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1.
This paper systematically analyzes and proves the favorable factors of utilizing the ports and the railways in Northeast China for the Asia-Europe land bridge transportation. It will be more beneficial to Dalian Port and HaDa (Harbin-Dalian) and Binzhou (Harbin-Manzhouli) railways in Northeast China to the Siberia railway in Russia than 1) to other ports and the corresponding railways in China, 2) to the Nakhodka Port in Russia and the corresponding railways and 3) to the Chongjin Port in North Korea and the corresponding railways. This paper also puts forward the reform measures to adopt the ports and the railways in the northeast region in China for the land bridge transportation and the problems in transportation policies and management systems. 相似文献
2.
Effect of Inter-Column Spacing on Soil Stresses due to Vibro-Installed Stone Columns: Interesting Findings 总被引:1,自引:0,他引:1
Hesham Elshazly Mohamed Elkasabgy Azza Elleboudy 《Geotechnical and Geological Engineering》2008,26(2):225-236
This paper reveals the interesting relation between the inter-column spacing and the corresponding alteration of soil state
of stresses due to the vibro-installation technique. This relation is inferred from analyses for load settlement records of
various field load tests, performed for stone columns arrangements with different inter-column spacing values. In order to
have adequate confidence in the findings, a well-documented case history, involving three columns patterns along with their
relevant field and laboratory test results, is utilized for this study. Moreover, a well-tested finite element model, capable
of simulating both elasto-plastic and time dependent soil deformations as well as pore water pressure building and dissipation,
is employed in the analysis. Instead of determining the soil response to the test load, based on known initial soil stresses
and material properties, the analysis is inversely posed to determine the soil initial stresses, based on the recorded settlements
and the post-installation material properties. The alteration in the soil state of stress is represented by the increase in
the post-installation horizontal to vertical stress ratio, K*, as a function of the inter-column spacing. It is found that this alteration experiences a systematic decrease in its magnitude
as the inter-column spacing increases. 相似文献
3.
Full-rangenonlinearanalysisoffatiguebehaviorsofreinforcedconcretestructuresbyfiniteelementmethod¥SongYupu;ZhaoShunbo;WangRuim... 相似文献
4.
5.
A finite element model is set up and experimental tests are performed to help understand the behavior of a concrete canoe and subsequently optimize its design. First, the performance criteria that must be satisfied to participate at the annual ASCE/Master Builders competition are described. Then, the finite element model and the different loading cases that were studied are presented. Results from these loading cases are discussed and used to optimize the material properties as well as the thickness of the hull and the dimensions of the gunwale and reinforcing ribs. Static and dynamic experimental tests were also conducted to validate the results of the finite element analyses. The results indicate that the main stresses and strains are caused by the static load cases. The additional stresses caused during races are small. 相似文献
6.
Experimental studies on the friction coefficient between concrete and the top surface of a rubble mound foundation in China are reviewed. Through comparison of different test results, the development of this research is comprehensively analyzed. An experiment is carried out in the condition similar to prototype. The process curve of friction coefficient with the test block sliding is analyzed and a standard for determination of the friction coetfficient is defined. The variation features of the friction coefficient are analyzed on the basis of the present experimental results and other studies in China. It is shown that the friction coettfficient between concrete and the top surface of a rubble mound foundation decreases with the increase of the foundation pressure, and the friction coettqcient for a very fine leveling bed is smaller than that for a fine leveling bed. 相似文献
7.
8.
Priti Maheshwari P. K. Basudhar S. Chandra 《Geotechnical and Geological Engineering》2006,24(2):313-324
The paper describes a mechanical model for estimating the flexural response of a strip footing, supporting a column (imposing
a concentrated load), resting on a compacted granular bed overlying a reinforcement layer for example, geogrids, geomats etc.
below which lies a loose soil deposit. The footing is idealized as a beam and the reinforcing element is assumed to have finite
bending stiffness and negligible frictional resistance. The upper and lower soil layers are idealized by a series of linear
and discrete springs (Winkler springs) of different stiffness values. To find the response of such a model the governing differential
equations have been derived and expressed in a nondimensional form. A closed form analytical solution of the same has been
obtained subjected to appropriate boundary conditions. Using the present approach the resulting solution for a degenerated
case of a long beam is found to be identical to the same of Hetenyi (1946, Beams on elastic foundations, University of Michigan
press, Ann Arbor, MI). Parametric studies reveal that the ratio of flexural rigidity of upper and lower beam and the ratio
of stiffness of the upper and lower soil layers affect significantly the response of the foundation. 相似文献
9.
在PAKSEY大桥的施工过程中,对节段梁的预制、节段梁的悬臂拼装以及桥面体系的施工进行了精密的测量控制,从而使桥面线形与设计线形的误差最小。 相似文献
10.
在混凝土工程施工时,经常会发现诸如蜂窝、麻面、孔洞、露筋、缝隙、夹层、缺棱掉角、表面不平整。混凝土强度不够,均质性差等质量通病。在分析产生混凝土施工质量问题原因的基础上,有针对性地提出了各种防治措施。 相似文献