Drilled shaft foundations as well as retaining walls such as tangent and secant pile walls typically have a verticality requirement as part of the specifications. These requirements ensure that the moments and stresses in the shaft are consistent with the design, and in the case of the retaining walls, ensure that there are no gaps in the wall. Ben White and Patrick Hannigan have a nice article in the latest Pile Dynamics newsletter describing the verticality recommendations/requirements from several different entities around the world and also explaining the capabilities of their SHAPE® instrument. You can subscribe to future Pile Dynamics newsletters here.
