The flutter stability of the steel truss suspension bridge is hard to reach the requirement of the wind resisting stability when lacks the torsional stiffness.This paper discusses the influence of aerodynamic measure combination,such as central stabilizer,air director enclosed anti-collision bar and so on,towards the flutter stability of steel truss through the wind tunnel experiment of the bridge of Liu Jia gorge.The result shows:the effect of using both the upper and lower stabilized plate is better than separated used it.when sectionalized dispose upper stabilized plate,the flutter critical wind speed of attack angle will decrease rapidly.Outlaying the horizontal guide plate is better than internally installed; The flutter stability of different attack angle tend to be balanced by widening the horizontal guide plate.The anti-collision bar can be functionalized as the central stabilizer by heightening and enclosing,and effectively increase the critical wind speed of different attack angles of the high truss suspension bridge.

关键词：悬索桥；风洞试验；抗风措施；钢铁

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In August 2010, Midwest Roadside Safety Facility (MwRSF) developed and crash tested a low-cost, energy-absorbing bridge rail for the Manual for Assessing Safety Hardware (MASH) TL-3 applications. This low-cost bridge rail was designed to be compatible with the Midwest Guardrail System (MGS) such that an approach transition would not be required between the two barriers. It was desired that the system minimize bridge deck and rail costs. As part of this project, several concepts for an energy-absorbing bridge post were developed and tested. These concepts included strong-post systems designed with plastic hinges and weak-post systems designed to bend near the attachment to the bridge deck. The final post concept incorporated S3 OE 5.7 steel sections designed to yield at their bases. These posts were located on 6 ft-3 inches on center. A W-beam section was used as the rail element and was attached to the posts with a bolt designed to break during and impact event. Two full-scale crash tests were performed according to the TL-2 impact conditions provided in MASH. The new bridge rail system successfully met all the safety performance criteria for MASH TL-2. The Texas Type T631 Bridge Rail was developed as a low-cost, energy absorbing bridge rail system for TL-2 applications. Many of the features used for the system tested at Midwest Roadside Safety Facility for TL-3 were incorporated into the design developed for this project for MASH TL-2 application. The TxDOT Type T631 Bridge Rail designed and developed for this project was evaluated under MASH TL-2.

关键词：大桥护栏；碰撞测试；钢铁

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Based on node test and finite element analysis results of four different structural form enhanced nodes,failure modes,hysteretic behavior,bearing capacity,ductility and energy dissipation capacity of nodes are analyzed comprehensively and comparatively for more in-depth exploration about the seismic performance of symmetric enhanced nodes.The results showed that all the symmetric enhanced nodes have full hysteretic curve and energy dissipation capacity.On the whole,The flange-plate reinforced node exhibit better seismic performance.

关键词：钢框架；加强节点；循环加载试验；有限元分析

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High hard armor steels are used on many tactical vehicles, such as the Stryker and the mine-resistant, ambush-protected vehicle. Although they provide good protection against armor-piercing threats, these steels corrode rapidly without the use of a good corrosion protective coating. Corrosion on military ground vehicles increases the infrared signal from the vehicle that the topcoat camouflage usually inhibits, making the vehicle more vulnerable to detection by the enemy. Stryker vehicles are prohibited from using hex-chrome and are currently coated without any pretreatment or conversion coating. The products demonstrated here will satisfy the hexavalent chrome prohibition while minimizing environmental impact and worker safety. This demonstration plan is designed to generate the data necessary for authorization and implementation decisions by appropriate authorities within the U.S. Department of Defense.

关键词：护甲；腐蚀；六价铬；高硬度装甲腐蚀

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Based on the shape detecting principle and the digital signal technology,a new shape meter was developed thorough theoretical analysis and industrial adjustment to develop the shape detecting roll,the shape signal processing method,the original signal compensation mechanism and so on.The shape meter has good performance and stability,which can effectively avoid the scratchof steel strip surface,accurately detect real online strip shape and provide accurate online shape datum for shape control system.It was applied in 1250 mm cold rolling mill,the actual industrial tests prove that the shape signal was stable and reliable,met the harsh condition and the online technical requirements,and could improve shape quality significantly.

关键词：板形仪；形状检测；形状控制；冷轧带钢

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Iron is produced by the reduction of iron ore and other iron oxides as a precursor to steel and by remelting of metallic stock to produce a family of iron-based alloys (cast irons) for industrial use. More than 1 billion metric tons of iron is produced annually by reduction processes.1 Blast furnaces account for more than 90% of iron reduction with the rest accomplished through direct reduction or "alternate ironmaking" processes. Cupola furnaces, rotary furnaces, and induction furnaces are the primary units for cast iron re-melting. In 2009, the cast iron production of the main industrialized countries was 58.6 million metric tons. The role of oxygen combustion in reduction processes is described in Sections 21.2 and 21.3, and in re-melting processes in Section 21.4.

关键词：铁矿石；氧化铁；钢铁

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Austenitization is a solid-phase transformation process accompanied by nucleation and nucleus growth controlled by long-range carbon diffusion. In our work, a method was developed for constructing spheroidite model structures in such a way that their different parameters (the size of ferrite grains, the average value of carbon concentration, the size of cementite spheroids) could be changed optionally. In addition, a nucleation model of free energy base was created by which the difference between the two different places of nucleation can be distinguished on the basis of their free energy. The effects of structure parameters, interface free energies and temperature on the nucleation rate of austenite were investigated by cellular automaton simulations.

关键词：奥氏体化；成核速率；球状渗碳体；元胞自动机

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Using a 1984 benchmark experiment, MCNP6 replicated the neutron flux and neutron protection factor (NPF) measurements of an iron box, which simulated a basic military vehicle, resulting in less than 5% difference from the published results. Additionally, the neutron flux spectrum of a 239 PuBe source was characterized using a Bonner Sphere Spectrometer (BSS) and the solution unfolded using the Maximum Entropy Deconvolution (MAXED) program, producing a X2/df of 0.97. Utilizing a steel box provided by the DTRA, measurements of neutron flux from a D-D neutron accelerator were recorded via BSS inside and outside of the box. Both flux spectra were unfolded through MAXED using MCNP6 computations as a priori, which resulted in X2/df values of 0.86 and 0.91, respectively. NPF assessments of the steel box were then conducted using experimental and MCNP6 flux spectra for the box, as well as H*(10) scaling, with final results differing by less than 1%. MAXED software was leveraged for all flux spectrum unfolding, incorporating updated BSS response functions generated within this research from MCNP6. This experiment and its conclusions strongly support the verification and validation of MCNP6 for modeling NPF assessments of military vehicles.

关键词：中子通量；中子保护因子；中子能谱；钢铁

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The paper is focused on issues related to the behavior of reinforced soil walls at working stress and near failure, and the prediction accuracy of internal stability working stress and limit equilibrium (LE) design methods. The paper identifies the key variables, principles and assumptions that affect the accuracy of these methods considering the full range of conditions from working stress to failure. The strain at peak strength of a granular soil wall backfill is identified as a key parameter for understanding the differences between working stress and LE design methods. Both geosynthetic and steel reinforced wall systems are examined using measured reinforcement strain and loads taken from full-scale walls under both working stress (operational) conditions and at incipient collapse (failure).

关键词：工作压力；加筋土墙；钢铁

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In contrast to composite long rods, composite post insulators are subjected mainly to loads which act perpendicular to the longitudinal axis of the insulator and thus produce bending stresses over the cross-section of the insulator. These bending stresses reach their maximum value at the point at which the FRP rod is fixed in the metal fitting (circled in red in Fig. 3.1), the latter being located where the insulator is attached to the support structure, whether this be the cross-arm of a steel lattice tower for an overhead transmission line, the coupling plate of a tubular steel or concrete pole, or the platform in a pole-mounted substation. Calculation of these bending stresses is discussed in detail in Sect. 3.9.

关键词：复合长棒；绝缘体；钢铁

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