Abstract: In order to study the soil fracturing grouting pressure under asymmetric loads, based on the cavity expansion theory and unified strength theory and considering the influence of the asymmetric loads, the analytical solutions of stress fields and displacement fields in the plastic regions surrounding slurry bubble, as well as the radius of plastic region and limit expansion pressure are deduced. The solutions are validated through the engineering example. The results show that grouting pressure considering the symmetrical load is larger than that considering the asymmetric loads, which indicates that the radius of plastic region are underestimated in the analysis of grouting under the symmetrical load. For the cylindrical cavity expansion and the spherical cavity expansion, where K0 is less than 1, the starting fracturing pressure increases with the increment of K0; while the radius of plastic region significantly decreases with the increment of K0. Where K0 is greater than 1, the starting fracturing pressure decreases with the increment of K0, but the change of radius of plastic region is limited. Therefore it is important to estimate the initial stress conditions of the soil previously before the critical fracturing pressure. The results will improve theoretical basis for design and construction of fracturing grouting.

Key words: slurry bubble expansion, fracturing grouting, asymmetric load, grouting pressure, radius of plastic region