Influence of interfacial strength on the fracture toughness of glass-ceramic matrix composites

Nine kinds of glass-ceramic matrix composites with different compositions and interfacial strength (τ _s) were prepared. The influence of τ _s on the fracture toughness(K _1c) of composites was studied. It was discoved that, for the system no chemical reaction taking place at the interface, K _1c increased proportionally with τ _s increasing at the first stage, then decreased when τ _s reached a certain value. According to this result, a model of relationship between τ _s, thermal mismatch (Δα _r) and K _1c was built up. If a chemical reaction took place and a new phase was formed in the interface, the K _1c of composite was effected by the combination of τ _s, chemical bonding, radial interfacial stress and other factors. Project supported by the National Natural Science Foundation of China Synopsis of the first author Wang Lingsen, professor, born in 1938, current research field: special ceramic and ceramic matrix composite, etc.     

钢筋混凝土环形截面构件受弯时强度计算

空心圆形电柱在安装时可能受到弯曲作用，其强度计算，是在做了合理假定后推导力学方程式。求解方程式并非易事，即使使用计算机也只是试算求解，或采用图解法。本文给出求解联立方程组的计算方法。     

剪力环对钢管混凝土粘结强度影响的试验

通过对3根设置剪力环，3根不设剪力环，直径相同、厚度相同的试件进行研究，分析了钢管与混凝土之间的粘结性能、破坏机理，探究了影响其强度的主要因素．     

Advances in micro assembly injection moulding for use in medical systems

In micro systems technology, the process of micro assembly injection moulding is used for the generation of hybrid micro systems. With this process, more functions are integrated in less space. In the field of medical technology, miniaturisation also means new methods of treatment with fewer side effects on the patient. New cures are developed by the miniaturisation of medical instruments, such as keyhole surgery. For detailed investigations a specific demonstration was developed to display the potential of micro assembly injection moulding in medical science. This part consists of a carbon-fibre reinforced PEEK puncture needle, which incorporates three lumens. The selected materials allow use of the needle during magnetic resonance imaging. In order to attach additional equipment a plastic connector needs to be overmoulded on the needle. The investigations focus on the injection moulding process by characterising the influences of temperature, moulding parameters and material combinations on the resulting bond strength between needle and connector.     

三点弯曲试件塑性转动因子的试验研究

通过试验及理论分析,讨论了屈服强度对三点弯曲试件塑性转动因子的影响．试验结果表明：随着屈服强度的增加,塑性转动因子增大．     

钢筋混凝土简支深梁受剪承载力的极限分析

本文讨论了钢筋混凝土简支深梁的剪切破坏形态和主要影响因素,假定钢筋和混凝土均为刚塑性材料,引用混凝土双向受压的破坏条件,求出了集中和均布荷载作用下钢筋混凝土简支深梁受剪承载力的塑性解。根据试验结果给出了考虑混凝土强度和剪跨比影响的深梁混凝土塑性有效抗压系数,所获得的理论公式与国内外试验结果符合良好。     

絮凝体的物理特性

从絮凝体的密度,空隙率、絮凝体的粒径分布,絮凝体的强度以及絮凝体的分形维数五个方面综述了絮凝体的物理特性及结构特性,分析了影响絮凝体物理特性的因素。     

聚脲改性聚酰胺多胺环氧氯丙烷涂布抗水剂的研究

制备了高含固量，稳定性好的聚脲改性聚酰胺多胺环氧氯丙烷，通过实验研究了其作为涂布抗水剂的应用工艺及作用机理，分析了多种因素对产品性能和贮存稳定性的影响。     

环口板加固T型方钢管节点在轴压作用下极限承载力的参数分析

为了研究环口板加固对T型方钢管节点在支管承受轴向压力作用下的极限承载力的影响,本文运用前期工作中所采用的有限元模型建立方法,对320个环口板加固T型方钢管节点进行了参数分析。参数包括支管和主管的宽度比β,主管的宽度与厚度比2γ,环口板与主管厚度比τc和环口板与支管宽度比lc/d1。参数分析结果表明:通过对环口板的宽度和厚度进行适当的组合,可以显著提高节点的承载力。然后将有限元模拟得到的极限承载力结果与前期工作中推导出的极限承载力公式的计算结果进行对比,给出了极限承载力计算公式的适用范围。