Erosion behavior of the high velocity oxy fuel (HVOF) deposited Cr_3C_2-NiCr and WC-Co coatings on boiler tube steels was evaluated. The solid particle erosion study was conducted, using an air jet erosion test rig at a velocity of 26 m/s and impingement angles of 30° and 90°, on uncoated as well as HVOF spray coated boiler tube steels at 250 ℃. The coatings are significantly harder than the substrate steel and less porous. Scanning electron microscopy (SEM) technique was used to analyze the eroded surface. Mass loss of the coatings was found higher than the boiler tube steel.

关键词：钢铁;超音速火焰喷涂;侵蚀;扫描电子显微镜

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The thermal performance Rov of Flat-Plate Closed-Loop Pulsating Heat Pipe(FCLPHP) are effected by several elements such as the heat load Q, the tilt angle θ and the filling ratio F, they are interacted each other.In order to predict the effect of Q and θ on the thermal performance at locations Q and θ other than the experimental data conditions, and to study the relationship among the Rov, Q and θ in the range of the experimental data, we need a fitted regression model to estimate the function relationship that describes the data.The postulated depends on the range of the regression variables encountered in the data.In this paper, a simple model was developed.Since the coefficients in the model have been estimated from the experimental data, studies were carried out on an experimental set-up.FC72 was employed as working fluid.Method of least squares was used for building the model.By using the model, effects of the beat load and the tilt angle on the thermal performance of FCLPHP were discussed.It was found that the tilt angle had minimum value in a certain heat load in the experimental range (θ=30°-70°), and it increases with the increase of heat load.A sensitivity analysis was done with the model.

关键词：钢铁；脉动热管；热性能；整体热阻

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This research investigates the behavior of a geosynthetic reinforced sandy soil foundation using laboratory model footing tests. The model footings were steel plates with dimensions of 152 mm × 152 mm. The parameters investigated in this study included top layer spacing, number of reinforcement layers, vertical spacing between layers, tensile modulus and type of reinforcement, and embedment depth. The test results showed that the inclusion of reinforcement can appreciably improve the soil's bearing capacity. Higher tensile modulus geosynthetics performed better than others; and that sand reinforced by the composite of geogrid and geotextile performed better than those reinforced by geogrid or geotextile alone. The test results also showed that the reinforcement configuration/layout has a very significant effect on the bearing capacity of reinforced foundation. The results of the model footing tests were compared with the analytical solution developed by the authors in a previous study. The analytical solution gave a good predication of the experimental results of footing on geosynthetic reinforced sand.

关键词：加固砂土地基；合成材料；钢筋

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For this study, a novel optical fiber sensing system was developed and tested for the monitoring of corrosion in transportation systems. The optical fiber sensing system consists of a reference long period fiber gratings (LPFG) sensor for corrosive environmental monitoring and a LPFG sensor coated with a thin film of nano iron and silica particles for steel corrosion monitoring. The environmental effects (such as pH and temperature) are compensated by the use of the reference LPFG sensor. The sensor design, simulation, and experimental validation were performed in this study to investigate the feasibility of the proposed sensing system for corrosion and environment monitoring. The detailed investigations of the proposed sensing system showed that within the detection limitation of the thin coated layer, the proposed sensor could monitor both the initial and stable corrosion rate consistently. Compared to the traditional electrochemical method, the proposed optical fiber sensing system has a converter coefficient of 1 nm/day=3.746(10-3 A/cm2). Therefore, the proposed nano iron/silica particles dispersed polyurethane coated optical fiber sensor can monitor the critical corrosion information of the host members in real time and remotely. With multiple LPFGs in a single fiber, it is possible to provide a cost-effective, distributed monitoring solution for corrosion monitoring of large scale transportation structures.

关键词：光纤;交通系统;环境影响

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The bridge is a basic element of all surface transportation networks. In military theaters of operation, transportation routes that cross bridges are essential for deploying personnel, supplies, and heavy equipment, as well as for facilitating communications. It is essential that the structural capacity of each bridge along a military route be assessed in order to avoid overloading the bridge or unnecessarily hindering military operations by overestimating or underestimating its capacity. For reinforced concrete structures, information about the number, size, and orientation of steel reinforcement is necessary to make a strength assessment. Since reinforcement is not visible externally, making an accurate assessment without design drawings is extremely difficult. The objective of this project was to develop more reliable means of in-field capacity assessment of reinforced concrete bridges by making improved estimates of the level of longitudinal and shear reinforcement. The proposed assessment procedure is based on comparing measured structural response under controlled loading conditions to predicted structural response from analysis. This report presents results from a preliminary sensitivity study of the analytically predicted response of simply supported reinforced concrete T-beam girders that have varying levels of longitudinal and shear reinforcement.

关键词：钢铁；桥梁；结构完整性；容量（数量）；探测器;

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In support of Hanford's feed delivery of high level waste (HLW) to the Waste Treatment and Immobilization Plant (WTP), pilot-scale testing and demonstrations with simulants containing cohesive particles were performed as a joint collaboration between Savannah River National Laboratory (SRNL) and the Pacific Northwest National Laboratory (PNNL) staff. The objective of the demonstrations was to determine the impact that cohesive particle interactions in the simulants, and the resulting non-Newtonian rheology, have on tank mixing and batch transfer of large and dense seed particles. The work addressed the impacts cohesive simulants have on mixing and batch transfer performance in a pilot-scale system. Kaolin slurries with a range of wt percent concentrations to vary the Bingham yield stress were used in all the non-Newtonian simulants. To study the effects of just increasing the liquid viscosity (no yield stress) on mixing and batch transfers, a glycerol/water mixture was used. Stainless steel 100 micron particles were used as seed particles due to their density and their contrasting color to the kaolin and glycerol.

关键词：放射性废物管理；水泥浆；不锈钢

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With the advancement of many off-the-shelf data acquisition systems readily available today and the availability of 3G and 4G highspeed wireless cellular networks, the potential for remote monitoring of critical bridges has never been better. Needs exist regarding scour and general structural response for long-term monitoring. However, short-term monitoring using quickly deployable, rugged systems are also desirable in cases where impact, fire, environmental effects, or other damage may occur. These robust systems can be deployed rapidly, and endure harsh elements, enabling DOTs to constantly assess and monitor a structure, or a network of structures. Hence, the objective of this project is to explore the feasibility and proof of concept of using a web-based bridge monitoring interface for use on selected INDOT bridges for both short-term and long-term applications. This report will focus on a single case study, the Virginia Ave Bridge over I-65 SB, a steel plate girder bridge that frequently falls victim to truck impact as a result of low clearance. This case study is uniquely different and provides insight into how targeted instrumentation systems can be used to probe specific parameters desired by owners for bridge condition assessment and monitoring. It will be shown how commercially available instrumentation systems can be tailored to fit any unique application required. Additionally, it will be demonstrated that INDOT benefited from this specific case of fielddeployed, short-term monitoring, which included automated notifications of critical onsite conditions.

关键词：钢铁;结构分析;土木工程;桥梁

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Based on the reversed cyclic loading test of three 1∶4 high-strength concrete flat columns,the computer program ABAQUS was used to simulate behaviors of the specimens.Concrete in the column was modeled using the damage plasticity material model,and a uniaxial steel model with combined isotropic and kinematic hardening properties was used to simulate the behavior of the reinforcement.The establishment of the finite element model,definition of the material parameters and the influence of diagonal reinforcement were discussed at length.The results show that the concrete damage plasticity model can be well used for hysteretic analysis of reinforced concrete members if the relevant parameters are reasonably defined.Diagonal reinforcements can not significantly improve ductility of the specimens,but can improve their shear capacities.This paper can provide reference for the performance simulation of reinforced concrete members under cyclic loading.

关键词：对角加固;高强混凝土;平柱;循环荷载

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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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Calabazas Creek Research, Inc. developed a load capable of continuously dissipating 2 MW of RF power from gyrotrons. The input uses HE11 corrugated waveguide and a rotating launcher to uniformly disperse the power over the lossy surfaces in the load. This builds on experience with a previous load designed to dissipate 1 MW of continuous RF power. The 2 MW load uses more advanced RF dispersion to double the capability in the same size device as the 1 MW load. The new load reduces reflected power from the load to significantly less than 1. This eliminates requirements for a preload to capture reflected power. The program updated control electronics that provides all required interlocks for operation and measurement of peak and average power. The program developed two version of the load. The initial version used primarily anodized aluminum to reduce weight and cost. The second version used copper and stainless steel to meet specifications for the ITER reactor currently under construction in France. Tests of the new load at the Japanese Atomic Energy Agency confirmed operation of the load to a power level of 1 MW, which is the highest power currently available for testing the load.

关键词：钢铁；ECR加热；铝；铜；峰值负载

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