A kind of new idea based on electromagnetic theory is presented, and it is used in research of the shaping law of electrochemical perforation with fixed cathode. The changing laws of the electric field vectors at cert...A kind of new idea based on electromagnetic theory is presented, and it is used in research of the shaping law of electrochemical perforation with fixed cathode. The changing laws of the electric field vectors at certain point on the surface of the anode workpiece with machining time, such as the electric field intensity E , the current density j and so on, are introduced. The mathematical model of the perforating velocity is presented, moreover, the experimental result to verify it is given at the end of the paper.展开更多
A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ t...A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ test means. The stability of the slope was estimated with several calculation methods, such as the simplified Bishop method and the non-circle analysis method. According to the investigation and analysis results, the factors that may cause the slope failure can be deter- mined as follows: excessive excavating, violating the normal construction procedure, excessive pore water pressure during earlier piling and sudden water-level fluctuation in front of the slope. Measures to improve the soil foundation for reconstructing the port include strengthening the failed slope with vibro sand piles, filling up the crushed stone layer, dividing the excavation into four steps and driving piles by larger intervals. The port now has been successfully reconstructed and begun operation.展开更多
文摘A kind of new idea based on electromagnetic theory is presented, and it is used in research of the shaping law of electrochemical perforation with fixed cathode. The changing laws of the electric field vectors at certain point on the surface of the anode workpiece with machining time, such as the electric field intensity E , the current density j and so on, are introduced. The mathematical model of the perforating velocity is presented, moreover, the experimental result to verify it is given at the end of the paper.
文摘A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ test means. The stability of the slope was estimated with several calculation methods, such as the simplified Bishop method and the non-circle analysis method. According to the investigation and analysis results, the factors that may cause the slope failure can be deter- mined as follows: excessive excavating, violating the normal construction procedure, excessive pore water pressure during earlier piling and sudden water-level fluctuation in front of the slope. Measures to improve the soil foundation for reconstructing the port include strengthening the failed slope with vibro sand piles, filling up the crushed stone layer, dividing the excavation into four steps and driving piles by larger intervals. The port now has been successfully reconstructed and begun operation.
