水下采油树钢结构焊接残余应力消除

本文根据中国南海某气田开发项目水下采油树的应用环境及应用要求 ,对水下采油树钢结构焊接所产生的残余应力的机理、分布规律及其影响因素进行了分析,并阐述了控制水下采油树钢结构焊接残余应力的主要工艺解决措施。此基础上,将其应用于国产化备用采油树项目,满足了产品的应用要求。     

Effect of residual stress on impact damage in a dissimilar laminated plate at a biaxial bending mode

Systematic investigations have been performed on the mechanisms that lead to impact damage in a dissimilar laminated plate with a thermal residual stress at a biaxial bending mode. Glass/polymer laminated plates are often used as blast-proof safety screens, and bullet-proof windows, and in windshields in the automotive and the aerospace and aeronautical fields. Their many advantages, the development of new materials, and the need for high-performance, low-weight structures ensure that laminated plate construction will continue to be in demand. In this work, the impact damage in glass/Al alloy laminated circular plates cured at RT and 80°C was investigated using an instrumented long bar impact tester at a biaxial bending mode. A circular plate was cured at different curing temperatures to form a thermally induced residual stress at the bonding interface. To improve the damage tolerance of laminated circular plates, various geometric (thickness ratio of the inner to outer layer) and material parameters are considered by determining their effects of maximizing impact absorbed energy. The measured impact force profiles and the impulse of the force explained the impact damage behaviors induced in the laminated circular plates. We show that a compressive residual stress could reduce the initiation of radial cracks and the impact damaged area of the laminated plate in the outer layer. Greater an inner layer thickness results in smaller a damaged area. A design guideline for effective dissimilar laminated plate construction is proposed.     

船舶结构强度直接计算中板单元应力的取法

以某油船外底加筋板为例,分析有限元计算中,板单元中面应力和表面应力的差别,说明衡准其强度时应该采用单元形心处的中面应力。     

混凝土组成成分对混凝土性能的影响

通过分析水泥品种、用量,粗骨料针片状含量、吸水率,砂的含泥量等混凝土组成成分的品质对混凝土强度、耐久性的影响,探讨从材料本身质量角度提高混凝土性能的基本措施。     

对混凝土构件强度无损检测若干问题的探讨

混凝土构件抗压强度检测是公路工程质量检测中的重要项目,通过对现行检测中相关规程、规范的对照分析,结合在实践检测工作中常见多发问题,提出了若干想法和建议。     

SMA路面在辽宁普通公路应用中材料技术要求研究

通过对SMA的强度原理分析以及对辽宁省普通公路SMA的材料技术要求的总结,指出影响SMA混合料性质的主要因素,并对影响因素进行了分析。     

水泥稳定砂砾力学性能探讨

水泥稳定砂砾基层由于其强度高、刚度大、板体性好、料源丰富等特点而被广泛采用,在级配相同的条件下,随水泥用量的增大,水泥稳定砂砾各龄期的强度增长幅度大致相等。     

某边梁式车架有限元静态分析

以某边梁式车架为研究对象,利用UG软件建立了三维实体模型,再使用HyperMesh软件进行了有限元静态分析,从而校核了该车架的强度和刚度,分析结果显示该车架的强度及刚度能够满足要求。     

转向节臂强度分析

本文利用传统的理论计算方法和有限元方法对某转向节臂强度分别进行分析,分析结果表明强度满足要求,从理论上验证了转向节臂设计的合理性,为设计提供了理论依据。     

摩托车车架有限元建模方法分析

对于不同摩托车车架的结构型式,相应的有限元计算模型有基于杆系结构的计算模型、基于板壳结构的计算模型及杆系、板壳混合结构的计算模型3种。杆系结构计算模型对车架实际结构简化过大,只能得到相对满意的整体结构强度和刚度;板壳结构计算模型比杆系结构计算精度高,是目前较先进的一种处理方法;对于管板组合式摩托车车架,可采用杆系和板壳组合结构进行计算。