Analysis assumptions in docs

[robbievanleeuwen]

@Agent6-6-6:

I kind of think to go along with this conversation maybe the docs also need a section/page on the analysis assumptions so user is fully informed on any assumptions and possible pitfalls. Most of this is assumed in any analysis, but no harm in explicitly stating it for clarity. You know the usual stuff like for example:-

• Plane sections remain plane (Bernoulli), i.e. sections perpendicular to the axis of bending that are plane before bending remain plane after bending

• The strains in both the concrete and the reinforcement varies linearly through the depth of the member, i.e. cross section strains are proportional to the distance from the neutral axis

• The strain in the reinforcement is equal to the strain in the concrete at the same level/position, i.e. a perfect bond exists between the reinforcement and the concrete

• Any reinforcement is considered as being characterised by a single strain value at the centre of the reinforcement, i.e. for the analysis the strain gradient across the bar diameter is not considered

• The maximum strain at the extreme concrete compression fibre is assumed to reach a maximum limiting compressive strain

• The stresses in the concrete and reinforcement can be determined from the strains using stress-strain curves for both concrete and steel

• The tensile strength of concrete is neglected in strength calculations

• The member does not buckle before the ultimate strength of the cross section is attained

• The compressive stress-strain relationship for concrete may be assumed to be rectangular, trapezoidal, bilinear, parabolic, or any other arbitrary shape that results in prediction of strength in substantial agreement with the results of comprehensive tests

• Other???

Originally posted by @Agent6-6-6 in #9 (reply in thread)