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51.
高精度重力资料在胜利油区油气藏探测中的应用 总被引:2,自引:0,他引:2
摘要:应用改进的重力归一化总梯度法(GH法)对胜利油田DB区的高精度重力测量资料进行了处理。计算了GH值在地下的三维分布。某一深度GH平面等值线图中的闭合极小值(GH低)反映了低密度体的存在及其水平位置,而不同深度等值线图中GH低的数目的变化可以近似表示低密度体集中的深度范围。GH平面等值线图还可以为选择GH铅垂断面图的方向提供依据。GH铅垂断面等值线图中的闭合极小值更清楚地显示出低密度体的形态及其近似深度。计算出的GH值的三维分布与钻井资料的比较表明,GH的闭合极小值与已知油气藏在位置上有较明显的相关关系。 相似文献
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53.
Experimental study of deformable connection consisting of buckling‐restrained brace and rubber bearings to connect floor system to lateral force resisting system
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Georgios Tsampras Richard Sause Robert B. Fleischman Jose I. Restrepo 《地震工程与结构动力学》2017,46(8):1287-1305
This paper presents experimental and numerical studies of a full‐scale deformable connection used to connect the floor system of the flexible gravity load resisting system to the stiff lateral force resisting system (LFRS) of an earthquake‐resistant building. The purpose of the deformable connection is to limit the earthquake‐induced horizontal inertia force transferred from the floor system to the LFRS and, thereby, to reduce the horizontal floor accelerations and the forces in the LFRS. The deformable connection that was studied consists of a buckling‐restrained brace (BRB) and steel‐reinforced laminated low‐damping rubber bearings (RB). The test results show that the force–deformation responses of the connection are stable, and the dynamic force responses are larger than the quasi‐static force responses. The BRB+RB force–deformation response depends mainly on the BRB response. A detailed discussion of the BRB experimental force–deformation response is presented. The experimental results show that the maximum plastic deformation range controls the isotropic hardening of the BRB. The hardened BRB force–deformation responses are used to calculate the overstrength adjustment factors. Details and limitations of a validated, accurate model for the connection force–deformation response are presented. Numerical simulation results for a 12‐story reinforced concrete wall building with deformable connections show the effects of including the RB in the deformable connection and the effect of modeling the BRB isotropic hardening on the building seismic response. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
54.
Response of hybrid isolation system during a shake table experiment of a full‐scale isolated building
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Keri L. Ryan Taichiro Okazaki Camila B. Coria Eiji Sato Tomohiro Sasaki 《地震工程与结构动力学》2018,47(11):2214-2232
A full‐scale 5‐story steel moment frame building was subjected to a series of earthquake excitations using the E‐Defense shake table in August, 2011. For one of the test configurations, the building was seismically isolated by a hybrid system of lead‐rubber bearings and low friction roller bearings known as cross‐linear bearings, and was designed for a very rare 100 000‐year return period earthquake at a Central and Eastern US soil site. The building was subject to 15 trials including sinusoidal input, recorded motions and simulated earthquakes, 2D and 3D input, and a range of intensities including some beyond the design basis level. The experimental program was one of the first system‐level full‐scale validations of seismic isolation and the first known full‐scale experiment of a hybrid isolation system incorporating lead‐rubber and low friction bearings. Stable response of the hybrid isolation system was demonstrated at displacement demands up to 550 mm and shear strain in excess of 200%. Torsional amplifications were within the new factor stipulated by the code provisions. Axial force was observed to transfer from the lead‐rubber bearings to the cross‐linear bearings at large displacements, and the force transfer at large displacements exceeded that predicted by basic calculations. The force transfer occurred primarily because of the flexural rigidity of the base diaphragm and the larger vertical stiffness of the cross‐linear bearings relative to the lead‐rubber bearings. 相似文献
55.
Jong‐Cheng Wu 《地震工程与结构动力学》2000,29(9):1325-1342
Recently, the application of active control to seismic‐excited buildings has attracted international attention. To demonstrate the practical applicability of active control, we have conducted experimental tests using a full‐scale three‐storey building equipped with active bracing systems on the shake table at the National Center for Research on Earthquake Engineering (NCREE), Taiwan. Experimental results indicate that the control–structure interaction (CSI) effect is significant. A state‐space analytical model of this actively controlled building taking into account the CSI effect is established in this paper using a system identification technique based on curve‐fitting of transfer functions. To verify the accuracy of the analytical model for simulating the controlled response, four sets of linear quadratic Gaussian (LQG) controllers using acceleration feedback are designed and further experimental tests are conducted for comparison. It is demonstrated that the correlations between the simulation and experimental results are remarkable. The construction of an accurate analytical model is important for active control, and such an analytical model can be used for future benchmark studies of different control algorithms based on numerical simulations. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
56.
This paper describes the results obtained from the full‐scale measurements of wind effects on a 70‐storey building in Hong Kong. The building which has a height of approximately 370 m is the second tallest structure in Hong Kong. The field data such as wind speed, wind direction and wind‐induced acceleration responses have been measured since 1995 including the close passage of two typhoons; typhoon Sally and typhoon Kent. Detailed analysis of the field data is conducted. The full‐scale measurements are compared with the wind tunnel results obtained in the Boundary Layer Wind Tunnel Laboratory at Western Ontario University. The amplitude‐dependent characteristics of damping and natural frequency that were obtained by using the random decrement technique are investigated. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
57.
国家1:50000数据库更新工程总体设计研究与技术创新 总被引:6,自引:2,他引:4
为了全面提高1:50000数据库的信息现势性和要素完整性,我国"十一五"期间组织实施了国家1:50000数据库更新工程.介绍该工程总体技术研究与技术创新工作,包括研究设计以地形数据全要素更新、全区域变化检测和全过程质量控制为主要特征的1:50000数据库全面更新模式,研究提出符合我国大面积快速更新实际需要的缩编更新优先、影像一体化更新为主的主体更新方法,设计研制规模化更新所需的生产技术系统,制定配套的生产技术规定,建立规模化更新生产业务体系,并在全国大规模更新生产中广泛使用.Abstract: The currency of geographic data refers to its consistency with respect to the real world, and plays a criti-cal role in geographic information service and applications. In order to improve the quality of geographic informa-tion service, State Bureau of Surveying and Mapping of China had launched a five year's national campaign to up-date 1 : 50000 topographic database. This paper outlines the master design and technical development of this na-tional updating engineering, which adopts a full coverage updating strategy characterized by all element topo-graphic data modeling, change detection in all related areas, and whole process data quality controlling. High resolution image-based updating and large-scale data generalization-based updating were developed and used as two majors updating techniques, a series of technical production specifications were made, Based on the above, a technical system for large scale updating production, mainly including image based updating software and data generalization based updating software, has been developed and equipped to a large number of production units. The new technical pro-duction system has been successfully implemented in national campaign to update 1 : 50000 topographic database. 相似文献
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59.
Beerkan multi-runs for characterizing water infiltration and spatial variability of soil hydraulic properties across scales 总被引:1,自引:1,他引:0
Laurent Lassabatere Simone Di Prima Rafael Angulo-Jaramillo Saskia Keesstra David Salesa 《水文科学杂志》2019,64(2):165-178
A method is presented for characterizing the spatial variability of water infiltration and soil hydraulic properties at the transect and field scales. The method involves monitoring a set of 10 Beerkan runs distributed over a 1-m length of soil, and running BEST (Beerkan estimation of soil transfer parameters) methods to derive hydraulic parameters. The Beerkan multi-runs (BMR) method provides a significant amount of data at the transect scale, allowing the determination of correlations between water infiltration variables and hydraulic parameters, and the detection of specific runs affected by preferential flow or water repellence. The realization of several BMRs at several transects on the same site allows comparison of the variation between locations (spatial variability at the field scale) and at the transect scale (spatial variability at the metre scale), using analysis of variance. From the results, we determined the spatial variability of water infiltration and hydraulic parameters as well as its characteristic scale (transect versus field). 相似文献
60.
针对钢筋混凝土梁与钢管混凝土柱的穿筋连接形式,研究了钢管开穿筋小孔及加固对钢管混凝土柱抗震性能的影响。对于未开孔、开孔和开孔并加固三种情况,进行了3个直径为610 mm的足尺钢管混凝土柱试件的低周反复荷载试验。试验结果表明:未开孔试件在距根部100 mm处发生钢管屈曲破坏;开孔试件的破坏主要是开孔处屈曲撕裂,开孔对钢管混凝土柱初期刚度和峰值承载力影响不大,但在峰值承载力后受孔边撕裂破坏影响,开孔试件的刚度和强度退化较快、延性和耗能能力降低;开孔并加固试件的破坏位置上移至加固段上部约90 mm处,与未开孔试件表现出相似的抗震性能。 相似文献