期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
Seismic performance of a reinforced concrete building retrofitted with self-centering shape memory alloy braces 被引量:2
1
作者 Massimiliano Ferraioli Antonio Concilio Carmine Molitierno 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第3期785-809,共25页
Self-centering earthquake-resistant structures have received increased attention due to their ability to reduce post-earthquake residual deformations and,thus,repair time and cost.This stimulated the development of re... Self-centering earthquake-resistant structures have received increased attention due to their ability to reduce post-earthquake residual deformations and,thus,repair time and cost.This stimulated the development of recentering shape memory alloy(SMA)dampers that use superelastic nitinol wires to dissipate energy and self-center the structure.However,there are still a few case studies applications on full-scale RC buildings in the literature.Moreover,general guidelines or even simplified approaches for the practical design of SMA damped braces are still lacking.This paper focuses on evaluating the effect of using self-centering shape memory alloy dampers for buckling-restrained braces applied for the seismic retrofit of a complex RC building structure.A design method originally proposed for elastoplastic dampers was implemented to size the SMA dampers to be placed on selected spans and stories of a building.The effectiveness of the design procedure was demonstrated by nonlinear time-history analyses under different sets of earthquake strong ground motions.The analysis results show that the recentering shape memory alloy bracing system is effective in limiting the maximum transient inter-story drifts and reducing the residual inter-story drifts after strong seismic events,due to its excellent recentering behavior together with its not negligible energy dissipation capacity. 展开更多
关键词 RC buildings seismic retrofit buckling-restrained braces shape memory alloys dampers SELF-CENTERING
下载PDF
Monitoring and Identification of the Seismically Isolated “Our Lady of Tears” Shrine in Syracuse
2
作者 Daniele Losanno Mariacristina Spizzuoco 《Open Journal of Civil Engineering》 2018年第4期373-410,共38页
This paper describes the installation and management of the monitoring system of the “Our Lady of Tears Shrine” in Syracuse, whose dome is an imposing r.c. and prestressed r.c. structure of about 22,000 ton that was... This paper describes the installation and management of the monitoring system of the “Our Lady of Tears Shrine” in Syracuse, whose dome is an imposing r.c. and prestressed r.c. structure of about 22,000 ton that was seismically isolated by flat sliding devices with hysteretic dampers. The monitoring system, representing an upgrading and improvement of an old system never made working, has some innovative features, because it allows to manage with the same dedicated hardware and software both the slow (thermal variations, relative humidity, wind direction and velocity) and the fast acquisitions (dynamic vibrations by wind and earthquake). The monitoring system was inserted among those structures maintained and controlled by the Seismic Observatory of Structures of the National Department of Civil Protection. Some records of low magnitude earthquakes allowed to validate the correct behaviour of the whole structure, as well as to make a dynamic identification of the complex construction and to calibrate a detailed finite element model of the Sanctuary, thus predicting isolators’ behaviour under design earthquake. 展开更多
关键词 SEISMIC Isolation Structural Health MONITORING Dynamic IDENTIFICATION FEM Model Non Linear Analysis
下载PDF
Influence of earthquake direction on the seismic response of irregular plan RC frame buildings 被引量:3
3
作者 Magliulo G Maddaloni G Petrone C 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第2期243-256,共14页
The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismi... The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismic response of building structures is examined. Three multi-story RC buildings, representing a very common structural typology in Italy, are used as case studies for the evaluation. They are, respectively, a rectangular plan shape, an L plan shape and a rectangular plan shape with courtyard buildings. Nonlinear static and dynamic analyses are performed by considering different seismic levels, characterized by peak ground acceleration on stiff soil equal to 0.35 g, 0.25 g and 0.15 g. Nonlinear dynamic analyses are carried out by considering twelve different earthquake directions, and rotating the direction of both the orthogonal components by 30° for each analysis(from 0° to 330°). The survey is carried out on the L plan shape structure. The results show that the angle of the seismic input motion signifi cantly infl uences the response of RC structures; the critical seismic angle, i.e., the incidence angle that produces the maximum demand, provides an increase of up to 37% in terms of both roof displacements and plastic hinge rotations. 展开更多
关键词 plan irregularity nonlinear analyses reinforced concrete buildings seismic performance ground motion directionality
下载PDF
New Trends in Nano-Engineering
4
作者 HRaffaele Barretta 《Chemical Reports》 2019年第1期1-2,共2页
With rapid developments of nanoengineering in the recent years, highperformance and multi-functional nanomaterials, exhibiting new and enhanced physical and chemical properties, are introduced with innumerable conceiv... With rapid developments of nanoengineering in the recent years, highperformance and multi-functional nanomaterials, exhibiting new and enhanced physical and chemical properties, are introduced with innumerable conceivable applications. The recent advances in design, synthesis and characterization techniques of nano-materials have enabled the fabrication of modern nano-electromechanical systems (NEMS). 展开更多
关键词 NEW TRENDS Nano-Engineering RAPID DEVELOPMENTS
下载PDF
The dynamics of river confluences and their effects on the ecology of aquatic environment:A review 被引量:3
5
作者 Sai-yu Yuan Lei Xu +2 位作者 Hong-wu Tang Yang Xiao Carlo Gualtieri 《Journal of Hydrodynamics》 SCIE EI CSCD 2022年第1期1-14,共14页
Confluences act as critical nodes in a river system.They affect hydrodynamics,sediment transport,bed morphology,and eco-hydraulics of the river system.Convergence of streams produces the complex mechanism of flow mome... Confluences act as critical nodes in a river system.They affect hydrodynamics,sediment transport,bed morphology,and eco-hydraulics of the river system.Convergence of streams produces the complex mechanism of flow momentum and mass mixing which may affect the aquatic environment locally and even lasting for a long distance downstream.The confluence creates a hotspot for the river system’s ecological change,which usually leads to changes in water temperature,suspended-sediment load,bed material,nutrient concentrations,water chemistry,and organic-matter content.Hence,the dynamics of river confluences are very complex and have critical effects on river system’s water environment and ecology.For this reason,a review summarizing turbulent flow,sediment transport,morphological-dynamics,mixing processes,and their effects on the ecology of the aquatic environment at river confluences is in order.A future research agenda and opportunities pertinent to river confluence are vitally emphasized as a multidisciplinary research topic. 展开更多
关键词 River confluence hydrodynamics sediment transport morpho dynamics water environment water ecology
原文传递
Performance analysis of a floating photovoltaic covering system in an Indian reservoir 被引量:2
6
作者 Nagananthini Ravichandran Nagavinothini Ravichandran Balamurugan Panneerselvam 《Clean Energy》 EI 2021年第2期208-228,共21页
Floating photovoltaic(FPV)systems are one of the globally emerging technologies of renewable energy production that tend to balance the water-energy demand by effectively saving the evaporated water from reservoirs wh... Floating photovoltaic(FPV)systems are one of the globally emerging technologies of renewable energy production that tend to balance the water-energy demand by effectively saving the evaporated water from reservoirs while generating electrical power.This study presents the performance analysis of a model FPV plant in an Indian reservoir.The Mettur dam reservoir located in Tamil Nadu,India with a hydroelectric power plant of 150-MW capacity is considered as a test case.The preliminary design of the FPV plant is proposed based on a detailed study of the key design elements and their suitability for Indian reservoirs.The proposed plant is numerically analysed for various tilt angles,mounting systems and tracking mechanisms in order to assess its potential power generation.A flat-mount system in landscape orientation was found to exhibit a high performance ratio.Further,a fixed-tilt FPV system with a panel slope of 10°and an FPV system with single-axis tracking were found to be suitable for the Mettur reservoir.Further,cost analysis of the FPV system is also presented along with the carbon-footprint estimation to establish the economic and environmental benefits of the system.The results show that the total potential CO_(2) saving by a FPV system with tracking is 135918.87 t CO_(2) and it is 12.5%higher than that of a fixed-mount FPV system. 展开更多
关键词 solar energy floating photovoltaic system evaporation loss hydroelectric power plants
原文传递
Nonlinear dynamics of a wind turbine tower 被引量:1
7
作者 A.GESUALDO A.IANNUZZO +1 位作者 F.PENTA M.MONACO 《Frontiers of Mechanical Engineering》 SCIE CSCD 2019年第3期342-350,共9页
The recent proliferation of wind turbines has revealed problems in their vulnerability under different site conditions, as evidenced by recent collapses of wind towers after severe actions. Analyses of structures subj... The recent proliferation of wind turbines has revealed problems in their vulnerability under different site conditions, as evidenced by recent collapses of wind towers after severe actions. Analyses of structures subjected to variable actions can be conducted through several methods with different accuracy levels. Nonlinear dynamics is the most reliable among such methods. This study develops a numerical procedure to obtain approximate solutions for rigid-plastic responses of structures subjected to base harmonic pulses. The procedure's model is applied to a wind turbine tower subjected to inertial forces generated by harmonic ground acceleration, and failure is assumed to depend on the formation of shear hinges. The proposed approach provides an efficient representation of the post-elastic behavior of the structure, has a low computational cost and high effectiveness, and uses a limited number of mechanical parameters. 展开更多
关键词 nonlinear dynamics PLASTIC SHEAR FAILURE MODAL APPROXIMATION time HISTORY
原文传递
Lyapunov stability of competitive cells dynamics in tumor mechanobiology
8
作者 Angelo Rosario Carotenuto Arsenio Cutolo +1 位作者 Stefania Palumbo Massimiliano Fraldi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2021年第2期244-263,共20页
Poromechanics plays a key role in modelling hard and soft tissue behaviours,by providing a thermodynamic framework in which chemo-mechanical mutual interactions among fluid and solid constituents can be consistently r... Poromechanics plays a key role in modelling hard and soft tissue behaviours,by providing a thermodynamic framework in which chemo-mechanical mutual interactions among fluid and solid constituents can be consistently rooted,at different scale levels.In this context,how different biological species(including cells,extra-cellular components and chemical metabolites)interplay within complex environments is studied for characterizing the mechanobiology of tumor growth,governed by intra-tumoral residual stresses that initiate mechanotransductive processes deregulating normal tissue homeostasis and leading to tissue remodelling.Despite the coupling between tumor poroelasticity and interspecific competitive dynamics has recently highlighted how microscopic cells and environment interactions influence growth-associated stresses and tumor pathophysiology,the nonlinear interlacing among biochemical factors and mechanics somehow hindered the possibility of gaining qualitative insights into cells dynamics.Motivated by this,in the present work we recover the linear poroelasticity in order to benefit of a reduced complexity,so first deriving the well-known Lyapunov stability criterion from the thermodynamic dissipation principle and then analysing the stability of the mechanical competition among cells fighting for common space and resources during cancer growth and invasion.At the end,the linear poroelastic model enriched by interspecific dynamics is also exploited to show how growth anisotropy can alter the stress field in spherical tumor masses,by thus indirectly affecting cell mechano-sensing. 展开更多
关键词 Tumor growth Poroelasticity Cells competition Volterra-Lotka dynamics Stability
原文传递
基于中空单元的夹层平板结构设计方法研究(英文)
9
作者 Gianpaolo PERRELLA Giovanni Maria MONTUORI +1 位作者 Massimiliano FRALDI Elena MELE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第6期427-442,共16页
目的:大型的桁架结构或空间刚架结构可以认为是用中空单元组合而成的宏观结构,在结构初步设计时,如何设计排布中空基本单元以满足结构的性能要求是设计的关键。本文旨在探讨夹层平板结构,在给定竖向变形控制指标后,如何使用简化的方法... 目的:大型的桁架结构或空间刚架结构可以认为是用中空单元组合而成的宏观结构,在结构初步设计时,如何设计排布中空基本单元以满足结构的性能要求是设计的关键。本文旨在探讨夹层平板结构,在给定竖向变形控制指标后,如何使用简化的方法快速设计各层中空基本单元的尺寸和空隙程度。创新点:1.对于水立方这种复杂的空间多面体网格结构,本文将其理想化为连续的中空介质,利用微观力学中的均质化分析方法,将结构分解为多个基本单元(RVE)进行分析,从而推导出结构性能指标与单元参数之间的关系。2.对于大跨度平板结构,本文提出一种基于RVE重复叠加组合的设计方法,并利用有限元法对该方法进行检验。方法:1.对夹层平板结构的弯曲特性进行理论分析,根据Kirchhoff-Love理论,得到板弯曲刚度与各层的截面惯性矩之间的关系;2.通过理论推导出结构弯曲刚度(图3)、材料使用量(图4)随层厚度和层密度的变化关系;3.从基本单元出发,利用均质化分析方法分别对中空立方体(图5)和空间桁架结构(图6)进行分析,得到结构抗弯刚度随单元中空程度和距截面中性轴距离的函数关系(图7和8),进而推导出结构参数化设计的拟合公式;4.利用该设计公式,针对一个90 m×90 m×2.5 m的平板结构,以跨中挠度为跨度的1/500为设计指标,分别设计由两种基本单元组成的夹层平板结构,并将结构挠度的有限元计算结果与设计指标进行比较(图12)。结论:1.本文提出的利用中空单元组成的夹层平板结构的设计方法,通过优化设计中空单元的各项参数,可以在保证性能指标的同时最大化降低结构质量,得到最优刚度质量比。2.本设计方法和有限元法得到的结果之间差异非常小,说明该设计方法准确可靠。 展开更多
关键词 薄板 多层板 中空材料 均质化分析方法 刚度设计
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部