DSI – Ductile Iron Micropiles International Society for Micropiles London, May 2009 Florian Stützel, DSI-TS
Agenda Introduction Production Installation Load capacity Summary Video
Agenda Introduction Production Installation Load capacity Summary Video
Introduction Driven tube Ductile cast iron
Agenda Introduction Production Installation Load capacity Summary Video
Agenda Introduction Production Installation Load capacity Summary Video
Production Centrifugal casting
Production Heat treatment Transformation grey ductile cast iron
Agenda Introduction Production Installation Load capacity Summary Video
Agenda Introduction Production Installation Load capacity Summary Video
Installation Pile head Soft soil Medium dense gravel Dense sand Soft soil Loose sand Rock Pile shoe Pile tube Coupler concrete Drive & grout = skin friction Dry driven = end bearing
Installation - Endbearing piles Usually non-grouted Driven until a certain set-criteria is fulfilled (e.g. progress < 20 mm / minute) If grouted piles are driven to that set, then the pile is basically an endbearing pile with additional load bearing capacity from skin friction
Installation - Endbearing piles Foot for end bearing piles
Installation - Endbearing piles
Installation Friction piles Simultaneously driven & grouted Driven into a layer of “good” soil Steady control and monitoring of driving progress required
Friction piles
Installation - Friction piles
Agenda Introduction Production Installation Load capacity Summary Video
Agenda Introduction Production Installation Load capacity Summary Video
Load capacity End bearing piles are driven to set e.g. progress less than 20mm / minute Skin friction piles can be stopped before full set
Load capacity - Friction piles 1 st information: soil-expertise
Load capacity - Friction piles 2 nd information: penetration test with DPH
Load capacity - Friction piles 3 rd information: Actual driving record
Load capacity - Friction piles Comparison
Load capacity - Friction piles Driving stopped after 6 m protrusion in a layer, where the driving time exceeded 30secs / 1m 6m x 0.63m²/m x 150 kN/m² = 570 kN
Load capacity - Friction piles Pile test
Load capacity - Friction piles Pile test load / time load / displacement - curve Vertical displacement [mm] Load [kN]
Agenda Introduction Production Installation Load capacity Summary Video
Agenda Introduction Production Installation Load capacity Summary Video
Summary Installation by excavator Suitable for restricted area No break down of pile head Installation into difficult ground condition No wastage of pile section Easy & fast
DSI – Ductile Iron Micropiles International Society for Micropiles London, May 2009 Florian Stützel, DSI-TS