Abstract:
As available space in urban centers becomes scarcer, builders and developers are increasingly turning to vacant or under-utilized existing structures to meet their growing needs. The re-purposing of these structures often requires support of the existing structure and additional new foundations to support higher loads from additional features added. This presentation is a case history of two projects that were recognized in 2020 and 2021 for the design and construction of micropile foundations to meet the needs of these projects. Challenges for the projects included underpinning the existing building, foundations to support new structures, and support of extensive excavations. Site access and limited headroom conditions under the existing facility also needed to be addressed. The presentation will include a review of the existing structures, the local subsurface conditions, micropile installation and performance testing, and laod trasnfer from the existing foundations to the new underpinning and support system.