材料期刊网

为探究穿透裂缝对复合材料缠绕圆柱壳承载能力及失效模式的影响,首先开展不同壁厚含预裂缝复合材料缠绕圆柱壳轴向压缩试验.对于A系列厚壁圆柱壳,裂缝导致承载能力下降53.96%,失效模式由局部屈曲转化为裂缝扩展、脆性断裂;而B系列薄壁圆柱壳均发生局部屈曲,裂缝使承载能力下降12.59%.其次,采用有限元软件ABAQUS 6.14,基于非线性RIKS算法,建立轴压作用下含预裂缝复合材料圆柱壳极限承载能力计算模型,通过引入Hashin失效准则及损伤演化判据,预测结构渐进破坏模式及极限荷载.数值结果与试验数据吻合良好,最大误差为7.01%,验证了数值算法的可靠性.在此基础上,探讨裂缝方向、缠绕角度对含预裂缝复合材料圆柱壳极限承载的影响,可知:对于±55°螺旋铺层复合材料圆柱壳,随裂缝角度α增加,极限承载能力先升高再降低,当α=45°时,具备最大承载能力;对于含开缝角α=15°、45°、55°缠绕圆柱壳,随缠绕角θ增加,其承载能力呈先上升后下降趋势.且开缝角越小,缠绕角度对极限荷载的影响越大,当缠绕角θ=30°时,达到最大承载能力.

In this study, the ultimate load capability and failure modes of filament-wounded composite cylindrical shells with through crack has been investigated.First, axial compression test was carried out for two series filament-wounded cracked cylindrical shells.For A series thick wall cylindrical shell, crack led a 53.96% drop in load capability, and the failure mode transferred from local buckling to crack propagation and brittle fracture.For B series thin wall cylindrical shell, the failure modes were local buckling and the load capability decreased by 12.59%.Then, numerical analysis of cracked composite cylindrical shells under axial compression was developed by ABAQUS 6.14 using nonlinear algorithm RIKS.The Hashin failure criteria and damage evolution guidelines were introduced in the model to predict the progressive failure modes and the ultimate load.A good agreement was observed between numerical simulation and experimental results, and the maximum error was 7.01%.Furthermore, the effects of crack orientation and wind angle on the load capability of an axially loaded cracked cylindrical shell were studied.For cracked filament-wounded composite cylindrical shell with ±55° layer, the ultimate bearing capability increased first then decreased with the increasing crack orientation.The maximum limit load was got when α=45°.With the increase of wind angle ,the carrying capability showed a downward trend after the first rise for cylindrical shells with α=15°,45°,55° crack.And the wind angle had a more obvious influence on carrying capability with smaller crack orientation.The maximum limit load was got when θ=30°.