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Committee 140 Life Cycle Performance & Cost Paul Tourney - Chair Peter DeNicola “You Call It Sustainability, We Call It Concrete Repair” Committee 140 - Life Cycle Performance & Cost MISSION Provide industry guidance for decisions based on both the service extension and economic impact of concrete repairs. GOALS Develop technical guideline on managing the serviceability of concrete structures through a “cradle to grave” approach using preventative maintenance systems and quality concrete repairs. Committee 140 - Life Cycle Performance & Cost Current Membership: Paul Tourney Pete DiNicola Dale Campbell Jason Dunster Kevin Earley Eric Edelson Greg Gilmor Fred Goodwin Joshua Hollis Graeme Jones Richard McGuire Mike Parker Chris Perego Matt Sherman Consulting Members: Frank Apicella James McDonald Jessi Meyer Committee 140 - Life Cycle Performance & Cost Expanded Objectives: • Use excellent work efforts of other ICRI committees. • Develop tools for owners and engineers to promote and justify better concrete repairs. – Decision Tree on “Cradle to Grave” of structures and the maintenance options. – Guidelines for use of the decision tree system. – Provide a series of project case studies for demonstration of SLP / LCCA for optimal management of concrete structure assets. • Liaison with ACI and ISO Committees to build consensus. Importance of Concrete Repair Sustainability Type of Structure #New #Existing Grade Highway Bridges Highway Roads Parking Garages Dams 1,000 X 400 10 600,000+ 100X 25,000+ 4,000 C DC D Importance of Concrete Repair Sustainability Type of Structure #New #Existing Grade Highway Bridges Highway Roads Parking Garages Dams 1,000 X 400 10 600,000+ 100X 25,000+ 4,000 C DC D #1 #2 Build new structures to last longer! Maintain and repair existing structures to significantly extend the time to subsequent repair. The backlog numbers are against us!! Balance of Asset Management of Existing Structures: Periodic Evaluations Repair Service Life Life Cycle Cost TIME LINES of LCCA Activity Time Line Service Life Predictions Cost Time Line All Documents Existing Structure “Birth Certificates” Building Code New Structure TIME LINES of LCCA Option 1 Option 2 Option 3 Option 4 SLM $ Life Cycle Costing Net Present Value (NPV) NPV = Today Cost /(1 + Effective Interest Rate (i)) **(years from today) • What is the $$$ needed to put away today to take care of facility for the expected service life? • Related to the opportunity cost. General rules. – Dollars spent in the future is lower cost than dollars spent today. • Higher the interest rate the greater the premise. – Dollars NOT spent today will result in high Life Cycle Costs. Life Cycle Cost Analysis (LCCA) Discount Rate = i $Z $Y $X T1 T2 T3 NPV = [$X/ (1+i)T1 + $Y/ (1+i)T2 + $Z/ (1+i)T3] Life Cycle Cost Analysis (LCCA) Discount Rate = i New $U $V $W $X $Y $Z Today T1 T2 T3 T4 T5 T6 NPVLife = [$U/ (1+i)T1 + $V/ (1+i)T2 + $W/ (1+i)T3] + …. NPVToday = [$U + $V/ (1+i)T3-T2 + $W/ (1+i)T4-T3] + …. Case 1 End of Serviceability X Repairs 4 Damage 3 2 New Construction Chloride Contamination Period I Corrosion Damage Repaired Damage Corrosion Initiation TIME Ref. Tuutti Case 1 End of Serviceability X Repairs 4 2 New Construction Chloride Contamination Period Cost Damage 3 I Corrosion Damage Repaired Damage Corrosion Initiation Current Cost TIME Ref. Tuutti Case 1 End of Serviceability X i = 7.5% 4 3 2 NPVToday = 1.024 Cost Damage NPVLife = 0.168 I 0.6 0.5 Today 0.4 0.3 New T 25 TIME +5 +5 +5 Ref. Tuutti Case 2 End of Serviceability X Damage Repairs Corrosion Damage I New Construction Chloride Contamination Period Corrosion Initiation Repaired Damage TIME Ref. Tuutti Case 2 End of Serviceability X Corrosion Damage I Cost Damage Repairs New Construction Chloride Contamination Period Corrosion Initiation Current Cost Repaired Damage TIME Ref. Tuutti Case 2 End of Serviceability X i = 7.5% NPVToday = 0.70 I Cost Damage NPVLife = 0.115 0.7 Today New T 25 TIME Ref. Tuutti Case 3 Damage End of Serviceability X Preventative Maintenance Corrosion Damage New Construction Corrosion Initiation Chloride Contamination Period Repair I P P TIME Ref. Tuutti Case 3 X Preventative Maintenance Cost Damage End of Serviceability Corrosion Damage New Construction Corrosion Initiation Chloride Contamination Period Repair Current Cost I P P TIME Ref. Tuutti Case 3 End of Serviceability i = 7.5% [Case 1 = 0.168] [Case 3 = 0.115] NPVToday = 0.146 [Case 1 = 1.024] [Case 3 = 0.70] Preventative Maintenance Today New 0.1 0.1 P 12 0.3 I T P 8 5 TIME +10 Ref. Tuutti Cost Damage NPVLife = 0.089 Life Cycle Cost Comparison NPV (Life) NPV (Today) Case 1 0.168 1.024 Case 2 0.115 0.700 Case 3 0.089 0.146 All Documents Existing Structure “Birth Certificates” Building Code New Structure TIME LINES of Service Life Option 1 Option 2 Option 3 Option 4 SLM $