Browsing by Author "Jones, Robert M."
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- Accelerated viscoelastic characterization of T300/5208 graphite- epoxy laminatesTuttle, M. E. (Virginia Polytechnic Institute and State University, 1984)The viscoelastic response of polymer-based composite laminates, which may take years to develop in service, must be anticipated and accommodated at the design stage. Accelerated testing is therefore required to allow long-term compliance predictions for composite laminates of arbitrary layup, based solely upon short-term tests. In this study, an accelerated viscoelastic characterization scheme is applied to T300/5208 graphiteepoxy laminates. The viscoelastic response of unidirectional specimens is modeled using the theory developed by Schapery. The transient component of the viscoelastic creep compliance is assumed to follow a power law approximation. A recursive relationship is developed, based upon the Schapery single-integral equation, which allows approximation of a continuous time-varying uniaxial load using discrete steps in stress. The viscoelastic response of T300/5208 graphite-epoxy at 149C to transverse normal and shear stresses is determined using 90-deg and 10-deg off-axis tensile specimens, respectively. parameters In each case the seven viscoelastic material required in the analysis are determined experimentally, using a short-term creep/creep recovery testing cycle. A sensitivity analysis is used to select the appropriate short-term test cycle. It is shown that an accurate measure of the power law exponent is crucial for accurate long-term predictions, and that the calculated value of the power law exponent is very sensitive to slight experimental error in recovery data. Based upon this analysis, a 480/120 minute creep/creep recovery test cycle is selected, and the power law exponent is calculated using creep data. A short-term test cycle selection procedure is proposed, which should provide useful guidelines when other viscoelastic materials are being evaluated. Results from the short-term tests on unidirectional specimens are combined using classical lamination theory to provide long-term predictions for symmetric composite laminates. Experimental measurement of the long-term creep compliance at 149C of two distinct T300/5208 laminates is obtained. A reasonable comparison between theory and experiment is observed at time up to 10 5 minutes. Discrepancies which do exist are believed to be due to an insufficient modeling of biaxial stress interactions, to the accumulation of damage in the form of matrix cracks or voids, and/or to interlaminar shear deformations which may occur due to viscoelastic effects or damage accumulation.
- Analysis of reinforced embankments and foundations overlying soft soilsSchaefer, Vernon Ray (Virginia Polytechnic Institute and State University, 1987)The use of tensile reinforcement to increase the tensile strength and shear strength of soils has lead to many new applications of reinforced soil. The use of such reinforcing in embankments and foundations over weak soils is one of the most recent applications of this technology. The studies conducted were concerned with the development of and application of analytical techniques to reinforced soil foundations and embankments over weak soils. A finite element computer program was modified for application to reinforced soil structures, including consolidation behavior of the foundation soil. Plane strain and axisymmetric versions of the program were developed and a membrane element developed which has radial stiffness but no flexural stiffness. The applicability of the program was verified by comparing analytical results to case histories of reinforced embankments and to model studies of reinforced foundations. A simplified procedure for computing the bearing capacity of reinforced sand over weak clay was developed which is more general than those previously available. Good agreement with available experimental results was obtained, providing preliminary verification of the procedure. Extensive analyses were made of a reinforced embankment successfully constructed with no sign of distress, and of two reinforced embankments constructed to failure. These analyses showed that good agreement can be obtained between measured and calculated reinforcement forces, settlements, and pore pressures for both working and failure conditions. The analyses further show that the use of the finite element method and limit equilibrium analyses provide an effective approach for the design of reinforced embankments on weak foundations.
- Analysis of Tow-Placed, Variable-Stiffness LaminatesWaldhart, Chris (Virginia Tech, 1996-06-05)It is possible to create laminae that have spatially varying fiber orientation with a tow placement machine. A laminate which is composed of such plies will have stiffness properties which vary as a function of position. Previous work had modelled such variable-stiffness laminae by taking a reference fiber path and creating subsequent paths by shifting the reference path. This thesis introduces a method where subsequent paths are truly parallel to the reference fiber path. The primary manufacturing constraint considered in the analysis of variable-stiffness laminates was limits on fiber curvature which proved to be more restrictive for parallel fiber laminae than for shifted fiber. The in-plane responses of shifted and parallel fiber variable-stiffness laminates to either an applied uniform end shortening or in-plane shear were determined. Both shifted and parallel fiber variable-stiffness laminates can redistribute the applied load thereby increasing critical buckling loads compared to traditional straight fiber laminates. The primary differences between the two methods is that parallel fiber laminates are not able to redistribute the loading to the degree of the shifted fiber. This significantly reduces the increase in critical buckling load for parallel fiber variable-stiffness laminates over straight fiber laminates.
- Automated design of composite plates for improved damage toleranceGürdal, Zafer (Virginia Polytechnic Institute and State University, 1985)An automated procedure for designing minimum-weight composite plates subject to a local damage constraint under tensile and compressive loadings has been developed. A strain based criterion was used to obtain fracture toughness of cracked plates under tension. Results of an experimental investigation of the effects of simulated through-the-thickness cracks on the buckling, postbuckling, and failure characteristics of composite flat plates are presented. A model for kinking failure of fibers at the crack tip was developed - for compression loadings. A finite element program based on linear elastic fracture mechanics for calculating stress intensity factor (SIF) was incorporated in the design cycle. A general purpose mathematical optimization algorithm was used for the weight minimization. Analytical sensitivity derivatives of the SIF, obtained by employing the adjoint variable technique, were used to enhance the computational efficiency of the procedure. Design results for both unstiffened and stiffened plates are presented.
- An axisymmetric linear/high-order finite element for filament wound composite structuresRogers, Craig A. (Virginia Polytechnic Institute and State University, 1987)The development of an axisymmetric linear by high-order finite element to model filament-wound structures is presented. The primary objective of this work was to develop a ’design code' to analyze filament wound spherical pressure vessels. In order to develop a design-oriented analysis capability which can produce accurate results rather quickly with reduced input-data requirements, the total number of system equations must be reduced. To accomplish this task, a linear by high-order element was formulated which uses a single high-order displacement field finite element to model the total thickness of an axisymmetric composite structure. The displacement order for the in-plane direction remains linear, while the transverse order is user selectable. Numerical integration for stiffnesses is evaluated with respect to varying material properties and lamirna thicknesses in each individual element. Results from a computational economy study are presented showing potential time savings of 40 percent when compared to the conventional modeling scheme of using bi-linear elements. Actual test cases indicate that computation time savings may be as great as 55 percent when using linear by fourth-order elements and 45 percent when using linear by sixth-order elements. The accuracy of the element was evaluated by comparing the finite element results to elasticity solutions for isotropic, orthotropic, and filament-wound cylindrical pressure vessels. Most of the finite element results indicated a ±3 percent maximum error of the stresses compared to the elasticity results. The new linear by high order element stress results were nominally within ±2 percent of stresses calculated with conventional bilinear elements. Comparisons of finite element results for an actual filament-wound spherical pressure vessel slowed that linear by third- or fourth-order elements may be adequate for preliminary design purposes while the higher-order elements generally correlated better with the conventional bi-linear elements. Also presented is an outline of the design code and sample results for spherically wound pressure vessels.
- Determining parameters for stiff clays and residual soils using the self-boring pressuremeterMayu, Philippe (Virginia Polytechnic Institute and State University, 1987)As testing stiff soils in the laboratory often leads to information which is not consistent with field performance, research was undertaken to determine in situ the soil properties. Among the devices which generated interest is the self-boring pressuremeter (SBPM). In this research, two stiff soils of the Commonwealth of Virginia were tested: A residual soil found in Blacksburg and a very stiff, non-fissured, and sensitive clay, of marine origin, known as the Miocene clay of the downtown Richmond area. Testing the residual soil of Blacksburg with the SBPM led to the following new operational approaches: (1) a systematic use of a steel-sheath known as "Chinese lantern" to protect the membrane of the probe, (2) the development of a loading frame providing adequate reaction when self-boring in stiff soils, (3) the development of a new calibration unit for the SBPM which allows to calibrate the probe under conditions more like those encountered in stiff soils and, (4) the development of a high capacity computerized data acquisition system. Testing the residual soil also allowed to establish a sound database for this soil. In the Miocene clay, the laboratory test results indicate that conventional sampling technique which consists in pushing Shelby tubes disturbs significantly the soil and leads to scattered test results. In contrast, tests performed on samples taken from high-quality block samples indicate consistent behavior patterns. SBPM test results in the Miocene clay indicate that the clay exhibits high lateral stresses. They also indicate the existence of an anisotropic state of lateral stress which can be explained from the regional topography. The soil parameters interpreted from the SBPM test results in the Miocene clay compare well with the soil parameters determined in the laboratory on the block samples.
- Energy-absorption capability of composite tubes and beamsFarley, Gary L. (Virginia Polytechnic Institute and State University, 1989)In this study, the objective was to develop a method of predicting the energy-absorption capability of composite subfloor beam structures. Before it is possible to develop such an analysis capability, an in-depth understanding of the crushing process of composite materials must be achieved. Many variables affect the crushing process of composite structures, such as the constituent materials’ mechanical properties, specimen geometry, and crushing speed. A comprehensive experimental evaluation of tube specimens was conducted to develop insight into how composite structural elements crush and what are the controlling mechanisms In this study, the four characteristic crushing modes, transverse shearing, brittle fracturing, lamina bending, and local buckling were identified and the mechanisms that control the crushing process defined. An in-depth understanding was developed of how material properties, affect energy-absorption capability. For example, an increase in fiber and matrix stiffness and failure strain can, depending upon the configuration of the tube, increase energy-absorption capability. An analysis to predict the energy-absorption capability of composite tube specimens was developed and verified. Good agreement between experiment and prediction was obtained. Sine-wave and integrally stiffened composite beams were evaluated. Composite energy-absorbing beams crush in modes similar to tubular specimens that are made from the same material and have similar geometry. Energy-absorption trends of the composite beams are similar to energy-absorption trends from composite tube specimens. Composite beams are equal or superior energy absorbers to comparable geometry metallic beams. Finally, a simple and accurate method of predicting the energy-absorption capability of composite beams was developed. This analysis is based upon the energy-absorption capability of the beams’ constituent elements.
- Feasibility of helically stiffened construction for a formula racing car structural shellFont, Carlos Alejandro (Virginia Tech, 1991-02-05)The feasibility of replacing currently widely used sandwich construction with helically stiffened construction for a Formula racing car structural shell is studied. The torsional deformation behavior of circular and square cross-section shells is analyzed as an approximation to the real car structure. Shells with different sandwich and helically stiffened configurations are analyzed with finite elements. For closed square and circular cross-section shells, the highest torsional stiffness is obtained with helical stiffening. For circular cross-section shells with the cockpit cutout and reinforcements usually present in real racing car structural shells, ±4S' helically stiffened shells are 200% stiffer in torsion than sandwich shells. For square cross-section shells, the torsional stiffness improvement obtained with the helical stiffening is only 27%. The cross-sectional shape of the shell, cockpit opening, and different type of reinforcements (present in a real car structure) affects the selection of the best stiffening for torsional stiffness. The role of the terms of the stiffness matrix of the helically stiffened configuration in the torsional behavior of the shells is studied. The 0/90 waffle stiffening is more efficient than the helical stiffening for the square cross-section shells with the cutout and reinforcements. In the case of circular cross-section shells, the 0/90 waffle stiffening yields approximately the same results than the helical stiffening. The skin-stiffener configuration for maximum torsional stiffness depends on the crosssectional shape of the shell. The advantages of the ±45° helical stiffening over the sandwich construction depend on the cross-sectional shape of the shell and on the way the cutout region is reinforced.
- Finite element analyses on cohesive soil behavior due to advanced shield tunnelingShirasuna, Takeshi (Virginia Polytechnic Institute and State University, 1985)Soil tunnels are usually constructed using a shield with an open face. However, in the past decade, innovations in shield tunneling technology have brought closed-faced shields that provide continuous support to the face and permit tunneling through even the most difficult conditions of soft ground. These new machines are typically operated in such a way that during tunneling the soil at the face is actually heaved away from the shield. This operating procedure has been said to allow greater control of the ground movements around and above the shield, and to minimize detrimental settlements. However, there is little hard evidence to this effect and there is no rational basis to judge the actual influence of the soil heave. Building on former researchers’ efforts, this thesis is directed towards developing a suitable finite element method (FEM) approach to the advanced shield problem. The FEM program developed includes the Prevost elasto-plastic soil model, allows for analysis of development and dissipation of excess pore pressure, large deformation, and simulation of the construction procedure of advanced shield tunneling. This is the first time that the Prevost model was applied to a soft clay. Modifications were made, in particular for the parameter determination, to make the model applicable for the soft clay of San Francisco Bay Mud. Examination of two other soil models for the tunnel analysis, nonlinear pseudo-elastic and Cam Clay models, showed the Prevost model to be preferable. Loading procedures were also examined to accurately simulate the heaving and tail void closure effects. The finite element simulation of the N-2 sewer project, which is the first advanced shield project in the United States, demonstrated that the prediction agreed consistently well with the observations in the field. Further analyses indicated that heave at the face of the shield increases long·term consolidation settlements while it decreases immediate settlements and thus the final settlement may be reduced. The tail void simply increases settlements. The results suggest that strict control of heaving and elimination of tail void with proper and prompt grouting are crucial for mitigating ground movements with advanced shield tunneling.
- Finite element analysis of cellular steel sheet pile cofferdamsHardin, Kenneth O. (Virginia Tech, 1990-11-05)A cellular cofferdam represents a challenging soil-structure interaction problem. The cellular system consists of a combination of a flexible structure formed from interlocking sheet piles that is filled with soil. In the past, the cellular cofferdam has been viewed as a temporary structure, and the design procedures have been based on empirical concepts. Basic to these approaches are assumptions of soil and structural behavior that have, at best, only a rough accounting for soil-structure interaction. In the last decade, work on cofferdams has improved our understanding of the behavior of these systems. Documentation of performance has increased, and in a few cases major instrumentation efforts have been undertaken. Concurrently, finite element methods have been introduced for the analysis of cofferdams. Where the finite element models have been properly calibrated by field performance, they have reasonably predicted the principal aspects of cofferdam behavior. Results of the finite element models have also served to help explain some aspects of the soil-structure interaction process in the cofferdam system. Two finite element programs are used in this research, AXISHL and GPS. The first of these is an axisymmetric analysis tool which is applicable to the case of filling of a main cell. The second program provides a simplified means of analyzing the main/arc cell and common wall system. Both programs are used in a series of parameter studies with the objective to provide information that will allow improvement of the state-of-the-art of design for cofferdams. An analytical solution is proposed which allows an insight to be developed as to how the clamping effect at the dredge line affects the behavior of the system. A simplified calculation procedure which has some of the characteristics of the finite element analysis is developed to supplement the need for a finite element analysis.
- The influence of cementation on liquefaction resistance of sandsIwabuchi, Jotaro (Virginia Polytechnic Institute and State University, 1986)Cohesionless sands are known to be susceptible to failure by liquefaction when they are saturated and subjected to earthquake shaking. Considerable study has been directed towards this subject over the past 20 years in recognition of the possibility of large-scale property damage or loss of life due to this type of failure. Recent evidence has shown that small degrees of cementation in a sand significantly reduce the likelihood of liquefication. However, the work to date has been limited to studies with conventional testing devices and simple loading paths. These devices are suspected of inducing premature failure in cemented soils, and are not capable of modeling the effects of multiaxial loading. In this investigation, there were two major objectives. The first involved the development and fabrication of a new three~dimensional shear device with the capability of applying load to cemented sands with a minimum of stress concentration effects, and of using load paths which are more representative of the true effects of an earthquake than is possible in conventional equipment. The second concerned performance of a series of production tests to investigate the behavior of cemented sands under a range of earthquake loading paths. The production tests were largely performed using the new three—dimensional shear device. The test results showed that cemented soils have more resistance to earthquake loading than previously thought since stress concentration effects in conventional testing do induce premature failure through the effects of stress concentrations. On the other hand, it was found that either cemented or uncemented sands show less resistance to earthquake loadings if multiaxial stress conditions are applied to the sample as opposed to uniaxial loadings. This is important in explaining the fact that sites with seemingly similar conditions often show different behavior, since slightly different earthquake loading pattems can cause different responses. One factor explaining differences in response is found to be the mean normal stress, which is not the same for all loadings, and plays an important role in the pore pressures developed in the soil.
- Movements of footings and retaining wallsTan, Chia K. (Virginia Tech, 1991)The objectives of this dissertation are: (1) to examine the relationship between the accuracy and reliability of methods of estimating settlements of footings on sand and gravel, (2) to develop a procedure for estimating horizontal movements and rotations of footings without the need of determining soil modulus values, and (3) to develop a simple procedure for calculating movements of retaining walls due to the weight of backfill. The accuracy and reliability of twelve methods of estimating settlements of footings on sand and gravels were examined by comparing calculated settlements with the measured values. Eleven of the methods are based on Standard Penetration Test Results, while Schmertmann’s method is based on Cone Penetration Test Results. The study showed that methods which are more accurate tend to underestimate settlements about half of the time; while those which are more reliable (in the sense that they infrequently underestimate settlements) tend to be less accurate. The study also indicated that these methods of estimating settlements of footings on sands and gravels involve approximately the same relationship between accuracy and reliability, regardless of the approach that they use to calculate settlement. The results demonstrate that there is a tradeoff between accuracy and reliability. Any of the methods can be adjusted to achieve approximately the same combination of accuracy and reliability as other method. A simple procedure is presented to relate horizontal movements and rotations of footings to settlements. The procedure does not require the determination of soil modulus, and its accuracy and reliability can be assessed qualitatively by association with the method used to calculate the settlement. A simple procedure based on elastic theory was also developed to estimate movements of abutments and retaining walls due to the weight of backfill placed behind them. To avoid the inherent difficulty in determining the soil modulus, a procedure for relating these movements to the settlement of the wall was also developed. The new procedure was applied to a case history, and the calculated movements agree quite well with those calculated using the finite element method, and with field observations.
- Optimal Design of Variable-Stiffness Fiber-Reinforced Composites Using Cellular AutomataSetoodeh, Shahriar (Virginia Tech, 2005-09-21)The growing number of applications of composite materials in aerospace and naval structures along with advancements in manufacturing technologies demand continuous innovations in the design of composite structures. In the traditional design of composite laminates, fiber orientation angles are constant for each layer and are usually limited to 0, 90, and ±45 degrees. To fully benefit from the directional properties of composite laminates, such limitations have to be removed. The concept of variable-stiffness laminates allows the stiffness properties to vary spatially over the laminate. Through tailoring of fiber orientations and laminate thickness spatially in an optimal fashion, mechanical properties of a part can be improved. In this thesis, the optimal design of variable-stiffness fiber-reinforced composite laminates is studied using an emerging numerical engineering optimization scheme based on the cellular automata paradigm. A cellular automaton (CA) based design scheme uses local update rules for both field variables (displacements) and design variables (lay-up configuration and laminate density measure) in an iterative fashion to convergence to an optimal design. In the present work, the displacements are updated based on the principle of local equilibrium and the design variables are updated according to the optimality criteria for minimum compliance design. A closed form displacement update rule for constant thickness isotropic continua is derived, while for the general anisotropic continua with variable thickness a numeric update rule is used. Combined lay-up and topology design of variable-stiffness flat laminates is performed under the action of in-plane loads and bending loads. An optimality criteria based formulation is used to obtain local design rules for minimum compliance design subject to a volume constraint. It is shown that the design rule splits into a two step application. In the first step an optimal lay-up configuration is computed and in the second step the density measure is obtained. The spatial lay-up design problem is formulated using both fiber angles and lamination parameters as design variables. A weighted average formulation is used to handle multiple load case designs. Numerical studies investigate the performance of the proposed design methodology. The optimal lay-up configuration is independent of the lattice density with more details emerging as the density is increased. Moreover, combined topology and lay-up designs are free of checkerboard patterns. The lay-up design problem is also solved using lamination parameters instead of the fiber orientation angles. The use of lamination parameters has two key features: first, the convexity of the minimization problem guarantees a global minimum; second, for both in-plane and bending problems it limits the number of design variables to four regardless of the actual number of layers, thereby simplifying the optimization task. Moreover, it improves the convergence rate of the iterative design scheme as compared to using fiber angles as design variables. Design parametrization using lamination parameters provides a theoretically better design, however, manufacturability of the designs is not certain. The cases of general, balanced symmetric, and balanced symmetric with equal thickness layers are studied separately. The feasible domain for laminates with equal thickness layers is presented for an increasing number of layers. A restricted problem is proposed that maintains the convexity of the design space for laminates with equal thickness layers. A recursive formulation for computing fiber angles for this case is also presented. On the computational side of the effort, a parallel version of the present CA formulation is implemented on message passing multiprocessor clusters. A standard parallel implementation does not converge for an increased number of processors. Detailed analysis revealed that the convergence problem is due to a Jacobi type iteration scheme, and a pure Gauss-Seidel type iteration through a pipeline implementation completely resolved the convergence problem. Timing results giving the speedup for the pipeline implementation were obtained for up to 260 processors. This work was supported by Grant NAG-1-01105 from NASA Langley Research Center. Special thanks to our project monitor Dr. Damodar R. Ambur for his technical guidance.
- Prediction model for the onset of edge-effect delamination at holes in composite laminatesShalev, Doron (Virginia Polytechnic Institute and State University, 1988)Composite laminates are prone to delamination at free edges, straight edges or at holes, due to the mismatch at interfaces where two adjacent plies have different fiber orientations and/or different material properties. The linear analysis of the mismatch at the edge results in a mathematical singularity. That phenomenon occurs in a boundary layer and has to be treated mathematically and physically as such. In the literature it is called the "Boundary Layer Effect" or simply the "Edge Effect". It is of great importance to recognize and be able to predict delamination locations at edges prone to such events. The goal of this research was to create a model capable of providing such a prediction. In an effort to generalize the model, the more complicated case of a free edge at holes in the composite laminate was chosen rather than the case of a straight free edge. A sequel of three major efforts was completed: 1) Development of the analysis of the free-edge effect at a hole in a composite laminate, 2) Performance of an extensive experimental program to provide data for the creation of the prediction model, and 3) On the basis of the analysis, establishment of the model, and comparison with the experimental results. The prediction model consists of two major products of the analysis, the order of the singularity and the strain energy release rate. Both are useful in locating the interface most prone to delaminate and the point along the hole circumference where it initiates. Two material systems (AS4/3501-6 and AS4/1808) and two stacking sequences [(0/45/0/-45)s)₄] and [ (0/45/90/-45)s)₄]s , quasi-orthotropic and quasi-isotropic respectively, were quasi-statically tested under tension and compression. The specimens were X-rayed after each loading stage in order to locate the initiation of delaminations. The fact that both materials consisted of the same type of fibers, was an excellent opportunity to examine the performance of the matrix and its influence on the process of delamination. Matrix dependent behavior was successfully examined and studied through the experiments and the prediction model. Results showed good correlation and high sensitivity to the type of matrix material involved.
- Scaling effects in the static and dynamic response of graphite- epoxy beam-columnsJackson, Karen E. (Virginia Tech, 1990-05-05)Scale model technology represents one method of investigating the behavior of advanced, weight-efficient composite structures under a variety of loading conditions. Testing of scale models can provide a cost effective alternative to destructive testing of expensive composite prototypes and can be used to verify predictions obtained from finite element analyses. It is necessary, however, to understand the limitations involved in testing scale model structures before the technique can be fully utilized. The objective of this research is to characterize these limitations, or scaling effects, in the large deflection response and failure of composite beams. Scale model beams were loaded with an eccentric axial compressive load designed to produce large bending deflections and global failure.
- Thermomechanical Response of Shape Memory Alloy Hybrid CompositesTurner, Travis Lee (Virginia Tech, 2000-11-17)This study examines the use of embedded shape memory alloy (SMA)actuators for adaptive control of the themomechanical response of composite structures. Control of static and dynamic responses are demonstrated including thermal buckling, thermal post-buckling, vibration, sonic fatigue, and acoustic transmission. A thermomechanical model is presented for analyzing such shape memory alloy hybrid composite (SMAHC) structures exposed to thermal and mechanical loads. Also presented are (1) fabrication procedures for SMAHC specimens, (2) characterization of the constituent materials for model quantification, (3) development of the test apparatus for conducting static and dynamic experiments on specimens with and without SMA, (4) discussion of the experimental results, and (5) validation of the analytical and numerical tools developed in the study. The constitutive model developed to describe the mechanics of a SMAHC lamina captures the material nonlinearity with temperature of the SMA and matrix material if necessary. It is in a form that is amenable to commercial finite element (FE) code implementation. The model is valid for constrained, restrained, or free recovery configurations with appropriate measurements of fundamental engineering properties. This constitutive model is used along with classical lamination theory and the FE method to formulate the equations of motion for panel-type structures subjected to steady-state thermal and dynamic mechanical loads. Mechanical loads that are considered include acoustic pressure, inertial (base acceleration), and concentrated forces. Four solution types are developed from the governing equations including thermal buckling, thermal post-buckling, dynamic response, and acoustic transmission/radiation. These solution procedures are compared with closed-form and/or other known solutions to benchmark the numerical tools developed in this study. Practical solutions for overcoming fabrication issues and obtaining repeatable specimens are demonstrated. Results from characterization of the SMA constituent are highlighted with regard to their impact on thermomechanical modeling. Results from static and dynamic tests on a SMAHC beam specimen are presented, which demonstrate the enormous control authority of the SMA actuators. Excellent agreement is achieved between the predicted and measured responses including thermal buckling, thermal post-buckling, and dynamic response due to inertial loading. The validated model and thermomechanical analysis tools are used to demonstrate a variety of static and dynamic response behaviors associated with SMAHC structures. Topics of discussion include the fundamental mechanics of SMAHC structures, control of static (thermal buckling and post-buckling) and dynamic responses (vibration, sonic fatigue, and acoustic transmission), and SMAHC design considerations for these applications. The dynamic response performance of a SMAHC panel specimen is compared to conventional response abatement approaches. SMAHCs are shown to have significant advantages for vibration, sonic fatigue, and noise control.