrical) have been considered. In case of the nonsymmetrical stacking sequences, hygro-thermally curvature stable (HTCS) laminates have been taken into account. Pure bending was assumed as the type of load. In the case of beams with open cross-sections, this load type can cause the lateral-distortional buckling mode. A parametric study was performed to analyze the influence of layer arrangement on post-buckling behavior. The finite element method was used to developed numerical models and conduct simulations. Additionally, the experimental tests of the channel section beams were performed in order to validate the developed numerical models.

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Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research

Polymers ◽

10.3390/polym13010137 ◽

2020 ◽

Vol 13 (1) ◽

pp. 137

Author(s):

Artur Andrearczyk ◽

Bartlomiej Konieczny ◽

Jerzy Sokołowski

Keyword(s):

Polymer Material ◽

High Speed ◽

Numerical Models ◽

Flow Analysis ◽

Experimental Tests ◽

Strength Analysis ◽

Compressor Wheel ◽

Operational Characteristics ◽

3D Printed ◽

Novel Method

This paper describes a novel method for the experimental validation of numerically optimised turbomachinery components. In the field of additive manufacturing, numerical models still need to be improved, especially with the experimental data. The paper presents the operational characteristics of a compressor wheel, measured during experimental research. The validation process included conducting a computational flow analysis and experimental tests of two compressor wheels: The aluminium wheel and the 3D printed wheel (made of a polymer material). The chosen manufacturing technology and the results obtained made it possible to determine the speed range in which the operation of the tested machine is stable. In addition, dynamic destructive tests were performed on the polymer disc and their results were compared with the results of the strength analysis. The tests were carried out at high rotational speeds (up to 120,000 rpm). The results of the research described above have proven the utility of this technology in the research and development of high-speed turbomachines operating at speeds up to 90,000 rpm. The research results obtained show that the technology used is suitable for multi-variant optimization of the tested machine part. This work has also contributed to the further development of numerical models.

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Numerical and experimental evaluation of masonry prisms by finite element method

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952017000200010 ◽

2017 ◽

Vol 10 (2) ◽

pp. 477-508 ◽

Cited By ~ 2

Author(s):

C. F.R. SANTOS ◽

R. C. S. S. ALVARENGA ◽

J. C. L. RIBEIRO ◽

L. O CASTRO ◽

R. M. SILVA ◽

...

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

High Strength Concrete ◽

Numerical Models ◽

High Strength ◽

Experimental Tests ◽

Experimental Results ◽

Concrete Blocks ◽

Micro Modeling ◽

Modeling Strategy

Abstract This work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar) was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the mechanisms responsible for failure.

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Centrifuge study of seismic response of soil-nailed walls supporting a footing on the ground surface

Géotechnique ◽

10.1680/jgeot.21.00157 ◽

2021 ◽

pp. 1-41

Author(s):

Mohammad Hassan Baziar ◽

Alireza Ghadamgahi ◽

Andrew John Brennan

Keyword(s):

Ground Surface ◽

Soil Surface ◽

Seismic Stability ◽

Soil Nails ◽

Model Soil ◽

Centrifuge Tests ◽

Axial Tensile ◽

Tensile Forces ◽

Surcharge Load ◽

Seismic Loadings

Seismic design of soil-nailed walls requires demonstrations of tolerable ranges of wall movements, especially when a surcharge load exists near the wall. In this study, the effect of surcharge location on seismically induced wall movements was investigated using four centrifuge tests. The axial tensile forces, developed along the soil nails during the seismic loadings, were also measured during the tests. At 50g centrifugal acceleration, model tests represented a 12-m-high prototype wall reinforced with five rows of soil nails. To apply a surcharge stress of 30 kPa at the specified location relative to the wall for each model test, a rigid footing was placed on the soil surface. The model soil-nailed walls were subjected to three successive earthquake motions. Surprisingly, it was found that the model wall with the footing located behind the soil-nailed region experienced the largest seismic movements, even more than when the footing was directly behind the wall. Further, the tests showed that the lower soil nails played a key role in the wall stability during earthquake shaking, acting as a pivot for the pre-collapse cases tested, whereas the upper soil nails needed to be sufficiently extended to properly contribute to the seismic stability of the wall.

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Numerical Investigation of Ductile Fracture in Pipelines Under Complex Loading Using a Phenomenological Damage Model

10.1115/pvp2021-62017 ◽

2021 ◽

Author(s):

Iago S. Santos ◽

Diego F. B. Sarzosa

Keyword(s):

Ductile Fracture ◽

Mechanical Response ◽

Numerical Study ◽

Damage Model ◽

Stress Triaxiality ◽

Numerical Procedure ◽

Complex Loading ◽

Experimental Tests ◽

Compact Tension ◽

Axial Tensile

Abstract This paper presents a numerical study on pipes ductile fracture mechanical response using a phenomenological computational damage model. The damage is controlled by an initiation criterion dependent on the stress triaxiality and the Lode angle parameter, and a post-initiation damage law to eliminate each finite element from the mesh. Experimental tests were carried out to calibrate the elastoplastic response, damage parameters and validate the FEM models. The tested geometries were round bars having smooth and notched cross-section, flat notched specimens under axial tensile loads, and fracture toughness tests in deeply cracked bending specimens SE(B) and compact tension samples C(T). The calibrated numerical procedure was applied to execute a parametric study in pipes with circumferential surface cracks subjected to tensile and internal pressure loads simultaneously. The effects of the variation of geometric parameters and the load applications on the pipes strain capacity were investigated. The influence of longitudinal misalignment between adjacent pipes was also investigated.

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Super-long span bridge aerodynamics: on-going results of the TG3.1 benchmark test – Step 1.2

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.2644 ◽

2019 ◽

Author(s):

Giorgio Diana ◽

Stoyan Stoyanoff ◽

Andrew Allsop ◽

Luca Amerio ◽

Tommaso Argentini ◽

...

Keyword(s):

Numerical Models ◽

Experimental Tests ◽

Numerical Comparison ◽

Aeroelastic Stability ◽

Turbulent Wind ◽

Long Span Bridges ◽

Buffeting Response ◽

Long Span ◽

Long Span Bridge ◽

Sectional Model

<p>This paper is part of a series of publications aimed at the divulgation of the results of the 3-step benchmark proposed by the IABSE Task Group 3.1 to define reference results for the validation of the software that simulate the aeroelastic stability and the response to the turbulent wind of super-long span bridges. Step 1 is a numerical comparison of different numerical models both a sectional model (Step 1.1) and a full bridge (Step 1.2) are studied. Step 2 will be the comparison of predicted results and experimental tests in wind tunnel. Step 3 will be a comparison against full scale measurements.</p><p>The results of Step 1.1 related to the response of a sectional model were presented to the last IABSE Symposium in Nantes 2018. In this paper, the results of Step 1.2 related to the response long-span full bridge are presented in this paper both in terms of aeroelastic stability and buffeting response, comparing the results coming from several TG members.</p>

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NUMERICAL ANALYSIS OF CORRUGATED STEEL PLATE BRIDGE WITH REINFORCED CONCRETE RELIEVING SLAB

Journal of Civil Engineering and Management ◽

10.3846/13923730.2014.914092 ◽

2015 ◽

Vol 22 (5) ◽

pp. 585-596 ◽

Cited By ~ 11

Author(s):

Damian BEBEN ◽

Adam STRYCZEK

Keyword(s):

Reinforced Concrete ◽

Numerical Analysis ◽

Steel Plate ◽

Numerical Models ◽

Experimental Tests ◽

Bridge Engineering ◽

Steel Plates ◽

The Finite Element Method ◽

Calculation Results ◽

Rc Slab

The paper presents a numerical analysis of corrugated steel plate (CSP) bridge with reinforced concrete (RC) relieving slab under static loads. Calculations were made based on the finite element method using Abaqus software. Two computation models were used; in the first one, RC slab was used, and the other was without it. The effect of RC slab to deformations of CSP shell was determined. Comparing the computational results from two numerical models, it can be concluded that when the relieving slab is applied, substantial reductions in displacements, stresses, bending moments and axial thrusts are achieved. Relative reductions of displacements were in the range of 53–66%, and stresses of 73–82%. Maximum displacements and bending moments were obtained at the shell crown, and maximum stresses and axial thrusts at the quarter points. The calculation results were also compared to the values from experimental tests. The course of computed displacements and stresses is similar to those obtained from experimental tests, although the absolute values were generally higher than the measured ones. Results of numerical analyses can be useful for bridge engineering, with particular regard to bridges and culverts made from corrugated steel plates for the range of necessity of using additional relieving elements.

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GEOLOGICAL AND GEOPHYSICAL CHARACTERISTICS OF THE ANABAR‐KHATANGA OIL AND GAS PROVINCE; NUMERICAL MODELING OF THE PROCESSES OF FORMATION OF SALT DOMES (SIBERIAN SECTOR OF THE RUSSIAN ARCTICS)

Geodynamics & Tectonophysics ◽

10.5800/gt-2019-10-2-0421 ◽

2019 ◽

Vol 10 (2) ◽

pp. 459-470

Author(s):

V. A. Kontorovich ◽

В. V. Lunev ◽

V. V. Lapkovsky

Keyword(s):

Cross Sections ◽

Oil And Gas ◽

Numerical Models ◽

Sedimentary Cover ◽

Ground Surface ◽

Geological Structure ◽

Salt Domes ◽

Software Packages ◽

Geological Features ◽

Gas Bearing

The article discusses the geological structure, oil‐and‐gas‐bearing capacities and salt tectogenesis of the Anabar‐Khatanga saddle located on the Laptev Sea shore. In the study area, the platform sediments are represented by the 14‐45 km thick Neoproterozoic‐Mesozoic sedimentary complexes. The regional cross‐sections show the early and middle Devonian salt‐bearing strata and associated salt domes in the sedimentary cover, which may be indicative of potential hydrocarbon‐containing structures. Diapirs reaching the ground surface can be associated with structures capable of trapping hydrocarbons, and typical anticline structures can occur above the domes buried beneath the sediments. In our study, we used the algorithms and software packages developed by A.A. Trofimuk Institute of Petroleum Geology and Geophysics (IPGG SB RAS). Taking into account the structural geological features of the study area, we conducted numerical simulation of the formation of salt dome structures. According to the numerical models, contrasting domes that reached the ground surface began to form in the early Permian and developed most intensely in the Mesozoic, and the buried diapirs developed mainly in the late Cretaceous and Cenozoic.

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Load bearing capacity of thin-walled rectangular and I-shaped steel sections of short both empty and concrete-filled columns

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.58.06 ◽

2021 ◽

Vol 15 (58) ◽

pp. 77-85

Author(s):

Amor Bouaricha ◽

Naoual Handel ◽

Aziza Boutouta ◽

Sarah Djouimaa

Keyword(s):

Cross Section ◽

Cross Sections ◽

Load Capacity ◽

Cross Sectional ◽

Short Columns ◽

Cross Section Area ◽

Section Area ◽

Specimen Height ◽

Steel Sections ◽

Thin Walled

In this experimental work, strength results obtained on short columns subjected to concentric loads are presented. The specimens used in the tests have made of cold-rolled, thin-walled steel. Twenty short columns of the same cross-section area and wall thickness have been tested as follows: 8 empty and 12 filled with ordinary concrete. In the aim to determine the column section geometry with the highest resistance, three different types of cross-sections have been compared: rectangular, I-shaped unreinforced and, reinforced with 100 mm spaced transversal links. The parameters studied are the specimen height and the cross-sectional steel geometry. The registered experimental results have been compared to the ultimate loads intended by Eurocode 3 for empty columns and by Eurocode 4 for compound columns. These results showed that a concrete-filled composite column had improved strength compared to the empty case. Among the three cross-section types, it has been found that I-section reinforced is the most resistant than the other two sections. Moreover, the load capacity and mode of failure have been influenced by the height of the column. Also, it had noted that the experimental strengths of the tested columns don’t agree well with the EC3 and EC4 results.

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