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101.
该软件主要用于地震台站的大量数据处理及行政管理,全部用关系式数据库DBASEⅢ编写,在主菜单的控制下,根据各个工作性质及需要选择适合自己的子菜单。它主要包括两大部分:(1)台站行政管理系统,(2)观测资料管理系统,以及每部分下相应的分支。  相似文献   
102.
本文用钢管混凝土柱作为结构底层耗能柱、用承重墙和隔震器控制结构底层倒塌破坏,从而提出了一种新的耗能-隔震柔性底层结构体系。通过本文12根钢管混凝土柱和文献[7]中7根钢管混凝土柱的低周疲劳实验,初步确定了钢管混凝土柱地震损伤模型的参数;通过两个钢管混凝土-钢筋混凝土三层框架模型和一个纯钢筋混凝土三层框架模型的拟动力实验,研究和比较了两类结构体系的地震损伤。  相似文献   
103.
基于双线性和三线性的力-位移滞回线假设,导出了钢梁阻尼器隔震系统等效阻尼比与阻尼器延性率的关系;为了获得大阻尼比隔震系统,以尽量减小隔震系统的地震反应,求得了使系统阻尼比为最大的阻尼器相应延性率(即最佳延性率)所需满足的条件;给出了在给定地震地面运动输入条件下,使系统阻尼器变形位移达到最佳延性率的阻尼器初始刚度和屈服位移的确定方法。  相似文献   
104.
地球数字产品的空间数学基础   总被引:4,自引:0,他引:4  
在分析当前地球数字产品空间数学基础局限性的基础上,将地图投影概念由传统的曲面到平面的变换扩展为曲面到曲面的变换,提出一套适合于大型GIS和地球数字产品的“地图投影”模型的实用模型,该模型的视图采用等距离切圆柱投影,度量空间是椭球面几何系统,符合计算机环境下GIS视图与度量空间分离的特性。鉴于全球多分辨率连续可视化,精密可视化量算,三维、多维地球数据统一,标准的空间定位框架和只有在统一的空间系统内全球资源、生态环境数据才能进行精确的地理分析等四个方面的需要,从地图投影进到本模型将是方向和技术趋势。  相似文献   
105.
陕北煤炭基地的矿井水资源及利用   总被引:10,自引:2,他引:10  
范立民  李保平 《地下水》2007,29(5):1-3,7
简要论述了陕北地区煤矿开发的水文地质条件,对矿井水资源量、水质及利用途径进行了阐述.该区大型煤矿每天排水1 500~3 000 m3,中型煤矿也有500 m3左右,小煤矿每天排水30~100 m3,利用好矿井疏干水,不仅可以解决能源化工基地建设的用水需求,而且符合国家产业政策和环境保护的要求,是陕北能源化工基地建设的必然选择.  相似文献   
106.
Sinker Butte is the erosional remnant of a very large basaltic tuff cone of middle Pleistocene age located at the southern edge of the western Snake River Plain. Phreatomagmatic tephras are exposed in complete sections up to 100 m thick in the walls of the Snake River Canyon, creating an unusual opportunity to study the deposits produced by this volcano through its entire sequence of explosive eruptions. The main objectives of the study were to determine the overall evolution of the Sinker Butte volcano while focusing particularly on the tephras produced by its phreatomagmatic eruptions. Toward this end, twenty-three detailed stratigraphic sections ranging from 20 to 100 m thick were examined and measured in canyon walls exposing tephras deposited around 180° of the circumference of the volcano.Three main rock units are recognized in canyon walls at Sinker Butte: a lower sequence composed of numerous thin basaltic lava flows, an intermediate sequence of phreatomagmatic tephras, and a capping sequence of welded basaltic spatter and more lava flows. We subdivide the phreatomagmatic deposits into two main parts, a series of reworked, mostly subaqueously deposited tephras and a more voluminous sequence of overlying subaerial surge and fall deposits. Most of the reworked deposits are gray in color and exhibit features such as channel scour and fill, planar-stratification, high and low angle cross-stratification, trough cross-stratification, and Bouma-turbidite sequences consistent with their being deposited in shallow standing water or in braided streams. The overlying subaerial deposits are commonly brown or orange in color due to palagonitization. They display a wide variety of bedding types and sedimentary structures consistent with deposition by base surges, wet to dry pyroclastic fall events, and water saturated debris flows.Proximal sections through the subaerial tephras exhibit large regressive cross-strata, planar bedding, and bomb sags suggesting deposition by wet base surges and tephra fallout. Medial and distal deposits consist of a thick sequence of well-bedded tephras; however, the cross-stratified base-surge deposits are thinner and interbedded within the fallout deposits. The average wavelength and amplitude of the cross strata continue to decrease with distance from the vent. These bedded surge and fall deposits grade upward into dominantly fall deposits containing 75–95% juvenile vesiculated clasts and localized layers of welded spatter, indicating a greatly reduced water-melt ratio. Overlying these “dryer” deposits are massive tuff breccias that were probably deposited as water saturated debris flows (lahars). The first appearance of rounded river gravels in these massive tuff breccias indicates downward coring of the diatreme and entrainment of country rock from lower in the stratigraphic section. The “wetter” nature of these deposits suggests a renewed source of external water. The massive deposits grade upward into wet fallout tephras and the phreatomagmatic sequence ends with a dry scoria fall deposit overlain by welded spatter and lava flows.Field observations and two new 40Ar–39Ar incremental heating dates suggest the succession of lavas and tephra deposits exposed in this part of the Snake River canyon may all have been erupted from a closely related complex of vents at Sinker Butte. We propose that initial eruptions of lava flows built a small shield edifice that dammed or disrupted the flow of the ancestral Snake River. The shift from effusive to explosive eruptions occurred when the surface water or rising ground water gained access to the vent. As the river cut a new channel around the lava dam, water levels dropped and the volcano returned to an effusive style of eruption.  相似文献   
107.
The effectiveness of seismic isolation in protecting structural and non‐structural elements from damage has been assessed in an extensive programme of shaking‐table tests, carried out on four identical 1/3.3‐scale, two‐dimensional, reinforced concrete (R/C) frames. Four different isolation systems were considered, namely: (i) rubber‐based, (ii) steel‐based, (iii) shape memory alloy (SMA)‐based and (iv) hybrid, i.e. based on both SMA and steel components, isolation systems. This paper presents a comprehensive overview of the main results of the experimental tests on base‐isolated models, whose structural response is described through: (i) maximum base displacements; (ii) maximum interstorey drifts; (iii) maximum storey accelerations and (iv) maximum storey shear forces. The evolution of the fundamental frequency of vibration of the R/C frame during the tests is also described. The beneficial effects of using base isolation resulted in no or slight damage, under strong earthquakes, to both structural and non‐structural members, as well as to the internal content of the building. The comparison with the experimental results obtained in shaking‐table tests on similar fixed‐base models emphasizes these positive aspects. Finally, advantages and drawbacks related to the use of each isolation system are discussed in the paper. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
108.
通过对广东西部沿海高速公路路面基层现场压实度检测过程的详细观察,并在不同的条件下反复进行试验、分析比较,找出了影响压实度现场检测精度的主要非理想因素,即标准砂密度、试样含水量和路面基层平整度,并提出了解决方法。  相似文献   
109.
文章阐述了管网测绘数据的GIS建库的基本方法 ,以及计算机监理查错程序对勘测成果的检测。  相似文献   
110.
隔震结构设计与分析软件的研制   总被引:2,自引:0,他引:2  
主要介绍了作者研制的隔震结构设计与分析软件的研制原理、特点和应用范围。结合实例将该软件的分析结果与SAP2000N软件的分析结果进行了比较,结果表明:该软件使用方便,计算结果可靠。  相似文献   
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