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排序方式: 共有540条查询结果,搜索用时 31 毫秒
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In various engineering fields like aerospace and aircraft structures or marine and offshore platforms, constitutive material of critical components should be made of specific materials that can work properly in the required workspace. Such materials must have excellent properties such as high mechanical strength as well as great resistance to corrosion, oxidation, and creep. Inconel 625 is a superalloy that is chosen as constitutive material of critical components due to its great abilities. On the other hand, since investigating Inconel 625 pipe has not been done yet, different mechanical characteristics of using structures made of Inconel 625 should be assessed. Additionally, doing so would be necessary to gather information for current industrial affairs and also future investigations. Therefore, the nonlinear dynamic instability response of axially loaded Inconel 625 pipes is investigated in the current article. The pipe structure is modeled via the Donnell shell theory and nonlinear von Kármán theory. The motion equations of pipes are established by applying the Hamiltonian approach. Then, in order to alter the nonlinear derived partial differential equations into the Mathieu-Hill equation, both Navier's solution and Airy stress function are implemented. Additionally, the amplitudes of steady-state oscillation of the Inconel 625 pipe are determined by employing Bolotin's method. Eventually, the impacts of various effective parameters on the nonlinear dynamic behaviors of Inconel 625 pipes are evaluated. The results indicate static and dynamic load factors possess a remarkable effect on instability exciting areas and steady-state vibration amplitudes of pipe. Moreover, the dynamic instability response of the pipe is dependent on the radius-to-thickness and length-to-radius ratios, and also how the ratios are affected depends on the wave number. 相似文献
536.
为研究塑性混凝土防渗体系在高水头差船闸施工土石围堰中应用时,其渗透坡降、应力应变及围堰填筑材料、所处地层渗透系数对防渗墙渗透坡降的影响机理,结合万安二线船闸工程中应用的土石围堰监测结果,对塑性混凝土防渗墙的应力、应变进行有限元计算分析。采用不同的本构模型对土石围堰不同填筑区的填筑料进行模拟,结果表明:塑性防渗墙具有良好地防渗降压作用,所起作用的大小与围堰填筑材料及地层的渗透系数有关。应变监测结果表明,防渗墙在工作阶段主要受压应力作用,压应变值为-247.8×10-6~0,处于-750×10-6~100×10-6允许应变范围,确保了防渗墙在工作阶段的安全可靠。 相似文献
537.
土工合成材料在黄骅港的应用 总被引:2,自引:2,他引:0
介绍黄骅港工程中土工合成材料的应用情况,并根据现场断面监测结果,分析土工织物加筋垫层的作用效果和塑料排水板对堆场软土地基的加固效果。 相似文献
538.
基于近年来上海地区河道整治工程中塑钢板桩的应用案例,并通过塑钢板桩与其他常见的护岸型式在生产、施工、滤水护坡、后期维护、工程造价等方面进行对比,可以发现,高强度塑钢板桩具有较强的拉伸、抗弯强度,且有较强的抗冲击和柔韧性,材质稳定、坚固耐久、不腐蚀、不蚁驻、不开裂,有较高的抗压强度和抗冲击能力。材料成分稳定,不受气候水质影响,同时产品无有毒有害物质成分,对水土环境绝不产生污染,绿色环保可循环,能符合国家绿色建筑的工程需求。基于塑钢板桩的特点提出优化建议,有助于塑钢板桩在今后的工程中能更好地被应用。 相似文献
539.
塑料管道以其良好的耐腐蚀性及防渗性能在市政排水中运用得越来越广泛。但由于塑料管道的结构计算为管土共同作用,相对于其它刚性管道较为特殊,考虑因素较多,且无图集可供选用,导致很多设计人员对塑料管道的选用无从下手,很难分清影响管道安全的主要因素。现通过大量的计算对塑料管道适用覆土范围进行总结,并提出选用应考虑的主要因素,以方便设计人员在保证结构安全的前提下,经济合理地选用塑料管道。 相似文献
540.
[Objectives]As composite materials have varied internal structures, an in-depth analysis of the damage mechanisms of their component materials can provide a research foundation for the ultimate strength analysis of composite stiffened panels. [Methods]The microscopic, mesoscopic and macroscopic mechanical analyses of marine glass fiber reinforced plastic (GFRP) composite stiffened panels are carried out using a multi-scale approach. Microscopic and mesoscopic representative volume element (RVE) models of chopped strand mat (CSM) and woven roving (WR) materials are established, and the macroscopic equivalent stiffness is obtained by homogenizing the RVE models. The ABAQUS VUMAT subroutine is used to code the progressive damage evolution model of the composite materials to derive the damage evolution mechanism of the microscopic and mesoscopic models respectively. The equivalent strength of macroscopic laminates is also obtained. [Results]The multi-scale approach can be used to accurately evaluate the macroscopic mechanical properties of composite materials, and the ultimate strength of composite stiffened panels is mainly determined by fiber bundle failure. [Conclusions]The obtained macroscopic material parameters can be used to calculate the ultimate strength of composite stiffened panels, while the parametric study of the mesomechanics of composite materials can provide an analysis tool for investigating the influence of material processing technology. © 2023 Chinese Journal of Ship Research. All rights reserved. 相似文献