In the past decades, many underwater tunnels have been constructed in the mainland of China, and great progress has been made in related tunneling technologies. This paper presents the history and state of the art of ...In the past decades, many underwater tunnels have been constructed in the mainland of China, and great progress has been made in related tunneling technologies. This paper presents the history and state of the art of underwater tunnels in the mainland of China in terms of shield-bored tunnels, drill-and-blast tunnels, and immersed tunnels. Typical underwater tunnels of these types in the mainland of China are described, along with innovative technologies regarding comprehensive geological prediction, grouting-based consolidation, the design and construction of large cross-sectional tunnels with shallow cover in weak strata, cutting tool replacement under limited drainage and reduced pressure conditions, the detection and treatment of boulders, the construction of underwater tunnels in areas with high seismic intensity, and the treatment of serious sedimentation in a foundation channel of immersed tunnels. Some suggestions are made regarding the three potential great strait-crossing tunnels-the Qiongzhou Strait-Crossing Tunnel, Bohai Strait-Crossing Tunnel, and Taiwan Strait-Crossing Tunnel--and issues related to these great strait-crossing tunnels that need further study are proposed.展开更多
Becausethe information contained in a wave function is not enough to describe an individual particle,the suggestion to define the state of a particle by two-wave functions is used.In the double-wave description,a gene...Becausethe information contained in a wave function is not enough to describe an individual particle,the suggestion to define the state of a particle by two-wave functions is used.In the double-wave description,a general formula telling the traversal time of a particle in tunneling is obtained.When the double-wave description over an initial parameter is averaged,it reduces to the usual description.Two new relations between the transmission and the reflected coefficients are founded in the new cescription.展开更多
文摘In the past decades, many underwater tunnels have been constructed in the mainland of China, and great progress has been made in related tunneling technologies. This paper presents the history and state of the art of underwater tunnels in the mainland of China in terms of shield-bored tunnels, drill-and-blast tunnels, and immersed tunnels. Typical underwater tunnels of these types in the mainland of China are described, along with innovative technologies regarding comprehensive geological prediction, grouting-based consolidation, the design and construction of large cross-sectional tunnels with shallow cover in weak strata, cutting tool replacement under limited drainage and reduced pressure conditions, the detection and treatment of boulders, the construction of underwater tunnels in areas with high seismic intensity, and the treatment of serious sedimentation in a foundation channel of immersed tunnels. Some suggestions are made regarding the three potential great strait-crossing tunnels-the Qiongzhou Strait-Crossing Tunnel, Bohai Strait-Crossing Tunnel, and Taiwan Strait-Crossing Tunnel--and issues related to these great strait-crossing tunnels that need further study are proposed.
基金supported by the National Natural Science Foundation of China(Grant No.19774007).
文摘Becausethe information contained in a wave function is not enough to describe an individual particle,the suggestion to define the state of a particle by two-wave functions is used.In the double-wave description,a general formula telling the traversal time of a particle in tunneling is obtained.When the double-wave description over an initial parameter is averaged,it reduces to the usual description.Two new relations between the transmission and the reflected coefficients are founded in the new cescription.
