In construction stage, a large buffeting response would endanger construction safety and quality for a long span concrete-filled steel tube (CFST) arch bridge. Developing the study on buffeting security is indispensable to CFST arch bridge in construction stage. Combining random vibration analysis of structure with modern probability theory, taking an actual large span CFST arch bridge as example, dynamic reliability of buffeting responses research and analysis is developed, which is based on the buffeting analysis on time domain at the longest cantilever construction stage. The paper gives quantitative valuation on wind-vibration safety performance of the bridge in construction phase and offers a new thought and reference for homologous project.

关键词：钢铁;钢管混凝土管;拱桥;施工阶段

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关键词：钢铁；钢管；防腐；排水

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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：钢铁；工作压力；极限平衡；钢筋

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The paper is focused on key points and lessons learned from LRFD calibration of simple limit state functions for the internal stability of metallic reinforced soil walls. The example used in the paper is the ultimate pullout limit state for ribbed steel strip reinforced mechanical stabilized earth (MSE) walls and a single load due to soil self-weight plus a permanent surcharge load. The paper demonstrates how load and resistance measurements from instrumented walls and physical pullout tests can be used to generate bias values. Bias statistics are then used to: a) improve the accuracy of underlying deterministic models used to compute nominal load and resistance values; b) remove hidden dependencies; c) select load factors; and, d) calculate resistance factors to meet an acceptable probability of failure. While the paper is focused on the pullout limit state example, the model fitting approach and LRFD calibration methodology is applicable to a wide range of other soil-structure limit state design problems in geotechnical engineering.

关键词：钢铁；极限状态；金属；附加载荷

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In the present study,the failure of basic redundant steel structural systems is investigated.By considering that each member of the system has brittle,semi-brittle,or perfectly plastic properties,the statistical behavior of perfectly brittle systems,semi-brittle systems,perfectly plastic and combination systems are evaluated,and the effects of the coefficient of variation (CoV) of members on the systems are investigated.Uncorrelated strengths with the same mean are considered for the system elements.By using the Monte Carlo simulation (MCS) method,maximum strength,yield strength and residual strength of the redundant steel structural systems are evaluated.The CoV of member strength is an essential parameter for statistical assessment of steel structural systems.In this study,the strength is defined random variable a selected normal distribution represents the random variable,for the member strength.The deformation capacity of the member is strongly depends to the characteristics of member strength,but the post failure factor has deterministic values,only for the combination system.The post failure factor is a random variable that represents the uncertainty,uniform distribution is selected to represents random variable,in combination system post failure factor.

关键词：钢铁;单调荷载;强度;变形

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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：钢铁；钢框架；增强节点；循环载荷试验

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Portable Concrete Barriers (PCBs) are used to redirect errant vehicles to keep them passing to opposing lanes and to ensure safety of the people and any objects behind the barriers. In the state of Indiana, increments to the PCBs, such as L-Shape steel plates, have been applied to enhance the safety performance of these barriers. In this study, Finite Element (FE) analyses are performed to evaluate the safety performance of PCBs with and without the increments and get thorough information about the increments applied. A full-scale crash test (INDOT, 2001) was executed for an impact to the PCBs with a 2000 kg pickup truck at an angle of 25 degrees and an initial velocity of around 100 km/hr in accordance with National Cooperative Highway Research Program (NCHRP) Report 350 guidelines for Test Level 3 safety performance. Aforementioned full-scale crash test data are used to validate the FE model constructed. Roadside Safety Verification and Validation Program (RSVVP) was used to compare the crash test and FE model results quantitatively. Validating the results of the initial FE Model leaded the way in confidence to implement the increments in the following FE Models.

关键词：钢铁；有限元法；碰撞试验；钢板

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Gravity structures play a prominent role today in North Sea oil development.These structures are not supported by piles as are most ocean structures but rather sit directly on the ocean bottom, and depend on their foundation geometries and large weights to resist severe environmental loadings.A number of structural and foundation configurations have been proposed; however,attention will be restricted in this discussion to a general configuration typical of the most prominent structures being constructed at present (1975). An example of a gravity structure is illustrated in Fig. 1. The structure foundation consists of a large caisson placed directly on the unprepared seabed surface.The deck is supported by large columns extending from the caisson.Various combinations of steel and reinforced concrete have been proposed, but the majority of structures are being constructed almost entirely of reinforced and prestressed concrete.

关键词：钢铁;重力式结构;石油;钢筋混凝土

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前5 个月，物流与生产资料市场运行基本平稳、结构优化。一方面，市场规模增速稳中小幅回落，但保持较快增长；另一方面，在增速回落的同时，市场结构向好转变、流通方式加快转型。
当前市场运行出现积极变化，PMI 指数持续回升，升幅扩大；市场需求回升，供需关系趋向改善，价格回稳；企业原材料补库趋于积极，开工率有所回升；就业形势稳中有升。预计后期经济走势趋稳。但经济回升动力仍需巩固，经济活力仍需加强。

关键词：煤炭；钢材；有色金属；天然橡胶；汽车

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以2007年中国投入产出表的数据为基础，运用投入产出模型，从投入结构、需求结构以及产业波及效果的角度定量分析了中国稀土产业与国民经济中其他产业的关联关系，给出了稀土产业的产业关联特征。从稀土产业未来发展目标的角度，对中国稀土产业的发展提出了建议。

关键词：稀土；投入产出分析；产业关联

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