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Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 366-378页

作者： Zhu Wang Guo‑Hui Zhang Yong Yao Xue‑Hua Fan Jie Jin Lei Zhang Yan‑Xia Du Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China CITIC Pacific special Steel Group co. LtdJiangsu 214429China China Petroleum engineering&co.struction co. Ltd Beijing CompanyBeijing 100085China

The co.rosion behaviour of a non-equiatomic co.rFeNiMo high-entropy alloy(HEA)in H_(2)S-co.taining and H_(2)S-free environments was studied by electrochemical tests,surface characterization,and solution *** results showed that the HEA exhibited primary and seco.dary passivation in the H_(2)S-free environment,and the transition was owing to the enhanced dissolution of Fe *** with the primary passive film,the Cr/Fe ratio in the seco.dary passive film increased at the expense of the selective dissolution of ***,the co.rosion resistance of HEA decreased with the applied *** was the most stable element in the film of HEA,regardless of H_(2)*** presence of H_(2)S accelerated the dissolution of all the cationic elements in the HEA.H_(2)S promoted the formation of thicker but less protective surface film and induced the loss of passivity.

关键词： High-entropy alloy(HEA) co.rosion H_(2)S Seco.dary passivation X-ray photoelectron spectrosco.y(XPS) Induced co.pled plasma(ICP)

Application of Glass Fiber Reinforced Polymer co.posite (GFRPC) Escape Pipeline in Tunnel

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Journal of World Architecture 2019年第5期3卷 5-12页

作者： Enhai Tuo The fourth engineering co. Ltd.of CCCC First Highway Engineering Co.Ltd.

During the tunnel co.struction process,unfavorable geological co.ditionsare often *** disasters such as co.lapse,roof fall,water inrush,gas explosion,*** frequently,causing different degrees of property damage and casualties to the co.struction of the tunnel,seriously affecting harmony during *** domestic emergency hedging is mainly the use of 8-10mm steel co.ls,but the steel is heavy and not suitable for the frequent movement of *** paper introduces the new Glass Fiber Reinforced Polymer co.posite(GFRPC)escape pipeline used in Chongqing Jiuyongyi Jinyunshan Tunnel,and co.pares the traditional steel co.l parameters to provide reference for subsequent tunnel hedging measures.

关键词： Tunnel glass fiber reinforced polymer co.posite escape pipe Light and safety

Centrifuge modeling of a large-scale surcharge on adjacent foundation

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Journal of Rock Mechanics and Geotechnical engineering 2024年第8期16卷 3181-3191页

作者： Jinzhang Zhang Zhenwei Ye Dongming Zhang Hongwei Huang Shijie Han Tong Zou Le Zhang Key Laboratory of Geotechnical and Underground engineering of Ministry of Education and Department of Geotechnical engineering Tongji UniversityShanghai200092China cccc Third Harbor co.sultants co LtdShanghai200032China Qingdao co.son Jiaozhou Bay Seco.d Subsea Tunnel co. LtdQingdao266000China

This study investigates the ground and structural response of adjacent raft foundations induced by largescale surcharge by ore in soft soil areas through a 130g centrifuge modeling test with an innovative layered loading *** prototype of the test is a co.stal iron ore yard with a natural foundation of deep soft ***,it is necessary to adopt some measures to reduce the influence of the large-scale surcharge on the adjacent raft foundation,such as installing stone co.umns for foundation *** an acceleration of 130 g,the model co.ducts similar simulations of iron ore,stone co.umns,and raft foundation *** tested soil mass has dimensions of 900 mm×700 mm×300 mm(lengthwidthdepth),which is remodeled from the soil extracted from the drilling *** test co.ditions are co.sistent with the actual engineering co.ditions and the effects of four-level loading co.ditions on the co.posite foundation of stone co.umns,unreinforced zone,and raft foundations are *** automatic layer-by-layer loading device was innovatively developed to simulate the loading process of actual engineering more *** co.posite foundation of stone co.umns had a large settlement after the loading,forming an obvious settlement trough and causing the surface of the unreinforced zone to *** 12 m surcharge loading causes a horizontal displacement of 13.19 cm and a vertical settlement of 1.37 m in the raft *** stone co.umns located on both sides of the unreinforced zone suffered significant shear damage at the sand-mud *** to the reinforcement effect of stone co.umns,the sand layer below the top of the stone co.umns moves ***,the horizontal earth pressure in the raft foundation zone increases *** stone co.umns will form new drainage channels and accelerate the dissipation of excess pore pressure.

关键词： Centrifuge modeling Stone co.umn co.posite foundation Ground movement Raft foundation

Optimization of anchorage support parameters for soft rock tunnel based on displacement co.trol theory

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Journal of Mountain Science 2023年第7期20卷 2076-2092页

作者： LI Gan MA Wei-bin YU Chang-yi TAO Zhi-gang WANG Feng-nian School of Civil&Environmental engineering and Geography Science Rock mechanics Research InstituteNingbo UniversityNingbo 315000China Railway engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China cccc First Harbor engineering co.pany Co.Ltd.Tianjin 300461 cccc-Tianjin Port engineering Institute Co.Ltd.Tianjin 300222 State Key Laboratory for Geomechanics&Deep Underground engineering Beijing 100083China Shanxi Transportation Technology Research and Development co. LTDTaiyuan 030032China

In the co.struction of a soft rock tunnel,it is critical to accurately estimate the pre-stressed anchor support parameters for surrounding rock reinforcement;otherwise,engineering disasters may *** paper presents a support parameter selection method that aims to allow deformation as a co.trol objective,which was applied to the tunnel located in Muzailing Highway,Min co.nty,Dingxi City,Gansu Province,*** theoretical analysis,we have identified five factors that influence pre-stressing *** selection of mechanical parameters for the rock mass was carried out using an inverse analysis *** with the measured data,the maximum displacement error of the numerical simulation results was only 0.07 *** length of anchor cable,circumferential spacing of anchor cable,longitudinal spacing,and pre-stress index are adopted as the input parameters for the support vector machine neural network model based on particle swarm optimization(PSO-LSSVM).Besides,the vault subsidence and the maximum deformation of surrounding rock are co.sidered as output values(performance indices).The goodness of fit between the predicted values and the simulated values exceeds ***,all support parameters within the acceptable deformation range are *** optimal support variables are derived by co.sidering the co.struction co.t and *** field application results show that it is feasible to co.struct the sample database utilizing the numerical simulation approach by taking the displacement as the co.trol target and using the neural network to specify the appropriate support parameters.

关键词： Displacement co.trol theory Anchorage support parameters Numerical simulation PSOLSSVM Tunnel co.struction

Microstructure and Properties of SiCp/Al co.posite Materials Fabricated via Powder Packed Resistance Additive Manufacturing

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稀有金属材料与工程 2024年第11期53卷 3035-3045页

作者： Wang Wenqin Chen Jigen Yan Xiaosong Han Zhaoxian Lin Gang Chen Jie School of Mechanical and Electrical engineering Nanchang UniversityNanchang 330031China Institute of special Equipment Inspection and Research Jiangxi General Institute of Testing and CertificationNanchang 330029China Jiangxi Sinohexaco.Helico.ter co. LtdJingdezhen 333032China Jiangxi Haoyu Heavy Industry co. LtdRuijin 341000China

SiC particle(SiCp)/Al co.posite materials were fabricated via powder packed resistance seam welding additive *** influence of welding speed on microstructure and mechanical properties of the specimen was investigated,elucidating the formation and fracture mechanism of single-pass multi-layer *** results demonstrate that a dense internal structure of the specimen characterized by uniformly dispersed SiCp embedded within the Al matrix is ***,particle agglomeration and porosity defects are *** porosity increases with the increase in welding speed,and the microstructure of the RSAM-24 specimen has the highest density,characterized by a density of 2.706 g/cm^(3)and a porosity of 1.672%.The mechanical properties of the specimens decrease as the welding speed *** mechanical properties are obtained when the welding speed is set as 24 cm/***,the average hardness,tensile strength and elongation values are 463.736 MPa,52.16 MPa and 2.2%,*** tensile specimens predominantly exhibit fracture along the interlayer bonding interface and the interface between the Al matrix and SiC particles,and the damage mode is ductile fracture.

关键词： additive manufacturing resistance seam welding SiCp/Al hardness welding speed

Analysis of internal crack in a six-ton P91 ingot

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China Foundry 2016年第3期13卷 191-198页

作者： Jing-an Yang Hou-fa Shen Bai-cheng Liu Ya-dong Xu Yong-ping Hu Bing-wang Lei School of Materials Science and engineering Tsinghua University special Material Institute Inner Mongolia North Heavy Industries Group Co. Ltd.

P91 is a new kind of heat-resistant and high-tensile steel. It can be extruded after ingot casting and can be widely used for different pipes in power plants. However, due to its mushy freezing characteristics, a lack of feeding in the ingot center often generates many defects, such as porosity and crack. A six-ton P91 ingot was cast and sliced, and a representative part of the longitudinal section was inspected in more detail. The morphology of crack-like defects was examined by X-ray high energy industrial CT and reco.structed by 3D software. There are f ive main portions of defects larger than 200 mm^3, four of which are interco.nected. These initiated from co.tinuous liquid f ilm, and then were torn apart by excessive tensile stress within the brittle temperature range(BTR). The 3D FEM analysis of thermo-mechanical simulation was carried out to analyze the formation of porosity and internal crack defects. The results of shrinkage porosity and Niyama values revealed that the center of the ingot suffers from inadequate feeding. Several criteria based on thermal and mechanical models were used to evaluate the susceptibility of hot crack formation. The Clyne and Davies' criterion and Katgerman's criterion successfully predicted the high hot crack susceptibility in the ingot center. Six typical locations in the longitudinal section had been chosen for analysis of the stresses and strains evolution during the BTR. Locations in the defects region showed the highest tensile stresses and relative high strain values, while other locations showed either low tensile stresses or low strain values. In co.clusion, hot crack develops only when stress and strain exceed a threshold value at the same time during the BTR.

关键词： hot crack industrial CT liquid film thermo-mechanical simulation steel ingot

Double-co.posite rectangular truss bridge and its joint analysis

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Journal of Traffic and Transportation engineering(English Edition) 2015年第4期2卷 249-257页

作者： Yongjian Liu Zhihua Xiong Yalin Luo Gao Cheng Ge Liu Jian Yang School of Highway Chang'an University cccc First Highway co.sultants co. Ltd. Department of Civil engineering The City College of New York Mc Laren engineering Group

This paper describes a novel co.posite tubular truss bridge with co.crete slab and co.crete-filled rectangular chords. With co.crete slab plus truss system and joints rein- forced with co.crete and Perfobond Leiste rib, double co.posite truss bridge proved to be a fairly suitable solution in negative moment area. Perfobond Leiste shear co.nector （PBL） is widely implemented in the co.posite structure for its outstanding fatigue resistance. In this pilot bridge, Perfobond Leister ribs （PBR） were installed in the truss girder＇s joints, which played double roles as shear co.nector and stiffener. An erection method and overall bridge structural analysis were then presented. Typical joints in the pilot bridge were selected to analyze the effect of PBR. Investigation of the effect of PBR in co.crete- filled tubular joints was elaborated. co.parison has revealed that co.crete-filled tubular joints with PBR have much higher co.straint capability than joints without PBR. For rect- angular tubular truss, the punching shear force of the co.crete filled joint with PBR is approximately 43% larger than that of the joint without PBR. Fatigue performance of the joint installed with PBR was improved, which was found through analysis of the stress co.centration factor of joint. The PBR installed in the joints mitigated the stress co.cen- tration factor in the chord face. Therefore, the advantages of this new type of bridge are demonstrated, including the co.venience of co.struction using rectangular truss, inno- vative co.cept of structural design and better global and local performances.

关键词： bridge engineeringco.posite truss bridgeloint analysisPerfobond ribco.crete-filled tube

Effect of titanium on the wettability between Fe-P-Ti alloy and Al2O3 substrate

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Progress in Natural Science:Materials International 2024年第3期34卷 555-561页

作者： Rui Wang Shengjie Bai Xu Chen Likui Xie Zhiqiang Yu Yang Kang Yihong Li Yong Hu Zhiyue Shi Zhijie Yan School of Materials Science and engineering North University of China Shanxi Key Laboratory of Advanced Metal Materials for special Environments North University of China CISDI engineering co. LTD. School of Materials Science and engineering Taiyuan University of Science and Technology

It is of significance that the wettability between the molten alloy and the Al2O3affects the inclusion removal,nozzle clogging and refractory erosion. In the present work, the wettability between the Al2O3substrate and Fe–P–Ti alloys with different Ti co.tent was investigated by using the sessile droplets method. The interfacial characteristics were investigated by scanning electron microsco.e（SEM）. The co.tact angles between the sintered Al2O3substrate and Fe–P–Ti alloys with 0, 0.05, 0.10 and 0.15 wt% Ti are 100.1°, 97.3°, 94.5°and 90.5°,respectively. The oxidation of [Al] and [Ti] in the molten alloys leads to the formation of the oxides on the droplets. With the increase of Ti co.tent in the Fe–P–Ti alloys, the formed oxides change from Al2O3to Tico.taining oxides. The reaction between [Ti] and Al2O3substrate in the interface results in the formation of Ti-co.taining oxides. The quantity of the interfacial oxides increases with the increase of Ti co.tent in the *** a result, the synergetic effect of the formation of the interfacial products and the oxides on the surface of droplets leads to the decrease of the co.tact angles between the Al2O3substrate and Fe–P–Ti alloys due to the increase of Ti co.tent.

关键词： Wettability co.tact angle Interfacial reaction Fe–P–Ti alloys Al2O3 substrate

A Load Calculation Method about Support Plates of Belt co.veyor Frames

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International Journal of Plant engineering and Management 2018年第4期23卷 242-246页

作者： PANG Zhining cccc Mechanical and electrical engineering co. Ltd.

Using tensile testing machine to test co.veyor belt tensile specimen about EP300-3×( 2 + 1.5)( this kind of belt is material of polyurethane,the tensile strength is 300 N/mm,three layers,the upper layer’ s thickness is 2 mm,the lower layer’ s thickness is 1. 5 mm),and it can get this kind material mechanics experiment data,the experiment data is about stress-strain of co.veyor belt,through taking experimental data into numerical simulation software,that is defined relevant calculation data of co.veyor belt material properties,and then it can analyze three situations about the frame has four support plates,six plates or eight plates,this experiment can co.clude the rules what is under the same tension,change of numbers and location of plates can influence the distribution and change of support force.

关键词： numerical simulation frame belt tension

Review on frost resistance and anti-clogging of pervious co.crete

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Journal of Traffic and Transportation engineering(English Edition) 2024年第3期11卷 481-496页

作者： Zhuo Wang Zhichen Liu Feng Zeng Kun He Shuaicheng Guo China Railway co.struction Group co. Ltd.Beijing 100040China State Key Laboratory of bridge Safety and Resilience College of Civil EngineeringHunan UniversityChangsha 410082China

Pervious co.crete is a special type of co.crete that is of high porosity and co.tains no or a small amount of fine aggregate,and it is an important basic material for sponge city *** presence of a large number of co.nected pores inside pervious co.crete leads to a marked difference in durability failure mechanism co.pared with that of ordinary *** this study,the frost resistance and anti-clogging of pervious co.crete were introduced in detail,and the methods to improve their performance were summarized *** cracking pattern of pervious co.crete is influenced by geometric characteristics and three-dimensional morphological features of pores,resulting in its crack generation,development,and geometry being significantly different from those of ordinary co.crete,thus leading to different freeze-thaw cycle *** addition,due to its different pore structure co.pared to ordinary co.crete,three types of clogging mechanisms,affecting the long-term permeability of pervious co.crete were elaborated systematically(i.e.,physical clogging,biological clogging,and chemical clogging).And the ways to improve the anti-clogging of pervious co.crete are systematically presented from multiple ***,in order to broaden the engineering applications of pervious co.crete,some research proposals are presented in this study.

关键词： Pervious co.crete co.nected pore Frost resistance Clogging mechanism