Grouting uplift for structural rectification of a high-rise building

Under poor stratum conditions, buildings are particularly susceptible to uneven settlement, which constitutes a significant threat to structural safety. Foundation grouting uplift is generally recognized as an effective method for addressing such issues. This study proposes a novel grouting uplift technology, aiming to overcome some of the deficiencies existing in traditional grouting uplift methods. The technology proposed in this study employs a special high-aluminum iron composite slurry as the grouting material and applies a construction strategy of low-pressure and slow grouting in different areas. For strata with voids, a staged grouting uplift technology (first reinforcement and then uplift) is further formulated to ensure the stability of the strata and the safety of the structure. During the grouting uplift process, automatic monitoring equipment is equipped for real-time monitoring. This technology has been successfully applied to the building settlement control project in Mengshan County, Guangxi, China, achieving excellent results: after the grouting construction was completed, the tilt of the building was reduced from 6‰ to 0.3‰, meeting the requirements for normal use and habitation. During the research process, a detailed geological investigation was first conducted on the site where the building was located. Based on the data obtained from the investigation, a numerical simulation was carried out using the finite difference software FLAC3D, which identified the cavities in the strata as the cause of the uneven settlement of the building and their impact on the building structure. Based on the results of numerical simulation, the feasibility of the grouting uplift construction was analyzed, and a detailed construction plan was formulated. Finally, based on the field monitoring data after construction, the application effect of this new grouting lifting technology was evaluated, and its future development direction was discussed.