A new chloroacetic-acid modified imidazoline (CAMI) was synthesized via the quaternization of imidazoline intermediate,obtained from the amidation and cyclization reactions of benzoic acid and diethylene triamine,with chloroacetic-acid.The performance of the synthesized compound CAMI as corrosion inhibitor for Q235 carbon steel in 5％ sulfuric acid solution was investigated by weight loss measurement and potentiodynamic polarization technique.The results show that CAMI possesses strong inhibitive effect on the corrosion of Q235 carbon steel in acid medium and restrains the corrosion without changing the cathodic and anodic corrosion mechanism as a mixed-type inhibitor.

关键词：季铵化咪唑啉；缓蚀剂；失重法；极化曲线

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Structural Health Monitoring has great potential to provide valuable information about the actual structural condition and can help optimize the management activities. However, few effective and robust monitoring methods exist which hinders a nationwide use of SHM in structural condition evaluations. The objective of this project was to research and develop methods for structural identification and damage detection based on strain monitoring using long-gauge fiber-optic sensors. In particular two universal parameters of beam-like structures were studied in detail: the neutral axis and deformed shape. Data from two structures were used for validation purposes: from on-site monitoring of the US202/NJ23 overpass and from lab testing of a scale-model of a similar structure. The conclusions are that while the neutral axis varies during dynamic events, it changes the location due to damage, and it can be located accurately using a probabilistic approach. Thus, it can be used as a damage sensitive feature. At least two sensors per cross-section are necessary for an accurate evaluation of the location of the neutral axis. The vertical displacement of beams can be calculated by double integration of the curvature. However, the double integration method affects the accuracy of the evaluation, and to achieve the most accurate result a linear combination of integration methods is recommended. At least three locations along each girder should be instrumented with two parallel sensors for accurate evaluation of the vertical displacement. The methodologies researched in this project are presented in this report and recommendations for the use of the methods provided.

关键词：复合材料；纤维光学；钢筋混凝土；钢铁

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A new project to analyse neutrino features is under development within the frame of the High Intensity Neutrino Oscillation EURONu project [1]. The final shape of the magnetic horns supporting system is proposed. This system is designed for four horns joined in one assembly. For the support structure a search for the optimal parameters is made with respect to the static loads. After that dynamic analysis is performed, this is used, if necessary, for the final tuning of the designing parameters. The above approach is investigated for two different materials used for the support system.

关键词：磁喇叭；中微子振荡颗粒；支持系统

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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：极限状态；阻力系数；钢铁

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Accurate estimates of bearing stiffnesses are often necessary for bridge design and construction calculations. In the case of steel-reinforced elastomeric bearing pads, the compression stiffness or roll stiffness is sometimes difficult to estimate because of complex deformations of the elastomer. A method of numerical analysis for estimating the axial and roll stiffnesses of bearing pads is presented. To validate the axial calculation method, experimental compression tests were performed on pad specimens constructed in accordance with Florida design standards. A method for calculating roll stiffness is also presented in which the pad is modeled as a grillage of compression-only axial springs. The grillage method was partially derived from roll stiffness data measured in a separate experimental study. The grillage method was demonstrated to accurately capture both the nonlinear moment-rotation behavior caused by liftoff of the girder from the pad and the observed sensitivity of roll stiffness to initial compressive loading caused by self-weight of the girder. Reductions in roll stiffness that are caused by girder slope relative to the pad were also examined.

关键词：轴承刚度；精确估计；钢铁

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Retaining wall using steel frame and fill material is a kind of the cellular structure. The cellular structure using a fill material has a number of advantages such as excellent constructability in the short term, permeability, and decrease in effects of groundwater fluctuations after the end of construction. Because this structure is discontinuity, it is quite difficult to apply analysis in finite element methods. In addition, there are no evaluation techniques to establish its shear resistance clearly. In order to solve the issue, this paper presents that shear resistance analysis is performed by introducing displacement incremental analysis into the distinct element method. It enables not only to model continuous and discontinuous structure, but also to perform static and dynamic analysis. The results of analysis are compared with experimental results of the retaining wall with a steel frame and fill materials.

关键词：细胞结构；剪切阻力；填充材料；离散元法

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Improved software interoperability is key to realizing more fully the potential benefits of integrated and accelerated project delivery in a way that also somehow ensures product quality. The increasing appeal of three-dimensional (3-D) building information modeling (BIM) notions applied to bridges [known as bridge information modeling (BrIM)] motivates the need for principled prescriptions of associated electronic data exchanges between various project stakeholders and the various software applications that they use. Such data exchanges must be sufficiently precise to facilitate detailing for fabrication and construction while being sufficiently concise to facilitate parametric modeling and thereby avoid needless data duplication. The highway geometry to which bridges must conform distinguishes BrIM from the building column grid orientation of BIM at the outset of the bridge life cycle. In contrast to the overdefined highway geometry in the LandXML data exchange standard, a 3-D control curve is defined, presented, illustrated, and recommended as the basis for parametric data exchange suitable through the life cycle of steel Ⅰ-girder bridges on (straight and) curved alignments. This 3-D control curve combines in a single curve the traditional horizontal control line and profile grade line that bridge structural engineers receive from highway designers to define bridge geometry. Data exchanges associated with three distinct stages in the life cycle of a steel bridge are defined and illustrated: analysis and design, detailing for fabrication, and erection and construction. The data exchange based on a 3-D control curve provides the data integrity required through the life cycle of a steel bridge.

关键词：三维参数；钢铁；曲线钢桥

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This paper presents a comparison of test results on the material behavior of zero-slump, dry-cast steel and synthetic fiber-reinforced concrete. ASTM C1609 flexural beam test and ASTM C39 compressive strength cylinder tests were conducted for various fiber dosages of each type of synthetic and steel fiber. Synthetic and steel fiber dosages ranged from 4 lb/yd~3 to 18 lb/yd~3 and 22 lb/yd~3 to 88 lb/yd~3, respectively. From these tests, material properties were found that included compressive strength, first-peak load, peak load, modulus of rupture, and specimen toughness. These values were all within the range of conventional design parameters used in concrete structures. ASTM beam load-deformation plots were obtained for each fiber beam to show the fiber behavior and strengthening after the initial crack.

关键词：钢铁；合成纤维材料；混凝土材料

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Although steel orthotropic deck is currently the most widely adopted solution for long-span bridges, the poor adhesion to the upper asphalt layers still represents a serious problem without a clear solution. In recent decades many techniques that involve the use of special bituminous bonding coats, reinforced asphalt membranes, net-reinforced steel deck surfaces, or epoxy asphalt binders have been applied, with varying results, to improve the level of adhesion of the asphalt pavement to the steel surface. In this experimental study, two such techniques were adopted to investigate the shear resistance of steel-asphalt pavement systems. The first technique used epoxy asphalt both as a bonding coat and as a binder of the upper asphalt layer, while the second technique involved the use of a reinforced asphalt membrane that was applied on the steel deck before overlaying with conventional hot-mix asphalt (HMA). The Ancona Shear Testing Research and Analysis shear test device was used to evaluate the shear resistance of different types of HMA-steel interfaces and to investigate the effects of temperature and normal stress. The results have been compared with the shear properties of bitumen-coated interfaces, studied in previous research. The results showed that epoxy asphalt guaranteed high performance regardless of the test temperature. However, the shear resistance of the system with the asphalt membrane was lower than with the epoxy asphalt, although it was higher than the resistance of bitumen-coated interfaces at high temperatures.

关键词：正交异性钢桥；钢铁；沥青膜

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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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