Journal articles: 'Effetto catenaria'

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Yao, Jiannan, and Xingming Xiao. "Investigation of Collision Behavior of Hoisting Catenaries during a Lifting Cycle in Coal Mines." Mathematical Problems in Engineering 2015 (2015): 1–16. http://dx.doi.org/10.1155/2015/640712.

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This investigation focused on the analyses of transverse vibrations of mine hoisting catenaries where collision between adjacent ropes is more likely to occur. To support the analyses of transverse vibrations of catenaries, theoretical correlation models for longitudinal tension and transverse vibration were first established. Based on a severe rope collision case, on-site measurements and numerical simulations were performed. The research results indicated that the external second-order excitation frequency induced by axial fluctuations of head sheave was the primary excitation frequency, which was closer to the resonance frequency. Furthermore, the effects of excitation amplitude and imbalanced tension were also investigated revealing that larger excitation amplitude contributes to larger response amplitude and the maximum response amplitude of a catenary is sensitive to imbalanced rope tension. Eventually, new solutions, which will facilitate hoisting catenary operation beyond the resonance frequency range, were proposed.

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TEICHMAN, J., and L. MAHADEVAN. "The viscous catenary." Journal of Fluid Mechanics 478 (March 10, 2003): 71–80. http://dx.doi.org/10.1017/s0022112002003038.

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A filament of an incompressible highly viscous fluid that is supported at its ends sags under the influence of gravity. Its instantaneous shape resembles that of a catenary, but evolves with time. At short times, the shape is dominated by bending deformations. At intermediate times, the effects of stretching become dominant everywhere except near the clamping boundaries where bending boundary layers persist. Finally, the filament breaks off in finite time via strain localization and pinch-off.

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Goela, J. S., N. Somu, R. Abedinzadeh, and R. Vijay Kumar. "Wind loading effects on a catenary." Journal of Wind Engineering and Industrial Aerodynamics 21, no. 3 (December 1985): 235–49. http://dx.doi.org/10.1016/0167-6105(85)90038-8.

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Zheng, Xue Xian, Xun Wang, Hong Bo Cheng, and Wen Hui Cao. "Lightning Protection Research and Simulation of High-Speed Railway Catenary." Advanced Materials Research 875-877 (February 2014): 1707–11. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.1707.

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The existing high-speed railway in China is erected on the viaduct. The traction power supply system of high-speed railway consists of catenary with auto-transformer (AT). The catenary above the rails is supported by towers besides the rails. As the increase of the height from top of towers to ground, the probability of the pilot discharging of lightning to catenary will increase. And the pilot striking distance to ground always remains constant. So the horizons shielding effects for catenary will decrese, and the whole catenary naked in the atmosphere extremely easily struck by thunderbolt. In the important places, e.g., substation and areas of frequent lightning, the lightning arrester is installed to limit lightning overvoltage. But the lightning arrester can limit local overvoltage only. In fact, high-speed railway struck by lightning has affected the safety of power supply system in China. So more reasonable lightning protection measures for Chinas high-speed railway will be studied in this paper.

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Chen, Guo, Yiren Yang, Yang Yang, and Peng Li. "Study on Galloping Oscillation of Iced Catenary System under Cross Winds." Shock and Vibration 2017 (2017): 1–16. http://dx.doi.org/10.1155/2017/1634292.

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This paper mainly aims at revealing the nature of the galloping oscillation of iced catenary system under cross winds. The aerodynamic force on the iced catenary system is assumed to be quasi-steady, and then the quasi-steady aerodynamic lift and drag coefficients are completed in FLUENT. By fitting the discrete simulation data, the expression of the vertical aerodynamic force is further obtained. According to the Den Hartog vertical galloping mechanism, the stability of iced catenary is discussed and the initial icing angle corresponding to the critical stability is obtained. On this basis, the dynamic model of the simple iced catenary system under cross winds is established. The partial differential vibration equation of the system is converted into the ordinary differential equation by the Galerkin method and then numerically solved. The condition of the unstable catenary motion in simulation is in agreement with that from theoretical stability analysis. In addition, the effects of structural damping, initial icing angle, and wind velocity on the system responses are investigated.

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Wang, Jiqiang. "Active Control of Contact Force for a Pantograph-Catenary System." Shock and Vibration 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/2735297.

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The performance of the high speed trains depends critically on the quality of the contact in the pantograph-catenary interaction. Maintaining a constant contact force needs taking special measures and one of the methods is to utilize active control to optimize the contact force. A number of active control methods have been proposed in the past decade. However, the primary objective of these methods has been to reduce the variation of the contact force in the pantograph-catenary system, ignoring the effects of locomotive vibrations on pantograph-catenary dynamics. Motivated by the problems in active control of vibration in large scale structures, the author has developed a geometric framework specifically targeting the remote vibration suppression problem based only on local control action. It is the intention of the paper to demonstrate its potential in the active control of the pantograph-catenary interaction, aiming to minimize the variation of the contact force while simultaneously suppressing the vibration disturbance from the train. A numerical study is provided through the application to a simplified pantograph-catenary model.

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Wang, Beining, Shaofang Wen, and Yongjun Shen. "LQR Active Control of Fractional-Order Pantograph-Catenary System Based on Feedback Linearization." Mathematical Problems in Engineering 2022 (October 21, 2022): 1–11. http://dx.doi.org/10.1155/2022/2213697.

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Fractional-order calculus has exclusive advantages in modeling the viscoelastic components with obvious fractional-order characteristics such as air springs and metal rubbers in the pantograph structure. In this paper, the air spring is tested, and fractional-order calculus is applied to the modeling of pantograph-catenary system of the high-speed train. The parameter identification method of fractional-order derivative is analytically derived. The traditional lumped mass model is improved and a coupling two-degree-of-freedom model of the fractional-order pantograph-catenary system is established. The fractional-order derivative term in the pantograph-catenary model is approximately calculated by the Oustaloup filter algorithm. Taking the time-varying nature into consideration, the catenary is treated as an extended variable to obtain an augmented model. On this basis, the system is linearized based on differential geometry theory, and an LQR controller is designed to control the pantograph-catenary system. The feedback linearized LQR control and PID control are used to control the same type of traditional pantograph, and the results are compared. Meanwhile, the control effects of feedback linearized LQR control under different pantograph parameters and at different train speeds are analyzed. The results show that the feedback linearized LQR control can present a much better control performance than PID control, and the pantograph-catenary contact force and pantograph head vibration amplitude are both reduced obviously. Even at different train speeds or under different pantograph parameters, it can also effectively reduce these control indexes and provide more robust control performance. These results help to put forward new control ideas and theoretical basis for the vibration control of the pantograph-catenary or similar dynamical system.

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Bryja, Danuta, and Adam Hyliński. "An influence of track stiffness discontinuity on pantograph base vibrations and catenary–pantograph dynamic interaction." Studia Geotechnica et Mechanica 42, no. 2 (June 30, 2020): 111–24. http://dx.doi.org/10.2478/sgem-2019-0035.

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AbstractIn this article, the computational methodology of the catenary–train–track system vibration analysis is presented and used to estimate the influence of vehicle body vibrations on the pantograph–catenary dynamic interaction. This issue is rarely referred in the literature, although any perturbations appearing at the pantograph–catenary interface are of great importance for high-speed railways. Vehicle body vibrations considered in this article are induced by the passage of train through the track stiffness discontinuity, being a frequent cause of significant dynamic effects. First, the most important assumptions of the computational model are presented, including the general idea of decomposing catenary–train–track dynamic system into two main subsystems and the concept of one-way coupling between them. Then, the pantograph base vibrations calculated for two train speeds (60 m/s, 100 m/s) and two cases of track discontinuity (a sudden increase and a sudden decrease in the stiffness of track substrate) are analyzed. Two cases of the railway vehicle suspension are considered – a typical two-stage suspension and a primary suspension alone. To evaluate catenary–pantograph dynamic interaction, the dynamic uplift of the contact wire at steady arm and the pantograph contact force is computed. It is demonstrated that an efficiency of the two-stage suspension grows with the train speed; hence, such vehicle suspension effectively suppresses strong sudden shocks of vehicle body, appearing while the train passes through the track stiffness discontinuity at a high speed. In a hypothetical case when the one-stage vehicle suspension is used, the pantograph base vibrations may increase the number of contact loss events at the catenary–pantograph interface.

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Jin, Mengzhe, Man Hu, Hao Li, Yixuan Yang, Weidong Liu, Qingyuan Fang, and Shanghe Liu. "Experimental Study on the Transient Disturbance Characteristics and Influence Factors of Pantograph–Catenary Discharge." Energies 15, no. 16 (August 17, 2022): 5959. http://dx.doi.org/10.3390/en15165959.

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The transient electromagnetic disturbance generated by arcing discharge between the pantograph and catenary can pose a significant risk to the safe operation of electrified railways. In order to better comprehend its properties, a pantograph–catenary discharge generating device is designed to simulate the discharge phenomenon with moving electrodes in this experimental investigation. The effects of the applied voltage, the gap distance, and the relative motion between the pantograph and catenary on the time- and frequency-domain features of the discharge current and electromagnetic field are investigated. The variation trends of pulse peak current, rise time, pulse repetition frequency, maximum amplitude, and characteristic frequency in the radiation spectrum are retrieved under varying experimental settings, and the effect mechanisms are derived from the physics of gas discharge. A dynamic discharge test is conducted in this study in order to further understand the effect of electrodes’ relative motion on discharge characteristics. The results indicate that lateral sliding motion of the pantograph along the track has a negligible effect on the transient discharge, whereas a faster vertical approaching motion between the pantograph and catenary generates a larger pulse current peak, a steeper rise front-edge, and a higher radiation intensity.

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Bocciolone, M., F. Resta, D. Rocchi, A. Tosi, and A. Collina. "Pantograph aerodynamic effects on the pantograph–catenary interaction." Vehicle System Dynamics 44, sup1 (January 2006): 560–70. http://dx.doi.org/10.1080/00423110600875484.

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Wu, Qirui, Xiaohan Phrain Gu, Ziyan Ma, and Anbin Wang. "A Study on the Vibration Characteristics and Damage Mechanism of Pantograph Strips in a Railway Electrification System." Machines 10, no. 8 (August 18, 2022): 710. http://dx.doi.org/10.3390/machines10080710.

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This paper presents the vibration characteristics of a pantograph–catenary interaction in a rigid catenary system. Both computational simulation and laboratory tests are carried out to evaluate the frequency contents of pantograph strips. Based on the observation that irregular wear is characterized by the consistency between the pantograph strips’ wear pattern and the mode shape of their dominant modal frequencies, it is deducted that resonance occurs at the pantograph strip and the contact wire interface in the high frequency range. By applying damping treatment to the pantograph strip, and hence improving its damping property, a reduction of 7 dB in the total vibration level at the sliding contact can be achieved, as verified through field tests. It is also found that the worse the initial condition of the pantograph–catenary system, the more prominent the damping effects on the control of high-frequency vibration for irregular wear problems.

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Wang, Tian Ying, Li Jun Yang, Zhi Gang Xu, and Jin Kun Liu. "Design and Comparison of Catenary and Taut Mooring Systems for New Concept FPSO IQFP in Shallow Waters." Applied Mechanics and Materials 353-356 (August 2013): 2670–75. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.2670.

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In order to design an effective and economical multi-point mooring system for the new concept FPSO IQFP (fillet inverted quadrangular frustum pyramid shaped FPSO, presented by the lead author), the effects of the mooring parameters on the performance of catenary mooring system and taut mooring system were investigated according to the initial design plans given in advance according to the steady environment forces and practical experiences. Then, the optimal mooring systems were developed on the basis of the static analysis results combined with the coupled calculations in time domain. Finally, the merits and demerits of the two mooring schemes were compared based on the mooring and static characteristic parameters as well as the curves of restoring force against horizontal displacement of the catenary and taut mooring systems respectively. The results verify that the taut mooring system is preferable to the catenary mooring system for IQFP deployed in shallow waters.

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Mansour, Achref, Othman Ben Mekki, Sami Montassar, and Giuseppe Rega. "Catenary-induced geometric nonlinearity effects on cable linear vibrations." Journal of Sound and Vibration 413 (January 2018): 332–53. http://dx.doi.org/10.1016/j.jsv.2017.10.012.

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Martorell, Miquel, Natalia Castro, Montserrat Victoriano, Xavier Capó, Silvia Tejada, Sara Vitalini, Raffaele Pezzani, and Antoni Sureda. "An Update of Anthraquinone Derivatives Emodin, Diacerein, and Catenarin in Diabetes." Evidence-Based Complementary and Alternative Medicine 2021 (September 20, 2021): 1–13. http://dx.doi.org/10.1155/2021/3313419.

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Diabetes is part of metabolic diseases and is characterized by high blood sugar levels over a prolonged period as result of an insulin-deficient production or an inappropriate response to insulin by our cells. This chronic disease was the direct cause of 1.6 million deaths in 2016 as reported by the World Health Organization. Emodin is a natural product and active ingredient of various Chinese herbs with the chemical formula 1,3,8-trihydroxy-6-methylanthraquinone. Diacerein is another naturally occurring anthraquinone (1,8-diacetoxy-3-carboxyanthraquinone) commonly used as commercial drug to treat osteoarthritis. These two anthraquinone derivatives have been shown to exert antidiabetic activities. Emodin seems to enhance the glucose tolerance and insulin sensibility via activation of PPARγ and modulation of metabolic-related genes. Diacerein seems to decrease inflammatory cytokines and increase insulin secretion enhancing insulin sensibility and therefore improving glucose control. Other naturally occurring anthraquinone derivatives, such as catenarin (1,4,6,8-tetrahydroxy-3-methylanthraquinone), have been shown to have antidiabetic activities although few studies have been performed. The synthesis of new emodin derivatives is increasing, but these new molecules have not been tested for diabetes treatment. In the current work, available literature on anthraquinone derivatives' effects in diabetes disease is reviewed. Moreover, we discuss the chemistry, food sources, bioavailability, and toxicity of the naturally occurring anthraquinone with antidiabetic effects.

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Faridmehr, Iman, and Mohammad Hajmohammadian Baghban. "An Overview of Progressive Collapse Behavior of Steel Beam-to-Column Connections." Applied Sciences 10, no. 17 (August 29, 2020): 6003. http://dx.doi.org/10.3390/app10176003.

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Local failure of one or more components due to abnormal loading can induce the progressive collapse of a building structure. In this study, by the aid of available full-scale test results on double-span systems subjected to the middle column loss scenario, an extensive parametric study was performed to investigate the effects of different design parameters on progressive collapse performance of beam-to-column connections, i.e., beam span-to-depth ratio, catenary mechanism, and connection robustness. The selected full-scale double-span assemblies consisted of fully rigid (welded flange-welded web, SidePlate), semi-rigid (flush end-plate, extended end-plate), and flexible connections (top and seat angle, web cleat). The test results, including load-deformation responses, development of the catenary mechanism, and connection robustness, are presented in detail. The finding of this research further enables a comprehensive comparison between different types of steel beam-to-column connections since the effects of span-to-depth ratio and beam sections were filtered out.

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Al Kazman, Bassam S. M., and Jose M. Prieto. "Friends or Foes? Cytotoxicity, HPTLC and NMR Analyses of Some Important Naturally Occurring Hydroxyanthraquinones." Nutraceuticals 1, no. 1 (October 18, 2021): 13–30. http://dx.doi.org/10.3390/nutraceuticals1010004.

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Hydroxyanthraquinones from plants have been used as both medicinal active ingredients and adulterants in slimming food supplements. Although sensible doses of certain natural hydroxyanthraquinones for laxative effects are generally safe in the short term, chronic intake has been related to tumorigenic, carcinogenic, and genotoxic effects. However, an increasing number of researchers are reporting the antiproliferative properties of the same ingredients in cancer cells, pointing towards a potential nutraceutical value for cancer prevention. Previous studies have evaluated anthraquinones’ anti-proliferative activity against various tumour cell lines and bioavailability in Caco-2 cells. However, there are scarce data about both their cytotoxicity in the later cell line and long-term stability. Therefore, this study will check the purity of several ‘aged’ samples using mutually complementary analytical techniques such as HPTLC and NMR assays as well as evaluate the anti-proliferative activity of the purest of these samples using the Caco-2 cell line. The chromatographic and spectroscopic analyses confirmed the long-term stability of those compounds, and their cytotoxic activity resulted in chrysazin (15 µg/mL) > catenarin (27.29 µg/mL) > rhein (49.55 µg/mL) > helminthosporin (52.91 µg/mL) > aloe-emodin (55.34 µg/mL). Our succinct review of the cytotoxicity of these compounds afforded two results: that this is the first clear report for catenarin being active in colon cancer cells and that this class of compounds needs to be better studied to clearly evaluate their benefit/risk profile in regard to both new chemo preventative nutraceuticals and anticancer therapies.

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Nakhaee, Ali, and Jun Zhang. "Trenching effects on dynamic behavior of a steel catenary riser." Ocean Engineering 37, no. 2-3 (February 2010): 277–88. http://dx.doi.org/10.1016/j.oceaneng.2009.10.005.

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YANG, Y. B., and JIUNN-YIN TSAY. "GEOMETRIC NONLINEAR ANALYSIS OF CABLE STRUCTURES WITH A TWO-NODE CABLE ELEMENT BY GENERALIZED DISPLACEMENT CONTROL METHOD." International Journal of Structural Stability and Dynamics 07, no. 04 (December 2007): 571–88. http://dx.doi.org/10.1142/s0219455407002435.

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This paper presents a two-node catenary cable element for the analysis of three-dimensional cable-supported structures. The stiffness matrix of the catenary cable element was derived as the inverse of the flexibility matrix, with allowances for selfweight and pretension effects. The element was then included, along with the beam and truss elements, in a geometric nonlinear analysis program, for which the procedure for computing the stiffness matrix and for performing iterations was clearly outlined. With the present element, each cable with no internal joints can be modeled by a single element, even for cables with large sags, as encountered in cable nets, suspension bridges and long-span cable-stayed bridges. The solutions obtained for all the examples are in good agreement with the existing ones, which indicates the accuracy and applicability of the element presented.

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Li, Chun Bao, Mingsheng Chen, and Joonmo Choung. "The Quasi-Static Response of Moored Floating Structures Based on Minimization of Mechanical Energy." Journal of Marine Science and Engineering 9, no. 9 (September 3, 2021): 960. http://dx.doi.org/10.3390/jmse9090960.

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It is essential to design a reasonable mooring line length that ensures quasi-static responses of moored floating structures are within an acceptable level, and that reduces the cost of mooring lines in the overall project. Quasi-static responses include the equilibrium position and the line tension of a moored floating structure (also called the mean value in a dynamic response), etc. The quasi-static responses derived by the classic catenary equation cannot present mooring–seabed interaction and hydrodynamic effects on a mooring line. While a commercial program can predict reasonable quasi-static responses, costly modeling is required. This motivated us to propose a new method for predicting quasi-static responses that minimizes the mechanical energy of the whole system based on basic geometric parameters, and that is easy to implement. In this study, the mechanical energy of moored floating structures is assumed to be the sum of gravitational–buoyancy potential energy, kinetic energy induced by drag forces, and spring potential energy derived by line tension. We introduce fundamental theoretical background for the development of the proposed method. We investigate the effect of quasi-static actions on mooring response, comparing the proposed method’s results with those from the catenary equation and ABAQUS software. The study reveals the shortcomings of the catenary equation in offshore applications. We also compare quasi-static responses derived by the AQWA numerical package with the results calculated from the proposed method for an 8 MW WindFloat 2 type of platform. Good agreement was drawn between the proposed method and AQWA. The proposed method proves more timesaving than AQWA in terms of modeling of mooring lines and floaters, and more accurate than the catenary equation, and can be used effectively in the early design phase of dimension mooring lengths for moored floating structures.

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Liang, Peng, Zhong Ping Qin, and Guo Xing Wang. "Behavior of Super Long Span Cable-Stayed Bridges during the Construction." Applied Mechanics and Materials 63-64 (June 2011): 474–77. http://dx.doi.org/10.4028/www.scientific.net/amm.63-64.474.

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In order to accurately reflect the effects and the spatial and temporal variation of long span cable-stayed bridge during the construction process, this paper, based on total CR formulation and the catenary cable element, improves the existing methods of geometrically nonlinear analysis and then develops a new software for nonlinear analysis of bridge through the entire construction.

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Li, Xinxia, Lan Tao, and Mingjie Liu. "Force Transfer Mechanism and Component-Based Model of Cast-Steel-Stiffened Circular-Tube-Column Frames for Progressive Collapse Analysis." Buildings 12, no. 7 (July 20, 2022): 1049. http://dx.doi.org/10.3390/buildings12071049.

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In this paper, the system response, stress redistribution, failure mode, and catenary effect of steel frames with circular tube columns and cast steel stiffener (CSS) joints under a sudden column removal scenario were revealed. Based on this force transfer mechanism analysis, a practical and computationally efficient component-based model considering catenary effects and CSS joint details with a series of springs was established and validated by a detailed solid-element method. By using this component-based model, the proper dynamic response increase factor of the CSS joint frames was investigated. The results show that the great overall stiffness and strength of the CSS limit the deformation of the column front shell. Therefore, the CSS joint frames have superior performance for progressive collapse prevention than the frames using welded joints without stiffeners. In addition, the component-based model is validated to be effective and the dynamic response increase factor of the frames with circular tube columns and CSS joints is smaller than 2.0.

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Bont, Leo Gallus, Laura Ramstein, Fritz Frutig, and Janine Schweier. "Validation of Catenary-based Methods for Cable Road Layout Planning." Environmental Sciences Proceedings 3, no. 1 (November 10, 2020): 102. http://dx.doi.org/10.3390/iecf2020-07775.

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Cable-based technologies have been a backbone for harvesting on steep slopes. Computing the layout of a single cable road requires considering the standards of structural design, aiming to (1) guarantee structural safety, and (2) provide the required serviceability. Currently applied analysis methods, such as the Pestal method, are unprecise. Alternatively, methods based on the catenary, such as Zweifel or Irvine, are better suited to analyze and predict load path and occurring forces for skylines anchored fix on both ends. However, studies that validate those catenary analyses (concurrently load path and forces) are rare and were not carried out under realistic heavy load conditions. Therefore, the aim of the project was to validate the catenary analyses under realistic, heavy load conditions for cable roads with multiple spans. In two case studies in Switzerland, the deflection in every span as well as the skyline tensile force at the anchor were measured for different load configurations and compared with theoretical computations of Zweifel and Pestal. The approach of Zweifel maps the mechanical properties realistic. However, as proven by our measurements, it slightly overestimated the deflection and the skyline tensile forces because the friction on the supports was neglected (between skyline and saddle). The deflections calculated with the Pestal formulas were significantly larger than the measured values, in particular with heavy load and in large spans. Our measurement studies confirmed that the mechanical properties of a cable road can be described adequately with the algorithm by Zweifel. However, it should be further developed with the inclusion of effects like the friction to improve the efficiency, safety and cost-performance ratio in cable road planning.

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He, Fan, Dandan Guo, and Liming Chen. "Numerical study of contact wire tension affecting dropper stress of a catenary system." Advances in Mechanical Engineering 13, no. 3 (March 2021): 168781402199504. http://dx.doi.org/10.1177/1687814021995041.

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Dropper is the key component of in a catenary system and it is prone to fatigue fracture. Dropper stress directly affects the operation safety of high-speed railway. In this paper, a span of dropper in a catenary system is modeled to investigate the effects of contact wire tension on dropper stress. The response equation of contact wire and the theoretical equation of dropper stress are deduced. The initial and boundary conditions of each dropper are determined, and then the stress of each dropper is calculated by the finite difference method using a MATLAB program. The results show that the stress amplitude and the maximum tensile stress of the dropper decrease significantly with the increase of contact wire tension. When the tension is low, the stress changes of dropper near the load location experience three stages: instant rebound, attenuated vibration, and bending compression. However, the attenuation vibration stage disappears when the tension is increased to a certain extent. Therefore, the control of the vibration response of the contact wire can effectively reduce the stress amplitude and the maximum tensile stress of the dropper, so as to improve the working reliability of the dropper.

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D’Archino, Roberta, and Giuseppe C. Zuccarello. "Two red macroalgae newly introduced into New Zealand: Pachymeniopsis lanceolata (K. Okamura) Y. Yamada ex S. Kawabata and Fushitsunagia catenata Filloramo et G. W. Saunders." Botanica Marina 64, no. 2 (March 31, 2021): 129–38. http://dx.doi.org/10.1515/bot-2021-0013.

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Abstract Introductions of macroalgae are becoming more common with increased surveillance and the use of molecular tools to unequivocally identify invaders. We here report two non-indigenous macroalgal species newly confirmed to be present in New Zealand. Pachymeniopsis lanceolata is an irregularly divided foliose blade, first detected in Lyttleton Harbour/Whakaraupō, South Island but here also reported from the North Island. It has known introductions from its native range in Pacific Asia to the Mediterranean, Atlantic and the eastern Pacific. The introduced cox3 haplotype was also found in New Zealand, suggesting a secondary introduction from a previous introduced area, but we also found a novel haplotype in the North Island suggesting a case of multiple introductions. Fushitsunagia catenata, a recent segregate from Lomentaria, was also first detected in Whakaraupō and was initially identified as a species of Champia. RbcL data shows that it belongs to F. catenata. This species is also of Asian origin and has been known to have been introduced to Spain, Mexico, and Australia. We provide morphological and reproductive descriptions of the species in New Zealand. Continued surveillance, and follow up monitoring, are needed to track the expansion and effects of these macroalgae on native biotas.

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Zhu, Jianbei, Mario M. Attard, and David C. Kellermann. "In-Plane Nonlinear Buckling of Funicular Arches." International Journal of Structural Stability and Dynamics 15, no. 05 (May 27, 2015): 1450073. http://dx.doi.org/10.1142/s0219455414500734.

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This paper presents a numerical technique to determine the full pre-buckling and post-buckling equilibrium path for elastic funicular arches. The formulation includes the effects of shear deformations and geometric nonlinearity due to large deformations. The Timoshenko beam hypothesis is adopted for incorporating shear. Finite strains are considered without approximation. The finite strains are defined in terms of the normal and shear component of the longitudinal stretch. The constitutive relations for the internal actions are based on a hyperelastic constitutive model. Using the differential equilibrium equations and the constitutive laws, the nonlinear buckling behavior of some typical funicular arches are investigated using the trapezoid method with Richardson extrapolation enhancement. The results are validated by using the finite element package ANSYS and solutions available in the literature. Examples include parabolic arches under a uniformly distributed gravity load, a catenary under a distributed load along the arch and a catenary arch under an overburden load. Parametric studies are performed to identify the factors that influence the nonlinear buckling of funicular arches. The axial to shear rigidity ratio is shown to have a significant effect on the buckling load and the buckling mode shape.

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Malan, Daniel E. "Predicted effects of a hypothetical oil spill on the saltmarsh crab Sesarma catenata." Oil and Chemical Pollution 6, no. 2 (January 1990): 137–59. http://dx.doi.org/10.1016/s0269-8579(05)80015-2.

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Lee, C. Y., C. H. Huang, H. E. Lin, J. Y. Lin, S. P. Yu, Y. L. Yang, and H. H. Huang. "Modelling on the synergy of mechanical and electrical wear in a current line/catenary-pantograph system." Journal of Physics: Conference Series 2345, no. 1 (September 1, 2022): 012001. http://dx.doi.org/10.1088/1742-6596/2345/1/012001.

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Abstract The metro system of electrified rolling stock is an important vehicle for partly solving the metropolitan transportation and carbon emission problems. This study aims to analyse the wear of current collector/catenary-pantograph system in the rolling stock. A theoretical wear rate model between the conductor wire and the current collector of the pantograph system was adopted from the literature and further decomposed into mechanical load, electrical current, current arc erosion, and the synergy components. Based on the decomposed model, an experimental protocol for finding the curve-fitted parameters for the theoretical model was proposed. The numerical data adopted from a previous literature was employed in the decomposed model to discuss the effects of mechanical loading, electrical current, and vehicle speed on the wear rate components. From the decomposed wear rate model, the so-called electrical current lubrication on the total wear rate due to the applied electrical current could be observed directly. Moreover, the nonlinear couplings among the control factors in the operation of the system manifested significantly. Thus, in the design phase the optimization analysis should be performed on the control parameters using the theoretical wear rate model to extend the life and reliability of this catenary-pantograph system.

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Webb, TH, and SJ Burgham. "Catenary relationships of downland soils derived from loess, South Canterbury, New Zealand." Soil Research 32, no. 1 (1994): 1. http://dx.doi.org/10.1071/sr9940001.

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Very limited information is available on soil variability within the large soil map units of the loess-mantled downlands of the east coast of South Island, New Zealand. In this study eight profiles were sampled in a catenary transect across a valley to assess the morphological, chemical and particle-size changes both within and between soil profiles for both sunny and shady aspects. Profiles from each landform element had similar sequences of horizons but thickness of horizons varied. Profiles on shoulder slopes had thinnest topsoil and subsoil horizons above underlying fragipans. There was a rapid thickening of topsoils and depth to fragipans immediately below the point of slope inflection between planar midslopes and concave lower slopes. The most striking difference in soil morphology was the overthickened topsoil horizons in footslope sites. This was attributed to effects of cultivation, either directly, through mechanical movement of soil material during cultivation operations, or indirectly, through the promotion of soil erosion. There was no indication of the expected catenary relationship involving translocation of exchangeable bases from upper to lower slopes. Differences in P-retention, KCl-extractable aluminium and clay content were identified in soils with different aspects but were not attributed to climatic differences.

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Ferraioli, Massimiliano. "Progressive Collapse Performance of Steel Beam-to-Column Connections: Critical Review of Experimental Results." Open Construction & Building Technology Journal 15, no. 1 (December 20, 2021): 152–63. http://dx.doi.org/10.2174/1874836802115010152.

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Background: The steel beam-to-column connections are vulnerable structural elements when a building loses one or more of its vertical load-carrying components due to abnormal or accidental loading conditions. After a column is destroyed by abnormal loads, the tensile axial force of the beam gradually increased, while the bending moment decreased, and the load-resistance mechanism shifts from a flexural mechanism to a catenary mechanism, with the axial force becoming the prevailing factor. Aims: This paper investigates the progressive collapse performance of steel beam-to-column connections. While undergoing large deformation, the beam-to-column connections are subjected to moment, shear, and tension in conjunction with high ductility demand. Their behavior under monotonic loading depends on the moment-axial tension interaction and greatly affects the progressive collapse resistance of the structure. This paper presents a critical review of experimental tests of different types of steel beam-column joints (flexible, rigid, and semi-rigid) under a central-column-removal scenario. Methods: The experimental results, including load-deformation relationships, failure modes, and catenary effects, are described in detail. The findings are used to evaluate the rotation capacity of different types of steel beam-to-column connections. The results are compared to the acceptance criteria specified by the main progressive collapse guidelines for several beam-to-column connection categories. Results: In simple (flexible) joints, the stiffness and strength at higher drift angles essentially depend on the tensile capacity of the connection that prevents, in some cases, the full development of the catenary mechanism. The connection depth alone does not seem to be an effective parameter to predict the rotational capacity of beam-to-column connections, since different connections with similar values of the connection depth result in very different values of the maximum rotation capacity. In fully rigid and semi-rigid connections, after the column removal, the flexural resistance controls the behavior at the preliminary phase, and the tensile force is almost zero. With increased downward displacement, the axial tensile force also increases, developing a catenary mechanism. Although the stiffness of rigid and semi-rigid connections is higher than flexible connections, both categories result in similar rotation capacity. Conclusion: In all the simple connections herein considered, the plastic rotation capacity obtained by tests was found much higher than the code recommended values that are probably too conservative. On the contrary, for one rigid and two semi-rigid connections, the values of the plastic rotation capacity obtained by tests are lower than the corresponding recommended values. Thus, the suggested acceptance criteria proved to be out of the conservative side.

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Bai, Xinglan, Weiping Huang, Murilo Augusto Vaz, Chaofan Yang, and Menglan Duan. "Riser-soil interaction model effects on the dynamic behavior of a steel catenary riser." Marine Structures 41 (April 2015): 53–76. http://dx.doi.org/10.1016/j.marstruc.2014.12.003.

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Li, Ling, Wei Wang, Lip H. Teh, and Yiyi Chen. "Effects of span-to-depth ratios on moment connection damage evolution under catenary action." Journal of Constructional Steel Research 139 (December 2017): 18–29. http://dx.doi.org/10.1016/j.jcsr.2017.09.011.

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32

Zárate, Boris Adolfo, and Juan Martin Caicedo. "Effects of Cable Dynamics in the Modeling of Cable-Stayed Bridges Under Seismic Excitation." International Journal of Structural Stability and Dynamics 15, no. 04 (May 2015): 1450061. http://dx.doi.org/10.1142/s0219455414500618.

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New longer and bigger cable-stayed bridges are planned for the future, increasing the necessity of improving the way bridge models are used, especially when the models are used for dynamic behavior. This paper studies how the dynamic behavior of the deck and towers of a particular structure are affected when the cables are modeled with three different cable models. A finite element model of the Bill Emerson Memorial Bridge is used to compare the different methodologies. Three cable models are used in this study including the equivalent Young's modulus, the elastic catenary and the elastic isoparametric formulation. Results show that in the case of the Bill Emerson Memorial Bridge the tower behaves differently depending on the cable model used while the deck has a similar behavior independent on the cable model used.

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Tartaglia, Roberto, and Alessia Campiche. "Influence of the Bolt Material Properties on the Ultimate Capacity of End Plate Bolted Joint Subjected to Column Loss." Key Engineering Materials 885 (May 2021): 133–39. http://dx.doi.org/10.4028/www.scientific.net/kem.885.133.

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This paper investigates the performance of extended stiffened end-plate bolted beam-to-column joints subjected a column loss scenario by means of finite element simulations. An advanced numerical model was developed, and its effectiveness was validated against the experimental results. The influence of the bolt strengthening on the column loss action was investigated changing the grade of bolts. The results showed that the joint performance under column loss scenario are deeply related to the development of the catenary action that depends from the connection ductility; therefore increasing the bolt material strength will provide beneficial effects on the joint capacity under the column loss.

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34

Feng, Aichun, Hooi Siang Kang, Binbin Zhao, and Zhiyu Jiang. "Two-Dimensional Numerical Modelling of a Moored Floating Body under Sloping Seabed Conditions." Journal of Marine Science and Engineering 8, no. 6 (May 28, 2020): 389. http://dx.doi.org/10.3390/jmse8060389.

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A coupled floating body-mooring line model is developed by combining a boundary element model for a two-dimensional floating body and a catenary mooring line model. The boundary element model is formulated in the time domain by a continuous Rankine source, and a reflection potential is introduced to account for the wave reflection due to sloping seabed. This newly developed model is validated by comparisons against available data. Then, dynamic response analyses are performed for the moored body in various seabed conditions. Compared with a flat seabed, a sloping seabed causes unsymmetrical mooring line configuration and generates noticeable effects in the motion responses of the floating body.

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35

Yang, N., D.-S. Jeng, and X. L. Zhou. "Tension Analysis of Submarine Cables during Laying Operations." Open Civil Engineering Journal 7, no. 1 (December 27, 2013): 282–91. http://dx.doi.org/10.2174/1874149520131130009.

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This paper presents a semi-analytical approximation for a two-dimensional (2D) tension analysis of submarine cables during laying operations. In the analysis, based on geometric compatibility relations and equilibrium equations, a set of non-linear differential equations are obtained. The present model considers effects of ocean currents, cable ship motion, pay-out rate, water depth and material properties on submarine cable behavior in water, which are crucial during laying operations. As shown in numerical examples, with consideration of currents and cable ship motion, the cable tension appears to be smaller and cable configuration curve tends to be fatter than the conventional catenary theory.

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36

McCullough, M. K., and E. J. Haug. "Dynamics of High Mobility Track Vehicles." Journal of Mechanisms, Transmissions, and Automation in Design 108, no. 2 (June 1, 1986): 189–96. http://dx.doi.org/10.1115/1.3260801.

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A mechanical system superelement that represents spatial dynamics of high mobility track vehicle suspension systems is derived. Using results from a companion paper [1], the equations of motion for a suspension system with an arbitrary number of road wheels are systematically derived. Track is represented as a complex internal force element that acts between ground, wheels, and the chassis of the vehicle. Track tension is computed from a relaxed catenary relationship and track bridging effects are modeled. Numerical results for driver acceleration and absorbed power, as well as track tension are presented. A factor of 90 decrease in compute time is achieved over a comparable multibody model of the same vehicle.

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Abbasi, M. Z., B. Noor, M. A. Aman, S. Farooqi, and F. W. Karam. "An Investigation of Temperature and Wind Impact on ACSR Transmission Line Sag and Tension." Engineering, Technology & Applied Science Research 8, no. 3 (June 19, 2018): 3009–12. http://dx.doi.org/10.48084/etasr.2046.

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Power transmission is mainly based on overhead transmission lines with conductors being supported by transmission towers. Transmission lines are subjected to environmental stress (temperature changes, winds, snow etc), have an impact on the surrounding areas (visual pollution, building restrictions) and experience heavy losses due to resistive, magnetic and capacitive effects. Thus, proper modeling and installation of these conductors are necessary. The conductors are generally installed in a catenary shape to minimize the capacitive effects and to balance the tension. This paper presents an investigation on the sag and tension behavior under different temperature and wind of ACSR (Aluminum Conductor-Steel Reinforced) lines. Four different cases of temperature and wind are tested to calculate sag and tension. Simulation setup is done in ETAP (electrical transient and analysis program). Results are recorded and discussed.

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38

Song, Yang, Tengjiao Jiang, Anders Ronnquist, Petter Navik, and Gunnstein Froseth. "The Effects of Spatially Distributed Damping on the Contact Force in Railway Pantograph-Catenary Interactions." IEEE Transactions on Instrumentation and Measurement 70 (2021): 1–10. http://dx.doi.org/10.1109/tim.2021.3091459.

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39

Chen, Haifei, Sipeng Xu, and Haiyan Guo. "Nonlinear analysis of flexible and steel catenary risers with internal flow and seabed interaction effects." Journal of Marine Science and Application 10, no. 2 (June 2011): 156–62. http://dx.doi.org/10.1007/s11804-011-1055-4.

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40

Li, Ruiping, Weihua Zhang, Zhou Ning, Binbin Liu, Dong Zou, and Wei Liu. "Influence of a high-speed train passing through a tunnel on pantograph aerodynamics and pantograph–catenary interaction." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 231, no. 2 (August 4, 2016): 198–210. http://dx.doi.org/10.1177/0954409715626743.

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Aerodynamics of trains running inside tunnels change more significantly in comparison with open air scenarios. It has been confirmed that the lateral vibration as well as the aerodynamic drag of the trains is increased and the micro-pressure wave is produced at the tunnel exit when the trains are passing through tunnels. The aim of this article is to explore the impact of a high-speed train passing through a tunnel on the pantograph aerodynamics and the dynamic behavior of the pantograph–catenary interaction. The aerodynamic forces acting on the pantograph are investigated thoroughly by extensive numerical simulations as well as systematic field tests. To investigate the effects of the aerodynamic forces of pantograph on the quality of current collection, the numerical simulations of the pantograph–catenary dynamic interaction are conducted with our proposed model, taking into consideration the action of the aerodynamic uplift forces obtained by the numerical simulations on the pantograph. Then, a series of numerical simulations are also carried out to analyze the effects of the train speed and the blockage ratio on the aerodynamic uplift forces of the pantograph, on the contact forces, as well as on the displacement of the contact wire, while the train is passing through a tunnel. The results reveal that compared with the open air scenarios, the aerodynamic drag and uplift forces of the pantograph, the mean value of the contact force and the displacement level of the registration arm can considerably increase as the train runs inside a tunnel. Moreover, the statistical values of the contact forces and the displacement level of the contact wire become larger while the train is passing through the tunnel at different speeds. On the other hand, the quality of current collection decreases with the increasing of the blockage ratio.

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41

Jing, Tian Hu, and Qing Ning Li. "Effects Analysis of Bending Stiffness of Cables on Stress Distribution and Curve Shape in Super-Long Single Suspension Cable Structures." Advanced Materials Research 163-167 (December 2010): 173–76. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.173.

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The design scheme of a suspension bridge with a super-long-span of 3300 m was taken as an example, and calculating results from 3 mechanics models are compared with each other to study the effects of bending stiffness of cables on stress distribution and curve shape in super-long single suspension cable structures on the basis of the Finite Element Method (FEM) algorithm of ANSYS and the analytical segmental catenary method for cables’ shape-finding. The study shows that the influence of bending stiffness on curve shape-finding of cables is negligible; Although its effects on stress distribution in cross sections of main cables due to dead loads is small, the error of horizontal forces probably results in great one for the calculation of bending moments at the bottom cross-sections of bridge pylons, which needs attention to ensure the structural safety.

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42

Bright, Diane, Fahiem El-Borai, Robin Stuart, James Graham, Jaime Cubero, and Larry Duncan. "Differential susceptibility of entomopathogenic nematodes to nematophagous fungi from Florida citrus orchards." Nematology 11, no. 2 (2009): 231–41. http://dx.doi.org/10.1163/156854109x429565.

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AbstractLaboratory experiments were conducted to study the effects of various trapping and endoparasitic nematophagous fungi (NF) isolated from Florida citrus orchards on five entomopathogenic nematode (EPN) species that show various distributions across Florida's citrus industry. Four trapping NF (Arthrobotrys oligospora, A. dactyloides, A. musiformis and Gamsylella gephyropaga) and two endoparasitic NF (Catenaria sp. and Myzocytium sp.) were tested against Steinernema diaprepesi (Sd), S. glaseri (Sg), S. riobrave (Sr), Heterorhabditis zealandica (Hz) and H. indica (Hi). Fungi were added to soil microcosms either as a pure culture on agar plugs (trapping NF) or as fungal-colonised nematodes (endoparasitic NF) on agar plugs, concurrently with 2000 EPN of a given species. After 7 or 14 days exposure, nematodes were recovered from the soil using Baermann funnels. The recovery of all EPN species was reduced between 56-92% by G. gephyropaga. Neither Sd or Sg were affected by any species of Arthrobotrys, whereas A. musiformis reduced recovery of all other EPN and A. oligospora reduced numbers of all other species except Hi. Both endoparasitic NF reduced the recovery of all EPN except Hi by at least 82%. The data are consistent with the hypothesis that NF may play a role in regulating regional patterns of abundance and diversity of EPN species in Florida, which in turn regulate the abundance of a major citrus pest, the Diaprepes root weevil, Diaprepes abbreviatus.

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Su, Yu, Yuanying Qiu, and Peng Liu. "Optimal Cable Tension Distribution of the High-Speed Redundant Driven Camera Robots Considering Cable Sag and Inertia Effects." Advances in Mechanical Engineering 6 (January 1, 2014): 729020. http://dx.doi.org/10.1155/2014/729020.

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Camera robots are high-speed redundantly cable-driven parallel manipulators that realize the aerial panoramic photographing. When long-span cables and high maneuverability are involved, the effects of cable sags and inertias on the dynamics must be carefully dealt with. This paper is devoted to the optimal cable tension distribution (OCTD for short) of the camera robots. Firstly, each fast varying-length cable is discretized into some nodes for computing the cable inertias. Secondly, the dynamic equation integrated with the cable inertias is set up regarding the large-span cables as catenaries. Thirdly, an iterative optimization algorithm is introduced for the cable tension distribution by using the dynamic equation and sag-to-span ratios as constraint conditions. Finally, numerical examples are presented to demonstrate the effects of cable sags and inertias on determining tensions. The results justify the convergence and effectiveness of the algorithm. In addition, the results show that it is necessary to take the cable sags and inertias into consideration for the large-span manipulators.

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YANG, Y. B., and JIUNN-YIN TSAY. "TWO-NODE CATENARY CABLE ELEMENT WITH RIGID-END EFFECT AND CABLE SHAPE ANALYSIS." International Journal of Structural Stability and Dynamics 11, no. 03 (June 2011): 563–80. http://dx.doi.org/10.1142/s021945541100421x.

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The effect of rigid ends is considered in the formulation of a general two-node cable element for the analysis of cable-supported structures. The stiffness matrix of the catenary cable element was derived as the inverse of the flexibility matrix, with allowances for self-weight and pretension effects. In modeling the cables of suspension bridge, distinction is made between single cables (e.g., stay cables and hangers) and multi segment cables (e.g., main cables). The unstressed length of each cable element in terms of the pretension force is determined by a trial-and-error procedure prior to structural analysis. Cable shape analysis was conducted to determine the configuration of main cables for cable-supported bridges under the dead loads. It was demonstrated that the effect of rigid ends cannot be ignored for taut cables, that is, cables with large pretensions. Further, the cable element derived can be reliably used in the analysis of cable-supported bridges, regardless of the sag magnitudes.

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45

Collina, A., F. Fossati, M. Papi, and F. Resta. "Impact of overhead line irregularity on current collection and diagnostics based on the measurement of pantograph dynamics." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 221, no. 4 (July 1, 2007): 547–59. http://dx.doi.org/10.1243/09544097f02105.

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As train speed increases, contact wire irregularity affects the quality of current collection more and more. The possibility of achieving the maximum operating speed depends also on the maintenance level of the overhead line (OHL). In the present paper, the influence of contact wire irregularity (in terms of vertical deviation of its position) is investigated both experimentally and by means of numerical simulation of the dynamic interaction of pantograph and catenary. In a first step, the capability of the simulation to reproduce the effect of a singularity in the contact wire height along the line has been tested by comparison with available experimental results. The same model has been subsequently used to perform numerical experiments concerning the effects of several types of distributed defects on the catenary. Afterwards, considering the data generated with the simulation as experimental data, a procedure to find the signature in terms of the contact force of the considered distributed defects on the OHL has been proposed. In this procedure, the contact force is not measured, but estimated from the motion of the pantograph, by means of an application of the extended Kalman filter. The adoption of an estimation procedure for the contact force, instead of a direct measurement, would allow the installation of a measurement system that is much simpler than the one required for the direct measurement of contact force. For this feature, it could be installed, at least in principle, on ordinary trains, allowing to perform an extensive monitoring and diagnostic activity with a large database.

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Behroozi, F., P. Mohazzabi, and J. McCrickard. "Unusual shapes for a catenary under the effects of surface tension and gravity: A variational treatment." Physical Review E 51, no. 2 (February 1, 1995): 1594–97. http://dx.doi.org/10.1103/physreve.51.1594.

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47

Ferraioli, Massimiliano, Angelo Lavino, Alberto Mandara, Marianna Donciglio, and Antonio Formisano. "Seismic and Robustness Design of Steel Frame Buildings." Key Engineering Materials 763 (February 2018): 116–23. http://dx.doi.org/10.4028/www.scientific.net/kem.763.116.

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In this paper, a design procedure that combines both progressive collapse design under column removal scenario and capacity design to produce a hierarchy of design strengths is presented. The procedure develops in the context of the European Standards, using the classification of European steel sections and considering the seismic design features. Three-dimensional models of typical multi-storey steel frame buildings are employed in numerical analysis. The design for progressive collapse is carried out with three types of analysis, namely linear static, nonlinear static and nonlinear dynamic. Since the behaviour following sudden column loss is likely to be inelastic and possibly implicate catenary effects, both geometric and material nonlinearities are considered. The influence of the fundamental parameters involved in seismic and robustness design is finally investigated.

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He, Fan, and Dandan Guo. "The Effects of Load Location on Dropper Stress in a Catenary System for a High-Speed Railway." Mathematical Problems in Engineering 2020 (October 8, 2020): 1–10. http://dx.doi.org/10.1155/2020/7986141.

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In this paper, the effects of load location on dropper stress are studied. We treat contact wire as a beam element and derive its response equation and then deduce the stress equation of dropper. A computer code based on MATLAB is written to calculate dropper stress using the finite difference method. The results show that there are three stages during the period of the stress changes of dropper, including instant rebound, damped sinusoidal vibration, and bending compression. The shorter the distance away from a load is, the larger the vertical displacement of the dropper is, which results in the corresponding increases of its stress amplitude and the maximum tensile stress. The load location has a significant impact on the stress changes of dropper. Compared to the condition of the load in the middle, the load acting on the edge of contact wire could induce the larger tensile stress when both ends of contact wire are considered as free boundaries. Therefore, it is necessary to add supports at both ends.

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Lim, Namyo Salim, K. H. Tan, and C. K. Lee. "Effects of rotational capacity and horizontal restraint on development of catenary action in 2-D RC frames." Engineering Structures 153 (December 2017): 613–27. http://dx.doi.org/10.1016/j.engstruct.2017.09.059.

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50

Guo, Lan Hui, Shan Gao, and Su Mei Zhang. "Behavior of Rigid Composite Joint under Combination of Bending Moment and Tensional Force." Advanced Materials Research 163-167 (December 2010): 2247–55. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.2247.

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In recent years, the progressive collapse of buildings increases the interest in progressive collapse studies. If a key column fails in structure, the internal force is redistributed by the catenary action of joint to prevent its progressive collapse. The joint connecting to the failed column is under the state of bending moment combined with tensional force and the tensional force would affect the moment-resistance ability and ductility of joint. In this paper, the finite element software ABAQUS is applied to analyze the behavior of composite joints under the state of bending moment combined with tensional force. The effects of rebar ratio, rebar strength, concrete strength, etc., on the behavior of joints are investigated. The results show that high strength steel is suggested to be used in composite joint to improve its bending moment capacity and tensional capacity.

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Journal articles on the topic 'Effetto catenaria'

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