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1.
Field Static Load Test on Kao-Ping-Hsi Cable-Stayed Bridge   总被引:1,自引:0,他引:1  
Field load testing is an effective method for understanding the behavior and fundamental characteristics of a cable-stayed bridge. This paper presents the results of field static load tests on the Kao-Ping-Hsi cable-stayed bridge, the longest cable-stayed bridge in Taiwan, before it was open to traffic. A total of 40 loading cases, including the unit and distributed bending and torsion loading effects, were conducted to investigate the bridge behavior. The atmospheric temperature effect on the variations of the main girder deflections was also monitored. The results of static load testing include the main girder deflections, the flexural strains of the prestressed concrete girder, and the variations of the cable forces. A three-dimensional finite-element model was developed. The results show that the bridge under the planned load test conditions has linear superposition characteristics and the analytical model shows a very good agreement with the bridge responses. Further discussion of deflection and cable forces of the design specifications for a cable-stayed bridge is also presented.  相似文献   
2.
提出了陶瓷材料疲劳强度衰减理论并由此导出了各种疲劳关系式。建立了疲劳基本方程dσ_r/d_i=一Aσ(t) ̄nt ̄(-m),得出了疲劳寿命公式T=M(σ_0-σ)/Aσ ̄n(静疲劳时M=1,连续增载疲劳时M=n+1,循环疲劳时M=(n+1)/(1+R+R ̄2+……+R ̄n),逐级加载时,并导出不同疲劳方式下疲劳寿命间的关系。同时,用多种Si_3N_4材料在高温中作了论证试验,结果与理论一致。  相似文献   
3.
根据转炉炼钢的物理化学反应机理,从质量平衡和能量平衡的计算出发,通过小参数变动,导出了增量式静态模型中矿石方程和供氧方程的系数。所得结论与新日铁资料基本相符。同时,还进行了炉料和产物的计算,分析了改变废钢比对生产的影响。  相似文献   
4.
After the break-up of Czechoslovakia in 1993 the primary metrological standards authority almost fully remained in Slovakia. So we had to build our primary vacuum metrology anew. But we could do it using uptodate techniques that are more effective and they enable us to fulfil our task more effectively and in a shorter time.The steady demand to widen the lower pressure range and a steady demand for maximal accuracy collide with the financial possibilities open to a small country. So it is impossible to follow the classical pattern for the vacuum standards: liquid columns, static expansion system and dynamic expansion system. But it is possible to utilize contemporary progress in construction of piston manometers. This enables us to discard liquid column and static expansion techniques in favour of piston technique [Tesar J, Prazak D. Vacuum 2002; 67: 311, Tesar J, Prazak D, Krajicek Z. In:Proceedings of international symposium on Pressure and Vacuum, 2003. p. 169, Tesar J, Repa P, Prazak D, Krajicek Z, Peksa L. Vacuum 2004; 76: 491.]. Such system fulfils all the needs of a little industrial country and is economically acceptable.  相似文献   
5.
The effects of ionic strength on myofibrils and myosin from rabbit fast-twitch Psoas major (PM) and slow-twitch Semimembranosus proprius (SMp) muscles before and after heating were studied by electron microscopy and thermal scanning rheometry. The direct suspension of proteins in low ionic strength (0.2M KCl; pH 6.0) led to very weak gels, whereas a gradual lowering of the ionic strength (by dialysis against 0.2M KCl; pH 6.0) of 0.6M KCl protein solutions induced strand-type networks at low temperature and strong heat-induced gels. As shown by transmission and scanning electron micrographs, in low ionic strength, SMp myosins formed shorter filaments before heating and thinner and shorter structures in heat-induced gels, as well as a lower gel porosity than PM myosins.  相似文献   
6.
动态光散射法研究海藻酸钠凝胶松弛行为   总被引:5,自引:0,他引:5  
在前文的基础上,用相关函数轮廓分析的方法剖析了运动模型模式的复杂性。通过海藻酸钠水溶液在0.1mol/LCaCl2水溶液透析凝胶化过程中交联网络的松弛时间谱表明它不是单一的峰,有两上特征运动模式,并随透析向更慢的运动模式发展,这很慢的运动模式估计与区域的结构的生成有关。  相似文献   
7.
The effect of gas-liquid contacting conditions in a static mixer on ozone transfer efficiency and reduction of Bacillus subtilis spores was studied in an experimental ozone contactor. An empirical mathematical model was developed that related the transfer efficiency in the experimental system to the superficial liquid velocity in the mixer, the gas-liquid flow rate ratio and the height of the down-stream bubble column. Spore reduction was determined primarily by the dissolved ozone concentration-time (Cavgtm) product in the reactive flow segment and was independent of the gas-liquid contacting conditions in the static mixer. In an integrated ozone contacting system, the static mixer should be designed to maximize ozone mass transfer while the reactive flow segment should be designed for efficient microorganism reduction.  相似文献   
8.
中原高温高盐油藏疏水缔合聚合物凝胶调剖剂研究   总被引:3,自引:1,他引:2  
针对中原油田高温(>80℃)、高盐度(>50 g/L)、高硬度(>1 g/L)砂岩油藏,研制了地下成胶的高热稳定性聚合物凝胶调剖剂。所用聚合物为疏水缔合聚合物AP-P4,M=9.0×106,HD=27%,疏水基摩尔分数0.2%;交联剂为可生成酚醛树脂的3种化合物;调剖剂胶液用矿化度160 g/L的马寨油田污水配制;实验温度95℃。根据形成的凝胶黏度(95℃,1.1 s-1)确定交联剂各组分用量为:MZ-YL 0.429%,MZ-BE 0.060%,MZ-XS 0.012%;酸度调整剂用量0.12%;成胶时间10~15小时。2.5、3.0、3.5 g/L AP-P4的凝胶在95℃老化100天后黏度保持在~40 Pa.s及以上。初配制胶液在3000 r/min下剪切15分钟后黏度降低87.5%~89.0%,但成胶后和老化过程中凝胶黏度只比未剪切样降低17.1%~6.6%。3.5 g/L AP-P4的调剖剂对~1μm2的6支储层岩心的堵塞率在88.1%~95.8%范围,平均93.3%,造成的残余阻力系数在15.2~28.6范围,平均19.8,使渗透率级差2.3~8.0的4组双人造岩心的注水流量比发生不同程度的反转。认为该凝胶调剖剂高温下稳定性好的原因,是强化学交联密度低,因而凝胶脱水收缩作用弱。图2表5参5。  相似文献   
9.
The rising global demand for energy has triggered emphasis on conservation of energy. Buildings are one of the important energy consuming sectors. Passive solar architecture encompasses a wide range of strategies and options resulting in energy efficient building design and increased occupant's comfort. Passive solar design, aiming at increasing direct solar gains during winter period and to avoid overheating during summer period should make use of specific shading devices over energy efficient window. The static sunshades are most effective for solar control inside the buildings.Countries like India have composite climate, which can be classified under summer, winter and rainy season. Depending on the seasonal requirements, this paper introduces a new geometry of a static sunshade, designed by calculating the sun angles for the two dates. The static sun shading design methodology is validated with the help of small scale modeling experimentation technique, carried out in Pilani, Rajasthan (India). Although insulating materials can be used as a part of a building structure, its feasibility should be checked before particular application. In the present paper, the two small-scale experimental models of actual construction material with varying static sunshades, i.e. horizontal and the proposed one have been constructed and analyzed with the models of insulating material (Polyurethane Foam [PUF]). Depending upon the solar intersection over south facade wall, sunlit area and shaded area have been correlated with temperature inside the models to decide the effectiveness of the proposed sunshade.  相似文献   
10.
本文详细介绍了变频调速节能改造方案的经济性评价方法。静态分析法包括投资回收期法、抵偿年限法和年计算费用法;动态分析法则包括净现值法、内部回收率法、总费用现值法和最小年费用法。  相似文献   
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