scholarly journals Bending and Shear Experimental Tests and Numerical Analysis of Composite Slabs Made Up of Lightweight Concrete

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
F. P. Alvarez Rabanal ◽  
J. Guerrero-Muñoz ◽  
M. Alonso-Martinez ◽  
J. E. Martinez-Martinez
Keyword(s):  
Numerical Simulations ◽  
Lightweight Concrete ◽  
Numerical Models ◽  
Experimental Studies ◽  
Experimental Tests ◽  
Isotropic Hardening ◽  
Structural Behaviour ◽  
Composite Slabs ◽  
The Coefficient Of Friction ◽  
Materials Used

The aim of this paper is to understand the structural behaviour of composite slabs. These composite slabs are made of steel and different kinds of concrete. The methodology used in this paper combines experimental studies with advanced techniques of numerical simulations. In this paper, four types of concrete were used in order to study their different structural strengths in composite slabs. The materials used were three lightweight concretes, a normal concrete, and a cold conformed steel deck which has embossments to increase the adherence between concrete and steel. Furthermore, two lengths of slabs were studied to compare structural behaviours between short and long slabs. m-k experimental tests were carried out to obtain the flexural behaviour of the composite slabs. These tests provide dimensionless coefficients to compare different sizes of slabs. Nonlinear numerical simulations were performed by means of the finite element method (FEM). Four different multilinear isotropic hardening laws were used to simulate the four concretes. Coulomb friction contact was used to model the coefficient of friction between steel and concrete. Finally, a chemical bond was included to consider sliding resistance in the contact surface between steel and concrete. Experimental and numerical results are in good agreement; therefore, numerical models can be used to improve and optimize lightweight composite slabs.

scholarly journals Thermal Inertia Characterization of Multilayer Lightweight Walls: Numerical Analysis and Experimental Validation

2021 ◽  
Vol 11 (11) ◽  
pp. 5008
Author(s):  
Juan José del Coz-Díaz ◽  
Felipe Pedro Álvarez-Rabanal ◽  
Mar Alonso-Martínez ◽  
Juan Enrique Martínez-Martínez
Keyword(s):  
Lightweight Concrete ◽  
Thermal Flux ◽  
Experimental Studies ◽  
Thermal Inertia ◽  
Transient State ◽  
Experimental Tests ◽  
Building Design ◽  
Experimental Methodology ◽  
Improve Energy Efficiency ◽  
Concrete Blocks

The thermal inertia properties of construction elements have gained a great deal of importance in building design over the last few years. Many investigations have shown that this is the key factor to improve energy efficiency and obtain optimal comfort conditions in buildings. However, experimental tests are expensive and time consuming and the development of new products requires shorter analysis times. In this sense, the goal of this research is to analyze the thermal behavior of a wall made up of lightweight concrete blocks covered with layers of insulating materials in steady- and transient-state conditions. For this, numerical and experimental studies were done, taking outdoor temperature and relative humidity as a function of time into account. Furthermore, multi-criteria optimization based on the design of the experimental methodology is used to minimize errors in thermal material properties and to understand the main parameters that influence the numerical simulation of thermal inertia. Numerical Finite Element Models (FEM) will take conduction, convection and radiation phenomena in the recesses of lightweight concrete blocks into account, as well as the film conditions established in the UNE-EN ISO 6946 standard. Finally, the numerical ISO-13786 standard and the experimental results are compared in terms of wall thermal transmittance, thermal flux, and temperature evolution, as well as the dynamic thermal inertia parameters, showing a good agreement in some cases, allowing builders, architects, and engineers to develop new construction elements in a short time with the new proposed methodology.

Numerical Testing and Validation of LVI on Composite Plates

2019 ◽  
Vol 957 ◽  
pp. 358-365
Author(s):  
Giuseppe Lamanna ◽  
Francesco Caputo
Keyword(s):  
Residual Life ◽  
Numerical Models ◽  
Laminated Composite ◽  
Composite Plates ◽  
Experimental Tests ◽  
Numerical Code ◽  
Experimental Comparison ◽  
Structural Behaviour ◽  
Numerical Tests ◽  
Impact Energies

Laminated composite plates are widely used in the aerospace field, the prediction of their residual life is a interesting challenge for research communities. Their structural behaviour could be affected by several rupture mechanisms due to exercise loading conditions. One of the most critical is the low velocities impacts with different impact energies. This paper deals with an experimental test program performed in order to validate a numerical model developed by using finite element method. All experimental tests were carried out under international standard ASTM D7136 while all numerical tests were carried out by use of a worldwide numerical code Abaqus®. Inter-laminar and intra-laminar rupture mechanisms were taken into account and special-purpose elements were used. Rupture criteria were implemented in the numerical models thanks to their functional ease; results of numerical-experimental comparison were presented and discussed.

Evaluation of numerical pounding models with experimental validation

2013 ◽  
Vol 46 (3) ◽  
pp. 117-130 ◽  
Author(s):  
S. Khatiwada ◽  
N. Chouw ◽  
J.W. Butterworth
Keyword(s):  
Numerical Simulations ◽  
Numerical Models ◽  
Experimental Studies ◽  
Viscoelastic Model ◽  
The Other ◽  
Analytical Models ◽  
Seismic Gap ◽  
Shake Table ◽  
Linear Viscoelastic ◽  
Linear Viscoelastic Model

Pounding damage in major earthquakes has been observed frequently in the form of aesthetic, minor or major structural cracks and collapse of buildings. These observations have attracted many numerical and experimental studies that led to analytical models for simulating seismic pounding. This study considers pounding between two steel portal frames without a seismic gap. The first frame has a constant natural period while the second frame has variable stiffness and mass values. Five different ground motions are applied to eight combinations of adjacent frames using a shake table. Numerical simulations for the same configurations are carried out with five pounding force models, viz. linear viscoelastic model, modified linear viscoelastic model, nonlinear viscoelastic model, Hertzdamp model and modified Hertzdamp model. The contact element stiffness and coefficient of restitution for numerical models are determined experimentally. The amplification of maximum displacement of the first frame predicted by the numerical simulations is compared with the shake table results. It was found that the Hertzdamp model always overestimated the responses while the other four models also frequently overestimated the amplifications. The predictions from the four models were not significantly different. Since the linear viscoelastic model requires substantially less computation, compared with the other models this model is more suitable for numerical modelling of pounding responses. However, more study is required to refine the numerical models before building pounding can be modelled with enough confidence.

scholarly journals Estimation of friction contribution in the behavior of steel-concrete composite beams with flexible shear connectors

2014 ◽  
Vol 67 (3) ◽  
pp. 253-258 ◽  
Author(s):  
Gilson Queiroz ◽  
Hermes Carvalho ◽  
Francisco Rodrigues ◽  
Michèle Pfeilo
Keyword(s):  
Composite Beam ◽  
Numerical Models ◽  
Experimental Tests ◽  
Composite Beams ◽  
Shear Connector ◽  
Limit States ◽  
Shear Connectors ◽  
Composite Slabs ◽  
Strength And Stiffness ◽  
Ultimate Limit

A shear connector, developed to be applied to a composite beam whose steel profile is a thin-walled box profile, displayed much greater flexibility than the conventional welded shear connector, leading to particular issues in the composite beam behaviour. One of these issues is the role played by friction at the interface between the steel profile and the slab which, under particular circumstances, may be relevant for serviceability limit states and also for ultimate limit states. The Brazilian and American Standards do not yet recognize the friction contribution in the behaviour of composite beams, though they recognize this contribution in composite slabs. This paper presents the experimental tests carried out with and without friction contribution on simple supported composite beams with flexible connectors and the numerical models developed to simulate the behaviour of the tested beams. The experimental tests revealed significant increases in strength and stiffness of the composite beam due to friction contribution and the comparisons between numerical and experimental results displayed good correlations.

Numerical Analysis of Masonry Confined by FRCM

2017 ◽  
Vol 747 ◽  
pp. 558-566 ◽  
Author(s):  
Francesco Saverio Murgo ◽  
Claudio Mazzotti
Keyword(s):  
Numerical Model ◽  
Numerical Models ◽  
Experimental Tests ◽  
Numerical Approach ◽  
Structural Behaviour ◽  
Confined Masonry ◽  
Axial Forces ◽  
Commercial Code ◽  
The University ◽  
Model Approach

In the present paper, structural behaviour of masonry columns strengthened with fiber reinforced cementitious matrix have been investigated; in particular, numerical 3D simulations calibrated on experimental tests have been presented. T hree-dimensional numerical model, realized by using the commercial code MIDAS FEA, based on a macro-model approach, has been used to simulate the nonlinear structural behavior of masonry columns strengthened with FRCM, and two different models for unreinforced and strengthened columns have been adopted. The 3D numerical approach are presented and results discussed to investigate the interaction between masonry columns and reinforcement. The numerical model has been calibrated on a large number of experimental tests on confined masonry columns carried out at the University of Bologna; in particular, columns have been wrapped by FRP and FRCM and with different arrangements (continuous and discontinuous). The comparison of the numerical models with the experimental outcomes shows a good matching in terms of axial forces-strain curves and strength peak.

scholarly journals Behavior of Beam-to-Column Connections with Angles. Part 2-Numerical Analysis

2016 ◽  
Vol 6 (1) ◽  
pp. 35-40
Author(s):  
M. Ghindea ◽  
A. Cătărig ◽  
R. Ballok
Keyword(s):  
Numerical Simulations ◽  
Deformation Process ◽  
High Speed ◽  
Rotation Curve ◽  
Numerical Models ◽  
Experimental Tests ◽  
3D Models ◽  
Experimental Investigations ◽  
Software Packages ◽  
Parametric Studies

Abstract Based on the results of experimental tests, presented in the first part of this paper, Part 1-Experimental Investigations (Ghindea M., Catarig A., Ballok R.) advanced numerical simulations were performed using FEM based software Abaqus. The recently arise of high speed computers and advanced FEM software packages allow to create and solve extensively detailed 3D models. The aim of this second part of the paper is to develop accurate FEM models for better approach of the studied beam-to-column connections. The paper presents the designed numerical models and the results for four bolted beam-to-column connections using top-and-seat and/or web angle cleats, in different configurations. The objective of this paper is to achieve functional numerical models which, by faithfully running, reproduce the experimental results. Thus, calibrating the numerical results with the experimental ones it can be perform then parametric studies, achieving reliable results for similar configurations of joints. The results obtained after numerical simulations were compared with experimental data. The behavior moment-rotation curve and the deformation process of the experimental captured specimens were virtually reproduced with minimum deviation.

Numerical and Experimental Studies on Impact Loaded Concrete Structures

2006 ◽  
Author(s):  
Arja Saarenheimo ◽  
Ilkka Hakola ◽  
Tuomo Ka¨rna¨ ◽  
Juhani Hyva¨rinen ◽  
Markku Tuomala
Keyword(s):  
Plastic Material ◽  
Numerical Models ◽  
Experimental Studies ◽  
Concrete Structures ◽  
Time History ◽  
Fuel Loading ◽  
Structural Behaviour ◽  
Fe Method ◽  
Rigid Plastic ◽  
The Impact

An experimental set-up has been constructed for medium scale impact tests. The main objective of this effort is to provide data for the calibration and verification of numerical models of a loading scenario where an aircraft impacts against a nuclear power plant. One goal is to develop and take in use numerical methods for predicting response of reinforced concrete structures to impacts of deformable projectiles that may contain combustible liquid (“fuel”). Loading, structural behaviour, like collapsing mechanism and the damage grade, will be predicted by simple analytical methods and using non-linear FE-method. In the so-called Riera method the behavior of the missile material is assumed to be rigid plastic or rigid visco-plastic. Using elastic plastic and elastic visco-plastic material models calculations are carried out by ABAQUS/Explicit finite element code, assuming axisymmetric deformation mode for the missile. With both methods, typically, the impact force time history, the velocity of the missile rear end and the missile shortening during the impact were recorded for comparisons.

scholarly journals Vision-Based Approach in Contact Modelling between the Footpad of the Lander and the Analogue Representing Surface of Phobos

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7009
Author(s):  
Marek Cała ◽  
Piotr Kohut ◽  
Krzysztof Holak ◽  
Daniel Wałach
Keyword(s):  
Numerical Models ◽  
Experimental Studies ◽  
Experimental Tests ◽  
Microgravity Environment ◽  
3D Vision ◽  
Foot Model ◽  
Celestial Bodies ◽  
Measured Deformation ◽  
2D And 3D ◽  
Single Material

Identifying solar system surface properties of celestial bodies requires the conducting of many tests and experiments in conditions similar to those found on various objects. One of the first tasks to be solved by engineers is determining the contact condition between the lander and the surface of a given celestial body during landing in a microgravity environment. This paper presents the results of experimental studies and numerical simulations of the contact phenomenon between the lander foot model and the Phobos analogue. The main goal of the experimental tests was to obtain measured deformation data of the studied analogues using 2D and 3D vision systems, which were employed to analyze the behavior of the lander foot and the surface of the studied analogue itself and to calibrate the numerical models. The analogue representing the Phobos surface was foam concrete. The variable parameters in the study were the analogue thickness and the lander foot velocity at the time of contact. Tests were conducted for three different contact velocities of 1.2 m/s, 3.0 m/s, and 3.5 m/s. Taking into account the mass of the lander foot model, kinetic energies of 30.28 J, 189.22 J, and 257.56 J were obtained. The results showed that at low contact velocities, and thus low kinetic energies, no significant differences in behavior of the material directly under the lander foot were observed, and similar values of forces in the lander foot were obtained. For higher contact velocities, the behavior of analogues with varying thicknesses was different, resulting in different values of analogue deformation and dynamics of increments and decrements of force in the lander foot itself. Although performed on a single material, the experiments revealed different behaviors depending on its thickness at the same impact energy. This is an essential guideline for engineers who need to take this fact into account when designing the lander itself.

scholarly journals DIC in Validation of Boundary Conditions of Numerical Model of Reinforced Concrete Beams Under Torsion

2018 ◽  
Vol 64 (4) ◽  
pp. 31-48 ◽  
Author(s):  
B. Turoń ◽  
D. Ziaja ◽  
L. Buda-Ożóg ◽  
B. Miller
Keyword(s):  
Reinforced Concrete ◽  
Numerical Model ◽  
Boundary Conditions ◽  
Numerical Simulations ◽  
Experimental Research ◽  
Concrete Beams ◽  
Numerical Models ◽  
Experimental Tests ◽  
Reinforced Concrete Beams ◽  
Image Correlation

AbstractThe paper presents the experimental research and numerical simulations of reinforced concrete beams under torsional load. In the experimental tests Digital Image Correlation System (DIC System) Q-450 were used. DIC is a non-contact full-field image analysis method, based on grey value digital images that can determine displacements and strains of an object under load. Numerical simulations of the investigated beams were performed by using the ATENA 3D – Studio program. Creation of numerical models of reinforced concrete elements under torsion was complicated due to difficulties in modelling of real boundary conditions of these elements. The experimental research using DIC can be extremely useful in creating correct numerical models of investigated elements. High accuracy and a wide spectrum of results obtained from experimental tests allow for the modification of the boundary conditions assumed in the numerical model, so that these conditions correspond to the real fixing of the element during the tests.

scholarly journals Numerical calculations of behaviour of ship double-bottom structure during grounding

2008 ◽  
Vol 15 (Special) ◽  
pp. 22-26 ◽  
Author(s):  
Karol Niklas
Keyword(s):  
Numerical Model ◽  
Numerical Simulations ◽  
Numerical Models ◽  
Experimental Tests ◽  
Numerical Calculations ◽  
Polymer Concrete ◽  
Design Work ◽  
Ship Structure

Numerical calculations of behaviour of ship double-bottom structure during grounding The idea of the CORET project consists in adding, to the existing construction, special polymer-concrete coatings intended for the increasing of ship's capability against losing structural tightness during collision or grounding. In order to correctly design the protective barriers, to perform relevant numerical simulations is necessary. The elaborating of numerical models of ship structure behaviour during collision is very complicated and requires auxiliary simulations (on submodels) to be performed. This paper is devoted to elaborating a numerical model of a fragment of ship double-bottom structure. On the basis of experimental tests it was possible to verify and calibrate the numerical model which may be used in further design work aimed at the increasing of crashworthiness of structure during collision.

Sign in / Sign up

Export Citation Format

Share Document