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891.
892.
现浇钢筋混凝土高强薄壁箱体空心板是一种新型的钢筋混凝土空心结构.进行了高强薄壁箱体简支板的有限元分析,以掌握其受力性能,并考察高强薄壁箱体对结构性能的影响.研究表明,高强薄壁箱体与混凝土粘结紧密牢靠,高强薄壁箱体空心板整体性良好,且高强薄壁箱体的存在提高了结构的刚度,使高强薄壁箱体楼盖有具有良好的使用性能. 相似文献
893.
The stress combination method for the fatigue assessment of the hatch corner of a bulk carrier was investigated based on equivalent waves.The principles of the equivalent waves of ship structures were given,including the determination of the dominant load parameter,heading,frequency,and amplitude of the equivalent regular waves.The dominant load parameters of the hatch corner of a bulk carrier were identified by the structural stress response analysis,and then a series of equivalent regular waves were defined based on these parameters.A combination method of the structural stress ranges under the different equivalent waves was developed for the fatigue analysis.The combination factors were obtained by least square regression analysis with the stress ranges derived from spectral fatigue analysis as the target value.The proposed method was applied to the hatch corner of another bulk carrier as an example.This shows that the results from the equivalent wave approach agree well with those from the spectral fatigue analysis.The workload is reduced substantially.This method can be referenced in the fatigue assessment of the hatch corner of a bulk carrier. 相似文献
894.
“东方二号”放缆平台结构强度有限元分析 总被引:1,自引:1,他引:0
“东方二号”勘探船由于实际使用需要,在船尾方向加设一个平台结构供放缆用.由于平台结构需要拖拽测量仪器和承受设备重量,所以需要对平台及相连主船体结构强度进行有限元方法计算分析.本文对放缆平台在实际使用中可能遇到的3种工况进行分析,并得出计算结果.通过数据结果,可以对放缆结构的抗弯、抗剪等强度具有整体的认识和局部细节的把握.结果还表明,平台结构端部及附近区域船体结构强度的等效应力,弯曲和剪切强度均符合规范要求.最后,还对结构提出了优化设计建议. 相似文献
895.
896.
为准确分析二冲程船舶柴油机工作时曲轴的动态特性,结合Pro/E 3D软件和ANSYS软件对船舶柴油机曲轴、轴承、活塞、连杆等部件进行三维实体有限元建模,采用子结构法对其进行结构缩减,并将结果文件导入EXCITE软件中,建立整个船舶柴油机的轴系非线性多体动力学模型。采用该模型对曲轴进行一个循环的多体动力学计算。将计算结果恢复到曲轴实体有限元精细模型,进行正常工况下曲轴在一个循环内的动应力计算。结果表明,与单体曲轴强度分析方法相比,采用非线性多体动力学方法可获得更接近实际的曲轴载荷的边界条件,提高了船舶柴油机曲轴动态特性计算精度。 相似文献
897.
The dynamic buckling of the main deck grillage would result in the total collapse of the ship hull subjected to a far-filed underwater explosion. This dynamic buckling is mainly due to the dynamic moment of the ship hull when the ship hull experiences a sudden movement under impact load from the explosion. In order to investigate the ultimate strength of a typical deck grillage under quasi-static and dynamic in-plane compressive load, a structure model, in which the real constrained condition of the deck grillage was taken into consideration, was designed and manufactured. The quasi-static ultimate strength and damage mode of the deck grillage under in-plane compressive load was experimentally investigated. The Finite Element Method (FEM) was employed to predict the ultimate strength of the deck grillage subjected to quasi-static in-plane compressive load, and was validated by comparing the results from experimental tests and numerical simulations. In addition, the numerical simulations of dynamic buckling of the same model under in-plane impact load was performed, in which the influences of the load amplitude and the frequency of dynamic impact load, as well as the initial stress and deflection induced by wave load on the ultimate strength and failure mode were investigated. The results show that the dynamic buckling mode is quite different from the failure mode of the structure subjected to quasi-static in-plane compressive load. The displacements of deck edge in the vertical direction and the axial displacements are getting larger with the decrease of impact frequency. Besides, it is found that the dynamic buckling strength roughly linearly decreased with the increase of initial proportion of the static ultimate strength P0. The conclusions drawn from the researches of this paper would help better designing of the ship structure under impact loads. 相似文献
898.
以45 m混凝土泵车为研究对象,利用ANSYS有限元软件,采用实体单元与接触单元相结合的方法模拟各个臂架之间的连接,用板壳单元和梁单元模拟泵车其余结构,建立了整车有限元模型.分析泵车在3种典型工况下的结构强度,发现混凝土泵车臂架在危险工况局部结构强度不能满足设计要求,通过计算分析提出了结构补强方案.改进后的结构实际使用情况良好. 相似文献
899.
900.