The calculations on the cross-section for obtaining the basic properties, i.e., stiffness and strength, are essential for the frame analysis and design using beam-column elements. For regular and simple section shapes, their properties can be easily computed via the closed-form equations. However, when facing to the analysis of the steel and composite sections with a complex shape and complicated material properties, the conventional hand-calculation method is inapplicable. Thus, the numerical analysis method based on the fiber section models is commonly used, but it requires huge computational efforts and usually deficient. Apart from that, our research team has developed the efficient and divergence-free numerical algorithms for arbitrary steel and concrete composite sections with the implementations into the software RCD 2016, where only the steel component is meshed into fibers while the concrete component is automatically divided into layers. A Quasi-Newton iteration method is proposed for determining the section strain distribution and it is numerically stable. This paper reviews the essential theory of the analysis method, as well as the recent developments on the RCD 2016 are summarized. Finally, several featured examples are given for demonstrating the accuracy.