With rapid infrastructure construction and urban redevelopment, there has been an increasing demand for utilisation of underground spaces, which gives rise to a large number of excavation projects. In the past decade, a series of new trends have emerged on excavation engineering in Shanghai, China. As available ground resources in congested urban areas are scarce, excavations become much larger and deeper than before. More excavations have to be carried out in close proximity to existing buildings, tunnels, utilities and other structures. Any severe damages to the nearby utilities probably lead to economic losses and complicated conflicts among owners, tenants, utility customers and the public. As a consequence, it is of great concern not only to ensure the safety of the excavation itself but also to mitigate adverse excavation-induced influences on the adjacent environment. This paper presents recent developments in practical design and construction techniques of controlling excavation-induced deformations in Shanghai. Commonly used techniques including the top-down construction method, ground improvement, the zoned excavation method and the underpinning technique are described and discussed. Relevant instrumented case histories on excavations in different types of urban environment are reported as well.
Wang, W. D., Li, Q., & Xu, Z. H. (2018). Design and construction of deep excavations in Shanghai, China. Geotechnical Research, 5(3), 143–161. https://doi.org/10.1680/jgere.18.00007