1. Inordertosimplifythemathematicsthedesignparametrizationischosenasillustratedinfig.3.1.An alternative parametrization with expansion in terms of shape design functions is formulated in Demsand Mroz (1978), apaperclosely relatedto this paper. We assume a homogeneous state for theenergydensity u, withinthevolume V, related totheshapeparameter h,Letusnowsubjectthe shape to variation from only two parameters h| and hj .Furthermore,letthetotalvolume V ofthe structure (continuum) befixed,then
2. A few aspects related to the stress distribution should be mentioned. In relation to fatigue, not onlythe maximumstress isimportant but alsothe size of the domains where these stresses are found is important. The paper by Lund (1998) shows this aspect of optimal designformulation.