Global shared-layer blending method for stacking sequence optimization design and blending of composite structures

A framework for design and optimization of tapered composite structures. Part I: From individual panel to global blending structure

“…A new framework for design of tapered composite structures is proposed based on two techniques in [24,25]; the design concept is extending from an individual panel to the overall structure by improving its blending property. All complex constraints are considered, they are divided into different sets and implemented at various steps.…”

“…A stacking sequence of individual panel is obtained by using sequential permutation table (SPT) [25] without considering a blending requirement. However, to maintain the maximal blending property, the GSLB method [24] is adopted. Additionally, several new techniques are developed and combined with the previous two techniques.…”

“…The sequential permutation table (SPT) method was developed in [24]. It was observed that the k cb can be expressed as a linear combination of the ply orientation based stacking sequences as shown in Eqs.…”

“…Ply tailoring, numbers of plies and a stacking sequence are designed separately in three phases with manufacturing constraints divided and imposed in each phase. Most recently, Jing [23][24][25] developed algorithms based on a classical lamination theory (CLT) to solve stacking-sequence optimization problem. A permutation search (PS) algorithm [23] was developed for sequence optimization as well as a sequential permutation table (SPT) method [25], with the buckling load factor expressed as a linear function of a sum of buckling load factors at every stacking position corresponding to ply orientation.…”

“…A permutation search (PS) algorithm [23] was developed for sequence optimization as well as a sequential permutation table (SPT) method [25], with the buckling load factor expressed as a linear function of a sum of buckling load factors at every stacking position corresponding to ply orientation. Besides, a global shared-layer blending (GSLB) method [24] was proposed based on the SLB method [14] to identify layer shape/ maintain blending property according to the structural thickness distribution. From the above analysis, blending is the main concern of design problem, because a higher blending property/fewer plydrops can decrease stress concentration as well as improve structural integrity.…”