预应力混凝土在超长大面积地下室底板中的应用研究

预应力混凝土从本质上改善了钢筋混凝土构件的性能,相对于普通混凝土,预应力混凝土技术在地下室底板中的应用有其自身的特点,作者就预应力技术在超长大面积地下室底板工程中的应用进行了探讨.     

压型钢板-混凝土组合板的组合效应分析

压型钢板-混凝土组合板构件中,压型钢板和混凝土的组合效应体现了两者之间共同工作的程度,也体现了构件的抗剪强度。为了研究工程中各种组合板的组合效应,提出了组合效应系数的概念,并通过对试验资料的分析,提出组合效应系数的计算式,根据计算结果初步判断组合板构件的破坏形态。现在用两个试验对算式进行验证,结果基本相符。     

电磁搅拌对包钢板坯等轴晶率的影响

文章主要对包钢宽厚板坯连铸机采用二冷区电磁搅拌后,不同电磁搅拌参数对板坯中心等轴晶率的影响进行了分析。生产实践表明:当连铸工艺相同时,随着搅拌电流、搅拌频率的增大,板坯的中心等轴晶率平均增加了20%。     

闭口压型钢板-轻骨料屋面板抗弯试验研究

结合闭口压型钢板-轻质混凝土组合板的应用现状,阐述了该新型屋面结构的优点,通过试验对其抗弯刚度性能进行了研究,并总结了抗弯刚度的理论计算公式,得出计算结果与实测值吻合较好的结论.     

面板堆石坝分离式面板应力变形特性研究

为进一步研究分离式面板的技术特点,利用商业有限元分析软件ABAQUS分别对分离式和连续式面板堆石坝进行数值模拟,对满蓄期连续式面板和分离式面板的应力应变状态进行了对比分析。计算结果表明,相比于连续式面板,分离式素混凝土面板技术的应用改善了面板在满蓄期的应力分布状况,提高了混凝土面板对堆石体变形的适应能力;不同水平缝宽度对面板的整体应力应变状态影响较小,为避免局部应力过大而导致的混凝土挤压破坏,其宽度应根据变形计算进行确定。     

闭口式压型钢板-混凝土组合楼板受剪承载力试验研究

进行了 6块闭口型组合楼板的受剪试验 ,获得了其斜截面抗剪承载力及破坏形式 ,提出了这种组合板斜截面抗剪承载能力的简化计算公式 ,供工程设计时参考。试验结果与计算值的比较表明 ,简化计算公式能较合理地估算这种闭口型组合楼板的抗剪承载力     

Designing cold-formed steel sheets for composite slabs: An experimentally validated FEM approach to slip failure mechanics

The aim is to understand the steel–concrete slip mechanisms and its dependence on geometrical and physical parameters, in order to improve designs for steel decking for composite slabs. A new methodology to build 3D non-linear FEM models has been developed to simulate the longitudinal slip mechanics of composite slabs in “pull-out” tests. Sensibility of shear resistance is analysed in relation to: friction coefficient, embossing depth and slope, sheet thickness, inclination, length, width and spacing of embossments and profiling angle of rib shape. A new steel sheet design has been developed and optimised. On the other hand, several pull-out tests as well as reduced “m–k” shear-bond bending tests have been carried out in order to corroborate and validate FEM results, as well as to evaluate some other aspects. This paper summarizes the conclusions regarding to design recommendations and general slip behaviour matters. Several parameters, such as the embossing slope, the retention angle, the surface friction conditions, etc., have shown to be very significant in slip resistance.     

焊接钢筋网单向板开裂性能的研究

给出了焊接钢筋网单向板裂缝间距和宽度的计算公式，并做了７块单向板的试验来验证，结果表明，这些板的开裂间距主要依赖于焊接横向钢筋间距，而裂缝宽度的计算是根据裂缝间距进行的。     

Multiple scattering of shear waves and dynamic stress from a circular cavity buried in a semi-infinite slab of functionally graded materials

Based on the theory of elastodynamics and employing image method, the multiple scattering and dynamic stress in a semi-infinite slab of functionally graded materials with a circular cavity are investigated. The analytical solution of this problem is derived, and the numerical solutions of the dynamic stress concentration factor around the cavity are also presented. The effects of the distance between the cavity and the boundaries of the semi-infinite slab, the incident wave number and the non-homogeneity parameter of materials on the dynamic stress concentration factors are analyzed. Analyses show that the dynamic stress around the cavity increases with increasing non-homogeneity parameter of materials and incident wave number. The boundaries of the semi-infinite slab have great effect on both the maximum dynamic stress and the distribution of dynamic stress around the circular cavity, and the effect increases with increasing incident wave number.     

SP预应力空心板结构性能研究

依据我国现行规范,对高效预应力混凝土空心板SP板的结构性能作了系统全面的研究和大量计算,与美国PCI Manual for the Design of Hollow Core Slabs的结果和国内设计研究单位的研究结果进行了比较;同时进行了试验研究,以寻找合理的设计原则,更深刻地认识SP板抗弯、抗剪性能,破坏形态,开裂荷载以及板端钢绞线锚固的性能,同时对极端与砌体连接构造措施进行了研究.综合研究结果,制定了高效预应力空心板的设计技术条件,编制了SP板国标图集.