十字叠层板横向剪切刚度的计算方法
CALCULATION METHOD FOR DETERMINING TRANSVERSE SHEAR STIFFNESS COEFFICIENT OF CROSS-PLY LAMINATE
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摘要: 本文研究了十字叠层板横向剪切刚度系数的计算方法.指出前人采用的横向剪应力为抛物线分布的假设不够准确,使Cii的计算值产生误差.本文首先推导了横向剪应力沿厚度分布的计算公式,然后用幂级数拟合了近似权函数,用权函数法和能量法对两种铺层结构的碳/环氧十字叠层板的Cii进行了计算.对比了两种方法的结果,并与文献1的方法作了对比.结果表明,对于对称层板本文权函数法与文献1的结果基本一致;而对于非对称叠层板,二者差别明显.能量法结果与权函数法对比,前者更精确.Abstract: This paper presents two calculation methods for determining transverse shear stiffness coefficients,weight function method and strain energy method.The first method is similar to that proposed in Ref.〔1〕,with the exception of abandoning the assumption of parabolic distribution of transverse shear stress through thickness of the lamicate.Becaus the real distribution of shear stress is not exactly parabelie,especially for unsymmetrical laminates,the formula in Ref.〔1〕often yields inaccuracy. First of all,the formulas of transverse shear stress were derived.The least square method wa,s used to obtain the approximate weight functions for both symmetrical and unsytrimetrical laminates.Then.the shear stiffness coefficients were calculated by using the two methods. The results show that for the unsyrrirrtetrical laminat:the weight functiara method is better than the formula of Ref.〔1〕.As foe the comperison between the two methods of this paper,strain energy rnethod might be supcrior to the other one.