Abstract:Based on the slurry shield engineering of Xinjizhou water supply corridor project in Nanjing Yangtze River. The applicability of reusing waste sand as shield synchronous grouting materials was studied, which was produced by slurry shield construction in silty fine sand layer and rock stratum. Through changing the particle size distribution of abandoned sand in sandy soil layer, the influence of particle size distribution of sand layer waste sand on the performance of mortar was examined; furthermore, the influence of the particle shape of rock stratum waste sand on the mortar performance was investigated, and the proportioning optimizing of synchronous mortar prepared from rock stratum waste sand was discussed. The results indicated that the sand layer waste sand can be used to replace the original sand directly, and the rock stratum waste sand can also satisfy the engineering requirements by adjusting the proportion; The fluidity of mortar improves with the increase of fineness modulus and sand content of sand layer waste sand, but excessive clay content results in worse fluidity, shorter setting time and lower strength of mortar; The rougher the surface of rock stratum waste sand particles, the worse the fluidity and shorter the setting time of mortar. The waste sand of shield construction can be used for synchronous grouting under the appropriate proportioning, but the mortar proportioning should be adjusted appropriately with the change of particle size distribution and particle surface shape of waste sand. The research results have engineering reference value for the proportioning adjustment and optimization of synchronous grouting materials prepared from shield waste sand.