Design and practice of underground space development of existing historical buildings in soft soils

A three-storey basement has been newly constructed underneath a century-old historical building in Shanghai, which is close to a cultural protection building at three sides. In view of various difficult factors encountered such as the protection requirements, the soft soil foundation, the working space and other factors, a complete development strategy for underground space is adopted. By reciprocatively translating the historical buildings together with excavating downwards, the overall development of the underground space of large masonry buildings and the protection of historical buildings are realized. The strip foundations of the building are reinforced using low-clearance anchor static pressure piles and polyester grouting to reduce building settlement during construction. Based on the successful implementation of the project, new challenges, key techniques and their effects with regard to underground space development underneath existing cultural protection and historical buildings in soft soils are presented.