新型预制柱H型钢梁肋板式节点受力性能分析

金凤城市中心1#楼采用了预制柱的混凝土框架结构体系，部分长悬臂梁采用了H型钢梁。对比了H型钢梁与混凝土柱的常用节点形式，提出了一种混凝土柱和H型钢梁刚性连接的肋板式新型节点形式。采用有限元软件对节点进行了梁截面宽度、水平肋板宽度、预埋板厚度、栓钉数量的参数化分析，得出钢梁截面宽度对节点与梁线刚度比影响最大、水平肋板宽度影响其次、预埋板厚度影响次之、栓钉数量及布置影响较小的结论。对应用在本工程中的典型节点进行了强度、刚性分析，验证了该节点形式的安全可靠。     

基于双模量理论的高强度钢环肋圆柱壳 总体稳定性塑性修正方法

文章基于矩形截面压杆的双模量理论和高强度钢的材料弹塑性本构关系,建立了环肋圆柱壳结构总体稳定性塑性修正曲线及修正方法,结果表明,模型的计算结果与静水外压试验测得的塑性失稳压力值及有限元结果符合情况较好,压杆双模量理论模型虽然和环肋圆柱壳实际结构存在差异,但由此得到的塑性修正方法仍具有较好的工程精度,在应用于高强度钢环肋圆柱壳总体稳定性计算时适应性好,且形式简单,便于运用。     

双层水平板式防波堤结构箱型水平板研究

双层水平板式防波堤是一种新型的水工结构物,采用上下两层水平板达到消浪、透水的目的.本文研究的水平板采用钢制箱型板结构.根据物理模型试验测定的波浪荷载,应用ANSYS有限元软件,分别探讨不同支承形式、钢板厚度、H型钢加劲肋个数和型号等因素对水平板应力和变形的影响,并与传统计算方法相比较,为双层水平板式防波堤的结构设计及工程应用提供参考.     

斜拉桥钢-混组合箱梁焊钉连接件剪力分布研究

由槽型钢梁和混凝土桥面板组成的组合箱梁是一种较为新型的结构形式,已在大中跨径斜拉桥中得到应用。焊钉连接件对组合梁的力学性能有很大影响。文中以国内某槽型钢结构-混凝土板组合箱梁斜拉桥为工程背景,建立包含子结构的空间有限元模型,计算组合梁中焊钉连接件在各种荷载作用下的受力情况,分析焊钉纵、横桥向剪力分布规律。计算结果表明组合梁的钢-混连接面上的剪力分布不均匀,在中跨跨中位置较小,边跨辅助墩和边墩附近较大;恒载是引起剪力的主要因素,混凝土桥面板的收缩对其影响也较大。     

环肋圆柱壳在水下爆炸冲击下的响应

针对水下非接触爆炸问题过程复杂、计算速度慢的问题,本文以一环肋圆柱壳为例,基于以内嵌的水下爆炸载荷计算方法和声-结构耦合方法为关键技术的水下爆炸分析法(AUA),对其水下爆炸冲击下的响应进行了分析。结果发现,壳板厚度对圆柱壳的水下非接触爆炸响应有较为显著的影响,随着壳板厚度的增加,环肋圆柱壳最大位移减小的幅度逐渐变小。在爆炸初期爆距对环肋圆柱壳冲击响应的影响不大,随时间的推移这种影响逐渐增大,环肋圆柱壳各测点变形随爆距的增大线性减小;当肋骨间距大于0.25倍环肋圆柱壳长时,环肋圆柱壳最大变形量可减小90%;继续减小肋骨间距,环肋圆柱壳最大变形减少量并不明显,说明肋骨对其附近测点和中间的板壳起到了显著的加强作用,肋骨间距为0.25倍环肋圆柱壳长时为最经济的肋骨布置方式。     

环肋圆柱壳在水下爆炸冲击下的响应

针对水下非接触爆炸问题过程复杂、计算速度慢的问题,本文以一环肋圆柱壳为例,基于以内嵌的水下爆炸载荷计算方法和声-结构耦合方法为关键技术的水下爆炸分析法(AUA),对其水下爆炸冲击下的响应进行了分析。结果发现,壳板厚度对圆柱壳的水下非接触爆炸响应有较为显著的影响,随着壳板厚度的增加,环肋圆柱壳最大位移减小的幅度逐渐变小。在爆炸初期爆距对环肋圆柱壳冲击响应的影响不大,随时间的推移这种影响逐渐增大,环肋圆柱壳各测点变形随爆距的增大线性减小;当肋骨间距大于0.25倍环肋圆柱壳长时,环肋圆柱壳最大变形量可减小90%;继续减小肋骨间距,环肋圆柱壳最大变形减少量并不明显,说明肋骨对其附近测点和中间的板壳起到了显著的加强作用,肋骨间距为0.25倍环肋圆柱壳长时为最经济的肋骨布置方式。     

多钉剪力连接件非线性有限元分析

运用ABAQUS软件对多钉剪力连接件推出试验进行非线性有限元分析,并把计算结果与推出试验的结果进行对比研究,分析过程中考虑了结构的几何非线性和材料非线性,并引入了混凝土损伤的影响.研究结果表明,非线性有限元计算的结果与推出试验结果吻合较好,有限元方法能够较好地模拟焊钉推出试验,可以作为一种便捷的研究手段.焊钉间距对焊钉抗剪承载力影响较小,焊钉的根部受力和变形最大,从焊钉根部向焊钉端部方向,应力和变形逐渐减小.推出试验破坏形式为焊钉根部被剪断,并且焊钉根部下方混凝土被压碎.破坏时上排焊钉变形较大,首先被剪断,然后发生剪力重分配,导致下排焊钉被迅速剪断,下排焊钉变形比上排焊钉变形小.     

多蛋形交接耐压壳屈曲特性试验与数值研究

文章研究了多蛋形交接耐压壳屈曲行为。基于壳体开孔处的变形量与完整壳体一致的设计理念,优选多蛋壳结构参数,制作多蛋壳比例模型,并对其制作误差进行了检测。此外,还进行了静水压力试验,验证真实多蛋壳破坏形式,检验环肋参数的合理性,比较了考虑真实形状和厚度的非线性有限元分析结果。结果表明:基于变形协调理念设计的多蛋壳,最终破坏远离环肋交接处,蛋形壳单元破坏形式及载荷与完整单蛋壳基本相同,试验验证了多蛋壳继承了完整蛋形壳较好的耐压特性;基于弧长法的数值计算与试验结果具有良好一致性,考虑真实形状和厚度的非线性有限元分析可用于分析预测真实壳体的屈曲特性。     

加环肋圆筒形薄壳在静水外压下的总体大挠度塑性稳定性及初挠度对其影响

本文将加环肋圆筒形薄壳按Flugge方法视为正交异性壳,把流动理论和变形理论化成类似形式,用能量法讨论了加环肋圆筒形薄壳在静水外压下的总体大挠度塑性稳定性和初挠度对其临界压力的影响。给出了临界荷重计算方法。进行了数字计算。理论计算值和试验结果吻合较好。     

济南建邦黄河大桥主桥设计

济南建邦黄河大桥主桥采用主跨2×300m三塔预应力混凝土梁斜拉桥。中塔处为塔梁墩固结,边塔塔柱通过箱梁时,箱梁形成开口截面,从而主塔与塔墩固结,形成中塔固结,边塔半漂浮的体系;主梁采用单箱四室斜腹板截面,桥宽30.5m,标准索距梁段均设有横梁及横向加劲肋板;中塔柱为纵向人字型结构,边塔柱采用独柱式结构;斜拉索采用镀锌平行钢丝拉索;基础采用钻孔灌注桩基础。大桥在桥式布置、主梁、主塔构造设计等方面具有一定的技术突破与创新。     

Compressive tests on short continuous panels

Results of eight tests on stiffened panels under axial compression until collapse and beyond are presented. The tests consider panels with different combinations of mechanical material properties and geometric configurations for the stiffeners including the use of ‘U’-shaped stiffeners. The specimens are three bay panels with associated plate made of high tensile steel S690. Four different configurations are considered for the stiffeners that are made of mild or high tensile steel for bar stiffeners and mild steel for ‘L’ and ‘U’ stiffeners. The influence of the stiffener's geometry on the ultimate strength of the stiffened panels under compression is analyzed.     

Evaluation of ultimate strength of stiffened panels under longitudinal thrust

A series of collapse analyses is performed applying nonlinear FEM on stiffened panels subjected to longitudinal thrust. MSC.Marc is used. Numbers, types and sizes of stiffeners are varied and so slenderness ratio as well as aspect ratio of local panels partitioned by stiffeners keeping the spacing between adjacent longitudinal stiffeners the same. Initial deflection of a thin-horse mode is imposed on local panels and that of flexural buckling and tripping modes on stiffeners to represent actual initial deflection in stiffened panels in ship structures. On the basis of the calculated results, buckling/plastic collapse behaviour of stiffened panels under longitudinal thrust is investigated. The calculated ultimate strength are compared with those obtained by applying several existing methods such as CSR for bulk carriers and PULS. Simple formulas for stiffened panels, of which collapse is dominated fundamentally by the collapse of local panels between longitudinal stiffeners, are also examined if they accurately estimate the ultimate strength. Through comparison of the estimated results with the FEM results, it has been concluded that PULS and modified FYH formulas fundamentally give good estimation of the ultimate strength of stiffened panels under longitudinal thrust.     

Experimental study on the collapse strength of wide stiffened panels

Five specimens are tested under axial compression until collapse to investigate the ultimate strength of wide stiffened panels with four stiffeners. To avoid the side bays collapse and reduce the influence of the clamped boundary condition on the collapse behaviour, the tests are made on panels with two half bays plus one full bay in the longitudinal direction with simply supported condition at the end edge of loading. Initial loading cycles are used to release the residual stresses of the stiffened panels and the gap between the stiffened panels and the supported steel block. Strain gauges are installed on the plates and the stiffeners to record the distribution of strain. This series of experiments is compared to a series of tests with narrow panels (two stiffeners), which allows analysing the effect of the width on the strength of stiffened panels.     

圆钢管混凝土柱低周反复加载试验研究

为了研究钢管混凝土柱在低周反复荷载作用下组合材料横截面刚度对其性能的影响,以果园港二期工程上的钢管混凝土柱为原型,对3根钢管混凝土柱进行低周反复加载试验。通过控制试件钢管厚度进行物理模型试验,研究钢管厚度对钢管混凝土柱耗能性能、承载性能、强度退化、刚度退化、延性和变形能力的影响。试验结果表明:随着试件钢管厚度的增加,试件的能量耗散系数与等效黏滞阻尼系数均随之减小,试件的耗能能力随之变弱;钢管厚度越小,钢管混凝土柱试件的耗能性能越好。钢管越厚,对核心混凝土的约束作用就越强,强度退化就越弱,试件塑性变形能力就越好。钢管越厚,外包钢管对核心混凝土约束作用就越强,水平承载能力越高。     

Test of extensively damaged hybrid ship hull

A hybrid ship hull model made with a steel truss and composite sandwich panels was tested and analyzed with the goal of gaining insight into how well this structural concept holds up after major damage. One of the ideas of the concept was to mount the sandwich panels to the steel truss such that they can be blown out in a controlled fashion to ventilate a large internal blast. The hull should be designed to have sufficient strength for the ship to reach a port safely even after such extensive damage. A 6-m model of such a hybrid ship hull, consisting of a stainless steel truss and 60 composite sandwich panels, was manufactured and mechanically tested. A number of panels were then removed one by one and the hull was retested to the design load after each panel had been removed. The removed panels simulated major damage. After nine panels had been removed, from all the different areas of the hull, it could still carry the design load, although with considerable nonreversible deformations of the hull girder. The hull was eventually loaded to final failure, which occurred at 25% above the design load.     

The application of reliability methods in the design of tophat stiffened composite panels under in-plane loading

Composite materials have been widely used in modern engineering fields such as aircraft, space and marine structures due to their high strength-to-weight and stiffness-to-weight ratios. However, structural efficiency gained through the adoption of composite materials can only be guaranteed by understanding the influence of production upon as-designed performance. In particular, topologies that are challenging to production including panels stiffened with pi or tophat stiffeners dominate many engineering applications and often observe complex loading. The design of stiffened composite panels against buckling is a key point of composite structures. While a growing number of studies are related to the reliability analysis of composites few of these relate to the local analysis of more complicated structures. Furthermore for the assessment of these structures in a design environment it is important to have models that allow the rapid assessment of the reliability of these local structures. This paper explores the use of a stochastic approach to the design of stiffened composite panels for which typical applications can be found in composite ship structures. A parametric study is conducted using Navier grillage theory and First-order Reliability Methods to investigate any detectable trend in the safety index with various design parameters. Finally, recommendations are made to provide guidance on applications.     

Bond-slip behaviour of concrete filled double skin steel tubular (CFDST) columns

This paper provides novel results and key findings for the bond-slip field since there is no single study available in the literature conducted on the bond-slip behaviour of concrete filled double skin steel tubular (CFDST) columns. Likewise, no studies have been focused on the contribution of welded reinforcing bars on the bond behaviour of composite columns. A series of push-out tests on sixteen specimens of CFDST columns are presented to explore the bond-slip behaviour between the cross-sectional elements (the inner steel tube, outer steel tube and the shell concrete). The primary test parameters involve (a) interface type (normal interface, interface with an internal ring, with reinforcing bars, and with shear studs); (b) concrete strength (high strength concrete and normal strength concrete); (c) push-out type (push-out of the shell concrete and push-out of the inner tube). The results demonstrated that greater benefits arose on the bond strength, once the reinforcing bars or internal rings were welded onto the inner steel tube of CFDST columns. Moreover, in addition to remarkably improving the bond strength, the welded reinforcement bars would significantly improve the compressive strength of CFDST columns and eliminate the local buckling of the inner steel tube. On the other hand, the embedded shear studs (bolts) onto inner steel tubes are capable of improving the bond strength with less degree of the shear resistance in comparison with the other interface types. What's more, the current paper is also adapted to explore the influence of concrete grade (normal and high strength) on the bond performance of CFDST columns and it is showed that the bond strength increases considerably as the strength of the shell concrete is increased. Finally, the bond improvement ratio (BIR) is studied which could be a representative index in comparing the performances of the parameters on the bond behaviour.     

不同扶强材形式的纵骨贯穿舱壁结构疲劳试验

为了研究矩形扶强材和削斜扶强材结构形式的某铝合金船体纵骨贯穿舱壁结构疲劳性能，对此进行了试验研究。首先建立舱段结构的有限元模型（该目标船纵骨采用6082铝合金，其他部分采用5083铝合金材料），确定载荷工况并计算分析两种扶强材结构在相应载荷水平下的应力分布状态。在此基础上，设计并开展了实际板厚四点弯曲疲劳模型试验，获得了试验模型在不同载荷水平下的疲劳失效循环次数，并且根据试验测得数据得到了两种扶强结构形式的S-N曲线。试验结果表明矩形扶强材形式的纵骨贯穿舱壁结构疲劳性能优于削斜扶强材形式，该结论可为舰船上纵骨贯穿舱壁结构处节点形式的设计以及5083与6082铝合金焊接结构形式（T型焊接和趾端焊接）的疲劳强度评估提供依据。     

基于ALE算法的无转角和有转角铝制加筋板楔形体水弹性砰击的数值模拟研究

文章采用基于任意拉格朗日—欧拉(ALE)算法的显式有限元技术研究水弹性砰击现象,针对已开展的铝制加筋板楔形体结构入水砰击模型实验,开展了数值模拟比较工作。该楔形体底部斜升角为20度,底部两侧是包含三根纵骨和两根横梁的加筋板结构,两侧结构刚度不同。预报了模型无转角和有转角典型工况的砰击入水过程,得到的入水加速度、底部加筋板结构纵骨应力和横梁响应与模型实验结果吻合较好。研究表明该ALE算法具备模拟船舶局部结构的水弹性砰击流固耦合问题的能力。     

Comparisons of calculations with experiments on the ultimate strength of wide stiffened panels

Five specimens of wide stiffened panel with four stiffeners under axial compression until collapse are studied with a nonlinear finite element analysis and Common Structural Rules to compare with the experimental results. The stiffened panel models have two longitudinal bays to produce reasonable boundary condition at the end of edges. Tension tests have been conducted to obtain the material properties of the steel that are used in the finite element analysis. Three boundary condition configurations are adopted to investigate their influence on the collapse behaviour of the stiffened panels. A displacement transducer was used to measure the initial geometrical imperfections of the stiffened plates. The collapse behaviour of the stiffened panels is analysed in finite element analysis with the measured initial imperfections and with nominal imperfections. An equivalent initial imperfection is validated for the ultimate strength of stiffened panel under compressive load until collapse for the panels under consideration. With the same imperfection amplitude, the shape of the column-type initial deflection of stiffeners affects significantly the collapse shape, but only slightly the ultimate strength and the mode of collapse of the stiffened panels. The 1/2 + 1 + 1/2 bays model with restrained boundary condition BC3 gives an adequate FE modelling and is possible to be fabricated in experiment.