Proceedings - 13th International Workshop on Micropiles - 2017, Vancouver, BC, Canada, (ISM, DFI, ADSC)
Micropiles Counter Unbalanced Loading During Partial Building Demolition
Helen Robinson, P.E. and Nate Dumas, P.E., Schnabel Engineering, Donna Adams, P.E., Dunbar Milby Williams Pittman and Vaughan
Richmond Pavilion. The existing building consisted of two full floors below grade with one floor above grade on the south side and four floors above grade on the north side. As part of the proposed construction of the new Pavilion, the southern portion of the existing Pavilion was demolished and replaced with a new structure with four belowgrade levels. This demolition and excavation resulted in unbalanced lateral earth pressures on the remaining portions of the building, and affected the structure’s wind and seismic resistance. In addition, the portion of remaining structure adjacent to the new excavation would need to be underpinned to prevent instability to the 2 additional below grade floors. To remedy this condition, a system of concrete shear walls and buttresses were constructed inside the existing building to provide the required building bracing for lateral loads. A network of tiebacks and micropiles was conceived to provide the necessary lateral and vertical support during demolition and excavation. This paper discusses the rationale for selection of this system and describes the general design procedure followed, which involved tight collaboration between the structural and geotechnical engineer. Construction and quality control are also discussed.
|article #2638; publication #1033 (ISM- 2017)|