Sacramento City Hall
City: Sacramento
State: CA
Owner: City Of Sacramento
General Contractor: Hensel Phelps
Project Description:
The construction of the new Sacramento City Hall required an excavation up to 21-ft deep in soft and loose silty, sandy soil. The shoring was required to protect streets on three sides and the existing City Hall on the fourth side. Schnabel Foundation Company designed and constructed a soldier beam shoring system with tiebacks and both shotcrete and timber lagging. The piles were vibrated in and the tiebacks cased as necessary.
Upon completion of the shoring system, Schnabel installed 32 micropiles inside the existing City Hall. The micropiles were required as part of a seismic retrofit of the existing structure. The micropiles were installed in a low overhead condition and drilled to a depth of 65 lf. The design load in compression was up to 188 kips. A pre-production test pile was tested in compression to a maximum test load of 375 kips.
