Abstract: The installation curve of contact rail expansion joint is an important document to guide the installation of expansion joint in urban rail transit engineering. Its rationality directly affects the normal use and maintenance of contact rail in the operation stage of the line. Compared to the underground contact rail system, the expansion of the elevated contact rail system is not only affected by the temperature change of the rail itself, but also by the external factors of the viaduct. Through research of the expansion and contraction condition of the anchor section of the elevated contact rail system, correction suggestions are given for the installation curve of the contact rail expansion joint in the elevated section, which can provide reference for the installation of the contact rail expansion joint in the elevated section of the project.