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RESEARCH ON abrasion OF DEBRIS FLOW TO HIGH-SPEED DRAINAGE STRUCTURE

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Applied Mathematics and Mechanics(English Edition) 2004年第11期25卷 1257-1264页

作者：陈洪凯唐红梅吴四飞 Institute of Geotechnical Engineering Chongqing Jiaotong University Chongqing 400074 P.R.China Key Laboratory for the Exploitation of Southwestern Resources & Environmental Disaster Control Engineering of Ministry of Education Chongqing University Chongqing 400044 P.R.China

As one weak topic in research of debris flow,abrasion of debris flow shortens obviously application life of control structure composed of ***_speed drainage structure,one of the most effective techniques to control giant debris flow disaster,has shortened one_third application life due to abrasion by debris *** on velocity calculation method founded by two_phase theory,research of abrasion mechanism of debris flow to high_speed drainage structure was *** mechanism includes both abrasion mechanism of homogeneous sizing and shearing mechanism of particle of debris flow to high_speed drainage trough *** abrasion equations of both sizing and particle were established by Newton movement theory of debris *** abrasion amount formula of the high_speed drainage trough structure is set up by dimensional *** to calculating in the formula is consistent with testing data in_situ,which is valuable in design of high_speed drainage structure.

关键词： debris flow two-phase liquid high-speed drainage structure abrasion abrasion amount

Orbital-abrasion-assisted Electroforming of Non-rotating Parts

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Journal of Wuhan University of Technology(Materials Science) 2011年第5期26卷 827-831页

作者：李学磊 Nanjing University of Aeronautics & Astronautics School of Mechanical & Electronic Engineering Shanghai Second Polytechnic University

A novel technique of electroforming with orbital moving cathode was carried out for the fabrication of non-rotating thin-walled *** technique features a large number of insulating and insoluble hard particles as a real-time polishing to the *** cathode moves,hard particles polish its surface and provide the nickel non-rotating parts with near-mirror ***,microstructure,surface roughness and micro hardness of deposits fabricated by novel method were studied in contrast with the sample produced by traditional electroforming *** analysis and experimental results showed that the novel technique could effectively remove the hydrogen bubbles and nodules,disturb the crystal nucleation,and refine the grains of *** mechanical properties were significantly improved over traditional *** micro-hardness of the layer was in a uniform distribution ranging from 345 HV to 360 *** was confirmed that this technique had practical significance to non-rotating thin-walled parts.

关键词： electroforming orbital cathode abrasion non-rotating parts

The effect of dynamic loading on abrasion of mulberry fruit using digital image analysis

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Information Processing in Agriculture 2017年第4期4卷 291-299页

作者： Fatemeh Afsharnia Saman Abdanan Mehdizadeh Mahmoud Ghaseminejad Mokhtar Heidari Department of Agricultural Machinery Engineering Ramin Agriculture and Natural Resources University of KhuzestanIran Department of Mechanics of Biosystems Engineering Ramin Agriculture and Natural Resources University of KhuzestanIran Department of Horticultural Science Ramin Agriculture and Natural Resources University of KhuzestanIran

The quality of fruits can be reduced due to some damages and impacts which occur during *** of the most important mechanical damages that can reduce the quality of ripe fruit quality is abrasion *** study focused on the effect of dynamic loading based on customary harvesting method on mulberry fruit *** this end,different maturity stage and storage regimes were *** quality parameters,firmness,total soluble solid(TSS),total anthocyanins content(TAC)and abrasion area were the measured *** results revealed that none of the surveyed factors were stable during the *** lightness(L^*),redness(a^*),yellowness(b^*),C^* value,firmness,TSS and TAC of immature and mature mulberry decreased during *** value of a^*,b^* and C^* increased as dropping height ***,L*value,firmness,TSS and TAC of mulberry fruit decreased at both maturity stages(immature and mature mulberry).Moreover,abrasion area increased at immature and mature mulberries by increasing the dropping height and storage time.

关键词： abrasion Dynamic loading Postharvest quality Mulberry

Effects on Structure and abrasion Resistance of GCr15 Steel by Surface Gas-Phase RE Diffused Permeation with Laser Melting Solidification

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High Technology Letters 2000年第4期6卷 29-32页

作者：许越 Chen Xiang Ji Hong Dept.of Applied Chemistry Harbin Insititute of TechnologyHarbin 150001P.R.China

The effects on abrasion resistance and the microstructure of GCr15 steel surface by the compound technology of permeating RE combined with laser melting modification was studied. The results show that after compound treatment, the abrasion resistance of samples has been improved significantly and the weight loss has been reduced to 14% of blank sample; the microstructure has been denser and more uniform than that of untreated; meanwhile, the grain has been refined and the concentration gradients of the elements permeated have been decreased obviously.

关键词： Rare Earth Laser melting modification abrasion

Study on abrasion Resistance of Modified Polypropylene Fiber Reinforced Cement

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Journal of China Textile University(English Edition) 2000年第2期17卷 37-39页

作者：高德川赵明杨序纲王依民 China Textile Univ Shanghai China

Modified polypropylene fiber reinforced cement compos-ites were investigated in their abrasion resistance andsurface morphology. The test results showed the addingof fiber could noticeably improve the abrasion resistanceof composite. The bonding and friction of fibers/cementwere the main contribution to abrasion resistance im-provement, which resulted from the surface morphologyobservation.

关键词： modified polypropylene fiber fiber reinforced cement abrasion resistance surface morphology

abrasion OF THE BOTTOM OUTLETS AND ITS REPAIR IN SANMENXIA PROJECT

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International Journal of Sediment Research 1991年第2期 1-12页

作者： WEI Yonghui Senior engineer, The Three Gorges Project Development Incorporated

The Sanmenxia Project completed in 1960 is a multi-purpose hydro project with emphasis on flood control. After the expounding, serious deposition occurs in the upstream part of the reservoir and the Weihe River. The project has to be rebuilt twice in the period from 1964 to 1978. Thus the discharge capacity is greatly enlarged by excavating two side tunnels on the left bank, converting three penstocks into sluice conduits and reopening & bottom outlets formerly used for di- version. By changing the operational mode from storing water year round to stor- ing clear water during the dry season and sluicing sediment during the flood season, the sediment problem of the reservoir is largely solved and multi-purpose benefits of the project are partially retained. But the heavy sediment load still caused serious abrasion on bottom outlets and turbines, particularly on the inlet gate slot, the service gate slot and the floor. Much effort has been made to clarify the mechanism of the damage and to choose abrasion-resistant material for repair. The repair of the bottom outlets has been going on since 1980. This paper describes the abrasion on the bottom outlets in details and the subsequent repair effected.

关键词： abrasion Sediment concentration Sediment-laden flow Cavitation abrasion-resistant material Bottom outlet.

Compressive Strength and abrasion Resistance of Concretes under Varying Exposure Conditions

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Open Journal of Civil Engineering 2017年第1期7卷 82-99页

作者： Adekunle P. Adewuyi Ismaila A. Sulaiman Joseph O. Akinyele Department of Civil Engineering Federal University of Agriculture Abeokuta Nigeria Department of Engineering Cappa and D’Alberto Plc Lagos Nigeria

The purpose of this study is to comparatively evaluate the wear resistance of concretes under abrasion rates. Five concrete mix proportions of a fixed water-cement ratio of 0.45 were considered in the study, but the constituent materials, age of concrete and exposure contact conditions were varied. The coarse aggregate type employed in the study was crushed granite. The compressive strength and abrasion resistance of concretes were tested between at ages 7 to 70 days and 100 - 500 revolutions of abrasion wheels respectively. The study revealed that the compressive strength and abrasion resistance had the optimal performance when the coarse aggregate content was 45% and the worst performance when the fine aggregate content was 28.7% of the total weight of concrete constituents. There was a remarkable loss of concrete particles to wear between 200 revs and 300 revs of abrasion wheel contact. Concrete grade in excess of 60 N/mm2 is required to resist abrasion beyond 200 revolutions of abrasion wheel contact on concrete specimens. Concretes investigated also showed weak resistance to deep abrasion at and above 300 revolutions of abrasion wheel contact.

关键词： Compressive Strength abrasion Resistance Concretes Crushed Granite Cement Content Durability

Simple Correlations between Rock abrasion and Other Significant Rock Properties for Rock Mass and Intact Quartzite

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Open Journal of Civil Engineering 2017年第2期7卷 194-207页

作者： Scott Ureel Moe Momayez Department of Mining & Geological Engineering University of Arizona Tucson AZ USA

Rock abrasion plays a significant role in geotechnical design, tunneling operations and the safety of foundations from scour. It is imperative to determine such properties of uniaxial compression strength (UCS), rock quality designation (RQD) and hardness for rock engineering to help determine the amount of scour at foundation locations in order to prevent structural collapse, wear on drilling tools and help predict unstable rock conditions. Current practice for estimating maximum rock abrasion is based on the Los Angeles abrasion test;however, more research is needed to provide a more accurate and compatible method for all subsurface materials used in mining and civil engineering projects. This report will provide simple correlations relating abrasion resistance to RQD, UCS, Geological Strength Index (GSI) and Rock Mass Rating (RMR) and shear strength of metamorphic rock (Quartzite). Methods, results, recommendations and conclusions are presented. The paper also introduces recommendations for future rock abrasion techniques and discusses the use of these correlations exhibiting strong relationships between the mentioned rock properties.

关键词： Rock abrasion RQD UCS Shear Strength LA abrasion

THE EFFECT OF, abrasion ON LOW STRESS MECHANICAL PROPERTIES OF FABRIC

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Journal of China Textile University(English Edition) 1990年第1期8卷 23-30页

作者：吕柏祥 R.Postle China Textile University The University of New South Wales Australia

The low stress mechanical properties of a pure wool and a wool / polyester blend twill fab-rics which were abraded at various abrasion cycles were measured using the KES-F system andthe Instron tensile machine. The surface change of fabrics before and after abrasion was stu-died by means of scanning electron microscope. With the increasing number of cycles, the re-covery behavior of the fabrics studied in tensile, shear and bending deformation decrease, theantibuckling ability lowers, the friction coefficient increases. The geometric roughness de-creases during the first step of abrasion then enhances with further abrasion. The influence ofabrasion on mechanical properties of the pure wool fabric are larger than that of blend fabric.

关键词： abrasion mechanical property fabric KES-F system Instron tensile machine