Permanent Secant Pile Cut-Off Wall
for UIHC Children’s Hospital (CH) &
Parking Ramp No. 2 (HPR2)
Iowa City, IA
Schnabel Foundation Company
By: Mark Goudschaal, P.E.
Presentation Overview
Owner/Project Team & Summary of
Work – Overall Plan and Facts.
2. Secant Pile Section and Soil Profile
3. Secant Pile Wall Procedures and
Installation.
4. Perm. Wall Const.
5. Conclusion
1.
Project Team
Owner:
University of Iowa
Hospitals and Clinics
(UIHC)
Construction Manager:
Gilbane Construction
Company (GCC)
Excavation/Sitework
Contractor:
Peterson Contracting,
Inc. (PCI)
SPW Contractor:
Schnabel Foundation
Company (SFC)
DP Contractor:
Veit Companies
Architect/Engineer: Carl
Walker, Inc. (HPR2) &
Heery Design (CH) &
Shive Hattery
Geotechnical Engineer:
Terracon
Existing Site – Prior to Construction
Bid Package Plan/Work Sequencing
Children’s Hospital & HPR2 Plan
CH Temporary ERS – HPR2 S. SPW
Children’s Hospital & Parking Ramp
Soil Boring Locations
UIHC CH & HPR2 Soil Borings
SPW & ERS PLAN
Existing Caissons
Typical Section
Typical SPW Section
Ex. Parking Ramp Caisson Obstruction
Secant Pile Walls (SPW)
Definition: SPW are formed by installing
overlapping piles to form a water cut-off.
1. First install primary piles.
2. Then install secondary piles within the
gaps and set reinforcing steel.
3. The difference in pile diameter and
spacing determines the actual overlap.
Secant Piles:
Hydraulic
Piling Rig –
Bauer BG28
Secant Pile Wall
(SPW) - Plan and
Verticality
Tolerances are
critical.
BG28
Install SPW Templates
Installed Circular Foam Template
South SPW & Cap – Children’s
SPW Drill Primary (Unreinforced) First
Concrete, f’c=3,000psi for Primary & Secondary Piles.
Secant Piles Hard-Hard Shafts
HPR2 Drill More Primary Holes
Secondary Holes – Pile Installation
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Finish Secondary Piles
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Casing Shoes and Tooling Repairs
New Casing teeth
High Torque Rotary Casing
Thick walled sections of temporary
flush-joint steel casings (2 – 5 meter
lengths) with cutting teeth on starter
casing shoe.
 Used with high torque rotary piling
equipment and/or casing oscillator.
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Oscillator Pulling Casing
Flush-Joint Casing – Conical Bolts
Placing Concrete & Pile
Drilling and Setting Pile
Crane Mat Access Road
SPW Tie Connections
Drilling 2nd Tier Permanent
Tiebacks
Drilling Tiebacks – Using Uncoiler
Automated Grout Plant
Automated High Volume Grout Station
Finished SPW - October 2013
Current HPR2 & Childrens Hospital
CH- April 2014 – Looking North
ANY QUESTIONS/COMMENTS?