Sliding fragility of block‐type non‐structural components. Part 2: Restrained components     

D. Lopez Garcia  T. T. Soong 《地震工程与结构动力学》2003,32(1):131-149

This paper focuses on seismic vulnerability assessment of restrained block‐type non‐structural components under sliding response on the basis of seismic inputs specified by current seismic codes. The general representation of restrained equipment considered in this study consists of a rigid block restrained by four post‐tensioned, symmetrically arranged cables. Two sliding‐related failure modes are considered: restraint breakage and excessive absolute acceleration. Fragility analysis is proposed as an appropriate tool to evaluate these failure modes. Sample fragility curves developed through Monte‐Carlo simulations show that the restraint breakage limit state is sensitive to the parameters of the equation of motion. For instance, fragility estimates obtained without taking into account vertical base accelerations can be significantly unconservative for relatively large values of the coefficient of friction. In contrast, the excessive absolute acceleration limit state exhibits little sensitivity to the parameters of the equation of motion. Peak absolute acceleration response is almost always equal to or greater than the horizontal peak base acceleration. Representative results suggest that reasonable response estimates for blocks located at stories other than the ground in multistorey buildings can in general be obtained by simply scaling the ground acceleration to the peak acceleration at the corresponding storey. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

山东惠民凹陷伸展构造及调节带特征   总被引：30，自引：12，他引：30  

王纪祥  陈发景  李趁义 《现代地质》2003,17(2):203-209

综合应用地震、钻井等资料 ,对山东惠民凹陷的伸展构造及调节带特征进行了系统的分析。认为惠民凹陷的总体构造特征是正断层发育 ,构造类型以伸展断块构造 (半地堑和半地垒 )为主。凹陷内一级正断层主要控制着凹陷的沉积和构造特征 ,二级断层控制着构造带(凹陷内的半地垒 )的形成 ,三级及四级断层控制着局部构造的形成或对局部构造起复杂化作用。惠民凹陷具有分区块断构造特征 ,即呈南北分带、东西分块的构造格局 ,纵向伸展断块之间为调节带所调节。分析认为惠民凹陷内发育 2个一级调节带和 5个二级调节带 ,它们多是油气聚集的有利地区。  相似文献   

Morphological and structural relations in the Galilee extensional domain, northern Israel     

A. Matmon  S. Wdowinski  J. K. Hall 《Tectonophysics》2003,371(1-4):223-241

The Lower Galilee and the Yizre'el Valley, northern Israel, are an extensional domain that has been developing since the Miocene, prior and contemporaneously to the development of the Dead Sea Fault (DSF). It is a fan-shaped region bounded in the east by the N–S trending main trace of the DSF, in the north by the Bet-Kerem Fault system, and in the south by the NW–SE trending Carmel Fault. The study area is characterized by high relief topography that follows fault-bounded blocks and flexures at a wavelength of tens of km. A synthesis of the morphologic–structural relations across the entire Galilee region suggests the following characteristics: (1) Blocks within the Lower Galilee tilt toward both the southern and northern boundaries, forming two asymmetrical half-graben structures, opposite facing, and oblique to one another. (2) The Lower Galilee's neighboring blocks, which are the Upper Galilee in the north and the Carmel block in the southwest, are topographically and structurally uplifted and tilted away from the Lower Galilee. (3) The southern half-graben, along the Carmel Fault, is topographically and structurally lower than the northern one. Combining structural and geological data with topographic analysis enables us to distinguish several stages of structural and morphological development in the region. Using a semi-quantitative evolutionary model, we explain the morpho-structural evolution of the region. Our results indicate that the Galilee developed as a set of two isostatically supported opposite facing half-grabens under varying stress fields. The southern one had started developing as early as the early Miocene prior to the formation of the DSF. The northern and younger one has been developing since the middle Pliocene as part of the extension process in the Galilee. Elevation differences between the two half-grabens and their bounding blocks are explained by differences in isostatic subsidence due to sedimentary loading and uplift of the northern half-graben due to differential influences of the regional folding.  相似文献   

利用GIS技术开展安徽省水环境功能区划   总被引：3，自引：0，他引：3  

张卫东 《安徽地质》2002,12(3):180-184，224

根据国家环保总局的要求,笔者以国家测绘局编制的1:25万覆盖安徽全境的数字地图作为空间数据,以水环境功能区划登记表作为属性数据,开发了安徽省水环境功能区划的GIS.介绍了用工作站版Arc/Info7.1和ArcView3.2软件来实现安徽水环境功能区划工作过程.  相似文献   

贵州省1：50万地球化学图编图方法   总被引：1，自引：0，他引：1  

杨永贵 《物探化探计算技术》1997,19(4):370-373

本文是一份编图方法的总结。文中简要介绍了使用计算机编图的方法和技术，它包括从数据入库、参数统计、数据系统偏倚的屏幕动态调整、色区值的选用、色块图的动态显示到图形的绘制等都使用计算机处理。此项技术投入资金少，但经济效益和成图质量好，故具有一定的实用价值。  相似文献   

矿产勘查的新战略   总被引：15，自引：4，他引：15  

谢学锦 《物探与化探》1997,21(6):402-410

本文述及矿产勘查中巨大的风险,并认为减少这种风险有赖于新概念的提出与新技术的发展。列举了作者及其合作者从80年代以来提出的一系列勘查地球化学新概念。在这些新概念的基础上发展了战略性与战术性的深穿透地球化学新技术。据此制定的新的矿产勘查战略可以大大减少矿产勘查风险与不肯定性并降低成本。  相似文献   

Alternative placement technique for antifer blocks used on breakwaters   总被引：1，自引：0，他引：1  

O. Yagci  S. Kapdasli 《Ocean Engineering》2003,30(11):1433-1451

In this study, a placement technique named as “alternative placement technique” was developed for antifer blocks and the results of its application to a breakwater model were presented. This placement technique was compared with the existing techniques such as the “regular placement technique”, the “irregular placement technique” and the “sloped wall placement technique” by experiments. The comparison was carried out considering armor layer stability, prototype placement, clarity of the placement technique’s definition, armor layer cost, and wave runup. As a result of this investigation the “alternative placement technique” was found to be superior to the other existing placement techniques.  相似文献   

New evidence for polyphase metamorphism of glaucophane schist and eclogite exotic blocks in the Franciscan Complex, California and Oregon   总被引：1，自引：0，他引：1  

D. E. MOORE  M. C. BLAKE  Jr. 《Journal of Metamorphic Geology》1989,7(2):211-228

ABSTRACT The early metamorphic history of high-grade exotic blocks in the Franciscan Complex may be more complicated than previously supposed. The different assemblages of high-grade glaucophane schist, eclogite, amphibolite and hornblende schist are commonly considered to have formed at the same time from essentially unmetamorphosed oceanic crust. However, new textural and mineralogical data presented here suggest that high-grade glaucophane schist and eclogite have replaced an earlier epidote-amphibolite facies assemblage that is identical to the primary assemblages in many of the hornblende-rich blocks. At least some of the hornblende-rich blocks may therefore be well-preserved remnants of the earlier metamorphism. Comparison of the mineral assemblages and element partitioning in the mixed-assemblage blocks suggests that the glaucophane schist and eclogite metamorphism took place at slightly lower temperatures but at the same or higher pressures than the earlier, hornblende-forming stage.  相似文献   

层状岩石边坡倾倒破坏过程的数值流形方法模拟   总被引：3，自引：0，他引：3  

刘红岩  秦四清 《水文地质工程地质》2006,33(5):22-25

层状岩石边坡的倾倒破坏是岩石边坡失稳破坏的主要形式之一。本文利用数值流形方法对一层状岩石边坡的倾倒破坏过程进行了模拟。模拟结果表明：在不考虑块体间粘结力的情况下，块体间的摩擦角决定着岩石边坡的稳定性。随着摩擦角的增加，块体间的摩擦系数增大，岩石边坡的稳定性增强，并出现相应的滑动区、倾倒区和稳定区。模拟结果与相应的理论预测结果相吻合。  相似文献   

The principle of discrete element method and its application in the study of regional tectonic stability     

Yue-Quan Shang  Shi-Tian Wang  Hai-Wen Chen 《地震学报(英文版)》1993,6(2):389-395

The basic principle of Discrete Element Method (DEM) is briefly introduced in this paper. Considering advantage of this method that using it the problems on discontinuous deformation of medium can be solved, we apply it to the study on movement of fault-blocks and activity of faults. The results indicate that the DEM has a good prospect in the analysis of regional tectonic stability. Using this method one can calculate the rotary movement of fault blocks, which will provide a new way to explain the stress concentration in some areas and the mechanism of earthquakes. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 456–462, 1992. This study is supported by National Natural Science Fund of China.  相似文献