deterioration processes, remaining strength and repair of buried … · buried pipe infrastructure...

Ian Moore, PhD, PEng

Deterioration processes, remaining strength and repair

of buried pipes

Ian Moore, PhD, PEngProfessor and Canada Research Chair

GeoEngineering Centre at Queen’s-RMC

www.geoeng.ca

Buried pipe infrastructure

I. Gravity flow sewers & culverts $1B/year Ontario

Intr

oduc

tion

$1B/year OntarioII. Water supply pipes

$1B/year OntarioIII. Gas & other

Most investment (>80%) nowon repair & replacement of existing systems

Cast iron pipe, Hamilton ON

Vitrified clay pipe, Toronto ON

Intr

oduc

tion

Objectives

A. Soil-pipe interaction and design of rigid and flexible pipes

B. Deterioration and remaining strength

Intr

oduc

tion

B. Deterioration and remaining strength- rigid sewer pipes & culverts- corrugated metal pipes

C. Repair using liners- cured in place liners (gravity & pressure pipes)- grouted slip-liners (gravity flow pipes)- spray-on liners (gravity flow pipes)

Intr

oduc

tion

A. Soil-pipe interaction

Composite behaviour: combined influence of soil and pipe on loads and load resistance.I. Role of soil and pipe stiffness

pipe

inte

ract

ion

- Rigid pipes- Flexible pipes

II. Design of new pipeIII. Backfill properties

(constrained modulus MS)

A. S

oil-

pipe

inte

ract

ion

I. Role of soil and pipe stiffness

• Uniform earth pressure component produces hoopforce or radial contraction

pipe

inte

ract

ion

force or radial contraction

• Nonuniform earth pressuresproduce bending moment (rigid pipes) or ovaling(flexible pipes)

A. S

oil-

pipe

inte

ract

ion

I. Role of soil and pipe stiffness• Transition from rigid (high moment, low deflection)

to flexible pipe (low moment, high deflection) controlled by ratio of soil modulus MS to EpIp

pipe

inte

ract

ion

sf IE

RMS

3

=

A. S

oil-

pipe

inte

ract

ion

ppf IE

80%

90%

100%

moment displacement

I. Role of soil and pipe stiffnessTransition from rigid (high moment, low deflection) to flexible pipe (low moment, high deflection) controlled by ratio of soil modulus MS to EpIp

pipe

inte

ract

ion

flexi

ble

0%

10%

20%

30%

40%

50%

60%

70%

80%

0.1 1.0 10.0 100.0 1000.0

displacement

A. S

oil-

pipe

inte

ract

ion

pp

sf IE

RMS

3

=

M/M

rigid

or

∆∆ ∆∆Dv/

∆∆ ∆∆Dv f

lexi

ble

Elastic soil-pipe interaction theory (Hoeg, 1968)

II. Design approachesRigid Pipe (pipe>>soil):consider moment M & thrust Nneglect ∆Dv

M(BF,S )

pipe

inte

ract

ion

90%100%

flexi

ble

M(BF,Sf)N(Sf)sincepipe still>>soil

A. S

oil-

pipe

inte

ract

ion

0%10%20%30%40%50%60%70%80%90%

0.1 1.0 10.0 100.0 1000.0

moment displacement

pp

sf IE

RMS

3

=

M/M

rigid

or

∆∆ ∆∆Dv/

∆∆ ∆∆Dv f

lexi

ble

II. Design approachesRigid Pipe (pipe>>soil):Bedding factor BF=MTEB/Mburied

pipe

inte

ract

ion Wv

Three Edge Bearing test

versus

accounts for distribution of soil support, not MS or Sf

A. S

oil-

pipe

inte

ract

ion

Pair of invert forces W v/2

90%100%

II. Design approachesRigid Pipe (pipe>>soil): Flexible pipe (soil>>pipe)consider moment & thrust neglect moment Mneglect ∆Dv consider thrust N & ∆Dv

pipe

inte

ract

ion

flexi

ble

0%10%20%30%40%50%60%70%80%90%

0.1 1.0 10.0 100.0 1000.0

moment displacement Ignore ConsiderMs since ∆Dv (Ms)

N(Sf)soil still

>>soil >> pipe

Ny(pipe),Nbuck(EpIp,Ms)

A. S

oil-

pipe

inte

ract

ion

pp

sf IE

RMS

3

=

M/M

rigid

or

∆∆ ∆∆Dv/

∆∆ ∆∆Dv f

lexi

ble

90%100%

II. Design approachesRigid Pipe (pipe>>soil): Flexible pipe (soil>>pipe)R/C and clay pipe Corrugated steel pipe

Presentation ignoressemi-rigid pipes

pipe

inte

ract

ion

flexi

ble

0%10%20%30%40%50%60%70%80%90%

0.1 1.0 10.0 100.0 1000.0

moment displacement

Ignore

A. S

oil-

pipe

inte

ract

ion

pp

sf IE

RMS

3

=

M/M

rigid

or

∆∆ ∆∆Dv/

∆∆ ∆∆Dv f

lexi

ble

III. Soil propertiesCharacteristics of intact backfill (Ms) well established

by Selig and McGrath (now in AASHTO, AWWA)

pipe

inte

ract

ion

Vertical stress level kPaSoil type RD 7 35 70 140 275 410SW (SP, GW, GP)Granular

85 3.2 3.6 3.9 4.5 5.7 6.990 8.8 10.3 11.2 12.4 14.5 17.2

Three soil types at three densities (% Proctor)Effect of stress levels (burial depth)

A. S

oil-

pipe

inte

ract

ion

Granularmaterials

90 8.8 10.3 11.2 12.4 14.5 17.295 13.8 17.9 20.7 23.8 29.3 34.5

MLSilty backfill

85 2.5 2.7 2.8 3.0 3.5 4.190 4.6 5.1 5.2 5.4 6.2 7.195 9.8 11.5 12.2 13.0 14.4 15.9

CLClay soils

85 0.9 1.2 1.4 1.6 2.0 2.490 1.8 2.2 2.4 2.7 3.2 3.695 3.7 4.3 4.8 5.1 5.6 6.2

B. Deterioration and remaining strength

I. Rigid sewers and culvertsII. Flexible metal storm sewers & culverts

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

I. Rigid sewer pipes

• Clay pipes fractureand deform

• Vitrified clay (glass) isvery durable

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

very durable• What are the causes

of clay sewer and R/C pipe failures?

Vitrified clay pipe, Toronto ON

Clay pipes, Ephesus, Turkey

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Likely mechanism:

I. Rigid sewer pipesB

. Det

erio

ratio

n an

d re

mai

ning

str

engt

hB

. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

Likely mechanism:i Joint leakage – ingress of

groundwater or outflow


. Det

erio

ratio

n an

d re

mai

ning

str

engt

hB

. Det

erio

ratio

n an

d re

mai

ning

str

engt

h


groundwater or outflowii Erosion of backfill


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

ii Erosion of backfill

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth


groundwater or outflowii Erosion of backfill


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

ii Erosion of backfilliii Less uniform soil support

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth


groundwaterii Erosion of backfill


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

ii Erosion of backfilliii Less uniform soil supportiv Moments increase as

Bedding Factor reduces (loads more nonuniform); fracture & accelerated erosion

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Invert erosion

U.K. Tests: invert voids fill with soil from the springline


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

with soil from the springline so springline voids again form

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Gumbel, J., Spasojevic, A., and Mair, R. 2003, Cent rifuge modelling of soil load transfer to flexible sewer liners, Proceedings ASCE Pipeline 2003 Conference, Baltimore, 11 pp.


Voids Contact Angles:

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Angles:

0o (no void)

30o

60o

90oB. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

255075

100125150175200225250

Perc

enta

ge C

hang

e of

Str

esse

s (%

)

%Moment change with void growth


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

-250-225-200-175-150-125-100-75-50-25

025

0 25 50 75 100

Angle of Voids ( )

Perc

enta

ge C

hang

e of

Str

esse

s (%

)

%

Tan and Moore (2007)Voids Contact Angles

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

255075

100125150175200225250

Perc

enta

ge C

hang

e of

Str

esse

s (%

)

Moment tripled

Moment doubled

Interface friction

& Void width


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

-250-225-200-175-150-125-100-75-50-25

025

0 25 50 75 100

Angle of Voids ( )

Perc

enta

ge C

hang

e of

Str

esse

s (%

)

%

Tan and Moore (2007)

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Voids Contact Angles


Remaining “strength”

Fractured pipe behaves as flexible pipeStructurally stable unless:

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Structurally stable unless:- Soil erosion continues- Segments come loose

→ rehabilitate to preventthese developments

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth


Concrete pipe deterioration - sulfuric acidattack (sewer gas) – concrete lost from crown to waterline

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

MacDougall (2012)


Concrete pipe Concrete loss has littledeterioration effect on moment capacity

at the crown unlessthe steel corrodes

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

the steel corrodes

Loss of springlinemoment capacity not usually critical

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

MacDougall (2012)

10.0

100.0∆D/D0.2%

0.5%SW95

I. Rigid sewer pipesSoil modulus controls flexible pipe deflection

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

0.1

1.0

10.0

1 10

Ms

MP

a 1% 2%

5%

10%

SW90

SW85

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

∆∆∆∆DH /D=

Moore (2008)

depth (m)

10.0

100.0∆D/D0.2%

0.5%SW95

I. Rigid sewer pipesDesign modulus to estimate new pipe ∆D/D

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

1.2%

0.1

1.0

10.0

1 10

Ms

MP

a 1% 2%

5%

10%

SW90

SW85

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

∆∆∆∆DH /D=

Moore (2008)

depth (m)

1.2%

e.g. 4min SW90

10.0

100.0∆D/D0.2%

0.5%SW95

I. Rigid sewer pipesEstimate ∆D/D using CCTV for “effective” Ms

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

1.2%

0.1

1.0

10.0

1 10

Ms

MP

a 1% 2%

5%

10%

SW90

SW85

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

∆∆∆∆DH /D=

Moore (2008)

depth (m)

1.2%

observe 10%

(8x larger)

infer1.6MPa

I. Rigid sewer pipesFurther finite element analysis to estimatehow erosion changesdeflectionsCalculate soil damage

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Calculate soil damageindex for sands & clay

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

erodedH

designH

designS

effectiveS

D

D

M

MSDI

,

,

,

,

∆∆

==

Tan & Moore (2006), Moore (2008)


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

6

7

8

9

10

disp

lace

men

t mul

tiplie

r =

SD

I -1

fine grained backfill

αααα

finebackfill

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Moore (2008)1

2

3

4

5

6

0 30 60 90void angle α (degrees)

disp

lace

men

t mul

tiplie

r =

SD

I

granular backfill

SDI coarsebackfill


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

6

7

8

9

10

disp

lace

men

t mul

tiplie

r =

SD

I -1

fine grained backfill

αααα

finebackfille.g. 8x

for SW

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Moore (2008)1

2

3

4

5

6

0 30 60 90void angle α (degrees)

disp

lace

men

t mul

tiplie

r =

SD

I

granular backfill

SDI coarsebackfill

infer≈90o void

I. Rigid sewer pipesCONCLUSIONS1. Originally designed for moment 2. Fractures as a result of soil erosion

(leaking joints) which increases moments

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

(leaking joints) which increases moments3. Sewer gas leads to concrete loss but little

change in capacity until steel corrodes4. Fractured pipe becomes flexible – should

stabilize to prevent further soil erosion5. Infer effective soil modulus or size of

erosion void using ∆Dh,CCTV/∆Dh,design

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

II. Corrugated steel pipes

• Many deteriorated steel pipes across Canada (hundreds of thousands)

• Original design life was 25 to 50 years

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

Metal culvert,

Hwy 401, ON

Corrosion results in

perforations and this leads to erosion

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

II. Corrugated steel pipes

Finite element analysis considering steel loss across invert

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

1

90o Invert Corrosion H=3.0m D=2m135o Invert Corrosion H=3.0m D=2m180o Invert Corrosion H=3.0m D=2m90o Invert Corrosion H=3.0m D=4m135o Invert Corrosion H=3.0m D=4m180o Invert Corrosion H=3.0m D=4m

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

0

0.2

0.4

0.6

0.8

1

0255075100

% t left

FO

SY C

orro

ded

/ F

OS

Y In

tact

180o Invert Corrosion H=3.0m D=4m90o Invert Corrosion H=3.0m D=6m135o Invert Corrosion H=3.0m D=6m180o Invert Corrosion H=3.0m D=6m90o Invert Corrosion H=1.5m D=4m135o Invert Corrosion H=1.5m D=4m180o Invert Corrosion H=1.5m D=4m90o Invert Corrosion H=10m D=4m135o Invert Corrosion H=10m D=4m180o Invert Corrosion H=10m D=4m

135o180o90o

El Taher and Moore (2008)

II. Corrugated steel pipesB

. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

1

90o Invert Corrosion H=3.0m D=2m135o Invert Corrosion H=3.0m D=2m180o Invert Corrosion H=3.0m D=2m90o Invert Corrosion H=3.0m D=4m135o Invert Corrosion H=3.0m D=4m180o Invert Corrosion H=3.0m D=4m

Finite element analysis considering steel loss across invert – little change in thrust so stability against yield decreases linearly with

wall loss

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

0

0.2

0.4

0.6

0.8

1

0255075100

% t left

FO

SY C

orro

ded

/ F

OS

Y In

tact

180o Invert Corrosion H=3.0m D=4m90o Invert Corrosion H=3.0m D=6m135o Invert Corrosion H=3.0m D=6m180o Invert Corrosion H=3.0m D=6m90o Invert Corrosion H=1.5m D=4m135o Invert Corrosion H=1.5m D=4m180o Invert Corrosion H=1.5m D=4m90o Invert Corrosion H=10m D=4m135o Invert Corrosion H=10m D=4m180o Invert Corrosion H=10m D=4m


Different corrosion angles, culvert diameters and burial depths

wall loss

1


. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

Finite element analysis of buckling strength change with corrosion – little change untilcorrosion is substantial

0

0.2

0.4

0.6

0.8

1

0255075100

% t left

Ncr

,FE

A C

orro

ded

/ N

cr,F

EA

Inta

ct

90o Invert Corrosion H=3.0m D=4m135o Invert Corrosion H=3.0m D=4m180o Invert Corrosion H=3.0m D=4m

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth



. Det

erio

ratio

n an

d re

mai

ning

str

engt

h

Finite element analysis of buckling strength- erosion can destabilise the culvert

and the overlying pavement

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

El Taher (2008)

Erosion only

with haunch corrosionwith springline corrosion

II. Corrugated steel pipesCONCLUSIONS1. Original design considers thrust2. Corrosion reduces stability against yield

linearly with respect to wall loss

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

linearly with respect to wall loss3. Erosion can dramatically reduce buckling

strength and lead to instability4. Erosion can also compromise the

overlying pavement5. Culvert repair to stabilize soil and pipe

B. D

eter

iora

tion

and

rem

aini

ng s

tren

gth

C. Repair using Liners

I. Lining procedures- Sewers and culverts- Water pipes

C. R

epai

r us

ing

liner

s

II. Design considerations- Cast in place liners within gravity flow pipes- Slip-liners within gravity flow pipes- Rigid (& semi-rigid) spray on liners within

gravity flow pipes

C. R

epai

r us

ing

liner

s

Slip-liningC

. Rep

air

usin

g lin

ers

Use any preformed pipe (metal, polymer, …)Grout the space between pipes

HDPE pipe slip-lining of corrugated steel pipe, nea r Kaladar, ON

C. R

epai

r us

ing

liner

s

Cured-in-place lining - sewersC

. Rep

air

usin

g lin

ers

• Felt impregnated with epoxy or other resin• Hot water, steam, or UV light cured• Circular prismatic shapes easy; also non-circular and

variable diameter liners (special expertise needed)

Repaired sewer line Toronto, ON

C. R

epai

r us

ing

liner

s

Prepare service connections(locate and plug)Insert resin impregnated liner

Cure with hotwater

Cured in place lining - pressure pipeC

. Rep

air

usin

g lin

ers

water

Liner of excess length so wavesdevelop – these control strength

Technology trialHamilton ON, 2004

Strength testingQueen’s, 2008

C. R

epai

r us

ing

liner

s

120” CMP CulvertPanel Lok IIIE

Strip-wound liningC

. Rep

air

usin

g lin

ers

Panel Lok IIIE

Polymer strips welded,glued or locked togetherGrout or reversewind to treat gap

Courtesy Danby

www.dot.ca.gov

C. R

epai

r us

ing

liner

s

Courtesy Danby

Spray on linersC

. Rep

air

usin

g lin

ers

- Stiff (structural) Portland cement liner sprayed within corrugated steel and reinforced concrete culverts and sewers (CO)

- Flexible polymer sprays also used to seal leaks (e.g. joints)

1.2m corrugated steel pipe from 407ETR

Pipe after repair using GeoTree liner

C. R

epai

r us

ing

liner

s

Deform-reform liningFold and form lining & Swage lining

www.dot.ca.gov

C. R

epai

r us

ing

liner

s

Thermoplastic tube folded, pulled into place,then opened out, or squeezed through cone.

www.dot.ca.gov

www.ultraliner.com

C. R

epai

r us

ing

liner

s

II. Design considerations

Geotechnical aspects of liners in gravity flow pipes

• Cured in place liners• Slip liners

C. R

epai

r us

ing

liner

s

• Slip liners• Sprayed liners• Discussion of F1216.C

. Rep

air

usin

g lin

ers

Two potential demands (loads)

i. Will external fluid loads reach the liner?

Cured in place liners

ExternalPressure

C. R

epai

r us

ing

liner

s

loads reach the liner?

How?Grout pressure (construction)Groundwater through fractures

FracturedHost Pipe

FlexibleLiner

C. R

epai

r us

ing

liner

s

Two potential demands (loads)

ii. External earth loads

• overburden pressure FlexibleEarth Load

C. R

epai

r us

ing

liner

sCured in place liners

• overburden pressurechanges after lining

• vehicle loads DamagedCulvert

FlexibleLiner

C. R

epai

r us

ing

liner

s

ExternalPressure

FracturedHost Pipe

FlexibleLiner

Resistance

i. If external fluid reaches the liner,

C. R

epai

r us

ing

liner


reaches the liner, how will it fail?

> Controlled by buckling strength (nonlinear so depends on imperfections!)

C. R

epai

r us

ing

liner

s

El Sawy and Moore (1996, 1997, 1998), Moore (2005)

Resistance

ii. If external earth and vehicle loads reach

C. R

epai

r us

ing

liner


vehicle loads reach the pipe, how will itfail?

> Local bending where vertical

diameter decreases after repair

C. R

epai

r us

ing

liner

s

Law and Moore (2004, 2007)

C. R

epai

r us

ing

liner

s

0.8%

1.0%Laboratory MeasurementsFinite Element AnalysisRing under Parallel Plate Load

Parallel plate loading model

Cured in place linersC

. Rep

air

usin

g lin

ers

Vertical Liner Deformation (mm)

0 2 4 6 8 10 12 14 16

Cir

cum

fere

ntia

l Str

ain

-1.0%

-0.8%

-0.6%

-0.4%

-0.2%

0.0%

0.2%

0.4%

0.6%


Bending strain in liner

C. R

epai

r us

ing

liner

s

allowlinerhostpipeH

D

t

OD

t

D

D εε <−∆−= ))(2

1)((3.4max

Cured in place liners

- Sets a limit on maximum allowable liner thickness since deflection is imposed by the soil- Higher tensions than if designed as direct buried polymer pipe!

C. R

epai

r us

ing

liner

s

allowlinerhostpipeliner DODD

εε <−−= ))(1)((3.4max


C. R

epai

r us

ing

liner


25%

30%

35%

40%

max

imum

thic

knes

s t/

Dlin

er%

7.5%

5%

3.5%

2%

0.5% 1%

C. R

epai

r us

ing

liner

s

Moore (2008)

0%

5%

10%

15%

20%

0% 2% 4% 6% 8% 10%

allowable strain

max

imum

thic

knes

s t/

D

∆DV/Dliner=20%

10%

1.3% strain limit7.5% deflection

Exhumed liner samples (12 in

total).

• ASTM standard for cured in place liners• Considers liner buckling using empirical

‘enhancement factor’ K=7 (Insituform liner)• K=7 incorrectly used for many liners (may

Use of F1216C

. Rep

air

usin

g lin

ers

Liner inflation and curing using hot water

total).• K=7 incorrectly used for many liners (may be <4 for thermoplastic liners!)

• Uses pipe supported by spring model to define buckling strength under earth load

• However, earth load buckling not possible since the old sewer carries thrusts, and the spring model is also poor

C. R

epai

r us

ing

liner

s


total).

• To seal joints & prevent leakage & erosion• No established design method available• Need to consider joint movements• Saiyar, Moore & Take (2010) gives

Polymer spraysC

. Rep

air

usin

g lin

ers


total).• Saiyar, Moore & Take (2010) gives estimate of rotation as a function of the ground movements

• Becerril & Moore(2013ab),Yu & Moore(2013) & Moore et al. (2012) give joint response to surface and earth loads

C. R

epai

r us

ing

liner

s


total).

1. 407 ETR project examining spray-on-liner• Strength evaluation and design procedure

for selection of wall thickness – completion in July 2013

Current projectsC

. Rep

air

usin

g lin

ers


total).in July 20132. NCHRP 14-19 for US DOTs • Guide for assessment of deteriorated

culverts and sewers and their repair• Develop designs for slip & cured in place

liners – completion in December 2013

C. R

epai

r us

ing

liner

s

Damaged pipe tests before and after repair

C. R

epai

r us

ing

liner

sSlip-liners

C. R

epai

r us

ing

liner

s

Simpson, Hoult and Moore (2013)

- Research on low strength and high strength grouts

- Q: Is the liner a permanent form for the grout, or does it form part of the long

C. R

epai

r us

ing

liner

sSlip-liners

grout, or does it form part of the long term structural system?

- Q: Is there full or partial composite action (what are the interactions between soil-old pipe-grout-liner?)

- Q: Effect of a grout-filled void?

C. R

epai

r us

ing

liner

s

Mai, Hoult and Moore (2012), Simpson, Hoult and Moo re (2013)

Damaged pipe tests before and after repair

C. R

epai

r us

ing

liner

sSlip-liners

C. R

epai

r us

ing

liner

s

Simpson, Hoult and Moore (2013)

C. Repair using linersCONCLUSIONS1. There are many existing lining methods &

new procedures continue to be developed2. Design of cured in place liners well

C. R

epai

r us

ing

liner

s

2. Design of cured in place liners well established, but earth load effects need re-evaluation to consider local bending(continue to use F1216 earth load buckling until code changes, to avoid liability)

3. Rational design method for slip liners considering interactions being developed

C. R

epai

r us

ing

liner

s

C. Repair using linersCONCLUSIONS4. Design for buckling using ASTM F1216 &

K=7 OK for CIP thermosetting liners but often inappropriate for other liner products

C. R

epai

r us

ing

liner

s

5. Not necessarily conservative to design liner as direct burial pipe – ignores interactions between liner and old

6. Erosion effects (voids) also being examined though further work needed

C. R

epai

r us

ing

liner

s

Acknowledgements

• Natural Sciences and Engineering Research Council (NSERC), Canada Foundation for Innovation, Province of Ontario

• NSERC, 407ETR, MTO, Cities of Hamilton and • NSERC, 407ETR, MTO, Cities of Hamilton and London, US Academy of Sciences

• Collaborator Drs Neil Hoult & Andy Take• Current and former students David Becerril

Garcia, Mohamed El Taher, Michael Law, Van Mai, Bryan Simpson, Masoumeh Saiyar, & Zheng Tan.

Publications (see www.geoeng.ca)

• Becerri Garcia & Moore 2013 Transportation Research record (to appear)• Becerri Garcia & Moore 2013 Journal of Geotechnical and Geoenvir. Eng (to appear)• Law & Moore 2007 Tunneling and Underground Space Technology,22(5) 655–665.• Law & Moore 2003 North American No Dig, Las Vegas, NV.• Moore & El-Sawy 1996 Transportation Research Record 1541, 127-132• El Sawy & Moore 1997 Annual conf. Pipeline Division, ASCE, Boston, pp. 416-423• El-Sawy & Moore 1998 Journal of Structural Engineering, ASCE, 124(11), 1350-1357• El Taher, M. and Moore, I.D. 2008. Transportation Research Record, 2050, 157-166• El Taher, M. and Moore, I.D. 2008. Transportation Research Record, 2050, 157-166• Mai, Hoult, & Moore 2012. North American NoDig 2012, Orlando, Paper A-4-03.• Moore 2005. Buried Infrastructure Repair Using Liners: Construction Techniques,

Struct. & Geotech. Issues, 11th Int.Symposium, Cairo, Egypt, May• Moore, Becerril Garcia, Sezen & Sheldon, 2012, NCHRP Web only document 190.• Simpson, Hoult & Moore 2013 North American NoDig 2013, Sacramento, CA• Saiyar, Moore & Take 2010. Int. No-Dig 2010, ISTT Singapore, paper 43, 7pp. • Tan & Moore 2007. Transportatn Research Board Ann.Conf., Washington D.C. 29pp• Wang & Moore 2013. Journal of Geotechnical and Geoenvir. Eng (to appear)

Ian Moore, PhD, PEng

Deterioration processes, remaining strength and repair

of buried pipes

Ian Moore, PhD, PEngProfessor and Canada Research Chair

GeoEngineering Centre at Queen’s-RMC

www.geoeng.ca

deterioration processes, remaining strength and repair of buried … · buried pipe infrastructure...

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