Project: lasix eye

CASE STUDY

Project:
Geotechnical Engineer:
Structural Engineer:
Contractor: Pinnacle


Job Description:

Renovation of this existing commercial space from a retail outlet
to a Laser Eye Clinic, necessitated formation of a larger mezzanine
floor supported on pilings, through an existing main floor structural
slab, as the remainder of the building is pile supported.
Access was to be made through commercial entryway to the
existing store and 30-35 foot long pilings were placed inside the
building using a custom designed hydraulic auger head and drill
platform. Head height was limited to 8-9 feet in piled areas and pile
capacity was between 15,000-60,000lbs (67.5 – 270kN).
Soils:

Soils were found to be fills comprised of blacktop sections, large
stumps and concrete debris mixed with granular fills. Depth
to adequate undisturbed bearing ground of dense sands
and gravels was 25-30 feet.
Repair:

HELICAL PULLDOWN™ Micropiles were selected due to smaller
and lightweight equipment that could operate off the existing floor
slab and access the building through the existing entry doors
to the store. Yet the piles are capable of high capacities.
Piles were SS5 square shaft anchors embedded in a 6 inch microsil
fiber reinforced grout column. Lead section of pile shaft was 6-8-10
inch triple helical assembly, also initially pulling
a 6”displacement disc with a 10’ long 6” diameter PVC sleeve
into position. Through that sleeve, the remainder of the column
was screwed down to target soils of adequate capacity.
Installation torques over the terminal three feet of insertion
reached 5500 ft/ lbs
Control of piling insertion was done as is typical, through use
of continuous torque monitoring during pile insertion and direct
measurement of grout volumes placed into the sleeve during
the process. Geotechnical engineering, overseeing and pile
certification was performed by: Matt Kokan P.E. of Geopacific
Consultants of Burnaby, B.C.
Production Piling and Installation:
All production pilings were installed using the same procedures as
outlined above, each in turn. The grout mix used was a proprietary
silica fume grout, manufactured by Baselite Concrete Industries of
Vancouver, B.C., for Vickars Developments. It is known as
Pulldown Pile grout Type A. The grout is mixed on site and
reinforced with polyfibers and added to the pvc sleeve as he pile is
being fomed during installation.
Pile installation equipment as pictured is a custom built portable
piling rig powered by a portable hydraulic pump with hydraulic
differential pressure gauges registering input hydraulic pressures
and therefore installation torques. The apparatus is controlled using
a foot pedal for insertion or retrieval of screw anchors or pilings. It
requires 72” of headroom and 30” minimum doorway width
of access.
Hand held units for interior works have similar capacity. However they can be carried in sections
and snapped together in restricted areas. That feature allows use in such tight spaces as, closets,
small bathrooms and crawlspaces.

Source: http://www.vickars.com/pdf/Lasixcentre.pdf