Abstract: On?the?basis?of?the?short-term?stiffness?formulas?provided?by?the?current?concrete?cedes?for?prestressed?flexural?member?and?normal?flexural?member,?the?formulas?of?cracking?moment,?pre-cracking?section?stiffness?and?post-cracking?section?stiffness?for?the?horizontal?displacement?calculation?of?cantilever?column?which?under?axial?force?action?and?without?axial?force?action?are?deduced.?Some?parameter?factors?which?having?effect?on?the?axial?force?action?are?analyzed,?such?as?the?elastic?modulus?ratio?of?reinforcement?and?concrete,?the?ratio?of?reinforcement,?the?ratio?of?sectional?effective?height?to?sectional?height,?and?the?axial?force?values,?then?some?qualitative?regularities?about?the?impact?of?foregoing?parameters,?the?interaction?relationship?between?foregoing?parameters?and?axial?force?action?are?obtained?at?the?same?time.?Finally,?the?resuits?of?cantilever?columns?show?that?axial?force?has?a?beneficial?impact?on?the?displacement?of?structure?or?member?in?some?cases.

Key words: axial pressure force , horizontal displacement , cantilever column , section stiffness ;

摘要： 根据现行规范给出的预应力混凝土受弯构件短期刚度公式和普通受弯构件短期刚度公式,推导出了有轴力 作用下和无轴力作用下的悬臂柱开裂弯矩、开裂前截面刚度和开裂后截面刚度的计算公式;在对钢筋弹性模量与 混凝土弹性模量比、截面配筋率、截面有效高度和整截面高度比以及轴力大小等可影响轴力作用的一些参数因素 进行分析的同时,得到这些因素对轴力作用的影响程度以及各因素间互相作用或制约的影响关系等定性规律。最 后,通过悬臂柱的算例可发现,有些情况下,轴力对构件或结构的侧移可产生明显的有利影响。

关键词: 轴压力, 水平侧移, 悬臂柱, 截面刚度