Design code\standard for composite structure 1

[Jason8zhu]

With some knowledge om composite mechanics, i am going to design some composite structure for civil envineering with plate and pipes.


u know for steel structures, we have plenty of code to follow.
would you please advise if any composite design code or standard to follow?

tks.

 

[EdClymer]

Jason


Assuming you mean composite, in the form of glass/carbon of similar fabrics, and resins ie Polyester, or epoxide...rather than steel and concrete.

If the structure you were planning to design was a fluid containing tank or vessel ; then BS 4994:87 (glass reinforced plastics) is one place to start.

A tried and tested standard (in that we know where the errors, mistooks and typos are). This standard also includes plates and panels. In the USA they have ASME RTP-1 for same applications.

In mid 90s, someone thought we needed a new standard...prEN13121-part 3, first edition 2000, and then 2008 and 2014...perhaps one day a workable standard (in which we have confidence) will be published. This has references to Eurocode for wind, snow etc.

Trust this is of help

Regards

Ed

E G Clymer
Birmingham
England


Ed Clymer
Resinfab & Associates
England

 

[RPstress]

Thanks Ed Clymer. Some useful stuff in there.

A lot of the methods have been developed by and for aerospace which doesn't have the same level of prescriptive design methods as the sort of structure that Jason8zhu seems interested in. Methods and allowables are usually covered in companies' copyrighted specs, although some are commercially available (e.g., M.C.Y. Niu, Airframe Stress Analysis and Sizing and Composite Airframe Structures). There are a lot more references tucked away in posts here in Eng-Tips. Works on marine composites can be helpful being sort of half way between airframe and static civil structures (look for authors Eric Greene and Marcio Vasconcellos; they've both put textbooks on the net, both called Marine Composites). There are similar aspects to wind turbine design and searching the net can yield useful references (try looking for "optimat composite").

There's a lot of useful stuff in CMH-17 (descendent of MIL-HDBK-17, sort-of-a-bit-like-but-not-really MIL-HDBK-5 for composites). Googling CMH-17 gives a lot of options for downloading CMH-17 and MIL-HDBK-17 (one of the first hits is

https://www.wbdg.org/ccb/FEDMIL/hdbk17_3f.pdf).

For basic materials information search for NIAR NCAMP and see the data held by the organization based in Wichita, where there is a valiant attempt to make composites data public and reduce costs of accessing material data.

Note that Roark's Formulas for Stress and Strain, eighth ed has a section on composite materials (not sure how useful it is but it's at least a beginning of material (probably) relevant to civil engineering).

Those of us involved in designing the types of civil structures sometimes needed in aerospace companies (ground support equipment, test rigs and tooling are the main items in this category) use a simplified version of the usual aerospace methods, but these are almost always based on simple allowable stress design (ASD) and may fall short of requirements which need to include some aspects of load and resistance factor design (LRFD).

 

[Jason8zhu]

Thanks Clymer & RPstress for your valuable informations.

Yeah, my major interest is the desgin of CFRP/GFRP/Sandwiches for Civil structures such as Bridges, part of buildings and temporary frames.
ASME RTP-1 is useful for me on material test and I also refer to EN13706 & AMTS-SWP-0048.
I am formerly a Steel Structure guy using AISC & Roark's Formulas 7th edition. With RPstress’s guidance, I searched Roark's Formulas 8th and found its content. In 8th edition, we are glad to see that Roark's Formulas includes composites in Chapter 20. Currently, design practice in Aerospace structure pioneered my knowledge. Later on, marine composites should be the next.

Yesterday, I happened to find a European design guide: Structure Design of Polymer Composites by John Clarks on 1996. Did anybody refer to this book during design?

 

[RPstress]

Also try ETL 1110-2-548, “Composite Materials for Civil Engineering Structures” from the U.S. Army Corps of Engineers.

http://www.dtic.mil/dtic/tr/fulltext/u2/a403282.pdf

 

[Jason8zhu]

Thanks, RPstress. The ETL is verybuseful for composite design on civil for me.