Slurry and Technology Optimization for Grouting Fissures in Earthen Sites with Quicklime

Abstract

Shrinkage differentiation and the need for multiple replenishments of slurry after fissure reinforcement are key problems for the grouting reinforcement of fissures in earthen sites. In this study, quicklime was mixed with 1.5% SH binder, clay, and fly ash in different proportions to prepare nine different mixtures and water-cement ratios of SH-(CaO + C + F) slurry. An expansibility test was performed, and based on the results, four groups of slurry were selected for a fluidity test. Ultimately, three different water-cement ratios were considered, and the mixing ratio of 3 : 2 : 5 was determined to produce the optimum slurry. The curing age was optimized according to the intensity and tensile and flexural strengths of the concretion. The selected slurry and curing age were then applied to testing traditional grouting technology and optimized grouting technology (i.e., microlime piles in the fissure) in fissure grouting field experiments. The acoustic wave, penetration resistance, and infrared thermal imaging results after fissure grouting were used to develop a preliminary explanation for the related mechanisms of slurry swelling, hardening, and lime pile compaction. The results showed that the combination of the preferred slurry and optimized grouting technology help address the problems of shrinkage differentiation on both sides of the fissure and need for multiple replenishments of the slurry after grouting.