Application of composite materials are now wide spread and all around us - Planes, Trains and Automobiles, Tennis rackets, Golf clubs, Hockey sticks, Medical supplies, Prosthetics, Oil and Natural gas pipelines, Oil Rigs, pedestrian and vehicle bridges, Building materials, Architectural Marvels,  Helmets, Bullet-proof armors and personal equipment, PCBs, Smartphones and Laptops cases and covers, Electrical enclosures, Pothole covers, Water tanks, and the list goes on. 

Almost all kinds of metallic and non-metallic materials available to mankind can be used to create composite material parts. Since, by definition, combination of any two materials creates a composite part, possibilities for application of composites in real-life are unlimited, The growth in application of composite materials in past half-a-century is a proof of it.

The discussion on composite materials, processes and their applications is now as deep as an ocean. Numerous books, reports and research papers are available to take a deep dive into these and many other topics of interest related to composites. Here, I am going to focus on the specific topic of structural applications of composites. 

In simple terms, a structure is a part or an assembly of parts that resist deformation under an applied load. In other words, a structural part is expected to carry the load; a non-structural part is not and is simply cosmetic.  The loads can be mechanical, environmental such as temperature and humidity or  hygro-thermal, electrical, magnetic, etc. We all know that the resistance to deformation under applied loads creates strains and stresses in the structure. In order to assess the load carrying capability of structures, we start with the study of fundamental subjects such as physics, chemistry, math, statics, dynamics, strength of materials, material science,  etc, Then, we move on to advanced subjects such as theory of elasticity, rods, shafts, trusses, beams, plates, shells, vibrations, stability, damage and failure, crack growth, fracture mechanics, fatigue, large deformations, plasticity, nonlinear, etc.  Almost all these topics are of interest and equally applicable to  understanding the stresses and strain in structural parts made from any material be it metallic, non-metallic, or composite materials. 

Composite materials introduce complexities in the study of these subjects and application of the theories contained therein due to one or more of the following reasons:

(i) presence and interaction of two or more constituents that make up the composite materials

(ii) presence of more than one layer to build the final part 

(iii) directional behavior of physical, mechanical, thermal, electrical, or other properties of the resultant composite material or final part, a.k.a. anisotropic material behavior of composite materials  

Hence, to perform correct and accurate analysis of structures fabricated from composite materials, numerous advancements have been made to the subjects of theory of elasticity, rods, shafts, trusses, beams, plates, shells, vibrations, stability, damage and failure, crack growth, fracture mechanics, fatigue, large deformations, plasticity, nonlinear, etc. over more than a century. To name a few, theory of anisotropic elasticity and plasticity, advanced theories of composite beams, plates and shells, textile composites, modeling of fiber and matrix failure mechanisms in composites, cohesive zone models, continuum and discrete damage modeling, hierarchical failure models, composite material specific failure criteria such as Tsai, Hashin, Yamada, LaRC0x are some such areas of studies that have evolved to support advancement in computational mechanics of composite material structures. 

The advent of computers and computational power in the past half-a century has resulted in a glut of finite element-based tools to perform structural analyses. Many of such tools have been commercialized and have very powerful static, implicit and explicit solvers, and pre- and post-processing capabilities. No doubt the commercial finite element packages have their unique value in supporting the analyses of composite materials and structures during a product design cycle. However, these FE packages are 

(i) very expensive to buy and/or lease, 

(ii) have a steep learning curve and 

(iii) are time consuming to perform trade studies for simple changes in materials(s), ply-lay-ups and geometric features, especially for the application of composite structures. 

Analytical tools based on classical methods (hand calculations, for example) fill in this gap and have their own place in the analyses and overall product design process of composite structures.In spite of availability of powerful commercial FE software, most big OEMs and Tier I/II suppliers across many industries who are involved in the design, analysis and manufacturing of structures made out of composite materials have spent good amount of manpower and revenue $$$ to develop their own in-house classical hand analyses tools for composite structures. Same is also true across academia where tremendous number of efforts are put together to re-invent the same classical hand analyses tools for analyses of composite structures year after year. And then, there are many sub-Tier suppliers and small business engaged in the design, analyses and manufacturing of composite parts and structures who would prefer not to spend their money to either buy expensive commercial FE software packages or develop the classical hand analyses tools, unless necessary.

3P Composites, LLC has embarked on a mission to develop advanced classical methods and tools for practical analyses of composite structures. 3P Composites, LLC is committed to the development of highly affordable advanced web-based tools to aid in the quick and accurate practical analysis of laminated composite and sandwich structures. These web-based tools, also called the 3pcsolvers  can help perform bending, buckling, free vibration and stress analysis of laminated composite and sandwich structures such as plates, shells and beams subjected to mechanical force and moment loads, and environmental effects of temperature and moisture.  Stress concentration effects due to circular and elliptical cutouts can also be analyzed using these web-based solvers. Furthermore, strength prediction analysis of composite laminates can be performed using well-known failure theories of composite materials such as Max Stress/Strain and Tsai-Wu.  A list of released and a few upcoming web-based composite analysis tools is given below:

1. Analysis of Composite Laminates subjected to Hygro-thermo-mechanical loads   
2. Bending Analysis of Simply Supported Anisotropic Laminated Composite Plates   
3. Buckling Analysis of Simply Supported Anisotropic Laminated Composite Plates   
4. Free Vibration Analysis of Simply Supported Anisotropic Laminated Composite Plates   
5. Analysis of Sandwich Panels subjected to Hygro-thermo-mechanical loads   
6. Bending Analysis of Simply Supported Sandwich Panels   
7. Buckling Analysis of Simply Supported Sandwich Panels   
8. Free Vibration Analysis of Simply Supported Sandwich Panels   
9. Strength Prediction of Laminated Composite Plates with Circular and Elliptical Cutouts   
10. Strength Prediction of Sandwich Composite Plates with Circular and Elliptical Cutouts   
11. Analysis of laminated   composite cylindrical panels subjected to Hygro-thermo-mechanical loads  
12.  Bending Analysis of Simply   Supported Anisotropic Laminated Composite Cylindrical Panels and Shells    
13. Buckling Analysis of Simply   Supported Anisotropic Laminated Composite Cylindrical Panels and Shells    
14. Free Vibration Analysis of   Simply Supported Anisotropic Laminated Composite Cylindrical Panels and   Shells    
15. Analysis of Cylindrical   Sandwich Panels subjected to Hygro-thermo-mechanical loads   
16. Bending Analysis of Simply   Supported Anisotropic Cylindrical Sandwich Panels and Shells    
17. Buckling Analysis of Simply   Supported Anisotropic Laminated Composite Cylindrical Sandwich Panels and   Shells    
18. Free Vibration Analysis of   Simply Supported Anisotropic Laminated Composite Cylindrical Sandwich Panels   and Shells    
19. Bearing-Bypass Analysis of   Mechanically Fastened Laminated Composite Panels   
20. Bearing-Bypass Analysis of   Mechanically Fastened Laminated Composite and Sandwich Panels    

These web-based analyses tools can help composites industries and researchers focus on innovating the new applications of composite materials, and use their manpower & revenues efficiently.  There is no need to invest in expensive commercial finite element software packages for designing composite parts and structures for simpler applications or to perform quick trade-off studies or even invest time and money in developing composite analysis tools that are now easily accessible online 24/7.   

 Future blogs will discuss the applications of these solvers through practical  examples and case studies relevant to composite materials and structures. Stay tuned for blogs on 3pcsolvers ! and case studies on practical analyses of composite structures!