Utilization Of The Building-Block Approach In Structural Mechanics Research

In the last 20 years NASA has worked in collaboration with industry to develop enabling technologies needed to make aircraft safer and more affordable, extend their lifetime, improve their reliability, better understand their behavior, and reduce their weight. To support these efforts, research programs starting with ideas and culminating in full-scale structural testing were conducted at the NASA Langley Research Center. Each program contained development efforts that (a) started with selecting the material system and manufacturing approach; (b) moved on to experimentation and analysis of small samples to characterize the system and quantify behavior in the presence of defects like damage and imperfections; (c) progressed on to examining larger structures to examine buckling behavior, combined loadings, and built-up structures; and (d) finally moved to complicated subcomponents and full-scale components. Each step along the way was supported by detailed analysis, including tool development, to prove that the behavior of these structures was well-understood and predictable. This approach for developing technology became known as the "building-block" approach. In the Advanced Composites Technology Program and the High Speed Research Program the building-block approach was used to develop a true understanding of the response of the structures involved through experimentation and analysis. The philosophy that if the structural response couldn't be accurately predicted, it wasn't really understood, was critical to the progression of these programs. To this end, analytical techniques including closed-form and finite elements were employed and experimentation used to verify assumptions at each step along the way. This paper presents a discussion of the utilization of the building-block approach described previously in structural mechanics research and development programs at NASA Langley Research Center. Specific examples that illustrate the use of this approach are included from recent research and development programs for both subsonic and supersonic transports.

[1]  Patrick Thrash,et al.  Progress in manufacturing large primary aircraft structures using the stitching/RTM process , 1993 .

[2]  John G. Davis.  Advanced composites technology program , 1993 .

[3]  Dawn C. Jegley,et al.  Behavior of Compression-Loaded Composite Panels with Stringer Terminations and Impact Damage , 1998 .

[4]  H. Benson Dexter,et al.  Development of Stitched, Braided and Woven Composite Structures in the ACT Program and at Langley Re , 1997 .

[5]  D R Ambur,et al.  Damage-Tolerance Characteristics of Composite Fuselage Sandwich Structures With Thick Facesheets , 1997 .

[6]  Damodar R. Ambur,et al.  Structural Response of Composite Sandwich Panels Impacted With and Without Compression Loading , 1999 .

[7]  J. H. Starnes,et al.  Parametric Study on the Response of Compression-Loaded Composite Shells With Geometric and Material Imperfections , 2004 .

[8]  D R Ambur,et al.  Compression Response of a Sandwich Fuselage Keel Panel With and Without Damage , 1997 .

[9]  Peter J. Smith,et al.  Advanced composite fuselage technology , 1993 .

[10]  D. Jegley.  Compression Behavior of Graphite-Thermoplastic and Graphite-Epoxy Panels with Circular Holes or Impact Damage. , 1991 .

[11]  C Jegley Dawn,et al.  Structural Testing of a Stitched/Resin Film Infused Graphite-Epoxy Wing Box , 2001 .

[12]  Damodar R. Ambur,et al.  Damage Progression in Buckle-Resistant Notched Composite Plates Loaded in Uniaxial Compression , 2001 .

[13]  R Ambur Damodar,et al.  Analytical Prediction of Damage Growth in Notched Composite Panels Loaded in Axial Compression , 1999 .

[14]  C Jegley Dawn,et al.  Structural Test Documentation and Results for the McDonnell Douglas All-Composite Wing Stub Box , 1997 .

[15]  W. Waters,et al.  Test and analysis of a stitched RFI graphite-epoxy panel with a fuel access door , 1994 .

[16]  Arthur V. Hawley.  Development of stitched/RTM primary structures for transport aircraft , 1993 .

[17]  Marshall Rouse,et al.  Fuselage response simulation of stiffened panels using a pressure-box test machine , 1995 .

[18]  J. G. Williams,et al.  Effect of resin on impact damage tolerance of graphite/epoxy laminates , 1981 .

[19]  Harold G. Bush,et al.  Correlation of Structural Analysis and Test Results for the McDonnell Douglas Stitched/RFI All-Composite Wing Stub Box , 1996 .

[20]  Jeffrey A. Cerro,et al.  Analysis of a D-box fixture for testing curved stiffened aircraft fuselage panels in axial compression and internal pressure , 1994 .

[21]  Alan Markus,et al.  Composites technology for transport primary structure , 1991 .

[22]  Dawn C. Jegley.  Analysis of selected compression splice joint locations in a graphite-epoxy transport wing stub box , 1995 .

[23]  Karal Michael,et al.  AST Composite Wing Program---Executive Summary , 2001 .

[24]  Andrew E. Lovejoy,et al.  Structural Response and Failure of a Full-Scale Stitched Graphite-Epoxy Wing , 2003 .

[25]  B. W. Flynn,et al.  Advanced Technology Composite Fuselage-Structural Performance , 1997 .

[26]  R. M. Stephen,et al.  Evaluation of the Compressive Response of Notched Composite Panels Using a Full-Field Displacement Measurement System , 1999 .

[27]  John G. Davis.  Overview of the ACT program , 1992 .