Some super high arch dams （ SHADs）, like Xiluodu Arch Dam, after their heights reaching the magnitude of 300 m, confront lots of technical challenges in design and construction. Several crucial technologies of 6 SHA...Some super high arch dams （ SHADs）, like Xiluodu Arch Dam, after their heights reaching the magnitude of 300 m, confront lots of technical challenges in design and construction. Several crucial technologies of 6 SHADs will be reviewed and discussed in this and consecutive papers, including Xiluodu, Jinping I in China, Baktiary in Iran, ete. , on the topics of the research method, criterion for evaluation and engineering application of dam safety analysis and evaluation, reasonable dam base interface, dam shape optimization, comprehensive treatments of complex foundation, anti-seismic engineering, dam construction material, concrete placement and temperature control, instrumentation and monitoring of dam operation, etc. This paper will mainly focus on the overall safety of SHADs, reasonable dam base interface analysis and evaluation and their engineering application.展开更多
Based on China National Standard of Soil Engineering Classification (GB/T 50145-2007) and the Unified Soil Classification System of American Society for Testing Materials (ASTM D-2478), two kinds of soil laboratory en...Based on China National Standard of Soil Engineering Classification (GB/T 50145-2007) and the Unified Soil Classification System of American Society for Testing Materials (ASTM D-2478), two kinds of soil laboratory engineering classification methods were discussed and analyzed from the aspects of the definition in particle fraction, classification of soil type and evaluation standard for soil gradation. There is a same limit of fine grains fraction in the two standards, and there are three main types of soil in GB/T 50145-2007 and two in ASTM D-2487. Different evaluation standards of gradation are put forward for gravels and sands in ASTM D-2487. Same criteria of A line, B line and controlling value of plastic index are in the plasticity chart of both standards.展开更多
Initially, Osgood used the integral ∫dr/f（r）for an unicity crite, rion to the differential equation y＇ = f（y）, f （0） = 0. The trivial solution is unique iff this integral goes to the infinite at the origin. Th...Initially, Osgood used the integral ∫dr/f（r）for an unicity crite, rion to the differential equation y＇ = f（y）, f （0） = 0. The trivial solution is unique iff this integral goes to the infinite at the origin. Then he can prove the unicity of the trivial solution of y＇ = y Ln｜Y｜, although the second member is not lipschitzian. Later, Bernfeld [1] shows that all the solutions of y＇ = f（y） do not explose iffthe same integral goes to the infinite at the infinite. Finally, we can adapt a result from the Cauchy works as follows： the trivial solution is a singular solution iffthe same integral vanishes at the origin. Using non standard analysis, we present the proofs of the different criterions and show that the Osgood integral was used by Cauchy before in the similar purpose.展开更多
文摘Some super high arch dams （ SHADs）, like Xiluodu Arch Dam, after their heights reaching the magnitude of 300 m, confront lots of technical challenges in design and construction. Several crucial technologies of 6 SHADs will be reviewed and discussed in this and consecutive papers, including Xiluodu, Jinping I in China, Baktiary in Iran, ete. , on the topics of the research method, criterion for evaluation and engineering application of dam safety analysis and evaluation, reasonable dam base interface, dam shape optimization, comprehensive treatments of complex foundation, anti-seismic engineering, dam construction material, concrete placement and temperature control, instrumentation and monitoring of dam operation, etc. This paper will mainly focus on the overall safety of SHADs, reasonable dam base interface analysis and evaluation and their engineering application.
基金Supported by Projects of National Natural Science Foundation of China ( Nos. 40902077,41111120084,41172236)
文摘Based on China National Standard of Soil Engineering Classification (GB/T 50145-2007) and the Unified Soil Classification System of American Society for Testing Materials (ASTM D-2478), two kinds of soil laboratory engineering classification methods were discussed and analyzed from the aspects of the definition in particle fraction, classification of soil type and evaluation standard for soil gradation. There is a same limit of fine grains fraction in the two standards, and there are three main types of soil in GB/T 50145-2007 and two in ASTM D-2487. Different evaluation standards of gradation are put forward for gravels and sands in ASTM D-2487. Same criteria of A line, B line and controlling value of plastic index are in the plasticity chart of both standards.
文摘Initially, Osgood used the integral ∫dr/f（r）for an unicity crite, rion to the differential equation y＇ = f（y）, f （0） = 0. The trivial solution is unique iff this integral goes to the infinite at the origin. Then he can prove the unicity of the trivial solution of y＇ = y Ln｜Y｜, although the second member is not lipschitzian. Later, Bernfeld [1] shows that all the solutions of y＇ = f（y） do not explose iffthe same integral goes to the infinite at the infinite. Finally, we can adapt a result from the Cauchy works as follows： the trivial solution is a singular solution iffthe same integral vanishes at the origin. Using non standard analysis, we present the proofs of the different criterions and show that the Osgood integral was used by Cauchy before in the similar purpose.
