Study on Reinforcement of Tunnel Loose Sand Layer by Grouting

This paper studies the application of grouting reinforcement technology in the reinforcement of sand layer in tunnel and underground engineering. The influence of different factors on the unconfined compressive strength of solid sand was studied by orthogonal horizontal test, combined with physical properties of cement slurry and water content of sand layer. The test results show that the water content of sand, cement water cement ratio and curing time have significant effects on the strength of solid sand, and the curing time has the greatest effect. Finally, the optimal slurry ratio was determined as 8% sand water content, 28 days curing time and 0.8 water-cement ratio. Under this ratio, the strength of the solid sand body was the best, and the gel time and viscosity of the slurry also met the engineering requirements. This study provides an important reference for grouting reinforcement engineering under similar geological conditions.