Support Under Distress
By Jasper Calcara | February 25, 2016
The 6.0 magnitude Napa Earthquake struck on August 24, 2014, and caused substantial damage to many structures in this popular tourist destination. DHC received many calls during the aftermath of the earthquake, as the damage was widespread and structures were in need of temporary support. Bracing and shoring was deemed necessary for many building simply to allow personnel to gain access, retrieve belongings, or survey the true extent of the destruction.
One building that was hit particularly hard was the Historic Napa Courthouse located downtown on Brown Street. D.H. Charles Engineering, Inc. was contracted to develop a wall bracing system that could be installed without positive anchorage to the wall itself. This was imperative, as the competence of the wall was unknown and workers could not be exposed to a potential collapse during bracing installation. The resulting system consisted of vertical I-beams that were rotated upwards against the wall, and then diagonally braced with tilt-up braces anchored to the wood floor joists. This scheme and installation process provided the necessary safe working environment, and ultimately allowed for temporary scaffold towers to be placed inside the room which provided temporary support to the roof.
DHC was also contacted by RMB Management Company to come up with a solution to recover personal items for customers of the heavily damaged two-story self-storage building at the Napa Self Storage facility. The entire second story had shifted out of alignment from its foundation such that the first story walls were heavily skewed and damaged. The primary challenge was not being able to visibly see the full extent of the damage without first stabilizing the whole building and providing safe access to the structure.
Our first step was to design an exterior bracing system at the second floor, for global stabilization, and relieve load to the damaged interior walls. We then designed an extensive plan to incrementally provide internal access to the lower floor units. Modular scaffold shoring would be used throughout the building’s access points to simultaneously shore the lower level while providing safe entry for workers to evaluate the extent of the damage, recover personal belongings, and provide additional shoring within the storage units as necessary to stabilize the structure.
DHC enjoyed the opportunity to support their neighbors in a time of need, and help the residents and businesses of Napa return to normal life.