UNDERGROUND INFRASTRUCTURE MODELING
Underground modeling is used to support the beams and floors in a building while a column or wall is removed.Excavation shoring is a positive support system that fully stabilizes the ground for an indefinite period. There are three basic configurations for pile type shoring: cantilever, braced and box. Soil nailing is a technique in which soil slopes, excavations or retaining walls are reinforced by the insertion of relatively slender elements – normally steel reinforcing bars. The bars are usually installed into a pre-drilled hole and then grouted into place or drilled and grouted simultaneously. They are usually installed untensioned at a slight downward inclination.
A rigid or flexible facing (often sprayed concrete) or isolated soil nail heads may be used at the surface. The soldier pile lagging can be timber, steel plates, or concrete panels. The steel shapes can be obtained in yield strengths of 36,000 to 70,000 psi, however there may be difficulty obtaining high strength steel shapes on short notice.
Sheeting and timbering must be designated to minimize any flexing of planks and timbers. This is because masonry is very weak in tension and any slight movement which alters the distribution of stresses will cause the foundation and walls to crack. Spalling of interior plaster may result.