withdrawable tube 



ililil 



voids or cavities 



expendable helical 

 drilling point 



pile 



withdrawable tube 



expendable helical 

 drilling point 



Step 1 : drill and screw in tube 



Step 2: insert pile 



pile 



withdrawable tube 



IpilPIijJ IS® 



backfill material 

 or grout 



expendable helical 

 1 drilling point 



Step 3: pour in backfill materials or grout 

 and compact while removing tube 



Step 4: installed pile 



Figure 35. Conceptual drawing of drilled and screwed pile. 



80 



