Deterioration of Concrete Roads
Concrete Roads
•
•
•
•
•
•
Joint Spalling
Punch outs
Cracking
Faulting
Slab failures
Riding Quality
Models From
 USA
 Chile
2
Types of Deterministic Models
• Absolute (Concrete HDM-4)
 Predicts
the future condition
CONDITION = f(a0, a1, a2)
 Limited
to conditions model developed for
 Problems 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
3
Concrete Roads Surface Types
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
4
Jointed Plain Concrete Pavement
without Dowels
Joint spacing
3 - 6 m
Aggregate
Interlock
Slab
Base
Figure 2.1 Jointed plain concrete pavements without dowels
5
Jointed Plain Concrete Pavement
with Dowels
Joint spacing
3 - 6 m
Dowels
Figure 2.2 Jointed plain concrete pavements with dowels
6
Jointed Reinforced Concrete
Pavement
Joint spacing
10 - 20 m
Slab
Dowels
Base
Welded wire fabric (0.1 – 0.2%)
Figure 2.3 Jointed reinforced concrete pavements
7
Continuously Reinforced Concrete
Pavement
Cracks separation
Slab
Base
Reinforcement steel
0,6 - 0,8 % of area
Figure 2.4 Continuously reinforced concrete pavements
8
Distress Modes
Distress modes modelled in HDM-4
No.
1
Distress mode
Cracking
Units of measurement
Pavement surface type
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
9
Structural Characteristics
•
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

10
Cracking
•
•
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
11
Transverse Cracking
Distress
width
Distress
width
A
D
C
B
Longitudinal Joint
C
D
Transv.
Joint
Transv.
Joint
A
B
Slab
Shoulder
12
Traffic
C
L
Cracking in JP Pavements
•
Transverse cracking (% of slabs cracked) is
modelled as a function of cumulative fatigue
damage in the slabs and:
 Cumulative ESALs
 Temperature gradient
 Material properties
 Slab thickness
 Joint spacing
13
Cracking in JR Pavements
•
The number of deteriorated transverse
cracks per km is predicted as a function of:
 Cumulative ESALs
 Pavement age
 Slab thickness and Ec
 Percentage of reinforcement steel,
PSTEEL
 Base type
 Climate/environment (FI, MI)
14
Curling
15
Curling
16
Curling and Traffic Loading
17
Curling and Corner Distresses
18
Faulting
•
•
•
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
19
Faulting
A
faulting
B
Longitudinal Joint
Transv.
Joint
Transv.
Joint
A
B
Traffic
Slab
20
C
L
Faulting
•
The average transverse joint faulting is
predicted as a function of:
 Cumulative ESALs
 Slab thickness
 Joint spacing and opening
 Properties of material
 Load transfer efficiency
 Climate/environment (FI, PRECIP, DAYS90)
 Base type
 Widened outside lanes
21
Faulting
Temperatura + Humedad + Secado de Construcción
Agua
Carga en Losa
de Aproximación
Movimiento Lento del Agua
22
Faulting
23
Spalling
•
•
•
•
•
•
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
24
Spalling
•
Transverse joint spalling is predicted as a
function of:
 Pavement age
 Joint spacing
 Type of seal
 Dowel corrosion protection
 Base type
 Climate/environment (FI, DAYS90)
25
Spalling
< 0,6 m
Distress
width
D
C
B
A
Crack
Joint
Joint
Low Sev.:
1,8 m
Low Sev.:
2m
High Sev.:
1,5 m
A
Transv.
Joint
Transv.
Joint
Transv.
Joint
C
D
Moder. Sev.:
2,5 m
Traffic
B
Shoulder
26
Spalling
27
Failures in CR Pavements
•
•
•
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
28
Present Serviceability Index
•
•
•
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
29
Roughness
•
•
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
30
Roughness on JPCP
=
f
IRI
IRI
• IRIo
• Transversal Cracks
• Faulting
• Spalling
IRIo
ESAL
31
Property of Materials
•
•
•
•
•
•
•
•
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
32
Maintenance Works (1)
Maintenance works for concrete pavements
Works
class
Routine
Works type
Works activities
Pavement surface type
JP
Routine
maintenance
Preventive
treatment
Periodic
Vegetation control, line marking, drain
cleaning, etc.

Load transfer dowels retrofit

Tied concrete shoulders retrofit


Longitudinal edge drains retrofit


Joint sealing


Slab replacement



Full depth repair
Restoration
CR


Partial depth repair

Diamond grinding


Bonded concrete overlay



Unbonded concrete overlay



Pavement reconstruction



Rehabilitation
Reconstruction
JR
33
Maintenance Works (2)
Maintenance works applicable to JP concrete carriageway
Works type
Reconstruction
Works activity / operation
ID code
Ranking
Unit cost
Pavement reconstruction
REC
1
per m
2
Unbonded concrete overlay
UOL
2
per m
2
Bonded concrete overlay
BOL
3
per m
2
Slab replacement
SLR
4
per m
2
Partial depth repair
PDR
5
per m (joint length)
Diamond grinding*
DGR
6
per m
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
Joint sealing*
SLJ
7
per m (joint length)
Rehabilitation
Restoration
Preventive
treatment
2
Note:
*
Works activity can be applied together with slab replacement or partial depth repair in the same
analysis year
34
Maintenance Works (3)
Maintenance works applicable to JR concrete carriageway
Works type
Works activity / operation
ID code
Ranking
Unit cost
2
Reconstruction
Pavement reconstruction
REC
1
per m
Rehabilitation
Unbonded concrete overlay
UOL
2
per m
Bonded concrete overlay
BOL
3
per m
Full depth repair
FDR
4
per m
Diamond grinding*
DGR
5
per m
Tied concrete shoulders retrofit*
TCS
6
per km
Longitudinal edge drains retrofit*
RED
6
per km
Joint sealing*
SLJ
6
per m (joint length)
Restoration
Preventive
treatment
35
2
2
2
2
HDM Series – Volume 4
36