Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : FEM

Nonlinear 3D Finite Element Model for Round Composite Columns under Various Eccentricity Loads

Dara A. Mawlood; Serwan K. Rafiq

Engineering and Technology Journal, 2022, Volume 40, Issue 11, Pages 1605-1614
DOI: 10.30684/etj.2022.133106.1168

Composite columns are often used in constructing high-rise structures because they can reduce the size of a building's columns while increasing the usable area in the floor plan. This research aimed to develop a nonlinear 3D finite element analysis model using the ABAQUS, version 6.13-4, of various round composite column designs with varied multi-skin of tubes for solid and hollow columns subjected to various eccentricity loads (90, 180 mm). Extended data to another 12 specimens of composite columns by numerical method, based on six references experimental data of composite columns. The results of ABAQUS data in this study show that; increasing eccentricity for applied loads causes a decrease in loads to fail for composed columns. The ultimate load of hollow composite sections under eccentricity is lower than solid composite sections under different eccentricity loads. Also, the same results indicated fort eccentricity loads. The same results indicated an increased number of steel layers. The stiffness of concrete is greatly influenced by its strength. When the concrete strength rises, the stiffness of the composite column rises as well. The ratios of concrete compressive strength values according to the reference column (CC1S00 with fc’=31.96 MPa) were (-4.4, 3.1, and 6.5) percent for the specimen (CC1S00) with (fc’=25, 35, and 40) MPa, respectively. The method utilized is in the nonlinear analysis, and the finite element results are in good agreement with the experimental results.

Experimental Study and Numerical Simulation of Plane Steel Frame with Rubberized Connecting Technology Subjected to Seismic Effect

Suhaib J. Ali; Amer M. Ibrahim; Sarmad Shafeeq

Engineering and Technology Journal, 2021, Volume 39, Issue 3A, Pages 415-425
DOI: 10.30684/etj.v39i3A.1500

This paper represents experimental and numerical study the behavior of the rubberized steel frame connections. One single-bay, one-story without elastic buckling are cyclically tested. The experimental specimens are simulated and analyzed by the ABAQUS program. Four specimens of steel plane portal frame are investigated under horizontal reversed cyclic loads. The specimen connections are developed by using different diameters of composite steel bolts/rubber instead of conventional steel bolts to connect the beams with columns. The yield and ultimate strength, ductility, envelope curves, and damping ratio of these specimens are analyzed and compared. The finite element method is used to establish and verify the results of the laboratory test. The results of the experimental and numerical tests gave a large load-carrying capacity, reduction in the stresses, excellent ductility and energy dissipation capacity, and remarkably improved damping ratio.

Experimental and Simulation Study the Effect of Different Reduction Ratios in Cold Rolling Process on the Residual Stresses of AL 2024 Alloy

Samir Ali Amin Al-Rabii; Sadiq Jaffar Aziz; Ali Hussein Alwan

Engineering and Technology Journal, 2015, Volume 33, Issue 5, Pages 1049-1064

Cold forming processes are the common processes in sheet metal forming, especially in the final stages of production processes. In this work, cold rolling process was selected to study the effect of different reduction ratios on the residual stresses state in aluminum alloy (2024). Sheets of aluminum alloy (2024-T3) were prepared with dimensions (400 X 80 X 3.15 mm).The annealing process was conducted for these sheets to get the temper condition (2024-O). The cold rolling process was performed with different reduction ratios (10%, 20%, 30%, 40%, 50%, 60%) by a rolling machine composed of two rolls having (50 mm) diameter each.The residual stresses were measured using X-ray diffraction technique (XRD) in two directions (rolling direction RD, and transverse direction TD).The results of X-ray diffraction showed the presence of residual stresses at the surface of rolled specimens, and these were compressive stresses in the two tested directions (RD, and TD) at 10% reduction ratio. When the reduction ratio exceeded 10%, these stresses transformed to tensile stresses for specimens tested in rolling direction, while these stresses remained compressive type for all reduction ratios in transverse direction.Computer simulation was carried out using finite element method (FEM) by (ANSYS-LSDYNA 12.1) software to investigate the residual stresses behavior of AA 2024. The numerical results showed a good agreement with the experimental resultsespecially for samples tested in the rolling direction.

Fe Analysis of Residual Stresses Induced by Spot Welding of Stainless Steel Type Aisi 316

Ahmed N. Al-Khazraji; Samir A. Al-Rabii; Ali Hussein F. Al-Jelehawy

Engineering and Technology Journal, 2014, Volume 32, Issue 2, Pages 365-384
DOI: 10.30684/etj.32.2A.7

Specimens of the as-received stainless steel type 316, according to AISI standard, in form of sheet with 1.5 mm thickness were first spot welded and thenshot peened to obtain the influence of shot peening process on the residual stresses induced by spot welding process. X-Ray Diffraction (XRD) method was used to measure the residual stresses. Also, a finite element method (FEM) was employed by ANSYS software version 11 to achieve the simulations for transient thermal analysis and residual stresses analysis in all cases. In addition, the temperature dependency of materials properties was used to assess its effects on the final residual stress results. A comparison showed a very good agreement between the experimental and the numerical results due to the total elimination of tensile residual stresses and creating the compressive type instead.

Numerical and Experimental Investigation of Plate Buckling under In-plane Loading

Naseer Hamed Farhood

Engineering and Technology Journal, 2012, Volume 30, Issue 20, Pages 3506-3523
DOI: 10.30684/etj.30.20.3

The objective of this work is to predict the plate elastic buckling includes
critical buckling load and corresponding buckling mode for stiffened and unstiffened
plate under in-plane loading. The numerical study has been achieved by
employing the FEM (ANSYS package ver.11) using a shell element of eight nodes
with five DOF at each node as a discretization element such that the equation of
elastic stability with isotropic material properties has been taken into consideration
The study of aluminum alloy 6063-O plates subjected to in-plane loading showing
the effect of stiffened plates, stepped thickness, and changing of applied loading. It
has been found that buckling strength increases when plate width (b) increase for
stiffened and unstiffened plate, also critical buckling load has high values for
biaxial load than uniaxial for plates with the same specification. Also, an
experimental test has been performed on different cases which exhibit a good
verification of results.

Finite Element Modeling and Simulation of Orthogonal Cutting With Multi Layer Coated Tools

Maan Aabid Tawfiq; Zeena jumaa Ahmed

Engineering and Technology Journal, 2008, Volume 26, Issue 7, Pages 829-841

This paper focuses on the development of Finite Element Method (FEM) in
modeling and simulation of coated cutting tools with multi-layer coats. A special Finite
Element code called (MSC.MARC mentat) is used in the numerical tests, the results are
then compared with experimental work. The paper studied the effect of number of coats
of cutting tools on the following field parameters; tool-chip contact length, chip
contraction coefficient and shear angle at similar machining conditions.The metal being
machined is (AISI 1045 steel) with orthogonal machining conditions. The three cutting
tools and models are coated with (TiN, TiN/TiC, TiN/Al2O3/TiC), while the fourth one
is uncoated.The results show good agreement between the experimental and numerical
tests. Some of the results are compared with other published papers. The comparison of
the predicted results shows good agreement with experimental tests with maximum
relative difference of (18%) for the chip contraction coefficient and contact length, and
(10 %) for the shear angle. The insert with double coats shows excellent result,
compared to others from point of view of chip contraction coefficient, contact length and
shear angle.