The interface zone between mortar and aggregate influences overall performance of concrete and is an important issue for concrete research. Focusing on the structure and performance characteristics of the interface zone in cement concrete

the development of interface research in P. R. China and elsewhere were reviewed. The research aspects discussed included interface structure and performance

study techniques

interface improvement methods

and the influence of the interface on overall concrete performance. The influential factors of structural characteristics and interface zone performance

together with both microscopic and macroscopic research techniques

were summarized. The reasons for differences in interface zone structure and performance

and its degree of influence on the overall concrete performance were analyzed. Methods for improving the interface zone were generalized

including using an interface with slag powder as inorganic material and one with an organic coupling agent. Keys to research and future directions were proposed.