Extending the Black diagram of bitumen to three dimensions

The ordinary Black diagram of bitumen has only two dimensions. Thus, it does not differentiate the complex shear modulus and phase angle measured under different temperature frequency conditions. This study proposes to extend three dimensions by adding a axis. It leads combination multiple necessary plots in same three-dimensional (3D) space. In this 3D space, location, shape, eventually colour plot (either curve or surface) can together indicate unique temperature-dependency time-dependency bituminous binder’s rheological properties, even interplay between them. Hence, polymer-modified is distinguished from neat harder softer bitumen. Furthermore, additional axis also enables direct visualisation precise quantitative evaluations properties various current technical criteria avoiding inconvenient use plots. may lead development practical tool towards more effective efficient evaluation