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A load combination sums or envelopes the analysis results of certain load cases. Summation is often suitable for a linear analysis in which results are superimposed, such as with 1.2*DL+1.6*LL. For nonlinear analysis, it is often best to combine load patterns within load cases, then use load combinations to compute response envelopes. Load - combination results include displacements and forces at joint locations, and internal member forces and stresses.
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