Journal articles: 'Speed Fastening'

1

Wang, Wei Ping, Dun Jin Cai, Xu Feng Ma, and Ping Wang. "Description of Subway DT Series Fastening." Applied Mechanics and Materials 644-650 (September 2014): 535–38. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.535.

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In recent decades, with the acceleration of population flowing in China, large and medium-sized cities to speed up the construction of urban rail. Relatively high speed railway, the requirement of the urban rail is relatively low, so it can be designed on the basis of high speed railway track structure for urban rail transport, this gives the designer the design of large space;Each city urban rail structure more or less differences. Especially fastening system is various, even in the same line also exist different fastening systems.Because Chinese fastening system in the subway is various, not a fixed is widely used fastening system;This paper, the DT series fastening in subway system has carried on the simple summary. Make a reference for fastening researchers.

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Sadeghi, Javad, Mohammad Fesharaki, and Amin Khajehdezfuly. "INFLUENCES OF TRAIN SPEED AND AXLE LOADS ON LIFE CYCLE OF RAIL FASTENING CLIPS." Transactions of the Canadian Society for Mechanical Engineering 39, no. 1 (March 2015): 1–11. http://dx.doi.org/10.1139/tcsme-2015-0001.

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Railway fastening clips play an important role in the stability and safety of railway track systems. There are various studies conducted on fastening clip failure mechanism. Although the majority of these studies indicate that fatigue is the main cause of clip failure, little attentions has been paid to parameters influencing clip fatigue characteristics. In response to this need, a new testing machine was developed by which the structural and loading conditions of fastening clips are simulated in a laboratory. Clip permanent deformations were measured for various track operational conditions, and consequently correlations were developed between clip plastic defamations and track axle loads as well as train speeds. The results obtained pave the way of determining the required clip maintenance cycles for various track loading conditions.

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Zhao, Xin, Jizhong Yang, Boyang An, Chao Liu, Yabo Cao, Zefeng Wen, and Xuesong Jin. "Determination of dynamic amplification factors for heavy haul railways." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, no. 2 (December 5, 2016): 514–28. http://dx.doi.org/10.1177/0954409716679203.

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A new approach has been developed to determine the dynamic amplification factors of railways. This approach employs a traditional multi-body dynamic model of vehicle–track interaction and a 3D explicit finite element model of wheel–rail rolling contact to treat the low- and high-frequency dynamics, respectively. Excitations are considered by contact surface unevenness and more specifically, by the power spectrum density of track irregularity for the low-frequency analysis and by the critical wheel flat, weld, and rail corrugation for the high frequency. For the 40-tonne axle load heavy haul railway simulated in this work, it has been found that the optimum fastening stiffness should be 150–200 MN/m; the dynamic amplification factors of the wheel–rail contact, fastening, and ballast forces are 1.94, 2.0, and 1.67, respectively, if the fastening stiffness of 200 MN/m is applied. Finally, new dynamic amplification factor formulae that include key parameters such as the fastening stiffness, speed, and axle load are proposed for the heavy haul railway design.

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Zhang, Haibo, Jinfeng Yang, Wei Tao, and Hui Zhao. "Vision method of inspecting missing fastening components in high-speed railway." Applied Optics 50, no. 20 (July 8, 2011): 3658. http://dx.doi.org/10.1364/ao.50.003658.

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Shang, Lei, Wen Bo Wang, Ting Ting Liu, Lei Cai, Hao Wang, and Zhen Dong Dai. "An Equipment Used for Studying the Vestibular Perception of Gekko gecko." Applied Mechanics and Materials 461 (November 2013): 570–76. http://dx.doi.org/10.4028/www.scientific.net/amm.461.570.

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The study of vestibule neurons specific firing mode of Gekko gecko under stimulus of different angles and rotating speeds has an important theoretical significance to reveal the control mechanism of Gekko geckos vestibular position as well as to the development of gecko-robots. A vari-angle rotating equipment was made to give different stimulus in study of Gekko geckos vestibular electrophysiology. The equipment mainly consisted of four parts as follows: fastening panel for stereotaxic instrument, shaft locking device, counterweight, driving system. The shaft locking device and counterweight realized tight fixation and torque equilibrium at different angles respectively. Fastening panel matched the general stereotaxic instrument. A stepper motor driver controlled the velocity and acceleration of rotation. Initial experiment verified that the equipment had superiority of easy operation, reliable positioning and accurate control of angle and speed, which indicated that it could meet the demand of the Gekko geckos vestibule research.

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Gorev, Vycheslav. "Ensuring explosion safety of residential buildings." MATEC Web of Conferences 193 (2018): 03046. http://dx.doi.org/10.1051/matecconf/201819303046.

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Explosions of air - and-gas mixtures in residential buildings – incident dangerous and recently extended. Unlike the production explosive buildings residential buildings are not protected by express requirements. In this work the possibility of protection of these buildings by means of a depressurization through the coming-off apertures is analyzed. These apertures can be closed by windows or express light-weight constructions. In work it is shown that fastenings of these designs in an aperture considerably are reduced by effectiveness of opening of apertures as the incipient state of driving of protective designs does not open space for venting of gases. Explosion pressure at the same time grows as in closed volume and until opening can reach critical value and cause destruction of the protecting and load-bearing frames. By the time of opening of an aperture for venting of gases the Safety design already has sufficient speed, and discovery of the area in that case happens quickly and pressure increases slightly. The main pressure boost happens before destruction of fastening of mild designs and at their driving in an aperture when volume can be considered pressure-tight. Calculations show: that designs with the specific surface density ρp≥30 kg/m2 and depth of seal of ≈0,2 m do not provide protection of residential buildings. The modern windows to double-glazed windows and their fastening are close to these conditions.

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Kruglov, Pavel V., and Irina A. Bolotina. "Technology of Manufacturing of Disk Blanks to High-Speed Elements for Tests on Anti-Meteoroid Protection." ITM Web of Conferences 35 (2020): 04013. http://dx.doi.org/10.1051/itmconf/20203504013.

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In this paper, a variant of the manufacturing technology of the disk blank for the segment liner of the shape charge is proposed. The charges are used to test the anti-meteorite stability of spacecraft. The proposed method makes it possible to form a blank in which, as its thickness decreases from the center to the periphery, a periodic profile variable in thickness is formed simultaneously in the circumferential direction. The disk metal blank is fixed in a three-cam chuck and the end face of the disk is cut with a decrease in thickness along the generatrix from the center to the periphery. Under the action of fastening forces, the disk blank is deformed and after processing the thickness in the cross section has a triangular periodic profile. Experiments on processing of disk preparations at various efforts of machine device are carried out. The dependences of the disc thickness on the fastening force in the device are obtained. After harmonic analysis of the thickness of the cross section, the values of the amplitudes of harmonics of different thickness in the circumferential direction at different distances from the center of the disk blank were determined. An increase in the fastening force leads to an increase in the amplitude of the third harmonic of the part thickness. It is shown that the change in the amplitudes of the first and second harmonics of different thickness is insignificant, and the amplitude of the third harmonic increases from the center to the periphery, which is caused by a decrease in the stiffness of the workpiece in the peripheral region.

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Liu, Yi, Heng Liu, Xin Wang, and Minqing Jing. "Nonlinear dynamic characteristics of a three-dimensional rod-fastening rotor bearing system." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, no. 5 (June 18, 2014): 882–94. http://dx.doi.org/10.1177/0954406214539471.

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The nonlinear dynamic characteristics of three-dimensional rod-fastening rotor bearing system are investigated in this paper. The rod-fastening rotor includes discontinuous shaft, rotating disks, circumferentially distributed rods, and macrointerfaces between disks. The first three parts are discretized by three dimensional elements, and the macrointerfaces are connected by some springs whose stiffness is determined by a proposed linear partition method. For comparison, the three-dimensional dynamic model of a corresponding complete rotor bearing system is also built. After the rod-fastening and complete rotor bearing system are reduced by a component mode synthesis, periodic motions and stability margins are calculated by using the shooting method and path-following technique, and the local stability of system is obtained by using the Floquet theory. Comparative results show the both systems have a resemblance in the bifurcation features when mass eccentricity and rotating speed are changed. The vibration response has the identical frequency components when typical bifurcations occur. The dynamic stress is obtained by regarding the displacements of all nodes as load. Moreover, the unbalanced and insufficient of the pre-tightening forces lead to obvious disadvantageous influence on the stability and vibration of the both systems. Generally, this paper considers the interfacial effect of the rod-fastening rotor bearing system and the relative nonlinear dynamic features are obtained.

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Yi, Qiang, Cai-you Zhao, Ping Wang, Xin Gao, Liu-cong Wang, and Wen-hua Ke. "Estimation of Rail Axial Force in High-Speed Railway Ballastless Track Based on Wave Modes." Mathematical Problems in Engineering 2019 (July 17, 2019): 1–11. http://dx.doi.org/10.1155/2019/4329830.

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To estimate the rail axial force of high-speed railway ballastless track, the reasonable index without complex measuring or error correction process is proposed. Taking the ballastless track structure in high-speed railway as the research object, the wave motion of periodic ballastless track is studied using the wave finite element method. It is found that some standing wave modes are linearly correlated with the rail axial force and thus can be considered as the basic indices for rail axial force estimation. A further in situ experiment according to the modal test method is performed and the feasibility of different wave modes for estimating rail axial force is discussed. Experiment results show that the lateral wave mode coincides well with the theoretical result while there is a large difference for the vertical wave mode. To explicate the difference, the temperature-dependent properties of the fastening are tested additionally. Parametric analysis shows that the frequency shift of vertical wave mode is greatly affected by the fastening temperature-dependent characteristics including the rail pad, elastic pad, and fastener clamping force, while the frequency shift of lateral wave mode is mainly determined by the rail axial force.

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Zhao, J. J., X. B. Zhao, Xian Hui Li, Bin Zhang, Bo Wang, and Wei Zhang. "Fasteners State Detection System Based on Wireless Data Transfer Module." Applied Mechanics and Materials 513-517 (February 2014): 3924–27. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.3924.

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The safety requirements demanded from rail traffic have risen above all in view of the rapid development of modern high-speed trains. Railway fastener is the important part of rail line. The normal state of the fastener is the guarantee of the rail transportation security. The missing or broken fastener may be the tremendous threaten to the security, or even cause the serious traffic accidents. This paper presents a new fully automatic and configurable wireless data transfer system able to detect the absence of the fastening bolts that fix the rails to the sleepers. The systems guarantee a high accurate detection for the missing or broken fastening elements in combination with the strain measurement of the rubber pad under rail.

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Cui, Hao, Qingwu Hu, and Qingzhou Mao. "Real-Time Geometric Parameter Measurement of High-Speed Railway Fastener Based on Point Cloud from Structured Light Sensors." Sensors 18, no. 11 (October 29, 2018): 3675. http://dx.doi.org/10.3390/s18113675.

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With the increase in the number of service years for high-speed railways, the foundation of the rail track suffers from settlement, which causes rail track irregularity. To adjust the position of the track and meet track regularity demands, several components of the fastening system will be replaced by different sized components. It is important to measure the exact geometric parameters for the components of a fastening system before adjusting the track. Currently, the measurement process is conducted manually, which is laborious and error-prone. In this paper, a real-time geometric parameter measurement system for high-speed railway fastener based on 2-D laser profilers is presented. Dense and precise 3-D point clouds of high-speed railway fasteners are obtained from the system. A fastener extraction method is presented to extract fastener point cloud and a region-growing algorithm is used to locate key components of the fastener. Then, the geometric parameter of the fastener is worked out. An experiment was conducted on a high-speed railway near Wuhan, China to verify the accuracy and repeatability of the system. The maximum root-mean-square-error between the manual measurement and the system measurement is 0.3 mm, which demonstrates adequate accuracy. This system can replace manual measurements and greatly improve the efficiency of geometric parameter measurements for fasteners.

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Chernobryvko, Marina, Konstantin Avramov, Boris Uspensky, Anatoly Tonkonogenko, and Leopold Kruszka. "Thermo-elastic-plastic Model for Numerical Simulation of Fasteners Destruction Under Gasodynamic Impulsive Pressure." EPJ Web of Conferences 183 (2018): 01039. http://dx.doi.org/10.1051/epjconf/201818301039.

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Modern rocketry widely employs a method of gasodynamic impulse destruction of bondings which may occur at high variety of temperatures. To design fasteners correctly it is necessary to have the ability to calculate fastener’s destruction time at a given pressure. Numerical research is an expedient approach to this problem. A mathematical model of a high-speed deformation and failure in fastening elements of special rocket structures due to gasodynamic wave-impact impulse loading is developed. A technique for numerical analysis of the deformation of fasteners and failure duration is proposed. To perform such analysis a set of factors such as: static stress-strain state due to assembling; thermo-elastic deformation of fasteners due to environment temperature; high-speed dynamical elastic-plastic failure of fastening elements are taken into consideration. The failure model due to the plastic flow considers dynamical material properties. As a criterion of failure maximum plastic deformation is chosen. The technique is implemented for several types of fasteners. Numerical simulation using finite elements method is conducted. The results of the numerical research are well-correlated with experimental data.

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13

Ren, Chun Yu. "Fast Tabu Search Algorithm for Capacitated Vehicle Routing Problem." Advanced Materials Research 760-762 (September 2013): 1790–93. http://dx.doi.org/10.4028/www.scientific.net/amr.760-762.1790.

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This paper studies the capacitated vehicle routing problem. According to the characteristics of model, fast tabu search algorithm is used to get the optimization solution from the overall situation. Firstly, it designs three operations for fastening the speed of convergence and efficiency. Finally, the good performance of this algorithm can be proved through a set of standard test problems.

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Wang, Xiang Guo, and Masayuki Yamamoto. "A Study on Fastening the Switching Speed for Wide Bandgap Semiconductor Based Super Cascode." Materials Science Forum 963 (July 2019): 823–26. http://dx.doi.org/10.4028/www.scientific.net/msf.963.823.

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The Super Cascode is a series connected structure with a normally-off low voltage Si-MOSFET and multiple normally-on wide bandgap semiconductors. It has low switching losses compared with silicon based bipolar devices, and low on-resistance and low cost compared with other single high voltage normally-off wide bandgap semiconductor devices. In practice, however, there are inevitable parasitic inductances, which result in the increase of switching losses. The method is proposed to eliminate the common-source inductances (CSIs), such as using stack-die configuration with each device and adding an additional inductance in the gate loop of Si-MOSFET. It is numerically shown that the rise and fall times of the proposed method were 33.5% and 7.2% faster than the conventional one, respectively.

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15

Yu, Miao, Wei-dong Wang, Jin-zhao Liu, and Shan-chao Sun. "The transient response of high-speed wheel/rail rolling contact on “roaring rails” corrugation." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 233, no. 10 (February 2, 2019): 1068–80. http://dx.doi.org/10.1177/0954409719825682.

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A high-speed wheel/rail finite element model is developed to focus on the non-steady-state rolling contact. The wheel/rail contact is solved based on the surface-to-surface contact algorithm, and the explicit finite element method is used to simulate the dynamic high-speed wheel/rail rolling contact. Considering the track–vehicle coupling system dynamics and the wheel/rail geometric nonlinearities, the wheel/rail contact on the short wave rail corrugation under the high-frequency vibration and the influence of train passing frequency on the track–vehicle system dynamics are studied. The explicit finite element method can be used to simulate the non-steady-state rolling contact process of the high-speed wheel/rail. After the initial load condition, the wheel/rail contact state tends to be stable in a short period of time. The short wave corrugation causes the high-frequency vibration of the track–vehicle system; the slightly advanced phase of the wheel/rail contact force promotes the development of rail corrugation in the rolling direction. When the train passing frequency is close to the rail pinned–pinned frequency, the pinned–pinned resonance occurs. The overall vibration near the fastening is relatively large and accelerates the damage of components. The longitudinal force is clearly affected by the traction torque with a periodic wheel/rail stick-slip vibration. The pinned–pinned resonance will promote the sliding wear at the wave trough near the fastening and it will become severe with the increase of the traction.

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Liu, Ji Xin, Feng Ju Hu, Ji Dai Wang, and Yuan Yuan Xu. "Study on Design of Cable Automatic Mounting Vehicle Structure." Advanced Materials Research 588-589 (November 2012): 170–72. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.170.

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In the process of the coal technology development, anchor installation speed is one of the main factors that affect the rapid excavation. The anchor cable automatic mounting vehicle, which is developed on the basis of this, is a set of borehole, anchor installation, fastening, tensioning and other operations. It effectively improve the efficiency of anchor cable supporting. This paper mainly introduces the working principle, the main structure design and functional characteristics.

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Bian, Kan, Chunhua Zhou, Fagang Zhao, Yipeng Wu, and Ke Xiong. "Investigation of a shape memory alloy releasable mechanism applied in space environment." International Journal of Applied Electromagnetics and Mechanics 64, no. 1-4 (December 10, 2020): 393–401. http://dx.doi.org/10.3233/jae-209345.

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Though the conventional pyrotechnic fastener mechanisms are widely used in spacecraft for their reliable releasable-fastening function, they still have several unavoidable problems: physical shock, high maintenance cost, to name a few. This paper introduces a new type of smart releasable mechanism based on a Shape Memory Alloy (SMA) spring and its corresponding heating apparatus. To obtain the high heating efficiency and increase the response speed, the SMA spring is transitionally fit with the heating apparatus shell instead of directly heating by electric current. As soon as the heating apparatus begins to work, the SMA spring will provide an un-locking force to release the fastening device within the standard time, which also realizes the similar releasable-fastening function comparing with the conventional pyrotechnic fastener mechanisms. In order to ensure the reliability of space products, the heating apparatus is composed of two identical ceramic heating elements which can be controlled independently or synchronously. Finally, the experimental results clearly show that, under the satellite power supply at the constant value of 28 V, the SMA spring can reach the desired 30 N unlocking force within 93 s and 51 s by single or dual heating elements, respectively. The maximal output force can even be increased as large as 40 N under the limited volume of the releasable mechanism.

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Spengler, Arnim Johannes, Panagiotis Spyridis, Tobias Bruckmann, Alexander Malkwitz, and Dirk Schlüter. "Discussion on Applicability and Requirements for the Installation of Fastenings Using Robot Systems in the Construction Industry." Periodica Polytechnica Architecture 51, no. 1 (May 28, 2020): 1–8. http://dx.doi.org/10.3311/ppar.15309.

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Since robotics is becoming increasingly widespread in the construction industry, more phases and working steps should be investigated for their applicability to automation. Ideally, only few robot systems would be needed and thus be multifunctional.Current robot systems are used almost exclusively in precast construction. At the construction site, only prototypes are in use, and only individual parts of the building shell construction and assembly can be handled.This paper examines to what extent robots can be applied for the installation of fastenings and which boundary conditions exist or need to be addressed. Automated construction, and more precise installation of fastenings, has been partially implemented, which has been shown to increase productivity as well as installation quality, and therefore the components’ structural safety. This knowledge must now be extended to robots. The present work is based on an overview of current research and development and includes a discussion on the current research at the University Duisburg-Essen on a cable robot for brickwork construction. It further demonstrates that fastenings pose an important additional application, especially to ensure the changeover to other building materials. These can be built-in parts, but also brickwork connections or prefabricated parts.It can be assumed that robots will become increasingly important in the construction industry for reasons that include high quality, safety, speed and economic aspects.This is an extended paper of the Creative Construction Conference in Budapest on “Examination of Advanced Fastening Systems for the use of Robots in the Construction Industry” (Spyridis et al., 2019).

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Xiao, Xinbiao, Xuesong Jin, and Zefeng Wen. "Effect of Disabled Fastening Systems and Ballast on Vehicle Derailment." Journal of Vibration and Acoustics 129, no. 2 (August 12, 2006): 217–29. http://dx.doi.org/10.1115/1.2424978.

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The effect of disabled fastening systems and ballast on railway vehicle derailment is investigated by developing a nonsymmetrical coupled vehicle/track model. In the model a half passenger car is considered, and modeled with a multi-body system with 18 degrees of freedom, which runs on a tangent track at a constant speed. The tangent track is modeled as two elastic beams by discrete nonsymmetrical supporters modeling fastening systems, sleepers, and ballasts. The normal contact forces between wheels and rails are described by Hertzian elastic contact theory, and the tangential forces by the nonlinear creep theory of Shen et al. (Proceedings of the 8th IAVSD Symposium, Cambridge, MA, pp. 591–605). In the numerical analysis, the disabled rail fastening, rail pad, and ballast, on one and two sides of the track are, respectively, considered. Through a detailed analysis, derailment coefficients and the track state variations are obtained. The derailment coefficients are defined as the ratio of the lateral force to the vertical force of the wheel and rail (indicated by L∕V), duration of L∕V, and rate of the wheel load reduction (indicated by ΔV∕V), respectively. The variations of the contact points on the wheel treads, the track gauge, the track cross-level, and rail turnover angle are present in the paper. The numerical results obtained indicate that the failure of rail supports has a great influence on the vehicle running safety.

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Sivam, S. P. Sundar Singh, Krishnaswamy Saravanan, Nagaraj Pradeep, Karuppiah Sathiya Moorthy, and Sankarapandian Rajendrakumar. "Grey Relational Analysis and Anova to Determine the Optimum Process Parameters for Friction Stir Welding of Ti and Mg Alloys." Periodica Polytechnica Mechanical Engineering 62, no. 4 (June 25, 2018): 277–83. http://dx.doi.org/10.3311/ppme.12117.

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The welding of Magnesium and Titanium and its alloys has continuously depicted a good challenge for designers and technologists. Ti and Mg alloys, particularly heat-treatable alloys, are difficult to join by fusion fastening techniques. The welding of dissimilar alloy such as Ti (Grade 2) and Mg (AZ91D) Alloy is an important problem during Friction Stir Welding (FSW). In this paper, the influence of Rotation speed (Rpm), Travel Speed (mm/min), Bottom Diameter Tool Pins (mm) and Tool Profiles of Ti and Mg alloy during FSW was investigated by Grey Relational Analysis and Anova was used to work out the foremost important Travel speed and feed rate affecting the Response. The primary and cooperation impact of the information factors on the normal reactions are examined. The expected values and measured values are genuinely close.

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Kossakowski, Paweł, Wiktor Wciślik, and Michał Bakalarz. "Failure of the overhead crane runway." MATEC Web of Conferences 284 (2019): 09001. http://dx.doi.org/10.1051/matecconf/201928409001.

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The paper reports a failure of the overhead crane runway. Failures of this type often occur in industrial buildings that have been in operation for a long period of time. The reasons are dynamic, fatigue-related phenomena in crane operations, and also design and structural errors. An important issue is also the presence of geometric notches, which promote the formation of fatigue cracks, accelerating the process of degradation of the structure. Visual inspection of the overhead crane runways revealed loosening and failure of rail – beam connections, and also substantial horizontal and vertical displacements of the rails. Additionally, geodetic measurements of rail arrangement were taken. They indicated the exceeding of permissible deviations for rails spacing and vertical arrangement stated in the relevant standards. The runway damages resulted from dynamic character of the loads applied. In some cases, high crane travel speed and acceleration produced impact forces that affected the runway structure. Vertical and horizontal deformation of rails was an additional source of impact in the crane runs. Another contributing factor was inappropriate design of rails and beams fastening, and also insufficient number of rail dilatations. A repair program was proposed which involved the use of additional rail fastenings and dilatations.

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Menz, Hylton B., Maria Auhl, and Shannon E. Munteanu. "Effects of Indoor Footwear on Balance and Gait Patterns in Community-Dwelling Older Women." Gerontology 63, no. 2 (September 3, 2016): 129–36. http://dx.doi.org/10.1159/000448892.

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Background: Footwear worn indoors is generally less supportive than outdoor footwear and may increase the risk of falls. Objective: To evaluate balance ability and gait patterns in older women while wearing different styles of indoor footwear: a backless slipper and an enclosed slipper designed to optimise balance. Methods: Older women (n = 30) aged 65-83 years (mean 74.4, SD 5.6) performed a series of laboratory tests of balance ability (postural sway, limits of stability, and tandem walking, measured with the NeuroCom® Balance Master) and gait patterns (walking speed, cadence, and step length, measured with the GAITRite® walkway) while wearing (1) socks, (2) backless slippers with a soft sole, and (3) enclosed slippers with a firm sole and Velcro® fastening. Perceptions of the footwear were also documented using a structured questionnaire. Results: Significant overall effects of footwear were observed for postural sway, the limits of stability test (directional control), the tandem walk test (step width and end sway), and temporospatial gait patterns (walking speed, cadence, and step length). No footwear effects were observed for maximum excursion when performing the limits of stability test or for speed when performing the tandem walk test. Post hoc tests indicated that performances were best while wearing the enclosed slippers, intermediate with socks, and worst with backless slippers. The enclosed slippers were perceived to be more attractive, comfortable, and well fitted, but heavier than the backless slippers. Most participants (n = 23; 77%) reported that they would consider wearing the enclosed slippers to reduce their risk of falling. Conclusion: Indoor footwear with an enclosed heel, Velcro® fastening, and a firm sole optimises balance and gait compared to backless slippers, and is therefore recommended to reduce the risk of falling.

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Ren, Chun Yu. "Fast Tabu Search Algorithm for Solving Multi-Vehicle and Multi-Cargo Loading Problem." Advanced Materials Research 655-657 (January 2013): 2397–400. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.2397.

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This paper studies multi-vehicle and multi-cargo loading problem under the limited loading capacity. According to the characteristics of model and problem, fast taboo search algorithm is used to get the optimization solution from the overall situation. Firstly, it applies newly improved insertion method to construct initial solution in order to improve the feasibility of the solution. Secondly, it centers cubage-weight balance to design three operations for fastening the speed of convergence, stock elite to improve the searching efficiency of algorithm. Finally, the good performance of this algorithm can be proved by experiment calculation and concrete examples for solving practical problems.

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Wei, Jiahong, Chong Liu, Tongqun Ren, Haixia Liu, and Wenjing Zhou. "Online Condition Monitoring of a Rail Fastening System on High-Speed Railways Based on Wavelet Packet Analysis." Sensors 17, no. 2 (February 8, 2017): 318. http://dx.doi.org/10.3390/s17020318.

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Xu, Qing Yuan, and Bin Li. "Study on Spatial Mechanical Characteristic of High-Speed Railway Ballastless Slab Track on Subgrade." Advanced Materials Research 503-504 (April 2012): 1010–15. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1010.

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By using beam element to model rail, spring element to model fastener, solid element to model different components of ballastless track, contact element to model the connection between each component of ballastless track, a statics three-dimensional nonlinear finite element mechanical model for calculating the forces transmission among rail, fastening and different component of ballastless slab track on subgrade was established. Experimental data of Suining-Chongqing railway line was given to validate the calculation model. Force of ballastless slab track on subgrade under gravity load, train load, uneven settlement load, temperature gradient load as well as combined load was analyzed. Results show that: spatial forces characteristic of ballastless slab track is very notable under train load; uneven settlement load as well as temperature gradient load has significant influence on the mechanical characteristic of ballastless slab track; force of ballastless slab track increases significantly under combined load than that of under any single load.

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Smirnov, V. I., and S. A. Vidiushenkov. "On equilibrium slope of station gradient." Proceedings of Petersburg Transport University 17, no. 4 (December 2020): 575–82. http://dx.doi.org/10.20295/1815-588x-2020-4-575-582.

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Objective: Defi nition of slope gradient for station track profi le elevation at which self-induced runningoff of loose running stock. Methods: Simulation of rolling stock movement based on analytical solution of differential equation of equilibrium of cut of wagons. Cut of wagons on station track is treated as a solid on a gradient plane with a mass equal to the mass of the cut of wagons. Track profi le elevation is approximated by piecewise-linear right line. Results: The paper shows that hopper wagons have the highest probability of self-induced running-off due to high air resistance coeffi cient. For three-element profi le the hypothetic wind speed at which running-off of wagons is possible remains relatively low, about 14 metres per second, which leaves the problem of effective fastening of wagons at stations still current. Practical importance: The solution obtained permits evaluating the probability of running-off of loose rolling stock under the action of gravity and under the impact of wind loading, as well as refi ne the norms for fastening of wagons at a station. The proposed calculation scheme also permits gauging the strength with which moving wagons would impact the backing thrust in case it is installed at the end of a track section.

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Gao, Xiaogang, Anbin Wang, Yu He, and Xiaohan Gu. "Structural Improvement of the ω-Type High-Speed Rail Clip Based on a Study of Its Failure Mechanism." Shock and Vibration 2019 (July 21, 2019): 1–14. http://dx.doi.org/10.1155/2019/4127065.

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In the circumstances of high-speed railways, the wheel-rail vibration is significantly aggravated by polygonal wheel wear and rail corrugation, which subsequently leads to the wheel-rail interaction at higher frequencies and potential failure of the rail fastening. In this paper, a ω-type clip of the fastening in the CRH high-speed rail was used to investigate the failure mechanism. First, a dynamic wheel-rail coupling model and a finite element analysis of the rail clip were developed, from which the rail vibration frequency and modal frequencies of the clip with different installation torques were obtained. The experimental tests and modal simulation results were mutually verified. In addition, the real-time vibration measurement and the wheel-rail wear monitoring were carried out at a CRH high-speed railway site. It was found that the resonant frequencies of the ω-type clip in the installation condition coincided with the excitation frequencies of the wheel-rail interaction induced by wheel-rail wear. The high-frequency dynamic failure mechanism of a typical ω-type clip, W300-1, is put forward for the first time. Moreover, a high-frequency rail clip fatigue test system was designed and developed specifically for this study. The loading excitation frequency of the clip test used was set as 590 Hz, and the loading amplitude was 0.05 mm. After 125-minute operation of the test system, the clip was broken at the expected location predicted by the FEA model. The high-frequency fatigue test result further verified that the failure mechanism of the ω-type clip was due to the resonance of the clip with its excitation force from the wheel-rail interaction. Finally, the clip was then structurally improved taking into account the stiffness and mass, which led to its resonant frequencies shifting away from the high-frequency excitation range, hence avoiding resonance failure of the subject clip.

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He, Xiao Cong. "FEA of Fatigue Behaviour of Adhesively Bonded Joints." Advanced Materials Research 148-149 (October 2010): 753–57. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.753.

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Adhesive bonding is a high-speed fastening method which is suitable for joining advanced lightweight sheet materials that are hard to weld. Latest literature relating to finite element analysis (FEA) of fatigue behaviour of adhesively bonded joints is reviewed in this paper. The recent development in FEA of fatigue behaviour of adhesively bonded joints is described with particular reference to three major factors that influence the fatigue behaviour of adhesively bonded joints: failure mechanism, environmental effects and hybrid joining techniques. The main FE methods used in FEA of fatigue behaviour of adhesively bonded joints are discussed and illustrated with brief case studies from the literature.

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He, Xiao Cong, Dong Zhen, Hui Yan Yang, Guo Jin Feng, Bao Ying Xing, Feng Shou Gu, and Andrew Ball. "Experimental Free Vibration Analysis of Clinched Beams." Applied Mechanics and Materials 467 (December 2013): 338–42. http://dx.doi.org/10.4028/www.scientific.net/amm.467.338.

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Clinching is a high-speed mechanical fastening technique which is suitable for point joining coated and pre-painted sheet materials. In this study, an experimental measurement technique was provided for the prediction of the free vibration behavior of single-lap cantilevered clinched beams. The dynamic test software and the data acquisition hardware were used in the experimental measurement of the dynamic response of the single-lap cantilevered clinched beams. The frequency response functions of the clinched beams of different clinching number were measured and compared. The main goal of the paper is to provide a basis for further research on vibration based non-destructive damage detection in clinched beams.

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Han, Jiang Long, Ding Jun Wu, and Qi Li. "Vibration and Bridge-Borne Noise from Urban Rail Transit Trough Beam." Advanced Materials Research 255-260 (May 2011): 1806–9. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.1806.

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Vehicle-track-bridge dynamic interaction analysis is applied to compute local dynamic responses of a trough beam under urban rail transit train by mode superposition method. The modal acoustic transfer vectors (MATVs) are obtained by boundary element method. The bridge-borne noise at different field points is then computed based on the MATVs and Fourier spectra of the mode coordinate responses of the bridge. The numerical results show that the noise level is significantly affected by the train speed but hardly influenced by the fastening stiffness. The residents in the high-rise buildings near the bridge may be much affected by the bridge-borne noise.

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Goldman, Carl. "Design of crane runway girders for top running and underrunning cranes and monorails." Canadian Journal of Civil Engineering 17, no. 6 (December 1, 1990): 987–1004. http://dx.doi.org/10.1139/l90-110.

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This paper contains a review of crane characteristics such as speed, wheel loads, and runway tolerances. A review of the rails and fastening is made. The paper presents the design of runway girders and a discussion on the selection of various sections or built-up members. A comparison is made between various specifications for impact and fatigue loading. Deflection tolerances and long spans are discussed. Details of supports at columns are presented and discussed, in particular, poor details causing failure as well as those that have performed well over many years. This paper is useful for structural engineers designing heavy industrial structures. Key words: crane characteristics, runway girder design and supports.

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Assefa, Workuha Dagnew, and Juan Juan Ren. "Characteristic of Longitudinal Coupled Prefabricated Slab Track (LCPBT): Numerical Simulation Analysis of Uneven Sub Grade Performance." Applied Mechanics and Materials 501-504 (January 2014): 474–79. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.474.

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With in the development of high-speed railway countrys China is one of the competent use of ballast less track spreader and largely applied on sub grade, in order to ensure high speed, safe and comfortable run of the train, the sub grade structure must provide smoother and more stable support for the upper track structure, but the problems caused by non uniformity sub grade structure performance are increasingly prominent. There have many serious problems such as low precision of measurement, low degree of automation, compaction mechanism, sometimes consolidation time and high interference of human factors. This paper described as the structural characteristics of longitudinal coupled prefabricated slab track System similar to bögl from German, a model for static analysis has been developed. Based on the model, the slab track element is presented. This element includes rail, rail fastening, prefabricated slab, CA mortar, and base plate and sub grade.

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Polyakov, V. Yu, and Dang Ngoc Thanh. "Traffic safety and dynamic properties of the bridge deck of high-speed railway lines." Vestnik of the Railway Research Institute 77, no. 6 (December 30, 2018): 357–63. http://dx.doi.org/10.21780/2223-9731-2018-77-6-357-363.

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Abstract. High-speed lines are one of the safest modes of transport, despite the special conditions for moving the wheel along the rail. The urgent task is to ensure the sustainable motion of the wheel along the rail over the bridges in high-speed traffic. A feature of high-speed lines (HS lines) is the practical achievement of critical speeds that cause resonance of bridge deck structures. Cases of rolling stock derailments on high-speed lines are not frequent. The article provides information about rolling stock derailments on high-speed rail and its consequences. Standards for the stability of wheels on rails in various countries with high-speed rail were considered. On the bridges of high-speed lines there are not many elements of the track that are strong dampers — the roadbed, its base and ballast. Due to the lack of damping elements, the damping properties of the bridge deck are of great importance. When driving over the bridge with critical speeds causing near-resonance oscillations, the force in the wheel—rail contact may drop to zero with the risk of derailment. Insufficient damping poses a threat to traffic safety. Thus, one of the most important dynamic parameters — damping — is a problem for a ballastless track on high-speed railway bridges. Considerations are given for the correct determination of stiffness associated with damping and affecting the interaction of rolling stock and bridge deck. It is shown that in case of insufficient damping at the fastening points on the bridges, the risk of derailment increases due to a fall of the vertical force below the permissible limit at the wheel—rail contact. Results of computer performed experiments are presented, confirming that it is precisely the significant oscillations of the bridge deck structures that are a safety hazard, since when the first car passes, the force at the contact of the wheel and rail for the first wheelset is safe. Requirements for damping parameters are given, ensuring reliable contact of the wheel and rail with significant fluctuations in bridge deck structures on high-speed lines. Results are presented, showing the dependence of required damping on the stiffness of intermediate rail fasteners.

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He, Xiao Cong. "Finite Element Analysis of Adhesively Bonded Single-Lap Joints." Advanced Materials Research 129-131 (August 2010): 411–15. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.411.

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Adhesive bonding is a high-speed fastening technique which is suitable for joining advanced lightweight sheet materials that are dissimilar, coated and hard to weld. Major advances have been made in recent years in adhesive bonding technique. Latest literature relating to finite element analysis (FEA) of adhesively bonded single-lap joints (SLJs) is reviewed in this paper. The recent development in FEA of SLJs is described with particular reference to three major factors that influence the success of adhesive bonding technique: failure mechanism, environmental effects and mechanical behavior. The main FE methods used in FEA of SLJs are discussed and illustrated with brief case studies from the literature. Areas where further useful progress can be made are also identified.

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Liu, Fu Long, Xiao Cong He, and Lun Zhao. "A Performance Study of Clinched Joints with Different Material." Advanced Materials Research 887-888 (February 2014): 1265–68. http://dx.doi.org/10.4028/www.scientific.net/amr.887-888.1265.

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Clinching is a high-speed mechanical fastening technique for point joining of sheet material. In order to investigate the influence of material property on the mechanical property and failure mode of clinched joints, three types of clinched joints in aluminum alloy sheet were tested under tension-shear loading with MTS landmark, separately. Results showed that the property of the substrate had effective on the performance of clinched joints. Clinched joints had higher strength and good energy absorption capacity when the strength of the substrate was higher. The strength and energy absorption capacity of the clinched joints were evaluated via load-displacement curves. While the failure modes of clinched joints were all the same: neck facture failure.

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Lyubіn, Mykola, and Oleksіі Tokarchuk. "INFLUENCE OF THE METHOD OF FASTENING OF THE STRESSLESS TAGS TO THE THRESHOLD PROCESS." Vibrations in engineering and technology, no. 2(93) (May 31, 2019): 56–61. http://dx.doi.org/10.37128/2306-8744-2019-2-9.

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Introducing chipless taps into production it is necessary to take into account factors arising from the specifics of the method and factors affecting economic efficiency. Significant effect from the introduction of the machine method of manufacturing threaded holes in stainless steels with brushless taps can be obtained only if the complex of measures is observed, related to the choice of the optimum hole diameter and the quality of preparation of the hole for the thread, the choice of mounting the tap on the machine, the speed of thread extrusion, coolant equipment and others. A new contour design has been proposed in the paper to prevent damage to the instrument for the manufacture of internal threaded holes. In addition, the design allows to replace quickly the instrument to another size. The designed construction of the cartridge ensures the centering of the tool over the hole being machined and ensures the transmission of torque of the required size. Analytical dependencies and computational schemes that ensure the operability of the device are derived.

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Babu, Jalumedi, Nevin Paul Alex, Sonu P. Abraham, Jose Philip, BN Anoop, and J. Paulo Davim. "Development of a comprehensive delamination assessment factor and its evaluation with high-speed drilling of composite laminates using a twist drill." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, no. 12 (February 6, 2017): 2109–21. http://dx.doi.org/10.1177/0954405417690552.

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Composites are cutting edge engineering materials for modern high-technology products. Their heterogeneous structure entails processing defects uncommon with metallic parts. Drilling is a crucial manufacturing process to facilitate fastening and assembly of composite components. High-speed drilling especially is a promising technique to increase the productivity as well as the quality of the drilled hole. The severity of delamination damage around the drilled hole is a critical factor in the error-free performance of these parts in service. A new method to characterize the delamination induced by drilling with a comprehensive assessment factor called effective equivalent delamination factor is developed to overcome the limitations of other measures being used hitherto. The capability and appropriateness of effective equivalent delamination factor as a delamination assessment factor are verified from experimental results.

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Maoinser, Mohd Azuwan, Faiz Ahmad, and Safian Sharif. "Effects of Cutting Parameters on Hole Integrity when Drilling GFRP and HFRP Composites." Advanced Materials Research 845 (December 2013): 960–65. http://dx.doi.org/10.4028/www.scientific.net/amr.845.960.

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The demand for mechanical fastening in composite materials is increasing due to their potential in large assemblies, aerospace and automotive industries. In practice, small components are integrated into large assemblies drilling holes in composite materials. Drilling defect free holes in composite presents many challenges during part assembly and services. This study presents the effects of cutting parameters used for drilling holes in glass fiber reinforced polymeric (GFRP) composites and hybrid fiber reinforced polymeric (HFRP) composites. Both the composites plates of 3 mm thickness were fabricated using a hand lay-up technique for the purpose of evaluating the effects of parameters on the quality of drilled holes. The holes were drilled using a 5 mm solid carbide twist drill at different spindle speed and feed rate. The quality of holes was assessed with respect to damage factor (Fd) and surface roughness (Ra) of the drilled holes. Results showed that the HFRP composite experienced lower damage factor (Fd) as compared to GFRP composite at lower feed rate or spindle speed. Scanning electron microscopic (SEM) examination revealed that the occurrence of delamination, fiber pull-out and matrix cracking was accelerated in the drilled holes at high spindle speed and feed rate.

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He, Xiao Cong, Dong Zhen, Bao Ying Xing, Kai Zeng, Yan Fang Ding, Feng Shou Gu, and Andrew Ball. "Free Vibration Measurements of Single-Lap Cantilevered SPR Beams." Applied Mechanics and Materials 321-324 (June 2013): 33–36. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.33.

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Self-pierce riveting (SPR) is a new high-speed mechanical fastening technique which is suitable for point joining dissimilar materials, as well as coated and pre-painted materials. In this study, an experimental measurement technique was provided for the prediction of the free vibration behavior of single-lap cantilevered SPR beams. The dynamic test software and the data acquisition hardware were used in the experimental measurement of the dynamic response of the single-lap cantilevered SPR Beams. The frequency response functions of the SPR beams of different rivet number were measured and compared. The main goal of the paper is to provide a basis for further research on vibration based non-destructive damage detection in single-lap cantilevered SPR beams.

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40

Simone, Andrea, Claudio Lantieri, Valeria Vignali, Francesco Mazzotta, Michele Carpinone, Federico Cuppi, Marco Nanni, and Davide Davalli. "A risk assessment method for "Eurobalise" fastening system: managing the sensor/sleeper interaction in the high-speed railway infrastructure." Transportation Research Procedia 45 (2020): 384–93. http://dx.doi.org/10.1016/j.trpro.2020.03.030.

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41

Geng, Qinghua, Weiming Liu, and Yuan Dai. "Automated Visual Inspection of Multiple Missing Fastening Bolts on the Sides of High-Speed Train Body in Railway Maintenance." IEEE Access 8 (2020): 187060–71. http://dx.doi.org/10.1109/access.2020.3026212.

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42

Gao, Xiaogang, Anbin Wang, Lang Liu, Yu He, and Longhua Ju. "Analysis of failure mechanism of W1-type fastening clip in high speed railway and structure study of damping composite." Engineering Failure Analysis 118 (December 2020): 104848. http://dx.doi.org/10.1016/j.engfailanal.2020.104848.

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43

Hasanov, E., A. Mammadov, and H. Aliyev. "Calculation Method of Fastening the Upper Slope of the Land Bund for Erosion and Strength." Bulletin of Science and Practice 7, no. 6 (June 15, 2021): 140–45. http://dx.doi.org/10.33619/2414-2948/67/20.

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To protect the slopes of the ground dam from the devastating effects of wind waves, ice, water flow, precipitation and other factors, a number of engineering measures are provided. Based on this, an engineering decision is taken on the choice of materials for fastening structures, as well as methods for calculating their stability. When calculating the stability of the upper slope, two cases of a combination of loads and impacts are mainly considered. One of them is the reduction of the water level in the reservoir with maximum speed, and the other is the case when the water level in the reservoir is at the lowest operational level. The article investigates the processes of sliding of natural slopes of the upstream dam. Taking into account the combined action of the forces of filtering, weighing and vapor pressure, as well as the force of hydrostatic pressure to the level of dead volume. The equation for the stability coefficient of a circular-cylindrical slip of a uniform natural slope of the upstream dam has been obtained.

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44

Wang, Jian, Longfu Luo, Wei Ye, and Shenglan Zhu. "A Defect-Detection Method of Split Pins in the Catenary Fastening Devices of High-Speed Railway Based on Deep Learning." IEEE Transactions on Instrumentation and Measurement 69, no. 12 (December 2020): 9517–25. http://dx.doi.org/10.1109/tim.2020.3006324.

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45

Hu, Jian Long, Xue Yi Zhang, and Wen Fu Zhang. "Five-Phase Half-Controlled Bridge Commutation and Stabilizing Voltage Nd-Fe-B Permanent-Magnet Generator for Light Vehicle." Applied Mechanics and Materials 236-237 (November 2012): 1280–85. http://dx.doi.org/10.4028/www.scientific.net/amm.236-237.1280.

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Nd-Fe-B permanent-magnet generator provides DC power for the electrical equipment of light vehicle and charges the battery. The rotor of this generator is constructed by several fastening segments of Nd-Fe-B permanent-magnet material onto the iron core through pole shoes by nonmagnetic bolts with adjacent magnet segments opposed to each other in polarity, i.e. N poles and S poles arrayed alternately. When the rotor rotation, hence the magnetic field rotates, the armature winding cuts the magnetic line and produces electromotive force. The developed five-phase half-controlled bridge commutation and stabilizing voltage adjuster combines both functions of voltage stabilization, commutation, and output direct current (DC) with stable voltage. The instability of output voltage was overcome when the permanent-magnet generator for light vehicle ran at wide range of speed and load.

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46

Provornaya, Darya, Sergey Glushkov, and Leonid Solovyev. "Damping of vertical and horizontal transverse vibrations in the bridge span structures." MATEC Web of Conferences 216 (2018): 01015. http://dx.doi.org/10.1051/matecconf/201821601015.

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The paper considers the issues of vibration isolation of railway bridge units on high-speed lines and seismic protection using dynamic vibration dampers. The purpose of the research is to justify the efficiency of damping the dynamic vibrations of the bridge supports with seismic insulating support parts. The research methodology involves building mathematical models of the systems under consideration and their numerical analysis. The methods of structural mechanics and dynamics of structures were used for solving the assigned tasks. The basic mathematical dependences of the vibration system with two seismic masses were developed. The rolling stock was represented by concentrated forces moving along the span structure. As a result, a new scheme for dynamic damping of vibration of the bridge supports was proposed according to which the span structure used as the dynamic vibration damper has an additional fastening on a rigid abutment.

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47

Kuo, Kei Lin. "A Study on Ultrasonic Vibration Assisted Tapping of Titanium." Advanced Materials Research 47-50 (June 2008): 218–21. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.218.

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Tapping is a technique commonly employed to make internal threads in the fastening industry. However, sudden breakage of tool bits is the most undesirable event often encountered during thread tapping. In particular, this can most readily occur when making internal threads in blind-holes, especially holes smaller than M6. As such, any effort to prolong the life of the tap is both necessary as well as urgent. The present study tried to use the high frequency vibration generated by a piezoelectric actuator to make threads for the titanium alloy. The thread tapping process was analyzed in detail, involving the Taguchi experimentation method, in which an orthogonal array table, L3(34),was employed to design the experimental runs for use in this study. The effects of interacting processing parameters including the frequency of vibration, vibration amplitude, spindle revolution speed and cutting fluid used on the performance of the tapping process were examined. The result was compared with no ultrasonic-assisted tapping.

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48

Htet, K. M., A. L. Galinovskiy, A. A. Barzov, and A. A. Avtushenko. "COMPARATIVE ANALYSIS OF THE RESULTS OF THE HOMOGENIZATION OF NANOSUSPENSIONS BY THE METHOD OF ULTRA-JET TREATMENT." Spravochnik. Inzhenernyi zhurnal, no. 282 (September 2020): 13–19. http://dx.doi.org/10.14489/hb.2020.09.pp.013-019.

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The article considers the urgent problem of finding new highly effective methods for dispersing suspensions prepared using nanomaterials (boehmite, graphene, nanotubes). Based on comparative experimental data, it is shown that the ultra-jet treatment method has several advantages. For experiments, standard equipment for waterjet cutting of materials was used. A single crystal of diamond was used as a target for a high-speed nanosized suspension, the fastening of which was carried out in special technological equipment, which also performs the functions of collecting the treated liquid. The experimental results showed that the particle size after ultra-jet treatment exceeds the result of the traditional method of homogenization – ultrasonic treatment. An important result of the research was the establishment of the fact that the homogenization process begins at the stages of the passage of the nanosuspension through the focusing tube, and not only in the process of collision of the ultrajet liquid with the barrier.

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49

Kloiber, Michal, Mária Kotlínová, and Jan Tippner. "Estimation of wood properties using pin pushing in method with various shapes of the penetration pin." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 57, no. 2 (2009): 53–60. http://dx.doi.org/10.11118/actaun200957020053.

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The existing penetration methods for the identification of the density of wood that forms a part of structures do not make it possible to describe the density in the entire element profile but only on its surface. However, wood density changes throughout the profile which affects the accuracy of the density determination. The instruments used until now based on the principle of a pin shot into the material thus needed to be supplemented with a test during which the pin would be pushed at least to the centre of the measured element. Pins of 3 mm in diameter were manufactured with a special jig fastening them to a universal testing machine. Using the testing machine, the force required to push the pin in was measured at a constant travel speed. It has been found out that the mechanical work needed for the pin penetration correlates very well with the wood density determined in the surroundings of the place where the pin was pushed in.

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Mercy, J. Lilly, S. Prakash, P. Vijayalakshmi, and Putti Venkata Siva Teja. "Multi Response Optimization of Drilling Parameters during Drilling of Particle Board Using Grey Relational Analysis." Applied Mechanics and Materials 592-594 (July 2014): 530–33. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.530.

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Particle board serves numerous functions such as cabinetry, tabletops, shelving, wall & floor panels, etc. Though Particle boards are much cheaper compared to solid wood, machining the material by optimizing the process parameters is a big challenge. Drilling is the major operation during final assembly of particle board, where fasteners are used to join together to bring final shape to the product. In this paper, the operation parameters such as speed, feed, drill diameter has been considered during drilling operation performed on Particle board and the output responses-surface roughness of the drilled hole and the Thrust force acting on the board during drilling are measured. Good surface finish of the hole ensures reduction of localised stresses around the hole due to fastening. Reduced Thrust force contributes to lesser delamination in particle board. Hence minimisation of both surface roughness and delamination is desired and hence optimisation of both responses is done simultaneously using grey relational analysis.

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Journal articles on the topic 'Speed Fastening'

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