Design of backfilled thin-seam coal pillars using earth pressure theory     

James G. Donovan  Mario G. Karfakis 《Geotechnical and Geological Engineering》2004,22(4):627-642

In underground coal mining any increase in coal recovery rate is dependent on a decrease in pillar size. Backfilling is one way of reducing the required size of pillars and hence the volume of coal left underground. Therefore any comparisons made between a self-supported mine layout and backfill supported mine layout are based directly on pillar design. The most effective way to examine the effect of backfill on pillar support, and subsequently the rate of recovery, would be to incorporate the mechanisms of backfill support directly into the current design procedure for coal pillars. This paper presents a review of the mechanics of backfill support, a method of estimating the magnitude of that support based on earth pressure theory, and an example that incorporates backfill support into current coal pillar design.  相似文献   

基于分层的面状地图符号设计   总被引：3，自引：1，他引：3  

尹章才  李霖  龙毅  张园玉 《武汉大学学报(信息科学版)》2004,29(12):1111-1114

根据面状符号的结构特征和实现机制 ,提出了基于分层的面状地图符号设计方法 ,把面状符号分为若干层 ,每层采用一种填充方式 ,并在基于VC 的Cartosymbol软件中实现。结果表明 ,该方法既便于地理现象的表达 ,又便于计算机实现。  相似文献   

地理空间的数学定义及定位型地图符号的制约因素分析     

钟业勋 《武汉大学学报(信息科学版)》2004,29(1):29-33

给出了地理空间的数学定义 ,推导了制图区域、地图投影、制图物体及其在椭球面和地图平面上的定位等概念 ,揭示了同一平面位置上可以依制图目的的不同而分别表示多种事物的性质或量值的基本原理 ,阐释了对同一制图区域进行多专题制图的客观条件和物理基础。  相似文献   

基于图论的树状河系结构化绘制模型研究   总被引：5，自引：1，他引：5  

张园玉  李霖  金玉平  朱海红 《武汉大学学报(信息科学版)》2004,29(6):537-539,543

结合树状河系自身的结构特点和图论的思想，提出了基于图论的河系结构化绘制模型的建立，利用图论的思想描述了河系的结构并建立其自动符号化模型，阐述了主流、流向自动确定和结构化绘制实现的详细算法，并对通用图形数据格式DXF文件记录的河系数据进行了测试。  相似文献   

近20年华北地电阻率异常空间演化及强震短期前兆判别标志研究     

郑文俊  田山  邵永新 《中国地震》2005,21(2):260-268

开展了华北地电阻率异常参数提取的研究，以1980—2001年的异常参数为输入进行了全时空扫描，并对其动态图像演化做全面分析，由此提取出华北地区5级以上地震的地电阻率短期前兆的判别标志。为了进行初步检验，本文依上述判别标志对华北近年地电阻率动态图像做了对比分析。  相似文献   

Efficient analysis of pile-group effect on seismic stiffness and strength design of buildings     

Izuru Takewaki  Akiko Kishida 《Soil Dynamics and Earthquake Engineering》2005,25(5):355-367

A new efficient method is developed for the analysis of pile-group effects on the seismic stiffness and strength design of buildings with pile foundations. An efficient continuum model consisting of a dynamic Winkler-type soil element and a pile is used to express the dynamic behavior of the structure-pile-soil system with only a small numerical error. The pile-group effect is taken into account through the influence coefficients among piles which are defined for interstory drifts and pile-head bending moments. It is shown that, while the pile-group effect reduces the interstory drift of buildings in general, it may increase the bending moment of piles at the head. This means that the treatment without the pile-group effect results in the conservative design for super-structures and requires a revised member design for piles.  相似文献   

Statistical Analysis on the Corner Period of Site-Related Design Spectra     

Wu Jian 《中国地震研究》2005,19(1):29-34

INTRODUCTIONFromTJ1 1 74 ,theseismicdesignforbuildingshasbeenbasedontheaccelerationresponsespectruminChina (HuYuxian ,1 988) .ThevalueofTgoftheresponsespectrumvariesbecauseofdifferentsiteclassesanddifferentearthquakeenvironments .Designresponsespectrainc…  相似文献   

Evolutionary aseismic design and retrofit of structures with passive energy dissipation     

G. F. Dargush  R. S. Sant 《地震工程与结构动力学》2005,34(13):1601-1626

A new computational framework is developed for the design and retrofit of building structures by considering aseismic design as a complex adaptive process. For the initial phase of the development within this framework, genetic algorithms are employed for the discrete optimization of passively damped structural systems. The passive elements may include metallic plate dampers, viscous fluid dampers and viscoelastic solid dampers. The primary objective is to determine robust designs, including both the non‐linearity of the structural system and the uncertainty of the seismic environment. Within the present paper, this computational design approach is applied to a series of model problems, involving sizing and placement of passive dampers for energy dissipation. In order to facilitate our investigations and provide a baseline for further study, we introduce several simplifications for these initial examples. In particular, we employ deterministic lumped parameter structural models, memoryless fitness function definitions and hypothetical seismic environments. Despite these restrictions, some interesting results are obtained from the simulations and we are able to gain an understanding of the potential for the proposed evolutionary aseismic design methodology. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

三峡水库区巫山新县城库岸综合治理设计回顾     

刘加龙  张纯根 《中国地质灾害与防治学报》2005,16(3):24-27

三峡水库区巫山新县域库岸综合治理工程范围内涉及到滑坡、泥石流、塌岸等多种地质灾害。治理工程综合运用了多种技术与结构措拖，工程的复杂性和典型性在整个三峡库区具有极强的代表意义。笔者对整个治理方案的布置情况进行了归纳总结，并以翔实的第一手资料对治理工程设计过程中出现的几种典型问题一一进行了分析与论述．提出了相应的解决方案与合理化建议。结论认为，库岸综合治理工作，必须根据不同的地形特征，结合城区总体布局及沿线市政工程建设，综合考虑，有机结合，做到治理和利用相结合，最大限度地改善新城建设用地环境和城市生态环境。设计人员必须依照现场实际条件进行动态设计，确保工程方案合理、可靠、经济。文中讨论的问题和实践经检对同类工程具有一定的借鉴意义。  相似文献   

上海市公共卫生中心空调设计     

寿炜炜  宋静  朱学锦 《中国勘察设计》2005,(8):34-37

介绍了上海市公共卫生中心空调通风的设计特点,突出反映在呼吸道传染病区、呼吸道门诊、呼吸道临检、生物安全实验室的系统设计中,并介绍了空调水系统的特殊要求。  相似文献