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1.
调频液体阻尼器(TLD)的等效力学模型研究 总被引：5，自引：0，他引：5
本文根据流体力学理论,建立了圆柱形ＴＬＤ中晃动液体的势流场,并从液体晃动的动力效应等效原则出发,导出了晃动液体的等效力学模型,并阐明其适用范围。文量计算的结果表明,在工程应用中,仅用ＴＬＤ的一阶晃动等效力学模型就能满足工程需要。 相似文献
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DLS1201机是一种高度智能化、小型轻便、多功能的检查仪,是国内外唯一的基于康普顿背散射扫描（CBS）技术研制成功的安全检查设备。本文对其技术要点和技术指标作了简要说明,并与国内外其他安检仪作了对比。 相似文献
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In this paper,the seismic effectiveness of a density-variable tuned liquid damper(DVTLD) with a sloping bottom is experimentally investigated through a series of shake table tests on a 1/4-scale,3-story frame structure and numerically simulated by a new semi-analytical model.Special attention was given to reducing the fi rst peak and maximum response under near-and far-fi eld ground motions,and the robustness of a density-variable control system consisting of multiple DVTLDs with closely-spaced frequencies.... 相似文献
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Konstantinos Mykoniou Christoph Butenweg Britta Holtschoppen Sven Klinkel 《地震工程与结构动力学》2016,45(11):1779-1796
A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank‐liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross‐interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell‐liquid‐soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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This paper reports on the results of a study conducted on tanks partially filled with water, representing tuned liquid dampers (TLD), subjected to both 1D and 2D horizontal excitations. The sloshing response of the water in the tank is characterized by the free surface motion, the resulting base shear force, and evaluation of the energy dissipated by the sloshing water. A 1D non‐linear flow model capable of simulating a TLD equipped with damping screens is employed to model a 2D TLD. Application of this particular model requires the assumption that the response is decoupled and can be treated as the summation of two independent 1D TLDs. Results from the non‐linear flow model are compared with the 2D experimental shake table test results leading to a validation of the decoupled response assumption. This attractive decoupled response property allows square and rectangular tanks to be used as 2D TLDs, which can simultaneously reduce the dynamic response of a structure in two perpendicular modes of vibration. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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A new experimental method is introduced for determining the relative magnitudes of liquid and vapor diffusion by using a small amount of soluble chemical as a tracer. The theoretical justification of the method is presented for the case where ice is absent. The feasibility of the method is demonstrated by an experiment using marine-deposited clay. 相似文献
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调液阻尼器液体动水压力的模拟 总被引：7，自引：3，他引：4
本文采用流体体积函数法（ＶｏｌｕｍｅｏｆＦｌｕｉｄＭｅｔｈｏｄ,简称ＶＯＦ法）直接求解不可压缩的,粘性的,瞬变和具有自由表面流体的Ｎａｉｅｒ－Ｓｔｏｋｅｓ方程（简称Ｎ－Ｓ方程）计算了矩形容器中液体晃动时动水压力,为便于工程应用,在计算结果发析的基础上,提出了模拟动水压力的经验公式。 相似文献
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The active control of a Tuned Liquid Column Damper (TLCD) with two propellers is presented. A single‐degree‐of‐freedom system with a passive or active TLCD is used as an example to set up the basic equation of motion. The Optimal Control Theory is applied to establish the control law and to calculate the control force generated by these two propellers installed inside the TLCD. A simple pendulum‐like model test is carried out to study the dynamic characteristics of the passive and active TLCDs and the effectiveness of the vibrational control. Comparison of the experimental result with the analytical one shows a good agreement. Finally, the analytical results of the seismic response are also included as an example for demonstration and application. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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立式储液罐地震反应数值分析 总被引：3，自引：0，他引：3
本文采用大型有限元程序ANSYS对立式储液罐的地震反应进行了研究,考虑了不同罐体和内部液体的相互作用,采用3个不同容积的储罐,输入不同强度的地震动时程,进行了大量的数值计算,给出了一些结论。 相似文献
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TLD对海洋平台地震反应控制的简化计算方法 总被引：4，自引：1，他引：4
调频液体阻尼器（Tune Liquid Damper，简称TLD）对地面结构位移反应与加速度反应的较好控制作用已得到理论与试验的验证。本文在此基础上研究了TLD对海洋平台动力反应控制的简化计算方法。计算中，TLD中液体的控制力采用较精确的数值计算法和简化计算法两种方法，通过对海洋平台地震反应计算的结果表明，该简化计算方法具有很高的精度，其结果对海洋平台的抗震设计具有借鉴作用。 相似文献
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Moon Kyum Kim Yun Mook Lim Seong Yong Cho Kyung Hwan Cho Kang Won Lee 《Soil Dynamics and Earthquake Engineering》2002,22(9-12):1151-1158
A three-dimensional soil–structure–liquid interaction problem is numerically simulated in order to analyze the dynamic behavior of a base-isolated liquid storage tank subjected to seismic ground motion. A dynamic analysis of a liquid storage tank is carried out using a hybrid formulation, which combines the finite shell elements for structures and the boundary elements for liquid and soil. The system is composed of three parts: the liquid–structure interaction part, the soil–foundation interaction part, and the base-isolation part. In the liquid–structure interaction part, the tank structure is modeled using the finite elements and the liquid is modeled using the internal boundary elements, which satisfy the free surface boundary condition. In the soil–foundation interaction part, the foundation is modeled using the finite elements and the half-space soil media are modeled using the external boundary elements, which satisfy the radiation condition in the infinite domain. Finally, above two parts are connected with the base-isolation system to solve the system's behavior. Numerical examples are presented to demonstrate the accuracy of the developed method, and an earthquake response analysis is carried out to demonstrate the applicability of the developed technique. The properties of a real LNG tank located in the west coast of Korea are used. The effects of the ground and the base-isolation system on the behavior of the tank are analyzed. 相似文献
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油田企业贮油(液)罐抗震能力评价方法 总被引：3，自引：3，他引：0
油田设施抗震能力评价方法和实践是目前各多地震国家地震工程学术界和工程界广泛关注的课题。本文以贮油(液)罐为研究对象,以其抗震设计方法为依据,开发出其抗震能力评价方法,并用胜利油田立式贮油(液)罐为例,实践了这一方法。 相似文献
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本文研究高层建筑利用调液阻尼器（ＴＬＤ）减小地震反应的方法。首先探讨了激励频率比、调谐频率比对减震效果的影响。在此基础上建立了具有不同ＴＬＤ设置方式的高层建筑体系的学模型和运动方程，首次提出了利用多个ＴＬＤ减小高层建筑多个振型的方法。最后通过数值算例验证了本文方法的有效性。 相似文献
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Umair A. Qureshi Amber R. Solangi Saima Q. Memon Syed I. H. Taqvi Najma Memon 《洁净——土壤、空气、水》2012,40(6):630-639
This study evaluated the adsorptive properties of dibutyl phthalate (DBP) on room temperature ionic liquid (RTIL) modified XAD‐4 resin. The modified RTIL‐XAD 4 sorbent was characterized by FTIR. Effect of varying experimental conditions such as pH, contact time, temperature, shaking speed, concentrations, and interfering species were investigated by batch adsorption experiments. Adsorption was found to be most favorable at pH 6 within 30 min. Experimental data were evaluated in terms of kinetic, equilibrium, and thermodynamic modeling. Kinetics of the sorption was found to follow pseudo second order rate equation whereas Freundlich and D–R isotherms were the most suitable models to explain sorption phenomenon. Thermodynamically sorption was endothermic, irreversible, and spontaneous in nature. 相似文献
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Quantulua-1220型低本底高灵敏度液闪仪是14C测年系统中的关键设备,其质量直接影响14C测年数据的准确性,文中使用中国糖碳、合成本底和成对样品来评估新购置的Quantulua-1220型低本底液闪仪的本底、探测效率及仪器的长期稳定性等重要性能指标是否满足14C测年要求。测试结果表明,在一般工作环境下,液闪仪的本底低于0.5cpm,最大可测14C年龄估计值为48ka;由于猝灭因素引起的年龄偏差不超过100a,新液闪仪经过10个月的运行后,所测定的14C年龄具有可对比性 相似文献
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Evaluation of nitrate levels in groundwater under agricultural fields in two pilot areas in central Chile: A hydrogeological and geochemical approach 总被引：2，自引：0，他引：2 
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下载免费PDF全文 The aim of this study is to evaluate the impact of the application of industrial fertilizers and liquid swine manure in groundwater in two pilot agricultural areas, San Pedro and Pichidegua, which have been under long‐term historic use of fertilizers. A comprehensive hydrogeological investigation was carried out to define the geology and the groundwater flow system. Chemical and isotopic tools were used to evaluate the distribution and behavior of the nitrate in the groundwater. The isotopic tools included δ18O, δ2H, and 3H, which provide information about the origin and residence time of the groundwater; δ15N‐NO3? and δ18O‐NO3?, which provide information about nitrate sources and processes that can affect nitrate along the groundwater flow system. The application rate of liquid manure and other fertilizers all together with land uses was also evaluated. The hydrogeological investigation identified the presence of a confined aquifer underneath a thick low‐permeability aquitard, whose extension covers most of the two study areas. The nitrate concentration data, excepting a few points in zones located near recharge areas in the upper part of the basins and lower areas at the valley outlets (San Pedro), showed nitrate concentration below 10 mgN/L at the regional scale. The isotope data for nitrate showed no influence of the liquid swine manure in the groundwater at the regional scale, except for the high part of the basins and the outlet of the San Pedro valley, which are areas fertilized by manure. This data showed that the regional aquifer on both pilot study areas is protected by the thick low‐permeability aquitard, which is playing an important role on nitrate attenuation. Evidence of denitrification was also found on both shallow and deep groundwater in the Pichidegua site. This study showed that a comprehensive hydrogeological characterization complemented by chemical and isotope data is key for understanding nitrate distribution and concentration in aquifers from areas with intensive agriculture activities. 相似文献
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After the horizontal pendulum is used in ground-tilt measurement, its scaling has drawn great attentions from the people, because without a correct calibration of scale value, the observation is of little application sig- nificance. From the 1920′s, quite a few scholars were engaged in the researches in this respect. And this question was satisfactorily solved until 1962 when Verbaandert (1962) invented the bulging plate, i.e., mercury-cup scaler. After further improvement, the V-M quartz ho… 相似文献
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Vibrator excitation generates not only reflections and refractions of wave fields on the subsurface interfaces but also electromagnetic waves with different frequencies. In this paper, we address the vibration-induced effects on the spontaneous potential field. The effects of controllable vibration on the spontaneous potential field were studied under real field geologic conditions. Experimental data confirmed that the vibration-induced effects on the spontaneous potential field do exist under field conditions. Monitoring records over a long time interval showed that there exist three information zones in the vibration-induced effects on the spontaneous potential field. These are the signal-varying zone, the extremestable zone, and the relaxation-recovery zone. Combined with different well-site data, it was concluded that the time-varying features of the anomalies in the information zones was closely related to the properties of the subsurface liquid （oil and water）. 相似文献
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北京地区流体观测方法记录到的汶川大地震同震变化 总被引：1，自引：0，他引：1
2008年5月12日发生的汶川8.0级巨大地震中,北京地区的一些流体观测仪器记录到了不同程度的同震响应。为了进一步深入研究该次强烈地震对北京地区未来地震活动趋势的影响,系统搜集、整理归纳了该次巨大地震引发的北京地区流体观测仪器记录到的同震响应信息,将北京地区的流体同震现象进行概括,然后分析了数字化流体分钟值观测资料同震效应的表现形态及其变化特征,验证了新安装的一些数字化流体观测仪器的可靠性、灵敏性,对相关流体观测仪器可能存在的一些问题进行了讨论。 相似文献