1. Real Estate Management Strategy and Underpinning
Indications
Timing
Methods of underpinning
IWM 2003 Seattle Jouko Lehtonen

2. IWM 2003 Seattle Jouko Lehtonen
Need of underpinning
Existing foundations on wooden piles
Settlements
Potential risks of decayed wooden piles
Cracking of superstructures
IWM 2003 Seattle Jouko Lehtonen

3. Economy of underpinning
Earlier stage in renovation construction
(i) => less settlements
(ii) bigger collection of potential underpinning methods and less problems in superstructures => less costs
Later working => financing can be done later
Optimal date for underpinning?
IWM 2003 Seattle Jouko Lehtonen

4. Methods of underpinning in very soft soils
Jet grouting
Applicable only up to 10 m column length
Micropiling
Applicable to any pile length
Various pile types up to foundation conditions
Impact driven micropiles
Conventional driving against the pile head
Side Grip Piling
Jacked micropiles
Conventional pushing against the pile head
Side Grip Installation
Drilled micropiles
DTH
Top Hammer Installation
Side Grip Installation?
IWM 2003 Seattle Jouko Lehtonen

5. Micropiling method has impact to the building and use of it
Settlements during construction
Noise
Timing
Some methods are available only in the earlier stages of the potential underpinning time
IWM 2003 Seattle Jouko Lehtonen

6. IWM 2003 Seattle Jouko Lehtonen
Decision to underpin
Today: no policy to follow => decisions made by chance or by accident
Tomorrow?
Tools for strategic planning
Collection of underpinning methods
=> decisions will be made based on good understanding on the problems and challenges
=> less costs, less damages in superstructures
=> more business to the micropile industry
=> win-win
IWM 2003 Seattle Jouko Lehtonen