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101.
M. Ataur Rahman Sri Sritharan 《地震工程与工程振动(英文版)》2006,5(2):285-296
The unique features of jointed post-tensioned wall systems, which include minimum structural damage and re-centering capability when subjected to earthquake lateral loads, are the result of using unbonded post-tensioning to attach the walls to the foundation, along with employing energy dissipating shear connectors between the walls. Using acceptance criteria defined in terms of inter-story drift, residual drift, and floor acceleration, this study presents a multiplelevel performance-based seismic evaluation of two five-story unbonded post-tensioned jointed precast wall systems. The design and analysis of these two wall systems, established as the direct displacement-based and force-based solutions for a prototype building used in the PREcast Seismic Structural Systems (PRESSS) program, were performed at 60% scale so that the analysis model could be validated using the PRESSS test data. Both buildings satisfied the performance criteria at four levels of earthquake motions although the design base shear of the direct displacement-based jointed wall system was 50% of that demanded by the force-based design method. The study also investigated the feasibility of controlling the maximum transient inter-story drift in a jointed wall system by increasing the number of energy dissipating shear connectors between the walls but without significantly affecting its re-centering capability. 相似文献
102.
介绍了一个安全、实用的分布式网络用户身份认证系统的设计和应用.着重阐述了在IBM Websphere构架下,应用Web Service技术,设计和实现网络用户的统一认证和单点登录,以及认证系统的架构与接口设计、安全性设计、主节点全局用户统一认证模块设计、分节点用户认证集成接口模块设计等. 相似文献
103.
余生晨 《物探化探计算技术》1999,21(2):159-160,164
本文利用经纬网在局部范围的直线性直线的平均freeman链码等于其上任意一点的链码的这一特性,达到自动分离经纬网与等值线的目的,为实现等值线图的自动矢量化打下了基础。 相似文献
104.
An analysis of the V band light curves using the Wilson–Devinney code for GZ Pup, AV Pup and II Aps is provided. The three
systems are found to be of W type with mass ratios of 0.37, 0.8 and 0.295, respectively. A review of the astrophysical quantities
suggests that the systems generally demonstrate properties typical of the W-type contact binaries. 相似文献
105.
IntroductionInChina,thecombinationofseismicdesigncodewithzoningmapofseismicintensityorgroundmotionparametersisusuallyadoptedtodeterminetheseismicfortificationcriterionforthegeneralindustryandcivilbuildings.Thepresentproceduresareasfollows.Accordingtothepro-jectlocation,thedesignbasicaccelerationofgroundmotionandthedesigncharacteristicperiodofresponsespectrumareobtainedfromthezoningmapofseismicgroundmotionparameters(GeneralAdministrationofQualitySupervision,InspectionandQuarantineofthePeople… 相似文献
106.
The evaluation of the fundamental period of shear wall buildings considering the flexibility of the base is investigated in this paper. This research is motivated by the discrepancy reported between the formulas used in different building codes and the measurement of real buildings. Both experimental and analytical approaches are used to assess the effect of the base flexibility on the fundamental period of shear wall structures. In total, twenty buildings built on different types of soil are tested under ambient vibration. The fundamental period is identified using a non‐parametric linear model in the frequency domain. The results show that fundamental period formulas used by UBC‐97 and NBCC‐95 are inadequate since they do not include the effect of the foundation stiffness. To improve the estimation of the fundamental period of shear wall buildings, an analytical approach is presented. The structure and the foundation are represented by a continuous‐discrete system. The stiffnesses of the base are represented by translational and rotational discrete springs. The rigidities of these springs are evaluated from the elastic uniform compression of the soil mass and the size of the foundation. The analytical predictions improve the estimation of the fundamental period and keep the computation simple. The error between the measured period and the analytical results is, on average, less than 10%. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
107.
108.
组合码和相位观测值在线解双差模糊度的算法 总被引:4,自引:0,他引:4
如何在线精确地求解整周模糊度,是GPS高精度动态相对定位的关键问题。在线解算取决于很多因素:基线长度、数据处理方法、接收机的性能(如双频还是单频)以及抗AS和SA的能力等。现代双频GPS接收机能获得载波相位和L1、L2频道上的精度伪距观测值,组合这4个观测值可进行单历元整周模糊度解算。文中对组合码和相位观测值在线解整周度的算法进行了试验和分析,得出了很有实用意义的结合。 相似文献
109.
叙述了中国数字地震台网 (CDSN)数据管理中心 (DMC)的计算机 2 0 0 0年问题 (Y2 K)的解决情况 ,着重介绍了为解决 Y2 K问题而编制的 getdata new软件的功能 ,特点 ,结构和工作原理 ,并结合几个典型实例 ,对用法和应用情况进行说明。另外 ,本文对 getdata new所涉及的部分 ASL的程序也作了简介。 相似文献
110.