【单选题】7 / 43轴心受压短柱承载力公式为( )。ANu=0.9φ(fcA+fy′As′)N_u = 0.9\varphi (f_c A + f_y' A_s')Nu=0.9φ(fcA+fy′As′)正确BNu=fyAsN_u = f_y A_sNu=fyAsCMu=fyAsh0M_u = f_y A_s h_0Mu=fyAsh0DV=0.25βcfcbh0V = 0.25\beta_c f_c b h_0V=0.25βcfcbh0参考答案A参考解析Nu=0.9φ(fcA+fy'As')。