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121.
It may be safely presumed that few of us who have worked in the field as a geological surveyor would dissent in making an open confession of our unfortunate attitude towards igneous rocks particularly those of a massive form. These obstacles, as one is apt to regard them, are the unruly bodies 相似文献
122.
Die palaeozoischen Pflanzen der Provinz Suiyuan sind bisher sehr wenig bekannt. Die in der vorliegenden Arbeit beschriebenen Pflanzen stammen aus dem sogenannten "Tachingshan Range" namentlich aus den Localitaten Tungshengmao und Kumenyintien. Die Fundorte liegen also etwa an der Grenze 相似文献
123.
The fragment of fossil wood forming the main subject of this paper was collected by P. Teilhard de Chardin when he was sent to Sinkiang by the Geological Survey of China, with the Haardt-Citroen Expedition (1932). 相似文献
124.
Two- and three-dimensional finite element analysis programs for pile-soil interaction are compiled. Duncan-Chang's Model is used. The construction sequence of the pier is modeled. The pile-soil interface element is used. The influence of the combination type of piles on the deformation of bank slope and pile behaviour is analyzed. Different designs of a pile-supported pier are compared thoroughly. Calculation results show that the stresses and displacements of the pile are directly related to the distance from the bank slope and the direction of inclination. An inclined prop pile set in the rear platform would remarkably reduce the stresses of piles and the displacement of the pier. 相似文献
125.
Xie Wei Tang Xinming Engineer China Offshore Oil Development & Engineering Corporation Tianjin 《中国海洋工程》1993,(3)
The quasi-static analysis method introduced by API RP 2P is well known and accepted as a very useful mooring analysis method. In the early design stage, this method is widely used for preliminary analysis and mooring parameter selection. However, the quasi-static method of API RP 2P is developed for single-floating-body condition, i. e., only one floating body is considered in the computation procedure. Difficulties arise when it is used for the analysis of a CALM system, which is comprised of two floating bodies (tanker and buoy). This paper presents an analysis procedure for a two-floating-body system based on the quasi-static procedure of API RP 2P with some modifications reflecting special characteristics of the CALM system. Finally, the analysis results of a CALM system are given to illustrate the use of this procedure. 相似文献
126.
Tao Tongkang Yu Long Yan Jun Dong Zhiyong
Prof. Senior Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing
Graduate Student Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Associate Professor Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1997,(2)
This paper investigates the performance of geomembrane composites used as impervious andheat-insulating lining within a breakwater for a power station.The seepage field,distribution ofstress-strain contour and seepage discharge of hot water which has been treated as the inner thermalsource in the calculation of heat-insulation,have been given by three-dimensional calculation method coup-ling seepage with stress.The results indicate that the impervious and heat-insulation effect ofgeomembrane composites is significant. 相似文献
127.
Yu Ke Su Weidong Postgraduate River Harbour Department Nanjing Hydraulic ResearchInstitute Nanjing Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(1)
Generally, the reliability of ami -sliding and anti-overturning stability of an isolated gravity cylinder in a certain working period can be evaluated only when the statistical properties of short term stability are given first. The authors used numerical method to simulate the stability state function of a cylinder in short-crested sea, and further to get the probabilitical characteristics of the structure's stability by time domain analysis. The external loads appeared in the state functions include horizontal wave force, lift force and the respective moments, and the loads are correlated by co- spectrum. The numerical method presented in this paper can be used not only to solve short term reliability problem directly, but to calculate and analyse the long term reliability problem as well. For circular cylinders, an example of simulation and analysis is displayed in this paper. 相似文献
128.
Yao Guoquan Ma Zhixiong Ding Bingcan Prof. Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1993,(3)
This paper proposes ten types of improved floating breakwaters for experiment with regular waves, based on the experience in the development and manufacture of existing floating breakwaters both at home and abroad, and on the results of experimental studies on the hydraulic characteristics of several types of floating breakwaters. The wave heights before and behind the breakwaters are measured, the movements of floating breakwaters are observed and the chain forces of the floating breakwaters are measured. The paper studies and compares the hydraulic characteristics of the improved rectangular floating breakwaters of which the internal and external structures and their installation methods are changed. Finally the optimal type of structure is selected through experiments. 相似文献
129.
Jin Xianding Sun Renzhang Rrofessor Dept. of Naval Architecture Ocean Engineering Shanghai Jiao Tong University Shanghai Engineer Applied Software Development Center of China State Shipbuilding Corp 《中国海洋工程》1994,(1)
-This paper reviews the current methodology for dynamic reanalysis. Rayleigh-Ritz approach and receptance approach are discussed in detail. Based on a general finite element structural analysis program SAPS, an eigenproblem re-analysis prorgram ERP was compiled. With a very small change the program can be implemented readily with any general FEM program. Finally, some numerical examples show that the new algorithm is of high precision and efficiency. In the case of local modification in the offshore platform, the efficiency is raised by 20- 50 times when compared with the re-calculation of the whole model. 相似文献
130.
The application of wireline formation tester(WFT)gradually extends in oil-field with the constant improvement of instrument functions.Applications of WFT in oil and gas exploration in Tarim Oilfield,such as formation pressure measurement,are described,and testing efficiency between drill stem testing(DST)and WFT are compared,especially comprised of PVT sampling,hydrocarbon composition estimation,fluid characterization analysis and formation permeability analysis.The test results between WFT and traditional DST show that their functions can be complementary.The influence factors of WFT and the suitable applying conditions for WFT and DST are also discussed. 相似文献