Architecture Engineering and Science

 Urban catalyst theory is based on the excavation of the phenomenon of "mutual stimulation of elements", designing and amplifying the synergistic effect between elements, that is, the catalyst effect. In this paper, the topological analysis framework of the dotted-line relationship of physical space is introduced, and it is found that the topology of the catalyst effect has distinct characteristics. This is a minor innovation in the understanding of urban catalyst theory. A case of urban catalyst theory illustrates a full process of transforming the elements that produce the catalyst effect from "grand-centered structure" to "polycentric structure" to "distributed structure". Starting from the classic case, this paper reproduces and further shows the occurrence process of the catalyst effect from the perspective of topology, and uses more cases to show the design of different types of catalyst effects, providing new ideas and references for future design on catalyst effects for different situations.