The original source code can be found on Github .

What is Aladdin?

Aladdin is a computational toolkit for the interactive matrix and finite element analysis of large engineering structures, particularly building and highway bridge structures. Aladdin views finite element computations as a specialized form of matrix computations, matrices as rectangular arrays of physical quantities, and numbers as dimensionless physical quantities.

Aladdin Version 1.0 , released in May 1996, provides engineers with:

• Mechanisms to define physical quantities with units, and matrices of physical quantities.
• Facilities for physical quantity and matrix arithmetic.
• A SI and US units package. Conversion of units may be applied to physical quantity constants, physical quantity variables, and matrices of physical quantities.
• A matrix package. Its capabilities include matrix arithmetic, solution of linear matrix equations, and the general symmetric eigenvalue problem.
• Programming constructs to control the solution procedure (i.e., branching and looping) in matrix and finite element problems.
• A finite element mesh generation package. Two- and three-dimensional finite element meshes can be created.
• A library of finite elements. Currently, the finite element library includes elements for plane stress/plane strain analysis, two-dimensional beam/column analysis, three-dimensional truss analysis, DKQ plate analysis, and a variety of shell finite elements.

Aladdin Version 2.1 , released in March 2000, contains a variety of new features for nonlinear analysis of structures with fiber finite elements.

Aladdin Version 3.0 is in the early stages of development. We are currently working on finite elements and numerical algorithms for the analysis of structures undergoing large geometric displacements, and problems involving fluid flow and fluid-structure interaction . In a second project we are developing a suite of numerical algorithms for the hybrid control of large structural systems.

Applications : We are using Versions 2 and 3 of Aladdin for the performance-based design and analysis of base-isolated highway bridge structures and tethered aerostat systems.

Basic Features

Aladdin's problem solving capabilities include:

• Getting Started :
  • Aladdin Architecture
  • Modes of Program Input and Output
• Command Language :
  • Language Format and Data Types
  • Keywords and Builtin Constants
  • Printing Strings
• Quantities :
  • Definition and Printing of Quantities
  • Arithmetic
  • Math Functions
• Constructs for Program Control :
  • Logical and Relational Expressions
  • Branching Constructs
  • Looping Constructs

Matrices

• Getting Started :
  • Definition and Printing of Matrices
  • Matrix Arithmetic
  • Matrix Operations
  • Linear Equations [A].[x] = [b]
  • Eigenvalues and Eigenvectors
• Linear Structural Analysis and Mechanics :
  • Modal Analysis of 4 Story Shear Building
  • Elastic Buckling of a Pin-Ended Column
  • Eigenvalue Analysis of a Cantilever Beam with End Support
• Nonlinear Structural Analysis :
  • Force-Displacement Response of Material Softening Composite Bar
  • Force-Displacement Response of Nonlinear Mass-Spring System
• Structural Dynamics and Earthquake Analysis :
  • Earthquake Response Spectrum Analysis of 4 Story Shear Building

For more information on these examples, download the Aladdin Technical Research Reports TR95-74 and TR95-104.

Click here for a "Tutorial Introduction to Aladdin" that's in a printable format.

Finite Elements

• Getting Started :
  • Finite Element Input Files
  • Library of Finite Elements
  • Mesh Generation
  • Problem Solving Procedures
• Linear Structural Analysis and Mechanics :
  • Structural Analysis of Three-Span Beam Structure
  • Structural Analysis of Moment-Resistant Frame
  • Plane Stress Analysis of Cantilever
  • Plane Strain Analysis of Pipe Cross Section
  • Analysis of Shear Loaded Cantilever Beam
  • Analysis of Cantilever I-Beam
  • Analysis of Five Story Moment Resistant Frame
• Nonlinear Structural Analysis and Mechanics :
  • Rectangular Plate subjected to Uniaxial Loading
  • Force-Displacement Response of Cantilever with Material Nonlinearity
• Linear Analysis of Highway Bridge Structures :
  • Simplified Working Stress Design of a One-Span Highway Bridge
  • Three-Dimensional Analysis of a Continuous Two-Span Highway Bridge
• Nonlinear Behavior of Lead-Rubber Isolation Devices :
  • Behavior of Lead-Rubber Isolator under Cyclic Shear Loadings
• Structural Dynamics and Earthquake Analysis :
  • Linear Time-history Analysis of 5 Story Steel Building
  • Three-Dimensional Dynamic Response of Pier Structure.
  • Dynamic Analysis of a Base-Isolated Highway Bridge Structure
• Large Geometric Displacements :
  • Rollup Maneuver for Long Cantilever Beam
  • Force-Controlled Maneuver of a Flexible Robot Arm

For more information on these examples, download the Aladdin Technical Research Reports TR95-74 and TR95-104.

Extensions to Aladdin

• How to add a Matrix Function to Aladdin
• How to add a Finite Element to Aladdin

• Michele De Lorenzi (Ph.D. student in Italy) has created a Tk Interface to simulate Aladdin in interactive mode.

Publications

• Austin M.A., and Sebastianelli R., Phase Analysis of Actuator Response for Sub-Optimal Bang-Bang and Velocity Cancellation Control of Base Isolated Structures, Journal of Structural Control and Health Monitoring , Vol. 14, Issue 7, July 2007, pp. 1034-1061.

• Sebastianelli R. and Austin M.A., Energy Balance and Power Demand Assessment of Actuators in Base Isolated Structures supplemented with Modified Bang-Bang Control, Structural Engineering and Mechanics , Vol. 25, No. 5, March 2007, pp. 541-564.

• Austin M.A., Matrix and Finite Element Stack Machines for Structural Engineering Computations with Units, Advances in Engineering Software, Elsevier, Vol. 37, No. 8, August 2006, pp. 544-559.

• Austin M.A. and Lin W.J., Energy-Balance Assessment of Isolated Structures, Journal of Engineering Mechanics, ASCE, Vol. 130, No. 3, March 2004, pp. 347-358.

• Austin M.A., Lin W.J., and Chen X.G., Structural Matrix Computations with Units, Journal of Computing in Civil Engineering , ASCE, Vol. 14, No. 3, July 2000, pp. 174-182.

• Austin M.A., Lin W.J., and Chen X.G., Structural Matrix Computations with Units: Data Structures, Algorithms, and Scripting Language Design, ISR Technical Report 99-63 ( ps.gz , 406 KB) ( pdf , 392 KB), University of Maryland, College Park, MD 20742, November, 1999, 39 p.

• Austin M.A. and Chancogne D., Introduction to Engineering Programming : in C, MATLAB, and JAVA , John Wiley and Sons, New York, December 1998, (p. 656). Note - The C tutorial contains a simplified explanation of how the dynamic allocation of matrices works in Aladdin.

• Lin W.J. and Austin M.A., Design of a Scripting Language for the Energy-Based Analysis of Nonlinear Structural Systems ( ps.gz ,273 KB), I3th U.S. National Congress of Applied Mechanics, University of Florida, Gainesville, June 21-26, 1998.

• Lin W.J., Modern Computational Environments for Seismic Analysis of Highway Bridge Structures ( ps.Z , 805 KB), Ph.D. Dissertation, University of Maryland, College Park, MD 20742, December 1997, (p. 197). Note - Wane-Jang's dissertation describes a lot of the new features in Aladdin 2.0.

• Austin M.A., Chen X.G., and Lin W.J., Aladdin: A Computational Toolkit for Interactive Engineering Matrix and Finite Element Analysis, ISR Technical Research Report TR95-74 ( ps ) ( pdf ), University of Maryland, College Park, MD 20742, August 1995, (p. 235). Click here for the Table of Contents to TR95-74.

• Chen X.G. and Austin M.A., A Systems Approach to Nonlinear Finite Element Analysis of Shell Structures, ISR Technical Research Report TR95-104 ( ps.Z , 346 KB), University of Maryland, College Park, MD 20742, December 1995, (p. 57).

• Lanheng Jin, Analysis and Evaluation of a Shell Finite Element with Drilling Degree of Freedom, ISR Masters Thesis Report M.S. 94-12 ( ps.Z , 331 KB) ( pdf , 401 KB), Institute for Systems Research, University of Maryland, College Park, MD 20742, December 1994, (p. 60).

Aladdin Source Code

At this time, versions 1.0 and 2.1 of the Aladdin source code are available. Version 2.1 is approximately 40,000 lines of C.

• Software Portability : Aladdin has been tested on a SUN SPARCstation, DECstation 5000, IBM RS/6000 and Linux. Click here for details on how to compile windows versions of Aladdin using DJGPP (with bison & flex utility available from www.delorie.com) and Visual C++ 6.0.
  
  
• Downloading the Software : To obtain a copy of the source code to Aladdin 2.1, please complete the registration form , and click on the appropriate links.
  
  
• Copyright Notice : Distribution and use of this software is subject to the conditions set forth in the "copyright notice." Please read and agree to these terms before using the software.
  
  
• Software Limitations : Check out the what's new page for a list of recently added features and release dates. Click here for a list of software limitations and bugs that we know about, but haven't had time to fix.

Acknowledgements

Aladdin is being developed at the Institute for Systems Research, University of Maryland, College Park, USA, under the financial sponsorship of the Federal Highway Administration and the National Science Foundation.

Versions 1 and 2 of Aladdin were written by Mark Austin , Wane-Jang Lin, and Xiaoguang Chen.

Drafts of the plane stress/plain strain examples were developed by Clara Popescu. The four node shell finite element and associated examples were developed by Lanheng Jin.