Design and Construction of Drilled Shafts

An excellent subsurface investigation is necessary. Good construction techniques are needed, as well as proper inspection. The shear strength of the supporting soil is reduced during construction. Small shafts cannot be constructed successfully. Soil movements during construction are minimized. Exposed soil during construction verifies previous subsurface investigations. The size of the shaft may be adjusted. Drilled shafts can be built rapidly, as compared with other types. Pile caps may be eliminated on many jobs, leading to appreciable economy. Construction noise is tolerable as compared to other types of construction of deep foundations. A good subsurface investigation is important to obtain engineering properties of the soil for design computations and selecting the construction procedure.