Integrated and holistic knowledge map of resilient modulus studies for pavement materials: A scientometric analysis and bibliometric review of research frontiers and prospects

Since the establishment of the American Association of State Highway and Transportation Officials (AASHTO) in 1960, the design of pavement structures has improved tremendously. The characterization of pavement materials has gained significant popularity all around the world. Throughout several decades, researchers have conducted extensive research in material characterization and unanimously agree that resilient modulus (MR) is one of the prime factors in predicting the pavement layers' performance. This study aims to systematically analyze and visualize the status of research conducted on pavement material. The analysis was performed based on the web of science by investigating the existing research undertaken to date on the MR of pavement materials using VOSvieweer and CiteSpace tools. This study examined two keywords, “resilient modulus” and their frequency of occurrence using the function of keyword co-occurrence analysis. The search result successfully recognized three clusters utilizing the process of cluster analysis based on a total of 1810 documents that contained “resilient modulus” in the title, abstract, or keywords. The study explored the growth pattern in the field of MR by using citation bursts analysis to reveal how research related to pavement materials has evolved during time. This study is unique as it provides the reader with detailed information on the existing literature related to MR studies to better classify the status quo and uptrend in pavement materials. In addition, future research topics related to the MR characterization were highlighted.