Laboratory and Field Evaluation of a Novel Cement Grout Asphalt Composite

The novel cement grout asphalt composite (CGAC) in this study is a new semiflexible composite consisting of open-graded hot mix asphalt (HMA) filled by injecting cement grout materials. The mechanical performance and engineering properties of the composite were evaluated through laboratory tests, including the Marshall stability test, rutting test, three-point bending test, split tensile test, and permeability test. Moreover, field test sections were constructed, and the laboratory test results and in situ results were compared. The results showed that, after grouting, the performance of composite materials was further enhanced, especially their high-temperature stability and moisture sensitivity. In fact, no permanent deformation (rutting) occurred, and the tensile strength ratio (TSR) was increased by 18.7%. In situ test applications revealed that compared with manual grouting, mechanized grouting technology had positive influences on field constructability and performance of CGAC regarding Marshall stability and splitting tensile strength. Findings of this study are beneficial to design, construction technology, and pavement maintenance. (C) 2018 American Society of Civil Engineers.