Large Diameter and Deep Shafts: Unique Design and Construction Challenges

摘要

Over the past five to ten years, there has been an increasing number of underground infrastructure projects worldwide using different geometries incorporating large diameter, deep shafts into their configuration. Example projects Ch2m Inc. has direct design and construction experience with include shafts for:Blue Plains Dewatering shafts (one of five shafts) for District of Columbia Water and Sewer Authority CSO Clean Rivers Project in Washington DCMatanza-Riachuelo Catchment Sanitation Program; La Plata River Outfall.The design, construction and critical instrumentation monitoring of such shafts brings unique challenges. These challenges can be dealt with in a number of ways, including the use of 3D structural models with a better understanding of soil structure interaction incorporated into the analyses of all loads on the shafts, with resulting savings in material and more flexibility in construction sequencing. The authors draw upon their global experience of design and construction of these large diameter and deep shafts to identify some key unique challenges, and to suggest particular ways in which they can be overcome during design and/or construction.