Analysis of the value and position of the extreme bending moment and the contraflexure point for the design of the single-span portal frame with hinged connection and a gable roof是什么意思_Analysis of the value and position of the extreme bending moment and the contraflexure point for the design of the single-span portal frame with hinged connection and a gable roof在线翻译_英语_读音_用法_例句