The optimum design of the highway excavation slope angle is one of the most important problems to the highway construction and to the slope improvement. The Dawu Section of Jingzhu (Beijing Zhuhai) Highway is taken a...The optimum design of the highway excavation slope angle is one of the most important problems to the highway construction and to the slope improvement. The Dawu Section of Jingzhu (Beijing Zhuhai) Highway is taken as an example to illustrate the study method for excavation slope angle design. The analysis of the engineering condition from different angles with different factors shows that the stability of the slope is calculated by using residual pushing force and the Sarma method. Then the sensitive analysis of the slope stability is conducted by using residual pushing force method. Finally, the optimum angle of design is presented on the precondition of ensuring the whole stability of slope and the economic reasonability. The study results show that the most sensitive factors are the shear strength parameter and the seismic force, and that the optimum excavation slope angle is 60°.展开更多
利用矩形薄板面内2个不同模态作为工作模态的直线型超声电机,其频率一致性和压电单元的布置方式以及激励方式对电机的性能和效率有重要的影响。该文根据电机定子的位移振型和应变振型详细分析了压电陶瓷的布置方式和激励方式,并利用参...利用矩形薄板面内2个不同模态作为工作模态的直线型超声电机,其频率一致性和压电单元的布置方式以及激励方式对电机的性能和效率有重要的影响。该文根据电机定子的位移振型和应变振型详细分析了压电陶瓷的布置方式和激励方式,并利用参数化有限元方法(finite element method,FEM)对定子结构进行优化设计。设计制作的样机,两相工作模态频率差为270Hz,在电压峰峰值为350V、驱动频率为44.16kHz、预压力为50N的情况下,电机最大空载速度为100mm/s,最大输出力为3N。展开更多
基金theNationalNaturalScienceFoundationofChina (No .40 0 72 0 85 )
文摘The optimum design of the highway excavation slope angle is one of the most important problems to the highway construction and to the slope improvement. The Dawu Section of Jingzhu (Beijing Zhuhai) Highway is taken as an example to illustrate the study method for excavation slope angle design. The analysis of the engineering condition from different angles with different factors shows that the stability of the slope is calculated by using residual pushing force and the Sarma method. Then the sensitive analysis of the slope stability is conducted by using residual pushing force method. Finally, the optimum angle of design is presented on the precondition of ensuring the whole stability of slope and the economic reasonability. The study results show that the most sensitive factors are the shear strength parameter and the seismic force, and that the optimum excavation slope angle is 60°.
文摘利用矩形薄板面内2个不同模态作为工作模态的直线型超声电机,其频率一致性和压电单元的布置方式以及激励方式对电机的性能和效率有重要的影响。该文根据电机定子的位移振型和应变振型详细分析了压电陶瓷的布置方式和激励方式,并利用参数化有限元方法(finite element method,FEM)对定子结构进行优化设计。设计制作的样机,两相工作模态频率差为270Hz,在电压峰峰值为350V、驱动频率为44.16kHz、预压力为50N的情况下,电机最大空载速度为100mm/s,最大输出力为3N。
