EireChch
Geotechnical
- Jul 25, 2012
- 1,343
Hi,
I am a graduate Civil Engineer working in Christchurch, New Zealand.
I am working on a report presenting suitable foundation options for a proposed house.
The floor level has a minimum height of 2.8 m above sea level to meet flood plane regulations thus resulting in a height approximately 1.5 m above existing ground level.
These foundation options have to be in line with Department of building and housing guidelines.
I have done a liquefaction analysis of two dynamic probe results and came up with 127 - 129 mm settlement in ULS design case (0.35g/7.5 magnitude).
Most of the settlement is in the upper 6 m of material.
My two possible options are
Deep piles extending to 9 m depth. Assuming pile embedmant of 1 m and the 1.5 above existing ground level the pile will be approx 11.5 m long. The piles will support a concrete slab
Deep soil mixing to approx 6 m. with 1.5 m of imported fill on top to bring the house to the required level. Resulting in a 7.5 m capping layer of non liquefiable material. Then proceed with a concrete slab on top
I just wanted to see what peoples opinions where on these options and what other considerations i should be thinking of
Cheers
Eirechch
I am a graduate Civil Engineer working in Christchurch, New Zealand.
I am working on a report presenting suitable foundation options for a proposed house.
The floor level has a minimum height of 2.8 m above sea level to meet flood plane regulations thus resulting in a height approximately 1.5 m above existing ground level.
These foundation options have to be in line with Department of building and housing guidelines.
I have done a liquefaction analysis of two dynamic probe results and came up with 127 - 129 mm settlement in ULS design case (0.35g/7.5 magnitude).
Most of the settlement is in the upper 6 m of material.
My two possible options are
Deep piles extending to 9 m depth. Assuming pile embedmant of 1 m and the 1.5 above existing ground level the pile will be approx 11.5 m long. The piles will support a concrete slab
Deep soil mixing to approx 6 m. with 1.5 m of imported fill on top to bring the house to the required level. Resulting in a 7.5 m capping layer of non liquefiable material. Then proceed with a concrete slab on top
I just wanted to see what peoples opinions where on these options and what other considerations i should be thinking of
Cheers
Eirechch