Rex Klentzman, PEDirector of Engineering

URETEK USA

AcknowledgementsRichard L. Boudreau, PEJohn P. Donahue, PE (Missouri DOT)Randall W. Brown, PhD, PE (URETEK USA)

1979 1988 2000 2003 2006 201820102009

Deep Injection Patented

URETEK’s DeepInjection Processpatent is issued, aprocess to increasethe load bearingcapacity of weak soilsat individual depthsthrough polymerinjection.

1979 1988 2003 2018Exclusive rights in U.S.

URETEK USA, Inc., isgranted the exclusivelicense rights for sales andinstallment of product andservices in the U.S. andMexico.

URETEK patentsthe polyurethane grouting process

URETEK advancesequipment technology oftotal proportion andinjection control ofpolyurethane and patentsThe URETEK Method™ (U.S.Patent No. 4,567,708).

Chapter in progress...

URETEK’s story continuesas our business growthand value are at an alltime high. New materialsand solution offerings toclients to be unveiled laterthis year.

Who is URETEK

• Leader in Geotechnical, Structural Polymer Application

• 29 years experience, with well over 100,000 projects.

Our Clients:

• Over 40 DOT’s (Dept. of Transportation), many with annual contracts

• US Air Force and US Navy - Servicing Airfields

• International & Local Airports• Cities, Counties, private entities.

DeepInjectionURETEK

Increasing subgrade stiffness

CHARACTERISTICS OF POLYURETHANE

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• 2-components: Resin and Hardener (1:1 by volume).• Exothermic chemical reaction causes expansion of the

polymer and creates pressure on the surrounding soils.• Rigid structural polyurethane created as the material

cures. No shrinkage during curing. • 4 to 10 pounds per cubic foot. Strength varies with

density.• Reaction complete in less than 1 minute. Can support

traffic after 20 minutes. Full strength in 24 hours.• Formulated to expel water and resist future intrusion.

URETEK DEEP INJECTION

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• Polymer is surgically placed into the underlying soils via an injection tube where stabilization is needed.

• Multiple injection tubes are used to promote full coverage throughout the area being stabilized.

• Pavement is continuously monitored at the surface throughout the injection process.

• High-density, low-viscosity polyurethane characterized by rapid expansion and large volume increase created by chemical reaction between the components.

SOIL & POLYMER INTERACTION

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• Governed by both soil and polymer properties• Can be further impacted by adjusting operational

parameters, such as heat and injection pressure• Soil properties: density, grain size, permeability,

and degree of saturation• Polymer properties: chemical composition and

viscosity• Operational parameters: injection temperature,

injection pressure, shot duration, and shot sequencing

PROCESS

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• Problem identified and defined.• Soil analysis provided via DCP/Core testing.• Available drawings and engineering reports analyzed,

along with visual inspection of surrounding area.• Engineered solution developed and injection plan

created.• Stabilization and pavement lifting achieved by controlled

polymer injections at varying depths. • Soil stabilization confirmed by movement at the surface.• If needed, verification with pre and post FWD testing.

URETEKdeepInjection

soil box injectiondemo

URETEKdeepInjection

soil box injectiondemo

Laboratory ResearchURETEK Deep Injection Process

Strength Increase

Graded Aggregate Base• 700% 57 stone• 1,000%Natural sand • 7,000%

Laboratory ResearchURETEK Deep Injection Process

Repeated Load Permanent Deformation Test (NCHRP Report No. 598)

• Polyurethane injection promotes a very high resistance to strains.

* These strains often produce pavement distresses such as rutting (flexible pavements) and faulting (rigid pavements).

Rex Klentzman, PEDirector of Engineering

URETEK USA

AcknowledgementsRichard L. Boudreau, PEJohn P. Donahue, PE (Missouri DOT)Randall W. Brown, PhD, PE (URETEK USA)

Problem Description

• May 18, 2011

• US 65 is a two-lane asphalt highway with gravel shoulders

• Vertical re-alignment: a hump along the roadway alignment was lowered 5 ft. to provide better visibility

Problem Description• Base: 10 – 12 inches (25 –

30cm) of reclaimed asphalt with crushed stone placed over the cut

• Subgrade in problem area is the fill material from the cut

3.75-in asphalt concrete

10-12 inches reclaimed base

~5 ‘ fill

Problem Description• Proposed pavement cross

section

Asphalt not installed

Subgrade

Problem Description• Paving operations were

stopped when the base exhibited 2-inch (5cm) ruts and finger-width cracks

• Emergency stabilization of subbase needed to open the road in time for Memorial Day 2011

Problem Description• Paving operations were

stopped when the base exhibited 2-inch (5cm) ruts and finger-width cracks

• Emergency stabilization of subbase needed to open the road in time for Memorial Day 2011

Preliminary Evaluation• Missouri DOT mobilizes

their FWD to site

Preliminary Evaluation• Center plate deformations below 20

mils (0.020 in.) were deemed – by design computations – to be acceptable for pavement construction on top of reclaimed base layer

Preliminary Evaluation• An approximate 650-foot (200m)

length of alignment exhibited excessive deformation – some in excess of 100 mils (0.1 in.)

Preliminary Evaluation• An approximate 650-

foot (200m) length of alignment exhibited excessive deformation – some in excess of 100 mils (0.1 in.)

Subsurface Investigation

• Coring through 10 to 12-inch (25 – 30cm) reclaimed base layer to expose subgrade soils coring assembly

• Dynamic cone penetrometer testing with depth to identify potential weak zones. 5 locations selected based on FWD results

Subsurface Investigation

• Soft zone of soil identified at 3-5 foot (1-1.5m)depths(blow counts < 9, several below 5)

Subsurface Investigation

• Soft zone of soil identified at 3-5 foot (1-1.5m)depths(blow counts < 9, several below 5)

Subsurface Investigation

The Solution• Polyurethane Grouting

• Enters the soil as a low-viscosity liquid

• 2-component: Resin & Hardener (1:1 by volume)

• Hydro Insensitive - Formulated to resist water intrusion into the reaction

The Solution• Polymer cures rapidly

• Reaction complete in < 1 minute

• Can support traffic after 20 minutes

The Solution• Polymer installation

• 5/8” injection tubing set to injection depth

The Solution• Polymer is placed via an

injection tube; “surgically” placed in the strata where stabilization is needed

• Multiple injection tubes are used to promote full coverage throughout the area being stabilized

The Solution• Polymer cures rapidly

• Expansive reaction expels excess water from soil

Results• After 5 Years

still inserviceand increased stiffness

Summary• Duration of ‘Special’ Project: evaluation through

construction completion -- 12 calendar days –reopening roadway before a busy holiday weekend

• Improvements achieved:

• 60 percent improvement in foundation support following injections

• Additional improvements gained 5 years following injections (suspected to be due to long-term dissipation of pore pressures)

Thank you!..Questions ?

Rex Klentzman, PEDirector of EngineeringURETEK USA

AcknowledgementsRichard L. Boudreau, PEJohn P. Donahue, PE (Missouri DOT)Randall W. Brown, PhD, PE (URETEK USA)