Materials Science and Engineering Commons^™

Corrosion Related To The Nuclear Waste Containers, Ali Ebrahimzadeh Pilehrood

Corrosion Research

The disposal of nuclear waste is a demanding topic, and the existing methods, whether it is temporary storage in spent fuel pools or storage in geological repositories, both face the risk of corrosion-related problems. Any failure in these storage methods can potentially lead to the release of radioactive materials into the environment. To avert such catastrophic scenarios, people in the nuclear industry consistently monitor and maintain these storage facilities endlessly and attempt to improve the plans designed to store nuclear waste. Here, I will examine the nuclear waste management organization (NWMO) plan in Canada. Choosing an appropriate location for the …

Corrosion Case Study On Pipeline, Kangze Ren

Corrosion Research

The Kashagan pipeline leaks were likely caused by sulfur stress corrosion cracking, a combined corrosion mechanism developed by the presence of high pressure, the high level of hydrogen sulfide(the main "ingredient" of sour gas), and poor metallurgical choice. Improper welding and poor metallurgical examination were blamed for causing the leaking issue. The purpose of the current review is to raise the alarm about the inappropriate corrosion management of Kashagan oil production and its societal and environmental consequences.

Evolution Of Glassy Carbon Derived From Pyrolysis Of Furan Resin, Josh Kemppainen, Ivan Gallegos, Aaron Krieg, Jacob R. Gissinger, Kristopher E. Wise, Margaret Kowalik, Julia A. King, S. Gowtham, Adri Van Duin, Gregory Odegard

Michigan Tech Publications

Glassy carbon (GC) material derived from pyrolyzed furan resin was modeled by using reactive molecular dynamics (MD) simulations. The MD polymerization simulation protocols to cure the furan resin precursor material are validated via comparison of the predicted density and Young's modulus with experimental values. The MD pyrolysis simulations protocols to pyrolyze the furan resin precursor is validated by comparison of calculated density, Young's modulus, carbon content, sp carbon content, the in-plane crystallite size, out-of-plane crystallite stacking height, and interplanar crystallite spacing with experimental results from the literature for furan resin derived GC. The modeling methodology established in this work can …

Machine Learning Prediction Of Hea Properties, Nicholas J. Beaver, Nathaniel Melisso, Travis Murphy

College of Engineering Summer Undergraduate Research Program

High-entropy alloys (HEA) are a very new development in the field of metallurgical materials. They are made up of multiple principle atoms unlike traditional alloys, which contributes to their high configurational entropy. The microstructure and properties of HEAs are are not well predicted with the models developed for more common engineering alloys, and there is not enough data available on HEAs to fully represent the complex behavior of these alloys. To that end, we explore how the use of machine learning models can be used to model the complex, high dimensional behavior in the HEA composition space. Based on our …

Alca: Comparing Icelandic Aluminum Emissions To The World Through Statistical Reasoning And Programming-Based Predictive Tools, Markus Sujansky

Iceland: Climate Change and The Arctic

Aluminum production is a process that is heavily reliant on large amounts of available

energy, and therefore lends itself to locations where energy production is abundant. Iceland, as a global leader in Geothermal and Hydropower energy, has experienced an industrial boom in the past 20-30 years, quickly becoming a top 10 worldwide aluminum producer. However, although the three main companies that operate their smelting processes in the country are powered by clean energy, they still import raw materials from all over the world, with source locations ranging from Brazil to Australia. In order to find out if the long distance …

Asymmetric Electrode-Electrolyte Interfaces For High-Performance Rechargeable Lithium-Sulfur Batteries, Jia Chou, Ya-Hui Wang, Wen-Peng Wang, Sen Xin, Yu-Guo Guo

Journal of Electrochemistry

With a high cell-level specific energy and a low cost, lithium-sulfur (Li-S) battery has been intensively studied as one of the most promising candidates for competing the next-generation energy storage campaign. Currently, the practical use of Li-S battery is hindered by the rapidly declined storage performance during battery operation, as caused by irreversible loss of electroactive sulfide species at the cathode, dendrite formation at the anode and parasitic reactions at the electrode-electrolyte interface due to unfavorable cathode-anode crosstalk. In this perspective, we propose to stabilize the Li-S electrochemistry, and improve the storage performance of battery by designing asymmetric electrode-electrolyte interfaces …

Hydrophobicity Optimization Of Cathode Catalyst Layer For Proton Exchange Membrane Fuel Cell, Hao-Jie Chen, Mei-Hua Tang, Sheng-Li Chen

Journal of Electrochemistry

Hydrophobicity of the cathode catalyst layers (CCLs) crucially determines the performance of proton exchange membrane fuel cells (PEMFCs) by affecting the transports of oxygen and liquid water. In this regard, polytetrafluoroethylene (PTFE) is usually used as a hydrophobic additive to facilitate the oxygen and water transports in CCLs. So far, there remains lacking systematic effort to optimize the addition methods of PTFE in CCLs and the mechanisms behind. In this work, the effects of the approaches for PTFE addition and the distribution of PTFE on the mass transport of oxygen and the proton conduction in CCLs were studied by using …

Dependence Of Heat Transfer Model On The Structure Of Electrically Coil-Heated Microelectrodes, Ju Li, Sen Yang, Jian-Jun Sun

Journal of Electrochemistry

Electrically heated microelectrodes have gained much attention in electroanalytical chemistry in recent years. It has been shown that the promotion of mass transport and reaction kinetics at high-temperatures often results in increased current signals. However, there is no study about the heat transfer inner the microelectrodes which is necessary for the design and operation for microsensors. This report introduces a finite element software (COMSOL) to analyze the factors that influence the surface temperature (T_s), which is crucial for the heating ability of micro-disk electrodes with coils. Distances between the electrode surface and the bottom of the heated copper …

Synergistic Effect Of Nanoclay And Barium Sulfate Fillers On The Corrosion Resistance Of Polyester Powder Coatings, Jinbao Huang, Marshall Shuai Yang, Chengqian Xian, James Joseph Noel, Yolanda S. Hedberg, Jian Chen, Ubong Eduok, Ivan Barker, Jeffrey Daniel Henderson, Haiping Zhang, Liqin Wang, Hui Zhang, Jesse Zhu

Chemistry Publications

No abstract provided.

Summarization Of Reliability Theory For Condition Assessment Of Brige Structurs, Peng Jianxin, Chai Ying, Zhang Jianren

Journal of China & Foreign Highway

This paper briefly reviewed the principles and development of structural design theories, and summarized the current research of structural reliability theories. Meanwhile, various applicable methods of reliability theories were finely described and analyzed, with the latest progress in structural reliability analysis and reliability-based design optimization outlined. Additionally, the uncertainty propagation methods and reliability assessment methods were analyzed, and the development trend of structural reliability was summarized, which can provide a summary and reference for future researchers to study structural reliability.

Study On Laws Of Surface Movement A Nd Deformation Of Goaf Under Subgrade In Sand-Loess Area, Lei Mingxuan, Liu Guotian, Su Weiwei, Zhang Liujun, Yin Lihua

Journal of China & Foreign Highway

A large number of goaf under sand-loess areas in China greatly restrict the highway construction development in sand-loess areas. Meanwhile, the goaf evaluation beneath under subgrade in sand-loess areas is especially important. According to the characteristics of goaf beneath the highway of sand-loess areas, based on FLAC3D software, this paper selected reasonable parameters to build the model of goaf under subgrade. Additionally, based on the mechanical property analysis of sand loess, the laws of surface movement and deformation parameters of the goaf under the subgrade were summarized, and the surface movement and deformation areas were identified, with the range of …

Exploring Long-Term Protective Effect Of High Vertical Sand Barrier On Top Of Complex Longitudinal Sand Ridge In Taklamakan Desert, Jin Changning

Journal of China & Foreign Highway

By taking the high vertical sand barriers deployed on the top of the complex longitudinal sand ridges in the hinterland of Taklamakan Desert as the object, this paper investigated the sand protection effect from the long-term perspective on the basis of several years’ comparative observation. The result analysis shows that in addition to the recognized sand blocking effect, high vertical sand barriers also have a more important role of sand fixation, which means that the barriers can change the original overall movement of sand dunes into only the falling sand slope forward, with the windward slopes basically fixed. Even if …

Experimental Study On Dynamic Resilient Modulus Of Cement-Improved Fine-Grained Soils In Wet Subgrade, Huang Chongwei, Zhu Baobing, Zhang Yi, Sun Yu, Guo Dandan

Journal of China & Foreign Highway

To investigate the design and construction of wet subgrade in southern China, this paper selected three typical soil samples of the new highway subgrade of Ecological Avenue in Chongming District, Shanghai, and improved the samples by cement disposal technology. Meanwhile, the effects of the water content, degree of compaction, cement content, age of maintenance and stress state on the dynamic resilient modulus were analyzed by experimental methods. The results show that the effects of cement content, water content and age of maintenance on the dynamic resilient modulus of three kinds of cement-improved fine-grained soil in wet subgrade are larger, and …

Study On Stability Analysis And Treatment Of A Expressway Landslide, Huang Hongchao

Journal of China & Foreign Highway

In highway construction of mountainous areas, landslides are easily triggered due to the complex geological conditions, thereby causing serious economic loss and even casualties. Therefore, the study of landslide treatment schemes has caught increasingly more attention from scholars. By taking the giant landslide treatment on a highway of southeastern Yunnan as an example, this paper analyzed the process and cause of giant landslide formation, and then conducted inverse calculations to determine the stability analysis parameters of landslides via combining the topography and geology and slope state before and after slope excavation. Finally, according to the calculation results of the residual …

Discussion On Treatment Scheme Of Soft Foundation Based On Cooperative Deformation Of Roadbed And Frame Structure, Liu Jizhong, Chen Kai, Yang Fengyu

Journal of China & Foreign Highway

In view of insufficient consideration of cooperative roadbed and structure deformation, by taking the soft foundation with frame structures in the fill roadbed as the research object, this paper adopted Midas GTS NX finite element analysis software to simulate the pavement settlement and plastic zone distribution of the soft foundation treated by cast-in-place piles. Considering that the stiffness difference between the roadbed and the frame structure can easily result in pavement cracking, a variable stiffness composite foundation treatment optimization scheme was proposed. This scheme coordinated the cooperative settlement and deformation of the roadbed and frame structure, and prevented the development …

Study On Key Technology Of Landslide Investigation And Treatment Plan Of Coal Stratum In Section K 132 Of A Highway, Wei Dongxu, Wang Guanguo, Li Jian, Zheng Guosheng

Journal of China & Foreign Highway

Coal strata feature soft lithology, low strength and easy softening under contact with water. During the subgrade excavation, the slopes of the coal strata often form a potential slip surface, which can control the stability of the overall slope. By taking the K132 landslide of Longchuan-Huaiji Expressway as an example, this paper comprehensively determined the characteristics of the landslide in coal strata, especially the characteristics of slip surfaces, by adopting the high-density resistivity and deep-hole displacement monitoring methods and combining geological drilling. The stability analysis results show that the carry-over factor method and Geoslope analysis can calculate the residual sliding …

Feasibility Study Of Pavement Rutting Evaluation Method Based On Driving Vibration, Zhang Jinxi, Wang Peirong, Cao Dandan, Ceng Jingxiang

Journal of China & Foreign Highway

To explore the intelligent detection and monitoring methods of pavement performance, this paper utilized the self-developed driving data collection app to collect vibration acceleration and other data of the pavement during driving, and carried out the feasibility study of evaluating the pavement rutting by driving vibration. Firstly, the collected vibration acceleration data was processed for noise reduction, and the driving vibration characteristics in different working conditions were analyzed. Secondly, seven time domain indicators with high correlation between vibration acceleration and the rutting were extracted as the initial set of indicators, and the seven indicators were downscaled into two independent principal …

Study On Influence Factors Of Temperature Field Of Crc+Ac Composite Road Surface, Cheng Xiaoliang, Zhang Hao, Li Sheng

Journal of China & Foreign Highway

In view of the factors influencing the temperature field of CRC+AC composite road surfaces, this paper analyzed the temperature field distribution and influencing factors of CRC+AC composite road surface structures based on the meteorology and heat transfer theories, and conducted 3D solid modeling and numerical simulation by adopting Abaqus finite element software. The results show that in certain conditions, the deeper distance from the road surface leads to smaller temperature change of the road surface structure. When the depth exceeds 0.6 m, the temperature is almost unchanged and has little difference with the outside ambient temperature. By increasing the thermal …

Design Of Polymer Optical Fiber Icing Sensor And Detection Method Of Road Ice Thickness, Xie Qingzhong, Wang Ling, Ge Jingyong, Shi Ning, Zhang Jiupeng

Journal of China & Foreign Highway

To detect the icing condition and icing thickness of asphalt pavement in extreme weather conditions, this paper firstly compared the performance indexes of polymer optical fiber and quartz optical fiber, chose polymer optical fiber as the optical transmission medium, and selected the distribution mode of coaxial sensor probes. Meanwhile, it designed the weak signal detection circuit and finally completed the design of a polymer optical fiber road icing sensor. Secondly, it was verified that the effect of temperature on the icing detection results was negligible, and icing tests under different light intensities were conducted under simulated light, with the icing …

Study On Theoretical Relationship Between Acceleration Of Vehicle Suspension And International Roughness Index, Lv Wenjiang, Zhang Zhen

Journal of China & Foreign Highway

The international roughness index (IIRI) has become one of the most widely employed indexes to characterize the surface roughness. However, there are still some problems in the current research on the calculation of this index by adopting vertical acceleration data of vehicles. For example, the influence of vehicle suspension parameters on the test results is not sufficiently taken into account, and the applicability of regression analysis equations between vehicle acceleration and this index is low. This paper studied a method of determining this road surface roughness index with the suspension parameters of the test vehicle considered. The actual road tests …

Study On Influence Of Different Subgrade Types On Low Temperature Shrinkage Performance Of Asphalt Pavement, Xu Yongli, Guo Yang, Sun Zhiqi

Journal of China & Foreign Highway

To study the influence of different subgrade types on the low-temperature shrinkage performance of asphalt pavement, this paper designed two kinds of asphalt pavement combination structures for the semi-rigid subgrade and flexible subgrade: AC-16+cement-stabilized gravel and AC-16+asphalt-stabilized gravel. Strain gauges were attached at the center of the sides of the two materials and at the characteristic positions of the interfaces between the layers, and the resistance strain gauge measurement method was employed to carry out the temperature shrinkage test of the combined structure and thus obtain the strain changes at each position during the cooling process, with the influence of …

Research On Effect Of Structural System On Static And Dyn Amic Stiffness Of Large-Span And Narrow Suspension Bridges, Song Songke, He Jiayong, Chen Qian, Du Taoming, Li Yongle, Yu Chuanjin

Journal of China & Foreign Highway

Large-span and narrow suspension bridges featuring flexible structures and low overall stiffness have prominent wind resistance problems. Structural static and dynamic stiffness is the basic parameter for wind resistance of long-span bridges. By taking a large-span and narrow suspension bridge as the research project, this paper comparatively analyzed the effects of parameters such as stiffened girder stiffness, main cable span ratio, main cable spacing, and lifting point width on the static and dynamic stiffness based on the theory of spatial cable segmental suspension lines and three-dimensional finite element models of bridges under multi-working condition systems. The results show that the …

Research On Design Method Of Anti-Overturning Stability Of Large Cantilever Steel Truss Beam Traverse Construction Based On Reliability Inversion Theory, Yang Shusheng, Cui Fengkun, Wang Jiansheng, Su Baozhong, Xu Shaoxia

Journal of China & Foreign Highway

To evaluate the safety of large cantilever steel truss beams in traverse construction, this paper proposed a method of evaluating the safety factor of anti-overturning stability of large cantilever steel truss beams based on the reliability inversion theory. Under the premise of giving the target reliability index and considering the randomness of the structural parameters, this method adopted the reliability inversion theory to solve the anti-overturning safety factor of large cantilever steel truss beams in traverse construction. Finally, the method was utilized to study the anti-overturning stability of the 82 m large cantilever steel truss beam of Weilai High-speed Railway …

Experimental And Simulation Study On Bond Degradation Of Fractured Prestressed Tendons, Yong Pan, Li Cong, Chen Guan, Xiang Dan, Hu Xianwei, Qi Honghe

Journal of China & Foreign Highway

To solve the corrosion and fracture of prestressed tendons in the end-anchor area of post-tensioned prestressed concrete (PC) girders under the chlorine salt environment, this paper employed electrochemically accelerated corrosion tests to obtain three PC members after the fracturing of prestressed tendons in the end-anchor area, and then carried out the static drawing test to study the effects of concrete strength and stirrup diameter on the bonding performance of prestressed tendons after fracturing. The results show that the bond damage of the strands starts at the drawing end and gradually develops to the free end. Additionally, increasing the concrete strength …

Parameters Study On Durability Of Substation Structure Of Multi-Tower Suspension Bridge, Qin Xiao, Pan Ji, Xiao Rucheng

Journal of China & Foreign Highway

Substation structures are important components of the bridge structure, and their durability will affect the service life of the overall bridge structure. Since the overall structure of a multi-tower suspension bridge is more flexible with larger deformation, and the cumulative displacement at the substation structure is also larger, the durability problem of the substation structure is more prominent under multi-tower suspension bridges. To qualitatively analyze the influence of the structural parameters of the bridge structure (including tower-beam connection and cable-beam connection methods) on the durability of the substation structure, this paper built a finite element model of a four-tower suspension …

Influence Of Shear Deformation On Manufacturing And Erection Alignment, Wang Jin, Chen Changsong

Journal of China & Foreign Highway

This paper aims to study the effect of shear deformation on the manufacturing and erection alignment of main girders of free cantilever erection steel box girder bridges and better design the state of bridge formation state. To this end, it calculated the shear stress coefficient of uniformity of the steel box girder’s cross-section by adopting the finite element method and conducted comparison with the solid model of the plate and shell units of the steel box girder. The results show that the shear stress coefficient of uniformity calculated by finite element software is accurate and reliable. Additionally, simple modeling indicates …

Study On Temperature Gradient Of Long-Span Single-Box Double-Chamber Box Girder Bridge, Yang Wenbin

Journal of China & Foreign Highway

In view of the complex temperature effect of the single-box double-chamber box girders, this paper aimed to carry out the temperature gradient study of box girder cross-sections by employing a short-tower single-box double-chamber cable-stayed bridge with span arrangement of (120+120) m. 21 temperature sensors were installed at the cross-sections of large-mileage closure sections, with the set collection frequency of one time per hour and a wireless collection module for data collection. Meanwhile, temperature observation was carried out for a period of 171 d to obtain the distribution law of the temperature gradient in cross-sections of the closure sections. The study …

Study And Implementation Of Jacking Scheme Of Vertical Curve Beam With Two -Way Longitudinal Slope Without Adjusting Temporary Pier Top Elevation, Zhang Hongwu, Ke Hongjun, Chen Zhuoyi, Yang Wu

Journal of China & Foreign Highway

The bridge alignment design is the straight line+circular curve+straight two-way longitudinal slope vertical curve variable curvature steel bridge jacking. To deal with this problem, this paper analyzed the shortcomings of existing schemes such as real-time or multiple adjustments to the temporary pier top elevation, and proposed a jacking scheme of taking full advantage of the steel bridge’s characteristics including small flexural rigidity, strong adaptive deformation ability and high material strength, without adjusting the temporary pier top elevation. Additionally, the whole-process finite element simulation analysis was conducted on this scheme via a background project, with the calculation results revealing safety and …

Optimization Of Bridge Life Cycle Maintenance Decision Based On Lca And Lcc, Liu Shuguang, Liu Jun, Liu Yonghua, Wang Fan

Journal of China & Foreign Highway

To study the optimal maintenance strategy for bridges over the whole life cycle under the influence of life cycle environment and life cycle cost, this paper built a multi-objective optimization model for bridge life cycle maintenance decision by adopting preventive maintenance and substantial maintenance as the basic maintenance methods, and bridge reliability, life cycle environment and life cycle cost as the objective functions. Additionally, it derived the quantification method of indicators including the time-varying reliability, life cycle environment and life cycle cost indicators of the bridge, and determined the computational process of bridge life cycle maintenance decision optimization based on …

Experimental Study On The Influence Of Cantilevered Sidewalk On The Wind Resistance Of A Cable-Stayed Bridge With Pk Girder, Yu Zhenghua

Journal of China & Foreign Highway

Bilateral box steel main girders are widely employed in large-span double-plane cable-stayed bridges. These bridges are characterized by low frequency, small damping, and relatively light mass, and their wind resistance stability is a key problem to be solved in bridge construction. By taking the Pingnan super major cable-stayed bridge with a main span of 636 m on Pingrong Expressway under construction as the research project, this paper built a finite element spatial model of the bridge and analyzed the structural modal characteristics. Meanwhile, it carried out the main girder segmental model of elastically suspended vortex vibration and chatter vibration wind …