limit load in structutal integrity

[mmjan72]

1.what is 'limit load' in the structural integrity procedures like R6; BS codes etc. Is this the load where the plasticity starts or it is the max. plastic load or collapse load?
2 for SENB specimen will it be FY=(SIGMA_Yield)*(1-a/W) ??

 

[rb1957]

without knowing the codes, "limit" load in the airplane business is the typical service load and must not cause "significant" yielding ... it's less than the load that initates plasticity.

hope that helps

 

[swearingen]

In structural engineering in the U.S., limit state design is simply a set of limits you put on the design. These limits may be in terms of force, stress, deflection or vibration. They may not correspond to a particular material property, but they always correspond to the safety and/or serviceability of the structure. The codes set limits such that the structure is not only safe, but is comfortable as well.

 

[mmjan72]

to elaborate the problem, i meant about the plastic limit load which is being used in the codes of 'flawed' or cracked structure, (i mean codes like ASME section XI ; R6 ;BS7910 etc.) to avoid the plastic collapse .
so is it the start of plasticity or the max plasticity.
my question is with reference to FAD (failure assesment diagram).
2. so if i assume a flawed speciment (like SENB) with width W and flaw length 'a' the will the limit load be (1-a/W)*Sy?

thanks