COMBINED DEFORMATIONS §9-1 SUMMARY 1 Composite deformation: Structural members will produce several types of simple deformations when subjected to complex external loads. The stress corresponding to each simple deformation can not be neglected when the magnitude of each stress has the same order. This kind of deformation is called the composite deformation P O R M§9–1 SUMMARY M P R z x y P P 1、Composite deformation：Structural members will produce several types of simple deformations when subjected to complex external loads .The stress corresponding to each simple deformation can not be neglected when the magnitude of each stress has the same order .This kind of deformation is called the composite deformation . 5