Abstract: This study addresses the Guangzhou Metro Line 11 access line II shield project in sand-rock stratum. Constructing the upper shield-stacked tunnel faced significant challenges. These challenges included ground settlement, a small clear distance, and crossing over an existing tunnel with shallow overburden.To ensure construction safety and address these challenges, this research explored key construction technologies. These technologies are suitable for complex sand-rock stratum. The study considered multiple factors. These factors were the shield machine type, equipment status, surrounding environment, geological conditions, and operational safety.Three key technologies were developed and analyzed. These technologies are the pile-raft cover plate technique (replacing subgrade), the matrix reinforcement control technique, and the dynamic control technique for tunneling parameters. The research employed theoretical analysis, numerical simulation, and field tests. Key technologies suitable for constructing the upper shield-stacked tunnel in sand-rock stratum were summarized.Results demonstrated the effectiveness of the technologies. Ground settlement and deformation of the existing tunnel were controlled within allowable limits. The construction process was safe and reliable. The technical outcomes were satisfactory.These technologies provide an effective solution for similar shield-stacked tunnel projects in sand-rock stratum. They offer high potential for wider application. They serve as a valuable reference for future similar projects.