In this paper, we developed an effective higher-order beam model which can predict torsional behavior, especially distortion effect, of beam structures with rapidly varying cross-section via asymptotic method. The asymptotic method enables to divide three-dimensional problem into sectional analysis and 1D beam analysis. When performing sectional analysis, we can get interface warping function by applying constraint that torsional warping and distortion are continuous at the interface. An engineering displacement field is assumed by adding the interface warpings to classical beam(Euler-Bernoulli beam) theory. The higher-order beam model is obtained via asymptotic homogenization procedure. Numerical examples show the effectiveness of the present beam model as compared with results of shell finite element model in static analysis.