八字形刚架拱桥的压力线控制区研究

对常规混凝土拱桥习惯用压力线与拱轴线的吻合程度来衡量拱圈受力是否合理,将此概念延伸引用于所有混凝土结构,如混凝土梁桥(受弯构件),多折线刚架(压弯构件)等,提出在合理施加预应力条件下,总可以使压力线与构件轴线的偏离程度控制在一定范围之内,使全截面处于受压状态。在此基础上提出在适宜条件下具有综合优势的预应力混凝土八字形刚架拱桥,并推导了其压力线包络图控制区为-Ks≤E≤Kx。

Research on the Control Area of Pressure Line of Eight-Shaped Rigid-Frame Arch Bridge

It is well acknowledged that the rationality of force of arch ring can be measured by the level of concord between the pressure line and arch axis concerning traditional concrete arch bridges.So this concept is further applied to all concrete structures like concrete beam bridges(bending members),multi-line rigid frame bridges(compression-flexure members),and soon.It is proved that on the premise of proper prestress to all concrete structures,the extent of eccentricity of pressure line and axis can always be brought under control so as to make full section compressed.On this basis,an advantageous kind of eight-shaped prestressed concrete rigid-frame arch bridge is created under certain circumstance,and its control area of enveloping curve of line of pressure also applicable to all concrete structures is deduced to be-K s≤E≤K x.