Deterioration of Concrete Roads

2

Concrete Roads

• Joint Spalling

• Punch outs

• Cracking

• Faulting

• Slab failures

• Riding Quality

Models From USA Chile

3

• Absolute (Concrete HDM-4)Predicts the future condition

CONDITION = f(a0, a1, a2)Limited to conditions model developed forProblems with calibration

• Incremental (Asphalt HDM-4)Predicts the change in condition from the current

condition: CONDITION = f(a0, a1, a2)

Can use any start point so much more flexible

Types of Deterministic Models

4

Surface types upon which the concrete RD models are based

Surface type Description

JP Jointed Plain concrete pavement - without load transfer dowels

JP Jointed Plain concrete pavement - with load transfer dowels

JR Jointed Reinforced concrete pavement

CR Continuously Reinforced concrete pavement

Concrete Roads Surface Types

5

Joint spacing

3 - 6 m

AggregateInterlock

Slab

Base

Figure 2.1 Jointed plain concrete pavements without dowels

Jointed Plain Concrete Pavement without Dowels

6

Joint spacing

3 - 6 m

Dowels

Figure 2.2 Jointed plain concrete pavements with dowels

Jointed Plain Concrete Pavement with Dowels

7

10 - 20 m

D owelsS lab

B ase

Jo in t spac ing

W e ld e d w i r e f a b r ic ( 0 . 1 – 0 . 2 % )

F i g u r e 2 . 3 J o i n t e d r e i n f o r c e d c o n c r e t e p a v e m e n t s

Jointed Reinforced Concrete Pavement

8

C racks sepa ra tion

S la b

B a se

R e in fo rcem en t s tee l0 ,6 - 0 ,8 % o f a rea

F ig u re 2 .4 C o n tin u o u s ly re in fo rced co n crete p avem en ts

Continuously Reinforced Concrete Pavement

9

Distress modes modelled in HDM-4

No. Distress mode Units of measurement Pavement surface type

1 Cracking Percent of slabs cracked JP

Number per mile JR

2 Faulting inches JP and JR

3 Spalling Percent of spalled joints JP and JR

4 Failures Number per mile CR

5 Serviceability loss Dimensionless JR and CR

6 Roughness Inches per mile (or m/km) JP, JR and CR

Distress Modes

10

• The principal data for predicting the deterioration of concrete pavements: Properties of materials Percentage of reinforcement steel Drainage conditions Load transfer efficiency (across joints, and

between slabs and shoulder) Widened outside lanes

Structural Characteristics

11

• Transverse cracking occur due to high stress levels in the slabs or defects originating from material fatigue

• The stresses are caused by the combined effect of thermal curling, moisture-induced curling and traffic loading

Cracking

12

Transverse Cracking

C DTransv.

Joint

Traffic

A B C D

Distresswidth

Distresswidth

Slab

Shoulder

CLLongitudinal Joint

Transv.Joint

A B

13

• Transverse cracking (% of slabs cracked) is modelled as a function of cumulative fatigue damage in the slabs and:Cumulative ESALsTemperature gradientMaterial propertiesSlab thicknessJoint spacing

Cracking in JP Pavements

14

• The number of deteriorated transverse cracks per km is predicted as a function of:Cumulative ESALsPavement ageSlab thickness and Ec

Percentage of reinforcement steel, PSTEELBase typeClimate/environment (FI, MI)

Cracking in JR Pavements

15

Curling

16

Curling

17

Curling and Traffic Loading

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Curling and Corner Distresses

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• Faulting is caused by the loss of fine material under a slab and the increase in fine material under nearby slabs

• This flow of fine material is called pumping, and is caused by the presence of high levels of free moisture under a slab carrying heavy traffic loading

• The effects of thermal and moisture-induced curling and lack of load transfer between slabs increase pumping

Faulting

20

Faulting

Transv.Joint

TrafficSlab

CLLongitudinal Joint

Transv.Joint

A B

A Bfaulting

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• The average transverse joint faulting is predicted as a function of:Cumulative ESALsSlab thicknessJoint spacing and openingProperties of materialLoad transfer efficiencyClimate/environment (FI, PRECIP, DAYS90)Base typeWidened outside lanes

Faulting

22

Agua

Temperatura + Humedad + Secado de Construcción

Carga en Losa de Aproximación

Movimiento Lento del Agua

Faulting

23

Carga en Losa de Alejamiento

Movimiento Rápido del Agua

INERCIA

IMPULSIONSUCCION

Depósito de Sólidos Base Erosionada

ESCALONAMIENTO

Faulting

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• Transverse joint spalling is the cracking or breaking of the edge of the slab up to a maximum of 0.6 m from the joint.

• Transverse joint spalling can be caused by:

• Presence of incompressible materials

• Disintegration of concrete under high traffic loading

• Improper consolidation of the concrete in the joint

• Wrongly designed or built load transfer system

Spalling

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• Transverse joint spalling is predicted as a function of:Pavement ageJoint spacingType of sealDowel corrosion protectionBase typeClimate/environment (FI, DAYS90)

Spalling

26

Spalling

Shoulder

Traffic

Transv.Joint

Low Sev.:1,8 m

High Sev.:1,5 m

Low Sev.:2 m Moder. Sev.:

2,5 m

A B

C D

A B

Distresswidth

Joint

C D

< 0,6 m

JointCrack

Transv.Joint

Transv.Joint

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Spalling

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• Localised failures include loosening and breaking of reinforcement steel and transverse crack spalling

• These are caused by high tensile stresses induced in the concrete and reinforcement steel by traffic loading and changes in environmental factors

• The number of failures is predicted as a function of: Slab thickness Percentage of reinforcement steel Cumulative ESALs Base type

Failures in CR Pavements

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• This is a subjective user rating of the existing ride quality of a pavement (ranging from 0 extremely poor to 5 extremely good)

• For JR pavements, the change in PSR is calculated as a function of cracking, spalling and faulting

• For CR pavements, the change in PSR is calculated as a function of slab thickness, cumulative ESALs and pavement age

Present Serviceability Index

30

• For JP concrete pavements, roughness is calculated as a function of faulting, spalling and cracking

• For JR and CR concrete pavements, roughness is calculated as a function of PSR

Roughness

31

IRI

• IRIo• Transversal Cracks• Faulting• Spalling

== ff

ESAL

IRI

IRIoIRIo

Roughness on JPCP

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• Modulus of elasticity of concrete, Ec

• Modulus of rupture of concrete, MR28

• Thermal coefficient of concrete, • Drying shrinkage coefficient of concrete, • Poisson’s ratio for concrete,

• Modulus of elasticity of dowel bars, Es

• Modulus of elasticity of bases, Ebase

• Modulus of subgrade reaction, KSTAT

Property of Materials

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Maintenance Works (1)Maintenance works for concrete pavements

Pavement surface typeWorksclass

Works type Works activities

JP JR CR

Routine Routinemaintenance

Vegetation control, line marking, draincleaning, etc.

Load transfer dowels retrofit

Tied concrete shoulders retrofit

Longitudinal edge drains retrofit

Preventivetreatment

Joint sealing

Slab replacement

Full depth repair

Partial depth repair Restoration

Diamond grinding

Bonded concrete overlay Rehabilitation

Unbonded concrete overlay

Periodic

Reconstruction Pavement reconstruction

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Maintenance Works (2)

Maintenance works applicable to JP concrete carriageway

Works type Works activity / operation ID code Ranking Unit cost

Reconstruction Pavement reconstruction REC 1 per m2

Unbonded concrete overlay UOL 2 per m2

RehabilitationBonded concrete overlay BOL 3 per m2

Slab replacement SLR 4 per m2

Partial depth repair PDR 5 per m (joint length)Restoration

Diamond grinding* DGR 6 per m2

Load transfer dowels retrofit* DWL 7 per m (joint length)

Tied concrete shoulders retrofit* TCS 7 per km

Longitudinal edge drains retrofit* RED 7 per km

Preventivetreatment

Joint sealing* SLJ 7 per m (joint length)

Note:

* Works activity can be applied together with slab replacement or partial depth repair in the sameanalysis year

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Maintenance Works (3)

Maintenance works applicable to JR concrete carriageway

Works type Works activity / operation ID code Ranking Unit cost

Reconstruction Pavement reconstruction REC 1 per m2

Unbonded concrete overlay UOL 2 per m2Rehabilitation

Bonded concrete overlay BOL 3 per m2

Full depth repair FDR 4 per m2

RestorationDiamond grinding* DGR 5 per m2

Tied concrete shoulders retrofit* TCS 6 per km

Longitudinal edge drains retrofit* RED 6 per kmPreventivetreatment

Joint sealing* SLJ 6 per m (joint length)

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HDM Series – Volume 4