Scott Anderson "Asset Performance Management"

Report
Risk-Based Asset and Performance
Management: A Geotechnical Perspective
Scott A. Anderson
FHWA - Resource Center
Risk-Based Asset and Performance
Management
 Can’t do all we would like
Need to Optimize
 Can’t do it all at once
Need to Prioritize
This is the motivation for
“management”
There is also a catalyst
Catalysts for management
 Bridge – safety
 Pavement – cost
 Geotechnical – performance
MAP-21 National Performance Goals
1.
2.
3.
4.
5.
6.
7.
Safety
Infrastructure Conditions: State of Good Repair
Congestion Reduction
System Reliability- improve efficiency
Freight Movement and Economic Vitality
Environmental Sustainability
Reduced Project Delivery Delays
4
FAQ on MAP-21
•
•
•
Question 2: What requirements does MAP-21 have pertaining to
asset management?
Answer 2: Each State is required to develop a risk-based asset
management plan for the National Highway System (NHS) to improve
or preserve the condition of the assets and the performance of the
system. (23 U.S.C. 119(e)(1), MAP-21 § 1106)
The Secretary is required to issue a regulation not later than 18
months after date of enactment, after consultation with the States,
which will establish the process to develop the State asset
management plan for the NHS. (23 U.S.C. § 119(e)(8), MAP-21 §
1106)
Source: FHWA website
5
•
•
•
Question 3: What are the scope and content of a risk-based asset
management plan?
Answer 3: In general, a State risk-based asset management plan
includes strategies that lead to a program of projects that would make
progress toward achievement of the State targets for asset condition
and performance of the NHS in accordance with 23 U.S.C. 150(d)
and supporting progress toward the achievement of the national goals
identified in 23 U.S.C. 150(b). (23 U.S.C. 119(e)(2), MAP-21 § 1106)
States must address pavements and bridges but are encouraged
to include all infrastructure assets within the highway right-of-way in
their risk-based asset management plan.
23 U.S.C. 119(e)(4) (MAP-21 § 1106) requires that a State asset
management plan be in a form that the Secretary determines to be
appropriate. It also requires that the plan include:
1.
2.
3.
4.
5.
6.
a summary listing of the pavement and bridge assets on the NHS in the State, including a
description of the condition of those assets;
asset management objectives and measures;
performance gap identification;
lifecycle cost and risk management analysis;
a financial plan; and
investment strategies.
6
•
•
Question 4: What other infrastructure assets within the highway
right-of-way can be included in a risk-based asset management
plan?
Answer 4: While the MAP-21 risk-based asset management plan
specifies pavements and bridges on the NHS in 23 U.S.C. § 119(e)(4),
23 U.S.C. 119(e)(3) (MAP-21 § 1106) requires the Secretary to
encourage States to include all infrastructure assets within the
highway right-of-way. Examples of such infrastructure assets include:
pavement markings, culverts, guardrail, signs, traffic signals,
lighting, Intelligent Transportation Systems (ITS) infrastructure,
rest areas, etc., in the asset management plan.
1.
2.
Really?
3.
4.
5.
6.
7.
Safety
Infrastructure Conditions: State of Good
Repair
Congestion Reduction
System Reliability- improve efficiency
Freight Movement and Economic Vitality
Environmental Sustainability
Reduced Project Delivery Delays
7
Geotechnical Impacts on System Performance
Though the pavement and bridges are in
excellent condition, the performance here is
poor.
The Geotechnical Role
 We can address many performance goals
 The intent of the law may fail if we don’t manage
our assets to support performance goals
 The language we speak will become less relevant
if we aren’t ‘managing our assets’
 We are responsible for certain links in a
transportation corridor
(The System)
Asset management
Performance management
Risk-based
Asset management
Risk-based
Performance management
Some Practical Definitions
1. Asset Management
2. Performance Management
3. Geotechnical Asset

Next slides
11
Physical assets along a corridor
12
Independent features, not elements of others
13
Comprised of earth or performance
achieved through earth interaction with
structure or inclusion
14
Proposed Geotechnical Asset Taxonomy – 1/8/14
Rock
Slope
The adjective “Geotechnical” means the asset is comprised of earth, pertains to
earth, or its performance is achieved through earth interaction with a structure
or inclusion.
Inclusions are any and all non-earth modifications: pipes, anchors,
grids, fabrics, grouts, etc.
Soil
Modified
Rock
Embankment
Soil
Modified
Independent
Feature
Rock
Subgrade
Soil
Modified
ROW
Feature
Earth Retaining
Structure
Corridor
and/or
GAM
Section
Element of
other Structure
Bridge
Element
Tunnel
Element
Stabilized
Earth
Steel or
Reinforced
Concrete
Predominant distinction in how
feature is managed. Features
with inclusions are “modified”.
Pavement
Element
Physical
Asset
OutsideROW
Feature
Water
bodies
NonCorridor
Geotechnical
Asset
Data
NonPhysical
Asset
Equipment
Knowledge
Slopes
Material
Sites
Stockpiles
or other
Established management systems for other structures
that have (or should have) geotechnical elements.
Others, could be added; for example – culverts.
Structures
(walls,
etc.)
High slopes, shorelines, and structures typically owned by
others outside the ROW that are sources of risk because they
can impact performance
Investigation and test results, lab and field equipment, key
personnel
Current Practice
 Implementation in States today
Alabama
North
Carolina
Tennessee
New
Jersey
Indiana
Iowa
California
Alaska
Georgia
South
Carolina
Connecticut
New York
Florida
Washington
D.C.
Maine
Pennsylvania
Kentucky
New
Hampshire
Maryland
Ohio
Michigan
Wisconsin
Colorado
Vermont
Illinois
Minnesota
Kansas
Missouri
Arizona
Washington
Utah
South
Dakota
Oregon
North
Dakota
Nebraska
Montana
Idaho
 They are all taking steps: some
big, some small
Remember the fine print?

23 U.S.C. 119(e)(4) (MAP-21 § 1106) requires that a State asset
management plan be in a form that the Secretary determines to be
appropriate. It also requires that the plan include:
1.
2.
3.
4.
5.
6.
a summary listing of the pavement and bridge assets on the NHS in the State, including a
description of the condition of those assets;
asset management objectives and measures;
performance gap identification;
lifecycle cost and risk management analysis;
a financial plan; and
investment strategies.
 That’s what these states are doing, all in their
own ways.
Let’s look at linking Condition, Performance and Risk Management
- and define “Condition” and “Risk Management” as we do so
Two diversions to show breadth of
the revolution
 Performance Based Practical Design (PBPD)
 SHRP2 - R19B: BRIDGE FOR SERVICE LIFE
BEYOND 100 YEARS: SERVICE LIMIT STATE
DESIGN
…Then on to some new ideas
PBPD – Definition
The PBPD approach:
• grounded in performance management
• exercise engineering judgment to build up the
improvements from existing conditions to
address purpose and need
• uses appropriate performance-analysis tools
• considers both short- and long-term project and
system goals
PBPD – Overlapping
Value
Engineering
Road
Diets
Livability
Context
Sensitive
Solutions
SHRP2 R19B – Bridges for Service Life beyond 100 Years:
Executive Summary
The objectives of SHRP 2 Project R19B were to develop design and detailing guidance and calibrated Service Limit States (SLSs) to provide 100
year life, and to develop a framework for further development of calibrated SLSs. Generally, it has been assumed that maintenance activities will be
sufficient to prevent significant loss of the strength and stiffness that would result in unsatisfactory service level performance.
Consideration of SLSs requires different input data than the previously calibrated Strength Limit State I (ULSs). In ULSs, the limit state function is
defined with two variables, resistance, which was considered constant in time, and loads. For SLSs ,
a different approach is needed:
• As exceeding service limit states does not lead to a clear, immediate, loss of functionality, defining the
resistance is very subjective.
• Acceptable performance can be subjective (full life-cycle analysis is required).
• Resistance and load effects can be and often are correlated.
• Load must be considered to be a function of time, described by magnitude and frequency of occurrence.
• Resistance may be strongly affected by quality of workmanship, operation procedures and
maintenance.
• Resistance is subject to changes in time, mostly but not only deterioration, with difficulty predicting
initiation time and time-varying rate of deterioration (e.g. corrosion, accumulation of debris, cracking).
• Resistance can depend on geographical location (climate, exposure to industrial pollution, exposure to
deicing agents or proximity to the ocean).
Pavement Deterioration Curve
PCI = Condition
Galehouse et al., 2006
ROCK SLOPE REMAINING SERVICE INTERVAL
(To Change of State - yrs)
Deterioration
models
How are
these levels
related to
Performance
Goals?
Time in Condition State
18
1
11
6
100%
C
O
N
D
I
T
I
O
N
A - Excellent
80%
B - Good
60%
C - Fair
40%
D - Poor
20%
F - Failed
5
10
15
20
25
TIME (yrs)
Theoretical Deterioration Curve
Uncertainty limits
Rock Slope Condition
30
35
40
0%
Example: With four Performance Goals and
four Asset Classes, these are the components
of Level of Service (LOS). A description of
condition with respect to different goals
Asset Class
Linking Condition and Performance
Performance Goals
Asset Classes
Performance Goals
Safety
Infrastructure
Congestion
Environmental
Retaining Walls
LOSRW,S
LOSRW,I
LOSRW,C
LOSRW,E
Slopes
LOSSL,S
LOSSL,I
LOSSL,C
LOSSL,E
Embankments
LOSEM,S
LOSEM,I
LOSEM,C
LOSEM,E
Subgrade
LOSSB,S
LOSSB,I
LOSSB,C
LOSSB,E
Level of Service (LOS) describes condition with respect to Goals
Risk Management
Risk(E) = Probability(E) x Consequence(E)
(Vulnerability included here with Consequence)
“Risk management is an important part of asset
management …” (AASHTO TAM Guide and ES)
MAP 21 reads as follows:
“IN GENERAL—A State shall develop a risk-based asset
management plan for the National Highway System to
improve or preserve the condition of the assets and the
performance of the system.”
Challenge
• Risk is treated as though it is an additional
Performance Measure or Goal (TAMG 5.1.3)
 as though it were additional to Safety, Congestion,
Reliability, etc.
• This leaves open a question (See TAMG 5.4):
“Risk of what; what event is failure?”
• This contributes to an imprecise use of the word,
and confusion…
Proposed Solution
• Explicitly do not consider risk as an additional
Performance Measure or Goal
• Treat risk as related to each and every Performance
Goal, and whether or not it will be met (= “failure”)
 Safety, Congestion, Reliability, etc.
• Define “Level of Service” (LOS) as also related to the
same Performance Goals
Key Point
• LOS is static at a point in time, whereas Risk is related
to the potential rate of change of LOS
 LOS is “today”, what condition and service is the asset providing
through today; it is not uncertain
 Risk is “tomorrow”; all else is the same, but of course it is uncertain
 Risk is related to a prediction, a forecast of LOS change through
action or inaction
(To Change of State - yrs)
Time in Condition State
C
O
N
D
I
T
I
O
N
18
1
11
6
A - Excellent
80%
B - Good
60%
C - Fair
40%
D - Poor
20%
F - Failed
5
100%
10
15
20
25
TIME (yrs)
30
35
40
0%
Risk Sources – sources of the event (E)
 Natural Hazards
• e.g. extreme/rare events
 External Agency Impacts
• e.g. poor materials or construction
 Physical Failure
• e.g. deterioration
 Operational Risk
• e.g. poor design, operation, or business decision
TAM Guide (Section 5.4.1)
All risks can be identified in a 3-D matrix:
 Risk Sources x Assets x Performance Goals
Definition of the Event (E) = “failure”
• Slipping below a condition state – a target LOS
for a Performance Goal
(To Change of State - yrs)
Time in Condition State
18
1
11
6
100%
C
O
N
D
I
T
I
O
N
A - Excellent
80%
B - Good
60%
C - Fair
40%
D - Poor
20%
F - Failed
5
10
15
20
25
30
35
40
0%
TIME (yrs)
30
Risk Cube
GEOTECHNICAL RISK
RRW,E,OR
Operational Risk
Physical Failure
External Agency Impacts
Σ of ALL Risk
Sources on
GEOTECHNICAL
Assets with
respect to ALL
Performance
Goals
Can be done
for GAM
Section,
Corridor or
entire
Retaining Walls
Slopes
Embankments
Subgrade
RRW,I,EAI
RRW,S,NH
Asset Class
Natural Hazards
RRW,C,PF
RRW,S,NH
RSL,I,NH
REM,C,NH
RSB,E,NH
Performance Goals
Simplification
• 64 cells (this example) is too many.
– MAP-21 has 7 Goals … 112 cells
• Eliminate or categorize secondary contributors
• Address Operational Risk and External Agency
Impacts differently through
– Established business practices
– Implementation of QC/QA
Plans
2 Sources are managed
separate from GAM
Operational Risk
Physical Failure
External Agency Impacts
Retaining Walls
Slopes
Embankments
Subgrade
RRW,S,NH
Asset Class
Natural Hazards
RRW,C,PF
RRW,S,NH
RSL,I,NH
REM,C,NH
RSB,E,NH
Performance Goals
GAM Risks
RRW,C,PF
Physical Failure
Retaining Walls
Slopes
Embankments
Subgrade
RRW,S,NH
Asset Class
Natural Hazards
RRW,S,NH
RSL,I,NH
REM,C,NH
RSB,E,NH
Performance Goals
Physical Failure Risk
Source
Physical Failure
RRW,C,PF
Retaining Walls
Slopes
Embankments
Subgrade
Performance Goals
Natural Hazard Risk
Source
Natural Hazards
Retaining Walls
Slopes
Embankments
Subgrade
RRW,S,NH
RRW,S,NH
RSL,I,NH
REM,C,NH
RSB,E,NH
Performance Goals
GAM Section, Corridor or Inventory
Retaining Walls
Slopes
Embankments
LOS
Risk
Performance Goals
Performance Goals
Subgrade
TAM Guide Maturity
Achieve minimum LOS before looking at Risk of falling below it
(might already be there)
US 2, Crookston, MN
 4 months of monitoring
 Could more have been done?
Risk-Based Asset and Performance
Management
Can’t do all we would like
Need to Optimize
Can’t do it all at once
Need to Prioritize
What do you think?
Conclusions
 There is an evolution in practice
 It is multidisciplinary
 Decisions are based on performance and risk
 These are not new ideas for geotechs but there is
lots of opportunity
Questions

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