Thứ Ba, 15 tháng 1, 2019

Resources for Computational mechanics of structures and materials


Open source codes

·         eXtended Finite Element Method (XFEM) in Matlab (4465 downloads). link.

·         eXtended Finite Element Method (XFEM) in C++ (1891 downloads). link.

·         Element Free Galerkin Method (EFG) in Matlab (2086 downloads). link.

·         Isogeometric analysis for solids and structures in Matlab (12450 downloads). link.

·         Zero thickness interface element generators in C++ (975 downloads). link.

Research facilities

·         Software development kit for advanced numerical simulations (jem-jive). link.

·         Mesh generation--Gmsh

·         Visualisation--Paraview and VisIt.

·         Voronoi diagrams--Neper.

·         Material Point Method code in Matlab

·         FENICS: automating the finite element methods 

·         Symbolic algebra packages--Maple/SageMath.

·         From images to FE meshes: oof2.

·         Commercial codes: Abaqus, LS-DYna, Tecplot

·         Tool for coding: SublimeText, and XCode (for debugging and profiling) + iTerm2 (with zsh)

 

I have been using LaTeX for writing reasearch articles/reports/documents since 2003. I use Microsoft Word only for proposals. For presentation slides, I use Keynote and LaTeXIt (on Mac OS).

·         Document writing: LaTeX (TexShop+Flashmode, Texpad, and SublimeText)

·         Graphics: vector graphics with Adobe Illustrator or Inkscape.

·         Finding LaTeX codes for any symbols: detexify.

·         Make animated GIF images from videos/images: in Mac OS X, simply use GIF Brewery 3 (you might need to use Quick View to convert format of your videos first). In Linux, you can use ffmpeg.

·         Making tables with http://www.tablesgenerator.com.

 

Others

·         Blog of Prof Rebecca Brannon at Univerisity of Utah: excellent notes on mechanics .

·         imechanica: web for mechanics and mechanicians 

·         Excellent lecture notes of Prof Fellipa at Colorado: introduction to FEMnonlinear FEM, advanced FEM

·         MIT courses on computational science & engineering (Prof G Strang)

·         MIT course on waves and vibrations

·         MIT course on linear finite elements (Prof KJ Bathe)

·         MIT course on nonlinear finite elements

·         An online book on Computational physics

·         Learning Linux in 10 minutes

·         Tutorials on Abaqus

·         http://www.parresianz.com/index.html (with useful info on computational modelling)


(Source: http://nvinhphu.wixsite.com/mysite/resources)

Thứ Sáu, 11 tháng 1, 2019

Abaqus2Matlab v2.0

A novel software is presented to connect Abaqus, a sophisticated finite element package, with Matlab, the most comprehensive program for mathematical analysis.
 
This interface between these well-known codes not only bene fits from the image processing and the integrated graph-plotting features of Matlab, but opens up new opportunities in results post-processing, statistical analysis and mathematical optimization, among many other possibilities.​
Abaqus2Matlab is freely distributed as source code with the aim of facilitating research
Main page: here
Online help: here
Tutorial:

Thứ Hai, 7 tháng 1, 2019

Wave-Seabed-Structure Interactions

Jeng 2013_Porous Models for Wave-seabed Interactions


Jeng 2019_Mechanics of Wave-Seabed-Structure Interactions


PhD Thesis - Modelling and analysis of Wave-structure-foundation interaction for Monolithic Breakwaters-Diss_Elsafti Hisham 2015

PhD Thesis - Modelling and analysis of Wave-structure-foundation interaction for Monolithic Breakwaters-Diss_Elsafti Hisham 2015



Dynamic characteristics of a sandy seabed under storm wave-principal stress rotation

Zhu 2019_Dynamic characteristics of a sandy seabed under storm wave-principal stress rotation


Li, Jeng (2019). Effects of Principal Stress Rotation on the Fluid-Induced Soil Response in a Porous Seabed.

Singapore cut and cover collapse

Reasons
• Method A over-es1mates the undrained shear strength of normally and lightly overconsolidated clays
• Its use led to a 50% under-es1mate of wall displacements and of bending moments and an under-estimate of the 9th level strut force of 10%


Finite Element Modelling using PLAXIS 2D

Finite Element Modelling using PLAXIS 2D

Thứ Bảy, 5 tháng 1, 2019

Some Applications of Soil Dynamics - 2009 Buchanan Lecture by Jose Roesse

https://ceprofs.civil.tamu.edu/briaud/lecture_series.html

The Spencer J. Buchanan Lecture Series on the GeoChannel is presented by the Geo-Institute of ASCE. For more information about the Geo-Institute: http://www.asce.org/geotechnical The 17th Spencer J. Buchanan Lecture in the Department of Civil Engineering at Texas A&M University was given by Jose M Roesset on Nov. 13, 2009.


"Some Applications of Soil Dynamics" Abstract: Soil Dynamics is the branch of Soil Mechanics (or in more fashionable modern terms Geotechnical Engineering) that studies the behavior of soil deposits and earth structures subjected to dynamic loads. It originated in the first quarter of the 20th century with the need to understand and eliminate the vibrations of foundations caused by heavy rotating machinery. It has become since an essential component of Earthquake Engineering (recognized even by some structural engineers), and it has found a number of other important practical applications. These include the determination of the dynamic stiffness of different types of foundations subjected to dynamic loads, the study of the effect of local soil conditions on the characteristics of earthquake motions, seismic soil structure interaction analyses, the seismic response of earth structures, the study of vibrations created by construction equipment, such as pile driving machines, or moving loads, and the determination of soil properties in laboratory tests and in situ. In this lecture we will look briefly at some of these applications, their historical background, the present state of the art and basic features of the problem, and some of the research needs. About Jose M Roesset: As a faculty member in the Civil Engineering Department of MIT (1964-1978) Dr Roesset conducted roughly half of his research on Nonlinear Structural Dynamics, with special emphasis on Earthquake Engineering, and the other half on what is known now as Geotechnical Earthquake Engineering. His structural work involved studies on inelastic response spectra, development of nonlinear structural models such as the fiber model, assessment of the validity of approximate procedures to derive equivalent inelastic single degree of freedom systems from incremental nonlinear static analyses of frames (later called the push-over method), and development of formulations in time and frequency domains. His work on geotechnical engineering involved first studies of the effect of local soil conditions on the characteristics of earthquake motions (soil amplification) for different types of seismic waves, then the determination of the dynamic stiffness of mat foundations and single piles, and finally the study of the effects of the soil/foundation flexibility on the seismic response of structures (soil structure interaction). Much of this work found applications in the seismic analysis and design of Nuclear Power Plants, a hot topic at that particular time, and Dr. Roesset served as a consultant in a number of plants. At the University of Texas at Austin (1978-1997) Dr. Roesset continued to do some work on nonlinear structural dynamics and on dynamic stiffness of foundations (pile groups in particular) but he devoted most of his research effort to more fundamental wave propagation studies with special application to the nondestructive evaluation of soil deposits and pavement systems. This work was performed in collaboration with Dr. Kenneth H. Stokoe (the sixteenth Buchanan lecturer) and involved on one hand the development of the formulation to interpret the data obtained with the Spectral Analysis of Surface Waves (SASW) method in order to backfigure the variation of soil properties with depth, and on the other the interpretation of the data obtained from Dynaflect and Falling Weight Deflectometer (FWD) tests to determined the elastic properties of pavement layers. The studies in this last case included the evaluation of the effects of the finite width of the pavement and the relative position of the FWD with respect to the edge, and the assessment of the importance of nonlinear soil behavior under large loads, particularly for flexible pavements. Video Extraction by Magnus Media Group: http://www.magnusmediagroup.com/