All structures suffer from stresses and strains caused by factors such as wind loading and vibrations. Stress analysis and measurement is an integral part of the design and management of structures, and is used in a wide range of engineering areas.
There are two main types of stress analyses the first is conceptual where the structure does not yet exist and the analyst has more freedom to define geometry, materials, loads etc generally such analysis is undertaken using numerical methods such as the finite element method. The second is where the structure (or a prototype) exists, and so some parameters are known. Others though, such as wind loading or environmental conditions will not be completely known and yet may profoundly affect the structure. These problems are generally handled by an ad hoc combination of experimental and analytical methods.
This book therefore tackles one of the most common challenges facing engineers how to solve a stress analysis problem when all of the required information is not available. Its central concern is to establish formal methods for including measurements as part of the complete analysis of such problems by presenting a new approach to the processing of experimental data and thus to experimentation itself. In addition, engineers using finite element methods will be able to extend the range of problems they can solve (and thereby the range of applications they can address) using the methods developed here.
Modern Experimental Stress Analysis:
Presents a comprehensive and modern reformulation of the approach to processing experimental dataOffers a large collection of problems ranging from static to dynamic, linear to non-linearCovers stress analysis with the finite element methodIncludes a wealth of documented experimental examplesProvides new ideas for researchers in computational mechanics
Preface.Notation.
Introduction.
1 Finite Element Methods.
1.1 Deformation and Strain.
1.2 Tractions and Stresses.
1.3 Governing Equations of Motion.
1.4 Material Behavior.
1.5 The Finite Element Method.
1.6 Some Finite Element Discretizations.
1.7 Dynamic Considerations.
1.8 Geometrically Nonlinear Problems.
1.9 Nonlinear Materials.
2 Experimental Methods.
2.1 Electrical Filter Circuits.
2.2 Digital Recording and Manipulation of Signals.
2.3 Electrical Resistance Strain Gages.
2.4 Strain Gage Circuits.
2.5 Motion and Force Transducers.
2.6 Digital Recording and Analysis of Images.
2.7 Moiré Analysis of Displacement.
2.8 Holographic Interferometry.
2.9 Photoelasticity.
3 Inverse Methods 171
3.1 Analysis of Experimental Data.
3.2 Parametric Modeling of Data.
3.3 Parameter Identification with Extrapolation.
3.4 Identification of Implicit Parameters.
3.5 Inverse Theory for Ill-Conditioned Problems.
3.6 Some Regularization Forms.
3.7 Relocation of Data onto a Grid Pattern.
3.8 Discussion.
4 Static Problems 219
4.1 Force Identification Problems.
4.2 Whole-Field Displacement Data.
4.3 Strain Gages.
4.4 Traction Distributions.
4.5 Nonlinear Data Relations.
4.6 Parameter Identification Problems.
4.7 Choosing the Parameterization.
4.8 Discussion.
5 Transient Problems with Time Data.
5.1 The Essential Difficulty.
5.2 Deconvolution using Sensitivity Responses.
5.3 Experimental Studies.
5.4 Scalability Issues: Recursive Formulation.
5.5 The One-Sided Hopkinson Bar.
5.6 Identifying Localized Stiffness and Mass.
5.7 Implicit Parameter Identification.
5.8 Force Location Problems.
5.9 Discussion.
6 Transient Problems with Space Data.
6.1 SpaceTime Deconvolution.
6.2 Preliminary Metrics.
6.3 Traction Distributions.
6.4 Dynamic Photoelasticity.
6.5 Identification Problems.
6.6 Force Location for a Shell Segment.
6.7 Discussion.
7 Nonlinear Problems.
7.1 Static Inverse Method.
7.2 Nonlinear Structural Dynamics.
7.3 Nonlinear Elastic Behavior.
7.4 Elastic-Plastic Materials.
7.5 Nonlinear Parameter Identification.
7.6 Dynamics of Cracks.
7.7 Highly Instrumented Structures.
7.8 Discussion.
Afterword.
References.
Index.