Bearing capacity characteristics of grouted screw piles

Environmental awareness leads to an increasing use of screw piles in construction because such piles generate low noise, low vibration and also generate no surplus soil. Also, such piling technique has practical benefi t during construction. Such piles are also believed to provide relatively large compressive strength and pullout resistance capacity. In this study, a new kind of ground improving pile is developed wherein the surrounding soil around the pile is also improved by injecting compressed cement grout using non-return valves. Such piles provide larger resistance capacity than conventional screw piles. The ground is improved by injecting grout into the ground in three patterns. The improvement effect and bearing capacity characteristics of each pattern was compared and examined through fi eld tests (plate loading test).