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

1. 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

Project Team

Owner:

University of Iowa Hospitals and Clinics

(UIHC)

Excavation/SiteworkContractor:

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

Construction Manager:

Gilbane Construction Company (GCC)

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

BG28

Secant Pile Wall (SPW) - Plan and Verticality Tolerances are critical.

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

I I I I I

Finish Secondary Piles

I I I I I I I I I

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.

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?