基于结构能量分析的抗震设计新方法的研究

概要介绍了多自由度结构能量分析方法，根据单自由度体系得到的输入能量谱，研究分析了多自由度与单自由度输入能量和耗能的等效性问题，并对一座钢筋混凝土框架结构算例进行了能量计算，对计算结果进行了分析，为能量分析设计方法应用于结构抗震设计进行有益的探索。     

变分法在结构抗震验算中的应用

本文介绍了利用变分原理推导的拟势能原理和拟余能原理，把拟势能原理和拟余能原理应用到结构抗震分析中，从而对结构受地震惯性力大小的范围问题进行研究，可以看出拟势能原理和拟余能原理可分别求解结构竖向地震压力的近似上、下限值。     

耗能减振结构的抗震设计方法

本文基于国内外耗能减振装置的性能试验和耗能减振结构的计算研究并结合我国正在修订的建筑结构抗震规范。提出了耗能减震结构抗震设计的统一方法。首先,提出了速度相关型线性耗能器和滞变型耗能器等效阻尼和刚度的计算方法;其次,通过大量的计算比较,研究了耗能减振结构非交阻尼阵强行解耦的精度和实际应用的可行性,提出了在结构地震反应分析了振型分解反应谱法中耗能器可统一归结为结构附加振型阻尼比的方法;第三,通过耗能减     

结构地震临界荷载的上、下限问题研究

本文介绍了利用变分原理推导的拟势能原理和拟余能原理，把拟势能原理和拟余能原理应用到结构地震临界荷载分析中，从而提出了一种计算结构地震临界荷载的新方法，同时从理论上论述了为什么利用拟势能原理和拟余能原理可以分析结构地震临界荷载的上、下限问题．     

Earthquake‐resistant structural design through energy demand and capacity

An energy‐based earthquake‐resistant structural design method is proposed. The proposed method uses specific input energy spectra, modal or time‐history analyses, and energy distribution among structural members. For a given member strength and stiffness, a relationship between the energy attributable to damage absorbed by a member and its cumulative ductility demand can be determined. Member strength, stiffness and energy capacity are design parameters which are simultaneously used in the design. The method can avoid soft‐storey design. The damage is measured based on a cumulative basis considering earthquake magnitude, frequency, and duration. Tests have been carried out to determine energy absorbing capacities of various structural components. More efforts are needed to make the energy‐based earthquake‐resistant structural design practical, but ssimple formulations for this method are possible. Copyright © 2007 John Wiley & Sons, Ltd.     

2010年4月14日青海玉树7.1级地震序列中小地震辐射能量的估计

本文利用震后架设的4个流动台站和震源区周围3个固定台站记录到的青海玉树7.1级地震序列波形资料,资料时间截止到2010年5月19日.经过传播路径效应和场地响应校正后,估算了玉树地震序列中80个中小地震的辐射能量.比较了辐射能量估计中不同方法之间结果存在的差异性,首次考虑了由于仪器频带宽度的限制而造成的中小地震辐射能量的低估与补偿问题,得到以下主要结论:(1)分别采用Andrews方法、震源实际谱方法(区分能量补偿前和后二种情况)和根据理论模型并将积分上限外推到所计算地震拐角频率的10倍的方法(理论谱方法)计算出的中小地震辐射能量4种结果基本上位于同一个量级水平之上,表明结果具有一定的可靠性和稳定性.这其中,Andrews方法得到的辐射能量最低,理论谱方法得到的结果最高,而由实际谱方法得到的地震辐射能量介于两者之间.(2)由古登堡经验公式得到的地震辐射能量远高于上述4种方法计算出的结果,能够达到理论谱方法结果的4倍,而且随震级的增大,由它带来的辐射能量的高估趋势更加明显.(3)由于没有考虑地震能量的补偿,Andrews方法得到的地震辐射量明显偏低.用两种不同方法进行地震辐射能量补偿后得到的结果比较接近,但考虑到仪器频带上限值设定的复杂性,认为由理论谱方法计算中小地震的辐射能量更加合适.(4)经过能量补偿后地震辐射能量要高于未作能量补偿的结果,能量补偿带来的辐射能量增加的作用对于小地震更加明显.在本文研究范围之内,不同方法得到的折合能量均明显存在随地震矩的增大而增大的现象,反映出玉树余震序列中大震地震辐射效率高于小震.     

配置自复位耗能跨低多层钢框架体系的能量系数

利用超弹性SMA螺栓梁柱节点的耗能能力和自复位特性,将其引入到耗能跨而构建"自复位耗能跨",基于既有的节点试验研究结果对结构体系的滞回性能进行了探讨。在此基础上,以具有旗形滞回特征的单自由度体系为工具,对配置自复位耗能跨低多层钢框架体系的能量系数进行推导。能量系数可以合理量化具有旗形滞回规则结构的峰值响应需求,能量系数越低,表明地震动下结构的峰值响应越低。为了阐明滞回参数对能量系数的影响,对具有不同滞回参数组合可代表低多层结构的等效SDOF体系进行了非线性动力分析,参数组合包括周期、屈服后刚度比、延性系数及能量比。同时对能量系数的离散性也进行了分析。结果表明:能量系数及能量系数的离散性受结构周期、屈服后刚度比及延性系数影响较大,受能量比的影响较小。     

可控消能减震原理及结构分析

本文介绍一种新的减震结构体系及其分析方法。这种结构体系的减震系统由控制装置及耗能装置组成，控制装置根据结构反馈的相关信号，在回头点处启动耗能装置，耗散大量地震能量，属于半主动控制范畴。试验及理论分析表明，这种结构体系的减震效果良好，能够将结构的地震位移反应降低５０％以上。本文介绍了这种结构体系的减震工作原理、数学模型、理论分析方法及算例，并给出了相应的结论。     

单自由度自复位体系设计能量谱研究

本文对具有旗帜型滞回模型的单自由度自复位体系提出了设计能量谱的构造方法,包括设计输入能量谱和设计滞回耗能比谱。首先按中国规范场地类别选取360条实际强震记录进行时程分析,对影响单自由度自复位体系输入能量谱和滞回耗能比谱的参数,包括地震波类型、滞回模型、阻尼比、延性系数等进行研究。在此基础上分别建议了设计输入能量谱和设计滞回耗能比谱及其曲线参数的确定方法,并与实际强震记录计算结果进行比较。结果表明结构滞回模型对能量谱影响明显;阻尼比和延性系数对输入能量谱的影响在整个周期范围内有显著差异,但均有明显的削峰作用。建议的两种设计能量谱综合考虑了结构参数、地震波参数和中国场地类别的影响,可以较好的拟合实际情况,并对弹塑性单自由度自复位体系在地震作用下的耗能需求做出较准确的估计。     

Evaluation of response and energy in actively controlled structures

A computational method of energy evaluation is derived to study the elastic responses and energy distribution of actively controlled single‐degree‐of‐freedom (SDOF) structures during earthquakes. Contrary to the common perception that applying active control force pumps energy into the structure, the applied control force can actually reduce the energy in the structure by reducing the input energy from earthquakes to the structure. In addition, applying control force can dissipate a large amount of energy in the structure when this control force is applied in the direction opposite to the displacement and velocity responses. To demonstrate this energy mechanism in active controlled structures, the two most popular control algorithms, optimal linear control (OLC) and instantaneous optimal control (IOC) algorithms, are used to calculate the control response and energy spectra. One‐step time delay is incorporated into the algorithms to take into consideration the practical aspect of active control. The effects of different earthquakes and damping ratios on control energy and response spectra are studied. These studies show that both OLC and IOC are very effective in reducing the structural displacement and velocity responses by reducing the input earthquake energy as well as dissipating a large amount of energy in the structure. Copyright © 2001 John Wiley & Sons, Ltd.     

公路简支梁桥的地震能量响应分析

利用有限元软件SAP2000建立了某公路简支梁桥的有限元模型,以7条典型强震记录为输入,研究了公路简支梁桥的地震能量响应及其分配规律。结果表明:①地基柔性效应对公路简支梁桥的地震能量响应及其分配规律的影响较小;②当场地土质变软时,地震总输入能、结构阻尼耗能和结构阻尼耗能比均呈递增趋势,而结构滞回耗能和结构滞回耗能比则不断减小,即地基土体作为桥梁动力系统的一部分,增大了系统阻尼,并分担了部分非弹性变形;③随着PGA增大,输入结构的地震能量也增加,导致塑性铰的非弹性变形增加,即结构滞回耗能和结构阻尼耗能增大。     

基础隔震结构的能量设计方法

本文以能量分析方法为基础,解释了基础隔震结构体系的能量设计原理和设计准则。根据作者建立的标准能量设计反应谱曲线,结合我国现行的抗震设计规范,建立了基础隔震结构体系的能量设计方法,通过能量平衡关系对隔层的变形反应进行预测．最后通过算例说明能量设计方法具有一定的可靠性,为该类体系的进一步推广奠定了基础。     

Drop size distribution and kinetic energy load of rainstorms in Hong Kong

Data on drop size distribution and kinetic energy load of rainstorms are basic for rainfall erosivity indices. A simple and relatively inexpensive instrument was used to asses the instantaneous intensity and kinetic energy load of rainstorms in Hong Kong. Both the drop size and the instantaneous kinetic energy load of rainfall in Hong Kong are greater than in temperate and subtropical climates. The high kinetic energy results from the large size and greater number of raindrops falling per unit time. A high correlation between the kinetic energy of rainfall and the amount of rainfall allows for a convenient estimate of the energy load of storms from the amount of rainfall. Of more significance to the erosion process is the determination that about 74% of the total annual rainfall is erosive, containing about three‐quarters of the total annual energy load of the rains. The variability of rainfall parameters within a rainfall and from storm to storm is shown. The energy–intensity relationship, seasonal and annual distributions of rainfall erosivity are presented. Copyright © 2000 John Wiley & Sons, Ltd.     

Application of wavelets to analysis and simulation of earthquake motions

A method of applying wavelet transform to earthquake motion analysis is developed from the viewpoint of energy input structures, in which relationships between wavelet coefficients and energy input, namely energy principles in wavelet analysis are derived. By using the principles, time–frequency characteristics of the 1995 Hyogoken-Nanbu earthquake ground motions are analysed and time histories of energy input for various ranges of frequencies and epicentral distances are identified. Furthermore, a technique to simulate earthquake ground accelerations by wavelet inverse transform is developed on the condition that target time-frequency characteristics are specified. Structural responses to the simulated accelerations are compared with the target time–frequency characteristics, which shows satisfactory correlations between wavelet coefficients and energy responses in both time and frequency domains. Copyright © 1999 John Wiley & Sons, Ltd.     

鲜水河断裂带多断层相互作用的流变断裂力学分析

本文研究了流变介质内多断层的相互影响,通过对鲜水河断裂带的分析,对该断裂带提出一个不共线三断层的断裂力学模型.把介质考虑成流变的,用有限元法结合解析方法求解了流变断裂力学问题的应力、应变及能量场的时空变化.结果表明,多断层的力学场与单一断层的力学场相差甚远,在断层间形成了影响区.在影响区内应力集中,梯度大,分布复杂,应变能在影响区内形成较大范围集中.应变能等值线在孕震期间从影响区向外扩张,能量从外围流向断层区,流动在时空上都是不均匀的,孕育初期增加速率大,后期渐渐平缓.流向影响区的能量比其周围区域大,形成很大梯度.并讨论了地震前兆的某些特征.根据本文的结果,认为在道孚-乾宁-带发生地震的可能性较大.     

判断续发性强震的一种能量标志

一、前言大地震发生以后,几乎无例外地有余震发生。由于历史地震缺失余震的记载,所以早期余震方面的研究很少。近年来由于区域台网建立,加以强震频繁积累了一些余震的记录,因而地震序列活动的研究日渐其多,但过去多偏重于序列活动类型方面的研究,对于—强震序列活动后有无续发性地震的问题研究尚少,本文拟对这一问题进行一些初步探讨。     

Hydromagnetic energy balance equations for the solar atmosphere

Summary Following the pattern established in meteorology, a system of energy balance equations for the solar atmosphere is presented. Since both hydromagnetic and thermodynamic processes are considered, the system includes kinetic, potential, thermal and magnetic forms of energy. Ionization energy is indirectly included in the treatment. The spatial distribution of the energy forms and the processes transforming them are separated into zonal means and departures from such means in order to depict turbulent eddy effects. Where available data concerning solar processes are used in order to appraise certain of the terms which arise.     

Is there a concrete relationship between energy consumption, economic development and environmental load in developing economies? A case study in Shandong Province, China

Shandong Province is currently experiencing fast urbanization and economic booming. However, low energy efficiency, energy shortage and other energy related issues are becoming the limiting factors for further economic development. Based on the analysis of Resource and Environmental Performance Index (REPI) of the past decade, the energy saving index shows that the energy saving level in Shandong fell behind the national average level in China. The sulfur dioxide saving index, however, shows that sulfur dioxide reduction in Shandong was significant. The energy demands of Shandong in 2010, 2015 and 2020 have been forecasted with the environmental load model. In a projected ideal scenario, the energy consumption does not increase with economic development. On the contrary, Shandong can achieve rapid economic development with less energy consumption and affordable environmental load if the industrial structure is being further optimized, technological upgrading efforts are strengthened, strict pollutant control measures are implemented, and reasonable plans for energy development are established.     

2014年8月3日云南鲁甸M6．5地震的地震波能量

根据美国地震学研究联合会（IRIS）的地震能量查询网站公布的地震波辐射能量和能量震级数据,2014年8月3日鲁甸M6．5地震的宽频带（0．5～70 s）能量震级为6．4,2013年4月20日芦山M7．0地震为6．7,相差0．3级,而高频（0．5～2 s）能量震级分别为6．7和6．9,相差0．2级,即芦山地震释放的高频地震波能量为鲁甸地震的2倍。本文根据这些数据对鲁甸地震的特征进行了分析,认为从地震监测的角度,在地震发生后,尽快给出地震波释放能量估计,对于及时确定大地震应急响应级别和采取相应减灾措施是有实际意义的。