Drilling fluid shafts. Shafts can be installed in wet sands using drilling fluid, with or without casing. This procedure of installing drilled shafts can be used as an alternative to the uncased and cased shafts discussed
Pressure-grouted shafts. A special type of nondisplacement deep foundation is the uncased auger-placed
grout shaft. This shaft is constructed by advancing a continuous-flight, hollow-stem auger to the required depth and filling the hole bored by the concrete grout under pressure as the auger is withdrawn. Careful inspection is required during installation, and shaft continuity should be verified by a combination of load tests and nondestructive testing as described later.