拾振器输入信号恢复方法的研究   总被引：1，自引：0，他引：1  

杨振宇  高峰  刘志言  沈毅  马树林 《地震工程与工程振动》2005,25(1):172-175

为了补偿由于拾振器及其测量系统有限带宽而使测量结果产生的测量误差，本文提出了一种用FIR横向滤波器来恢复拾振器原始输入信号的方法。该方法是将拾振器的输出信号作为FIR横向滤波器的输入，用自适应RLS算法对FIR横向滤波器系数进行辨识而最终获得可以恢复拾振器原始输入信号的反卷积滤波器。通过用几组不同特点的信号对其进行实验检验，结果证明该方法的有效性和较好的泛化能力。  相似文献   

基于特征结构配置的结构鲁棒控制算法及仿真   总被引：2，自引：0，他引：2  

王国胜  张春巍  段广仁  欧进萍 《地震工程与工程振动》2005,25(2):125-129

本文提出了结构系统的鲁棒主动控制算法，其目的是求取状态反馈控制律，在闭环系统具有希望特征值前提下，使得闭环系统特征值关于参数摄动具有最小的灵敏度。基于状态反馈特征结构配置参数化方法和矩阵特征值灵敏度分析理论，该问题转化为含有约束条件的优化问题，并给出了求解该鲁棒控制问题的算法。该方法给出了特征值灵敏度函数的参数化表示，且直接基于结构系统矩阵，故便于工程应用。三自由度层间剪切型结构地震作用下的仿真分析，表明所提方法的有效性。  相似文献   

强夯振动监测应用分析   总被引：5，自引：0，他引：5  

褚宏宪  史慧杰 《物探与化探》2005,29(1):88-92

结合强夯振动监测的应用实例,阐述了强夯振动监测的原理方法和成果分析过程,以及强夯振动监测应注意的问题。对强夯施工引起的地面振动进行同步监测分析,可给出强夯振动影响的地震烈度评价、振动主频、振动速度参数和振动安全距离。  相似文献   

Numerical simulation of the steam-water flow instability as a mechanism of long-period ground vibrations at geothermal areas   总被引：1，自引：0，他引：1  

Kota Iwamura  Satoshi Kaneshima 《Geophysical Journal International》2005,163(2):833-851

  相似文献   

建筑物下爆破地震效应的研究——"爆破安全规程"的应用与修正     

黄永祥  黄浩雄  李雄  魏正国  李正光  吕富洲  张云军  黎家佑  朱振华  吕其昆  杨佐  赵庆和 《地震研究》2002,25(3):287-294

叙述了大姚铜矿的大药量爆破振动效应观测,研究了在建筑物下的爆破施工中,如何确保建筑物安保证安全生产最大用药量的问题,结合“爆破安全规程”药量指数m的应用与修正,从而得出正在对爆破上方的建筑物地面爆破振动动加速度a,速度v随爆心距地面投影r与爆心深度h之比值（r/h)的衰减变化规律;发现临近正对爆心的地面振动有强心现象,并定义它为“极震”效应;定义“极震”效应系数N为正对爆心实测加速度a或速度v与用振动衰减普适式求得值a'或v'之比（N＝a/a',或N=v/v'）。经多年的安全生产证明,采用振动衰减普适式（药量指娄m=1/3)和“极震”效应系数修正法,效果良好,获得生产最佳用药量,民房安全率达98％左右。  相似文献   

Dynamic performance of cable-stayed bridge tower with multi-stage pendulum mass damper under wind excitations—Ⅱ: Experiment   总被引：1，自引：0，他引：1  

郭安薪  徐幼麟  李惠 《地震工程与工程振动(英文版)》2007,(4)

The possibility of using a multi-stage pendulum mass damper (MSPMD) to control wind-induced vibration of a single column tower of a cable-stayed bridge during construction was studied theoretically in part I of this work. In this paper, the performance of the MSPMD for reducing bridge tower vibration is studied experimentally. A MSPMD model and a tower model of the bridge with geometry scaling of 1:100 were designed and manufactured. Calibration of the MSPMD model with different wire lengths is conducted to verify the analytical model of the damper. A series of tests for the uncontrolled freestanding tower, tower with cables, and tower with MSPMD model are then performed under harmonic and white noise excitations. The experimental results show that the responses of the tower model signif icantly decrease with the installation of the MSPMD model, which demonstrates the effectiveness of the MSPMD to mitigate the vibration of the bridge tower.  相似文献   

强非线性杜芬系统随机振动的等效化研究     

樊友景  石志晓  李大望 《世界地震工程》2007,23(3):29-31

以相对穿阈率为评估指标，探讨了强非线性杜芬系统稳态随机振动的等效化问题。结果表明，在不同位移阈值条件下，随着系统振动非线性的增强，立方恢复力等效模型预测精度逐步提高。该等效模型对强非线性杜芬系统具有良好的适用性。  相似文献   

基于动力可靠度的隔震结构参数模糊优化   总被引：1，自引：0，他引：1  

杜永峰  白莉  李慧  张丽娟 《世界地震工程》2007,23(3):60-67

分别选取Bouc—Wen和退化Bouc—Wen模型描述隔震层及上部结构滞变回复力，采用虚拟激励法进行隔震结构随机响应分析。用各层最大层间位移响应和累计疲劳损伤指数建立双参数的功能状态方程，用一次二阶矩理论计算隔震结构失效概率。选用一个隔震框架作为数值算例，探讨了低频过滤器、隔震阻尼比和隔震刚度对隔震结构各子系统条件失效概率的影响。建立了隔震结构参数多目标优化模型，用失效概率确定单因素评判的隶属度，并采用最大隶属度法对隔震参数进行模糊优化。  相似文献   

The Frequency Content of Ground Vibration     

D. P. Blair 《Fragblast: International Journal for Blasting and Fragmentation》2004,8(3):151-176

A detailed examination of the frequency content of ground vibration is presented in terms of the so-called instantaneous frequency and time-frequency analysis. These techniques, and others, are applied to the surface vibration from a mass blast that triggered a large seismic event and to an earthquake vibration measured in the walls of a massive dam. As an associated issue it is shown that the relationship between peak levels of acceleration and velocity also reveals information on the frequency content of ground vibration. It is demonstrated quite clearly that the popular zero-crossing method cannot be used to obtain the frequency associated with the peak vibration level. In fact it is a false notion that one particular frequency can be associated with the peak level except for the ideal (and impractical) case of a single sinusoid. Realistically, there is a distribution of frequencies associated with the peak level, and a technique of sliding filters is suggested in order to examine the dependence of the peak level upon this frequency content. In light of the sliding filter approach, a new frequency dependent criterion for allowable levels of vibration is presented. This criterion is a completely continuous and well-defined function of frequency and so is more realistic than the current criteria which are only piecewise continuous and based upon an ill-defined frequency. The new criterion is applied to vibration data obtained from quarries and underground operations and is also applied to a model of resonant vibrations in urban dwellings.  相似文献   

A Feasibility Study on Controlling Ground Vibrations Caused by Blasts in Malmberget Underground Mine     

Z. X. Zhang  P. -A. Lindqvist  T. Naarttij  rvi  K. Wikstr  m 《Fragblast: International Journal for Blasting and Fragmentation》2004,8(1):3-21

In order to control or reduce the ground vibrations caused by underground blasts in Malmberget mine, a number of blast tests were carried out during production blasts and a series of single shot waveforms were obtained. Then the single shot waveforms from the same ring or different rings were analysed and compared with each other. The results showed that the single shots are reproducible, meaning that the ground vibrations caused by underground blasts can be controlled by means of the interference of the vibration waveforms measured. Finally, a formal test using electronic detonators and employing an optimum delay time of 8 ms was done in production. The test for an 11-borehole ring shows that the maximum vertical ground vibrations are reduced to the maximum vertical vibrations of a single shot. Particularly, the total vibration history for the 11-borehole-ring blast is shortened to about 200 ms over a velocity of 2 mm/s. However, the total vibration history of a normal production blast of 11-borehole ring is always 1400 ms over a velocity of 2 mm/s, namely the total vibration time of a production blast can be reduced to one seventh of that of the common production blasts by using the vibration control method. This indicates that the vibration control method introduced in the paper is feasible for underground mining blasts.  相似文献