Comparison of Life-Cycle Maintenance and Rehabilitation Costs for Typical Pavement Systems
The purpose of this report is to present a comparison of maintenance costs for typical pavement systems in public right-of-way areas. Typical Pavement Type and Layers are compared.
Pavement Maintenance and Rehab Costs Unit costs for maintenance and rehabilitation are provided for each pavement type. The unit costs were developed from bid information from medium to large municipalities across Canada and benchmarked with several U.S. municipalities, contractor estimates and private sector developers. The unit costs represent the whole cost to complete the maintenance and rehabilitation activity, including labor, equipment, and materials.
Pavement Maintenance and Rehab Plans
Common Maintenance and Rehabilitation Activities Interlocking Concrete Pavement • • •
Replace Cracked or Worn Pavers Reset Pavers Joint Sand Replenishment
It is important to understand the expected pavement performance and costs for the entire life cycle of the pavement. The overall costs and value need to be determined over many years to effectively consider the different options in terms of pavement type, design life, and future maintenance and rehabilitation. Overall costs are divided into initial or typically capital costs and future or typically operational costs. Initial costs are typically covered by specific capital budgets and, in the municipal environment, in many cases by developers who design and construct the roadway infrastructure to municipal specifications. Therefore, for the purpose of this analysis, only future operational costs are included in the LCCA.
Two common categories of pavement are considered here: •
Low Volume Roads/Parking Areas - A pavement built for its appropriate traffic and environmental conditions will have a reasonable service life while providing a functional, safe platform for the traveling public.
•
Sidewalks/Recreational Trails - While sidewalks can be considered as pavement, they are not typically subjected to a formal pavement structural design. Municipal agencies across North America have developed “typical” thickness designs based on their experience with past performance of sidewalks in their jurisdictions.
Asphalt Concrete • • • • •
Rout and Seal Spot Repair Full-Depth Base Repair Mill AC Resurface AC
Concrete • • • • • •
Re-seal Joints Partial Depth Concrete Repair Full Depth Concrete Repair Sidewalk Concrete Panel Replacement Concrete Edge Grinding Slab Jacking
Pavement System Life-Cycle Cost Comparisons Roadway/Parking Area Maintenance and Rehabilitation
Sidewalk/Recreational Trail Maintenance and Rehabilitation
The maintenance and rehabilitation plans outlined in this comparison were used in conjunction with typical municipal costs and a discount rate of 4 percent to develop the comparison of maintenance and rehabilitation costs.
maintenance and operation costs for ICP on a concrete base are 6 percent lower than for PCC on an aggregate base. For AC on aggregate base the cost is 63 percent lower compared to PCC on an aggregate base. The higher costs for PCC on an aggregate base and ICP on a concrete base are primarily due to the cost of concrete slab replacements and undersealing to address settlements and distortions.
For roads and parking areas, the 50-year life-cycle maintenance costs for ICP on an aggregate base are 19 percent lower than for AC on an aggregate base. The life-cycle maintenance costs for ICP on a concrete base are 21 percent higher than for AC on an aggregate base. The life-cycle maintenance costs for PCC on an aggregate base are 26 percent less than for AC on an aggregate base. The higher cost for ICP on a concrete base is primarily due to the cost of concrete slab replacements. For sidewalk and recreational trail areas, the 40year maintenance and operations costs for ICP on an aggregate base are 52 percent less than for PCC on an aggregate base. The life cycle
Interlocking concrete pavers are an important element for Complete Streets. They are sustainable, they look better and they have proven performance. As this report shows pavers provide a more economical solution to traditional pavements when considering their long-term maintenance.
About Interlocking Concrete Pavement Institute ICPI is the trade association representing the growing industry of segmental concrete pavement systems in the Canada and United States. The association's membership includes producers, contractors, suppliers, design professionals and distributors. ICPI is the authority for concrete pavers, which are universally recognized as the best value for pavement systems. The association delivers education and technical guidance leading to awareness, acceptance and use of segmental concrete pavement systems in the Canada and United States. For more information, visit www.icpi.org.
14801 Murdock Street, Suite 230 | Chantilly, VA 20151 PO Box 1150 | Uxbridge, ON L9P 1R2 703.657.6900 www.icpi.org
Comparison of Life-Cycle Maintenance and Rehabilitation Costs for Typical Pavement Systems
Prepared for: Interlocking Concrete Pavement Institute 14801 Murdock Street, Suite 230 Chantilly, Virginia 20151
Prepared by: Mr. David K. Hein, P.Eng. Principal Engineer President 2737493 Ontario Limited 332 Terrace Wood Crescent Kitchener, Ontario N2P 0A7 (519) 219-0533 July 27, 2021
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Table of Contents Introduction ............................................................................................................................................. 1 Segmental Pavement Background ........................................................................................................... 1 Pavement Sections................................................................................................................................... 3 Low Volume Roads/Parking Areas .................................................................................................................... 3 Sidewalks/Recreational Trails ........................................................................................................................... 5
Pavement Maintenance and Rehabilitation ............................................................................................ 6 Common ICP Maintenance and Rehabilitation Activities ................................................................................. 6 Common Asphalt Concrete Maintenance and Rehabilitation Activities........................................................... 7 Common Concrete Maintenance and Rehabilitation Activities ........................................................................ 8 Pavement Maintenance and Rehabilitation Costs ............................................................................................ 9 Pavement Maintenance and Rehabilitation Plans .......................................................................................... 11
Low Volume Roads/Parking Areas ...................................................................................................... 11 Sidewalks/Recreational Trails ............................................................................................................. 14
Life-Cycle Cost ........................................................................................................................................ 16 Calculations of Net Present Value................................................................................................................... 17 Residual Value................................................................................................................................................. 17 Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison .................................................. 17 Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison ........................................... 18
Conclusions ............................................................................................................................................ 19 Closure ................................................................................................................................................... 20 Appendix A - Life-Cycle Cost Details – Low Volume Roads/Parking Areas Appendix B - Life-Cycle Cost Details – Sidewalks/Recreational Trails
List of Tables Table 1. Pavement Types and Use. .............................................................................................................. 1 Table 2. Roadway/Parking Lot Maintenance and Rehabilitation Costs. .................................................... 10 Table 3. ICP Roadway/Parking Area Maintenance Plan (Aggregate Base/Subbase). ................................ 12 Table 4. ICP Roadway/Parking Area Maintenance Plan (Concrete Base/Subbase). .................................. 12 Table 5. AC Roadway/Parking Area Maintenance Plan (Aggregate Base/Subbase). ................................. 13 Table 6. PCC Roadway/Parking Area Maintenance Plan (Aggregate Base). .............................................. 14 Table 7. ICP Sidewalk/Recreational Trail Preservation Plan (Aggregate Base). ......................................... 14 Table 8. ICP Sidewalk/Recreational Trail Maintenance Plan (Concrete Base/Subbase). ........................... 15 Table 9. AC Recreational Trail Maintenance Plan (Aggregate Base/Subbase)........................................... 15 Table 10. PCC Sidewalk Maintenance Plan (Aggregate Base). ................................................................... 16 Table 11. Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison.............................. 18 Table 12. Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison. ..................... 19 List of Figures Figure 1. Low Volume Roads/Parking Areas Pavement Type and Layers. ................................................... 4 Figure 2. Sidewalks/Recreational Trails Pavement Type and Layers. .......................................................... 5
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Figure 3. Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison. ............................. 18 Figure 4. Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison. ...................... 19 Glossary of Abbreviations AADT AASHTO ACPA AC ASCE ASTM CAC CBR CPR ICP ICPI LCC LCCA MPa M&R PCI PCC PPE RMCAO
- Average Annual Daily Traffic - American Association of State Highway and Transportation Officials - American Concrete Pavement Association - Asphalt Concrete - American Society of Civil Engineers - American Society for Testing Materials - Cement Association of Canada - California Bearing Ratio - Concrete Pavement Restoration - Interlocking Concrete Pavement - Interlocking Concrete Pavement Institute - Life-Cycle Cost - Life-Cycle Cost Analysis - Megapascal - Maintenance and Rehabilitation - Pavement Condition Index - Portland Cement Concrete - Personal Protective Equipment - Ready Mixed Concrete Pavement Association
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Introduction The Interlocking Concrete Pavement Institute (ICPI), founded in 1993, is the trade association representing the segmental concrete pavement industry in the United States and Canada. ICPI is considered by peer associations around the world as the leader in development and dissemination of technical information for design professionals and contractors. ICPI engages in a broad range of technical, marketing, educational, government relations and communications activities. The purpose of this report is to present a comparison of life-cycle maintenance details for typical pavement systems in public right-of-way areas as shown in Table 1. Table 1. Pavement Types and Use. Pavement Type Interlocking Concrete Pavers on Aggregate Base Interlocking Concrete Pavers on Concrete Base Asphalt Concrete on Aggregate Base Portland Cement Concrete on Aggregate Base
Sidewalks/ Recreational Trails
Low Volume Roads/Parking Areas
√ √ √ √
√ √ √ √
Segmental Pavement Background Forms of segmental pavements have been around for thousands of years. The early Romans recognized the vital nature of a high-quality transportation network. At its peak, the Roman Empire included over 80,000 kilometers of stone surfaced roadways. Many of these roadways are still in existence or have formed the base of modern roads. In the mid-1950s, the Dutch adapted the Roman roadways and replaced the natural cut stone surfaces and clay brick with molded concrete pavers. It was necessary for roadways in Holland to be flexible since most of the country is below sea level and the roadway subgrade can shift or settle with time. Segmental paving enabled the rapid rehabilitation of settled soils and bases while reinstating the same paving units. This allowed Dutch roadway agencies the ability to maintain a safe and durable road network in a sustainable manner. The first production of concrete pavers in North America was in 1973 in Canada. Pavers are manufactured using state-of-the-art specialty machines. Pavers are made from a dry mix of aggregate, cement and color which is pressed into molds and vibrated under high pressure. Once cured, the finished paver is installed on top of a bedding sand layer (typically 25 mm thickness) over a base/subbase of aggregate, which may be stabilized with asphalt or concrete, or be Portland cement concrete over the natural subgrade. Interlock of the pavers is provided -1-
through the installation of sand placed and vibrated into the joints between the individual pavers. This provides shear transfer of applied wheel loads between the paver units to support to vehicular traffic. Paver surfaced pavements can accommodate very heavy loading. Interlocking concrete pavements have significant advantages over conventional asphalt and concrete surfaced pavements. These include:
Very durable due to construction method and very high compressive strength (typically > 55 MPa compared to 30 MPa used for conventional concrete pavements);
The only commonly used pavement surface whose physical properties can be verified before installation on the roadway (the properties of asphalt and concrete are subject to physical placement variation including compaction, curing etc.);
Once placed, the surface is immediately ready for traffic;
Does not require expensive production, transportation and installation equipment;
High resistance to point loads and surface scarring (pavement surface of choice for ports and intermodal terminals);
While the pavement surface is considered a semi-rigid (physical pavers are made of concrete), the pavement system is flexible and able to conform to settlements and subgrade movement without compromising structural capacity;
Ability to temporarily remove the surface to address settlements and access underground utilities and then be reinstated without leaving any permanent evidence from repairs to utility cut;
Ability to accommodate expansion and contraction of the product (paver) without permanent cracking or deformation. When homogeneous layers of asphalt and concrete expand and contract, they may eventually crack and require replacement;
Provided the pavement base/subbase layers are adequate to support traffic, the pavement system is not subject to “fatigue” cracking due to pavement overloading which can happen with asphalt and concrete surfaced pavements;
Ease and simplicity of future maintenance and rehabilitation (much simpler and less expensive maintenance and rehabilitation options);
Long life due to the durability of the pavers can provide a significant salvage value due to the ability to reuse them;
Reduced maintenance cost for pavement and crosswalk stripping as colored pavers can be used in lieu of paint or thermoplastic markings which require frequent update or replacement;
Ability to make “all season” repairs to interlocking concrete pavements, i.e. in northern environments, most asphalt plants are closed in the winter and it is difficult and expensive to “cure” concrete in below freezing conditions;
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Reduced impact on the travelling public due to the ability to make more rapid maintenance repairs to an interlocking concrete pavement compared to conventional asphalt or concrete;
Ability to provide traffic calming and vehicle speed reductions without the use of speed bumps or humps;
When used for “permeable” pavements, the system can substantially contribute to stormwater quantity and quality control thereby reducing pressure on other stormwater infrastructure and water quality improvement needs; and
Aesthetically pleasing due to many different shapes, sizes, laying patterns and colors (public perception of increased value compared to asphalt and concrete surfaces).
As with any pavement, it is of paramount importance to ensure the highest quality of construction to achieve a long service life with minimal maintenance and rehabilitation costs. Attention to detail during the construction of an interlocking concrete pavement can ensure a service life of 30 to 50 years. A good local example of this is Main Street in North Bay, Ontario. The paver surface on Main Street was constructed in 1983 and has lasted over 37 years with minimal maintenance. In late 2020, the City issued a request for proposal to update the roadway infrastructure on Main Street and based on the preliminary plans, they will continue to use pavers. (https://icpi.org/case-studies/north-bay-case-study-2015)
Pavement Sections The pavement surfaces in this report include interlocking concrete pavers (ICP), asphalt concrete (AC) and Portland cement concrete (PCC). Each pavement type includes a dense graded base/subbase except for ICP over concrete base which has a concrete base and dense aggregate subbase. Pavement sections used by municipal agencies in Canada are typically based on the intended use of the pavement (pedestrian, bicycle, light and heavy vehicles, etc.), subgrade type and composition (sand, silt, clay, etc.) and expected volume of traffic. The ultimate cross section may be based on a formal pavement design procedure as is typically done for pavement subjected to frequent and heavy vehicle traffic or based on experience as is typically done for sidewalks and recreational trails. Typical pavement sections specified by medium to large municipalities in Canada for each pavement type and use shown in Table 1 are presented in the following sections. Low Volume Roads/Parking Areas A pavement built for its appropriate traffic and environmental conditions will have a reasonable service life while providing a functional, safe platform for the traveling public. The service life of a pavement is established during the initial design considering the subgrade, -3-
pavement layer materials and their thicknesses, the anticipated traffic using the roadway, and the budget. This service life can be somewhat variable depending on the environmental and loading conditions. The typical pavement sections for each of the pavement surfaces for low volume roads/parking areas used for the analysis are shown in Figure 1. Figure 1. Low Volume Roads/Parking Areas Pavement Type and Layers.
Figure 1a. Interlocking Concrete Pavers on Aggregate Base/Subbase.
Figure 1b. Interlocking Concrete Pavers on Concrete Base.
Figure 1c. Asphalt Concrete on Aggregate Base/Subbase.
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Figure 1d. Portland Cement Concrete on Aggregate Base.
Sidewalks/Recreational Trails While sidewalks can be considered as pavement, they are not typically subjected to a formal pavement structural design. Municipal agencies across North America have developed “typical” thickness designs based on their experience with past performance of sidewalks in their jurisdictions. Sidewalk sections are subject to pedestrian, cyclists and occasional pick-up trucks and/or snow removal equipment. The typical pavement sections for each of the pavement surfaces for sidewalks/recreational trails is shown in Figure 2. Figure 2. Sidewalks/Recreational Trails Pavement Type and Layers.
Figure 2a. Interlocking Concrete Pavers on Aggregate Base/Subbase.
Figure 2b. Interlocking Concrete Pavers on Concrete Base.
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Figure 2. Sidewalks/Recreational Trails Pavement Type and Layers.
Figure 2c. Asphalt Concrete on Aggregate Base/Subbase.
Figure 2d. Portland Cement Concrete on Aggregate Base.
Pavement Maintenance and Rehabilitation All pavements require maintenance and rehabilitation. Annual day-to-day summary and winter maintenance activities that are part of agency operations are not typically included in the lifecycle cost analysis. While the most common cause of pavement damage is usually related to vehicular loading, environmental conditions such as freezing and thawing, moisture, thermal expansion and contraction, oxidation of asphalt bounding materials, etc. also result in degradation of the pavement materials and subgrade. Common municipal rehabilitation activities related to each type of pavement are described below. Common ICP Maintenance and Rehabilitation Activities Replace Cracked or Worn Pavers: Replacing one or several pavers that have been damaged. Typical equipment needed includes personal protective equipment (PPE), a vehicle to remove debris, metal putty knife, paver extractor, wooden or metal bedding sand screed, plate compactor and a broom. Materials required include replacement paver(s), bedding/joint sand. Scrape the sand from the joints around the paver to be replaced using a metal putty knife, pry the paver upwards using a paver extractor or 2 flat head screw drivers, level the bedding sand layer and add sand (if necessary), place the replacement paver, compact using a small plate compactor, fill the joints with dry sand and compact again to seat the joint sand and sweep the excess sand from the repair area.
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Reset Pavers: Address areas which are no longer level due to heave or settlement. Typical equipment needed includes PPE, a metal putty knife, paver extractor wooden or metal bedding sand screed, plate compactor and a broom. Materials required is bedding/joint sand. Scrape the sand from the joints around a single paver using a metal putty knife, pry the paver upwards using a paver extractor or 2 flat head screw drivers, remove and retain surrounding pavers necessary to complete the repair, address any base issues adding additional granular base if necessary, place and screed the new bedding sand such that when placed, the pavers will be 2 to 3 mm above the adjacent paver surface to account for compaction, compact the pavers using a small plate compactor, fill the joints with dry sand and compact again to seat the joint sand and sweep the excess sand from the repair area. Joint Sand Replenishment: Maintains interlock between pavers. Typical equipment needed includes PPE, a broom and a small plate compactor. Materials include joint sand. Remove debris from the affected area. Place the dry joint sand on the dry pavement surface, sweep into the joints, lightly compact with a plate compactor with a rubber pad bottom to protect the pavers from damage. Common Asphalt Concrete Maintenance and Rehabilitation Activities Rout and Seal: Addresses low to medium severity longitudinal, transverse, and meandering cracking. Typical equipment needed includes PPE, high pressure air compressor, router, broom, hot-poured rubberized asphalt melting kettle and applicator. Materials include rubberized asphalt sealant and fine dust or cement. Clean all loose debris from the cracked area using a high-pressure air hose or hot air lance, rout the crack to provide a uniform depth and width reservoir, place hot-poured rubberized asphalt sealant in the reservoir, “dust” to surface of the sealant to prevent “pick-up” before the crack sealant stiffens. Spot Repair: Address small area defects such as settlements, ravelling and other low to medium severity area cracking. Typical equipment includes PPE, masonry saw, broom small milling machine, truck or trailer to remove debris and deliver asphalt concrete and a plate compactor. Materials include asphalt concrete and granular base. Cut out or mill and remove some or all of the asphalt concrete, place additional granular base, if necessary, compact and place asphalt concrete and compact to ensure a uniform and continuous surface. Full-Depth Base Repair: Addressed more severe small area deflects such as moderate to high severity settlements, heaving or fatigue cracking. Typical equipment includes PPE, broom, masonry saw, small milling machine, truck or trailer to remove debris and deliver asphalt concrete, granular base and subbase (if necessary), appropriate compactor(s), router, hotpoured rubberized asphalt melting kettle and applicator and fine dust or cement. Materials include asphalt concrete, granular base/subbase and rubberized asphalt sealant. Saw-cut and remove the asphalt, base, subbase and portion of the subgrade as necessary to address the -7-
defect. Place and recompact the subgrade and pavement layers to ensure a uniform continuous surface, rout and seal the repair joint with the surrounding asphalt concrete. Mill AC: Addresses surface defects such as oxidation, low severity cracking and smoothness prior to the placement of one or more new asphalt layers. Typical equipment includes PPE, broom, milling machine and a truck to transport millings off-site. Mill the surface of the asphalt concrete to the depth specified, reserving the millings for potential recycling, sweep and clean the surface in preparation for a new layer of asphalt concrete. Resurface AC: Normally follows a milling operation to provide a smooth pavement surface and possible increase in pavement structural capacity. Typical equipment includes PPE, asphalt paver, truck to deliver asphalt concrete and appropriate roller compaction equipment. Materials include emulsified asphalt tack coat and hot mixed asphalt concrete. Sweep the pavement surface if necessary and place and compact the asphalt concrete in one or more layers as appropriate. Common Concrete Maintenance and Rehabilitation Activities Reseal Joints: Restores longitudinal and transverse joints in concrete pavement. Remove partial or all concrete joint sealants and replace with material in kind. Typical equipment includes PPE, and equipment depending on the type of sealant used. Materials needed include hot-poured rubberized asphalt, silicon or pre-formed neoprene sealant. Partial Depth Concrete Repair: Repair for local surface defects such as spalling, and corner cracking. Typical equipment includes PPE, chipping hammer, high pressure air hose, spray washer, concrete mixer, and surface texturizing equipment such as a tine or broom. Materials include water, expansion board, joint sealant, cement slurry or other bonding agent and concrete. Remove spalled or cracked concrete using a light jack chipping hammer, clean the surface of the exposed concrete using high pressure air/spray washing, coat the bottom and sides of the repair area using a cement slurry or other bonding agent, re-establish any joints in the repair area and pour concrete having similar coefficient of thermal expansion as the surrounding concrete, cure and surface texturizes. Full Depth Concrete Repair: Replacement of part or entire concrete panels where the distress is such that localized repairs would be ineffective. Typical equipment required includes, PPE shovel, sledge hammer, axe, pry bar, rake, pick, broom, concrete saw, jackhammer, truck to remove debris, plate compactor, trowel, jointer tool, screed board, bull float, hand float, tining tool and broom. Materials typically include expansion board, concrete and joint sealant. Some agencies may also include dowels in construction joints, and if so, would require steel dowels, drilling equipment and epoxy sealant to fill the space between the dowels and the drilled concrete. Sawcut edges of the concrete/panels to be replaced, jackhammer, remove and -8-
dispose of broken concrete, level base and top up with granular base as necessary and compact, place expansion board material as necessary, pour new concrete, form contraction joints, broom finish surface, cure concrete and replace joint sealant. Sidewalk Concrete Panel Replacement: Repairs to slab cracking, material defects such as scaling and ravelling, surface openings, raised or sunken areas and root damage. Typical equipment required includes, personal protective equipment (PPE) shovel, sledge hammer, axe, pry bar, rake, pick, broom, concrete saw, jackhammer, truck or trailer to remove debris, form boards, stakes, plate compactor, trowel, jointer tool, screed board, bull float, hand float, broom and edging tool. Typical materials include expansion board, concrete, topsoil and grass seed. Sawcut edges of the concrete/panels to be replaced, jackhammer, remove and dispose of broken concrete, level base and top up with granular base as necessary and compact, place edge forms, place expansion board material as necessary, pour new concrete, form contraction joints, broom finish surface, cure concrete, remove edge forms and restore landscaping adjacent to the repair (top soil, grass seed, etc.). Some agencies may also include dowels in construction joints, and if so, would require steel dowels, drilling equipment and epoxy sealant to fill the space between the dowels and the drilled concrete. Concrete Edge Grinding: Removes trip hazards up to 25 mm in height. Typical equipment needed includes PPE and a masonry grinder. For a 12 mm trip hazard grind full width and 150 mm back from the adjacent slab. For a 25 mm trip hazard grind full width and 300 mm back from the adjacent slab. Ensure slip resistance of the ground surface by roughening the surface with a saw blade or other approved method. Slab Jacking: Levels uncracked concrete slabs up to 50 mm in height. Typical equipment needed includes PPE, a masonry drill and core bit (capable of drilling at 25 to 50 mm core), vehicle equipped with a grout mixer, grout pump, 2-m level, measuring tape or other device to measure that sidewalk is level and broom. Materials required grout and stiff concrete to fill the drill hole. Drill hole through concrete slab in low area. Pump grout through hole into area under concrete slab, raising slab until it is level. When the grout is stable, seal hole with concrete. Pavement Maintenance and Rehabilitation Costs Unit costs for maintenance and rehabilitation are provided for each pavement type. The unit costs were developed from bid information from medium to large municipalities across Canada and benchmarked with several U.S. municipalities, contractor estimates and private sector developers. The unit costs represent the whole cost to complete the maintenance and rehabilitation activity, including labor, equipment, and materials. These costs should be
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adjusted as necessary for local prices and experience when using the LCCA tools provided for specific projects. Maintenance and rehabilitation costs are provided in Table 2. Each unit cost can vary significantly depending on location, size of the project, manual or machine assisted installation, availability of materials and contractors, etc. The unit costs can also vary significantly based on the method of contracting. For example, repairs that are part of a much larger contract can result in high unit rates for small quantity items. Smaller contracts made directly with firms that specialize in pavement maintenance and preservation can result in much lower unit rates. The unit costs should be adjusted as necessary for local prices and experience when using the LCCA tools for specific projects. Table 2. Roadway/Parking Lot Maintenance and Rehabilitation Costs. Unit Cost ($) Roadway/Parking Sidewalk/Trail
Treatment Pavers on Aggregate Base Replace cracked pavers (m2) Reset pavers (m2) Joint sand replenishment (m2) Pavers on Concrete Base Replace cracked pavers (m2) Reset pavers (m2) Joint sand replenishment (m2) Concrete panel replacement (m2) Slab jacking (m2) Asphalt Concrete on Granular Base Transverse crack rout and seal asphalt (m) Spot repairs, mill and patch (m2) Full depth asphalt base repair (m2) Mill AC (mm/m2) Resurface with AC surface (mm/m2) Portland Cement Concrete on Granular Base Reseal concrete joints (m) Partial depth PCC repair (m2) Full depth PCC repair (m2) Concrete panel replacement (m2) Concrete edge grinding (per 1-1.5 m) Slab jacking (m2) Note:
120.00 55.00 5.00
120.00 55.00 5.00
120.00 25.00 5.00 -
120.00 25.00 5.00 225.00 75.00
5.00 35.00 45.00 0.05 0.30
5.00 35.00 45.00 0.05 0.30
12.00 200.00 150.00 -
225.00 30.00 75.00
Milling and AC surface costs based on millimeter thickness of AC per metre square. Based on a typical AC unit weight of 2,500 kg/t, multiple unit cost/m2 x 400 to obtain AC price/tonne.
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Pavement Maintenance and Rehabilitation Plans It is important to understand the expected pavement performance and costs for the entire life cycle of the pavement. The overall costs and value need to be determined over many years to effectively consider the different options in terms of pavement type, design life, and future maintenance and rehabilitation. Life-cycle cost analysis (LCCA) has been used for many years to help make decisions regarding pavement type as well as selecting pavement preservation options. Broadly, the overall costs are divided into initial or typically capital costs and future or typically operational costs. Initial costs are typically covered by specific capital budgets and, in the municipal environment, in many cases by developers who design and construct the roadway infrastructure to municipal specifications. Therefore, for the purpose of this analysis, only future operational costs are included in the LCCA. In a typical LCCA, two or more alternate choices are available for an initial pavement design or cross-section. At the end of the initial service life, some form of rehabilitation, such as a mill and overlay for a flexible pavement, replacement of worn or cracked pavers for ICP and slab repairs and possible diamond grinding for smoothness and surface friction restoration for a rigid pavement, is usually required. Based on the initial pavement designs, the expected maintenance and rehabilitation over the design life are then determined and incorporated into a single, inflation-adjusted cost in order to evaluate and compare the different options in a fair and consistent manner. An analysis period of 50 years was used for the roadways/parking areas and 40 years for the sidewalks/ trails. Low Volume Roads/Parking Areas Typical maintenance plans for low volume roads/parking areas are provided in the sections below. The maintenance schedule for asphalt concrete and concrete over aggregate base/subbase are based on a technical report titled “Methodology for the Development of Equivalent Pavement Structural Design Matrix for Municipal Roadways including Maintenance and Rehabilitation Schedules and Life-Cycle Cost Analysis”, for the Ready Mixed Concrete Association of Ontario & Cement Association of Canada” (RMCAO/CAC) in 2011. Interlocking Concrete Pavers on Aggregate Base/Subbase ICPs have been used by many municipalities across North America. Use of ICP for municipal pavements is typically based on development requirements for a high-quality appearance in specific areas of the city attracting tourist and retail type activities. The recommended maintenance and rehabilitation schedule for ICP on a granular base/subbase are outlined in Table 3 below. This plan was developed based on a research study completed by ICPI to develop an ICP pavement surface distress identification manual in 2008. This manual was the predecessor to the development of ASTM E2840 Standard Practices for Pavement Condition Index Surveys for Interlocking Concrete Roads and Parking Lots. The - 11 -
maintenance and rehabilitation quantities provided are for a 1 km length of 2-lane roadway and will need to be adjusted for different section lengths or areas in the case of a parking lot if necessary. Table 3. ICP Roadway/Parking Area Maintenance Plan (Aggregate Base/Subbase). Expected Year 8 18 18 18 28 28 28 38 38 38 48
Activity Description Reset Pavers Replace Worn/Rutted Pavers (wheelpath) Reset Pavers Joint Sand Replenishment Replace Cracked Pavers Reset Pavers Joint Sand Replenishment Replace Worn/Rutted Pavers (wheelpath) Reset Pavers Joint Sand Replenishment Replace Cracked Pavers
Quantity (per 2 lane 1 km of road) 2% 5% 5% 25 % 2% 5% 25 % 5% 5% 25 % 3%
Interlocking Concrete Pavers on Concrete Base The recommended maintenance and rehabilitation schedule for ICP on a concrete base/subbase are outlined in Table 4. Table 4. ICP Roadway/Parking Area Maintenance Plan (Concrete Base/Subbase). Expected Year 8 18 18 18 28 28 28 38 38 25 38 48
Activity Description Reset Pavers Replace Cracked Pavers Reset Pavers Joint Sand Replenishment Replace Cracked Pavers Reset Pavers Joint Sand Replenishment Full Depth PCC Repair Replace Cracked Pavers Reset Pavers Joint Sand Replenishment Replace Cracked Pavers
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Quantity (per 2 lane 1 km of road) 2% 5% 5% 5% 2% 5% 10 % 10 % 5% 5% 10 % 3%
Asphalt Concrete on Aggregate Base/Subbase Asphalt Concrete (AC) pavements have been commonly used by municipalities due to their history of use and experience with maintenance and rehabilitation. Asphalt pavements typically deteriorate faster than ICP and PCC pavements and require a more extensive maintenance schedule to maintain an acceptable level of service. The recommend maintenance and rehabilitation schedule for AC on a granular base/subbase is shown in Table 5. The AC pavement maintenance plans are developed based on the RMCAO/CAC report. The maintenance plan includes a combination of preventive maintenance and rehabilitation. The quantities provided are for a 2-lane 1 km length roadway and will need to be adjusted for different section lengths or areas in the case of a parking lot if necessary. Table 5. AC Roadway/Parking Area Maintenance Plan (Aggregate Base/Subbase). Expected Year 10 10 20 20 25 30 35 35 35 40 43 48 48
Activity Description Rout and seal Spot repairs, mill 40 mm/patch 40 mm Mill AC Resurface with AC surface course Rout and seal Spot repairs, mill 40 mm/patch 40 mm Mill AC Full depth asphalt base repair Resurface with AC surface course Rout and seal Spot repairs, mill 40 mm/patch 40 mm Mill AC Resurface with AC surface course
Quantity (per 2 lane 1 km of road) 250 m 2% 40 mm 40 mm 500 m 5% 40 mm 5% 40 mm 500 m 5% 40 mm 40 mm
Portland Cement Concrete on Aggregate Base Concrete pavements have been used by municipalities intermittently across North America often depending on local pricing, availability of aggregates and local contractors capable of placing concrete pavements. The recommended maintenance and rehabilitation schedules for PCC pavements are outlined in Table 6. The maintenance plan includes a combination of preventive maintenance and rehabilitation. The maintenance and rehabilitation quantities provided are for a 2-lane 1 km length roadway and will need to be adjusted for different section lengths or areas in the case of a parking lot if necessary.
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Table 6. PCC Roadway/Parking Area Maintenance Plan (Aggregate Base). Expected Year 12 25 25 25 40 40 40
Activity Description Reseal joints Partial depth PCC repair Full depth PCC repair Reseal joints Partial depth PCC repair Full depth PCC repair Reseal joints
Quantity (per 2 lane 1 km of road) 20 % 2% 5% 40 % 5% 10 % 40 %
Sidewalks/Recreational Trails Typical maintenance plans for sidewalks/recreational trails are provided for each type of pavement in the sections below. Interlocking Concrete Pavers on Aggregate Base/Subbase ICPs have been used for sidewalks by municipalities intermittently across North America. Usage of ICP for municipal sidewalks is typically based on development requirements for a high-quality appearance in specific areas of the city attracting tourist and retail type activities. The recommended maintenance schedule for interlocking concrete sidewalks is outlined in Table 7. The maintenance quantities provided are for a 100 m length and will need to be adjusted for different section lengths or areas if necessary. Table 7. ICP Sidewalk/Recreational Trail Preservation Plan (Aggregate Base). Expected Year 10 15 15 20 25 30 35 35
Activity Description Reset Pavers (m²) Replace Cracked Pavers (m²) Joint Sand Replenishment (m²) Reset Pavers (m²) Joint Sand Replenishment (m²) Reset Pavers (m²) Replace Cracked Pavers (m²) Joint Sand Replenishment (m²)
Quantity (per 100 m length) 5% 3% 5% 15 % 15 % 15 % 15 % 15 %
Interlocking Concrete Pavers on Concrete Base The recommended maintenance and rehabilitation schedule for ICP on a concrete base/ subbase are outlined in Table 8.
- 14 -
Table 8. ICP Sidewalk/Recreational Trail Maintenance Plan (Concrete Base/Subbase). Expected Year 10 10 15 15 25 25 25 35 35 35
Activity Description Slab jacking (m2) Reset Pavers (m2) Slab jacking (m2) Reset Pavers (m2) Concrete Panel Replacement (m2) Slab jacking (m2) Reset Pavers (m2) Concrete Panel Replacement (m2) Slab jacking (m2) Reset Pavers (m2)
Quantity (per 100 m length) 5% 5% 10 % 10 % 5% 10 % 10 % 10 % 10 % 10 %
Asphalt Concrete on Aggregate Base/Subbase Asphalt concrete while rarely used for sidewalks, is the pavement type of choice for hard surfaced recreational trails. Recreational trails are typically wider than sidewalks in the order of 3 to 4.5 m in width. However, for comparison purposes, a 1.5 m width of recreational trail was used for the maintenance calculations. The recommended maintenance schedule for AC trails is outlined in Table 9. The maintenance quantities provided are for a 100 m length and will need to be adjusted for different section lengths or areas if necessary. Table 9. AC Recreational Trail Maintenance Plan (Aggregate Base/Subbase). Expected Year 10 10 20 20 25 30 35 35 35 40
Activity Description Transverse crack rout and seal Spot repairs, mill 40 mm and patch 40 mm Mill AC Resurface with AC surface course Transverse crack rout and seal Spot repairs, mill 40 mm and patch 40 mm Mill AC Full-depth asphalt base repair Resurface with AC surface course Transverse crack rout and seal
Quantity (per 100 m length) 7.5 m 2% 40 mm 40 mm 15 m 5% 40 mm 5% 40 mm 15 m
Portland Cement Concrete on Aggregate Base PCC while rarely used for recreational trails is the pavement type of choice for hard surfaced sidewalks in North America. The recommended maintenance schedule for concrete sidewalks is outlined in Table 10. The maintenance quantities provided are for a 100 m length for comparison purposes and should be adjusted for the actual project section lengths. - 15 -
Table 10. PCC Sidewalk Maintenance Plan (Aggregate Base). Expected Year 10 10 15 15 25 25 25 35 35 35
Activity Description Slab jacking (m2) Concrete edge grinding (per 1-1.5m) Slab jacking (m2) Concrete edge grinding (per 1-1.5m) Concrete panel replacement (m2) Slab jacking (m2) Concrete edge grinding (per 1-1.5m) Concrete panel replacement (m2) Slab jacking (m2) Concrete edge grinding (per 1-1.5m)
Quantity (per 100 m length) 5% 5% 5% 15 % 10 % 10 % 15 % 15 % 10 % 10 %
Life-Cycle Cost Life-cycle costing (LCC) has become an essential component of any modern infrastructure design. It has long been realized that maintenance and rehabilitation costs, not just the immediate initial construction costs should be considered when evaluating investment alternatives. The service life of a pavement is defined as the time between initial construction and the time when the pavement reaches a minimum unacceptable level of service. Municipal pavements are typically designed for an initial service life of 20 to 30 years. At the end of the initial service life, some form of rehabilitation action such as removal and resetting of concrete pavers for ICP, mill and overlay for AC pavements and concrete pavement restoration (CPR) consisting of full or partial depth repairs, load transfer retrofit, etc. for PCC is completed. The actual service life of the pavement is dependent on a variety of factors including type and composition of the traffic, timeliness of maintenance treatments, and environmental factors such as climate, temperature and precipitation. To develop comparative cost estimates to determine the whole life cost of different pavement types, it is necessary to know the timing, type and quantities of repairs and their service life. Life-cycle costing is a technique that quantifies all the costs necessary to construct and maintain a pavement over a set analysis period, typically between 30 and 50 years. Future costs are discounted to today’s dollars by using a discount rate which accounts for the effects inflation (future value of money) and interest rates (the cost of borrowing money) to determine the net present value of future costs. By comparing the total life-cycle cost of two or more pavement options, it is possible to make informed decisions on the best pavement alternative for a particular application. Life-cycle costing can be used to benchmark potential pavement options to determine which is the most cost effective. Traditionally, when performing a life-cycle cost analysis comparing pavement surface types, the capital costs for initial construction and maintenance and rehabilitation costs for each of the pavement types are considered. - 16 -
Calculations of Net Present Value The costs distributed over the pavement life are typically translated into a Net Present Value (NPV). The NPV represents the today’s total cost expenditures made in the future. Such expenditures account for the interest minus inflation rate (in percent) expressed as the discount rate. The NPV of all activities each occurring in the future are summed to estimate the total maintenance and rehabilitation cost. This summation of activities is expressed as: Total M&R Cost = ∑ (
( & (
) )
)
The discount rate typically reflects the cost borrowing money for public sector projects and is dependent on many factors such as current economic environment, municipal solvency, market risk, and many other potential factors. It often reflects the difference between the prevailing (market) loan interest rate and the inflation rate. A typical discount rate used by municipal agencies is in the range of 3 to 5 percent. The LCCA analysis has been completed for a discount rate of 4 percent. Residual Value To ensure fair comparison of the alternatives, residual value of any unused rehabilitation activity at the end of the analysis period must be included in the LCCA. The residual value is estimated by the straight-line depreciation of the last capital activity cost. The prorated life method is used in the LCCA procedure to estimate the residual value. The recoverable cost is estimated by dividing the remaining life of the last rehabilitation treatment, by the expected life of the treatment. Service Life − Activity Age Service Life To determine the residual value, the last major rehabilitation activity is used. Based on the year of implementation of the last rehabilitation, the expected service life (from the Unit Costs table) and the activity cost, a proportion of the initial cost is estimated. This residual value at the end of the design period is then converted (discounted) to a net present value. That net present value is then subtracted from the other costs. Residual Value = M&R Cost
Most municipalities in Canada specify the types and composition of the initial pavement structure which is then built by the developer with ownership and maintenance assumed by the City. The initial pavement costs are borne by the developer and eventually ownership of the pavement and the responsibility to maintain that pavement is transferred to the ultimate owner of the property/development, typically the municipality. The intention of this report is not to compare total life-cycle cost including initial construction and future maintenance and rehabilitation costs but rather only the future costs of maintenance and rehabilitation. Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison The maintenance and rehabilitation plans outlined above were used in conjunction with typical municipal costs and a discount rate of 4 percent to develop the comparison of roadway/ parking area maintenance and rehabilitation costs shown in Table 11 and in Figure 3. The life- 17 -
cycle cost differences are compared relative to conventional AC over an aggregate base which is the most common roadway/parking area pavement type used by municipalities in Canada. Table 11. Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison. Item M&R Cost (Base Year) M&R Cost (Discounted) LCC Difference Compared to AC/Aggregate Base
ICP/Aggregate $ 211,650 $ 77,023
Roadway Surface/Base ICP/Concrete AC/Aggregate PCC/Aggregate
$ $
-19 %
361,650 114,281
$ $
282,125 94,800
21 %
$ $
230,750 70,253 -26 %
Figure 3. Roadway/Parking Area Maintenance and Rehabilitation Cost Comparison.
Based on the calculations above, the 50-year life-cycle maintenance costs for ICP on an aggregate base are 19 percent lower than for AC on an aggregate base. The life-cycle maintenance costs for ICP on a concrete base are 21 percent higher than for AC on an aggregate base. The life-cycle maintenance costs for PCC on an aggregate base are 26 percent less than for AC on an aggregate base. The higher cost for ICP on a concrete base is primarily due to the cost of concrete slab replacements. Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison The maintenance and rehabilitation plans outlined above are characterized with typical municipal costs and a discount rate of 4 percent to develop the comparison of sidewalk/ recreational trail maintenance and rehabilitation costs shown in Table 12 and Figure 4. The life-cycle cost differences are compared relative to conventional PCC over an aggregate base which is the most common sidewalk pavement type used by municipalities in Canada.
- 18 -
Table 12. Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison. Item M&R Cost (Base Year) M&R Cost (Discounted) LCC Difference Compared to PCC/Aggregate Base
Sidewalk Surface/Base
ICP/Aggregate $ $
4,918 2,008 -52 %
ICP/Concrete $ $
9,225 3,901 -6 %
AC/Aggregate $ $
3,874 1,543
PCC/Aggregate $ 10,519 $ 4,151
-63 %
Figure 4. Sidewalk/Recreational Trail Maintenance and Rehabilitation Cost Comparison. Based on the calculations above, the 40-year maintenance and operations costs for ICP on an aggregate base are 52 percent less than for PCC on an aggregate base. The life-cycle maintenance and operation costs for ICP on a concrete base are 6 percent lower than for PCC on an aggregate base. For AC on aggregate base the cost is 63 percent lower compared to PCC on an aggregate base. The higher costs for PCC on an aggregate base and ICP on a concrete base are primarily due to the cost of concrete slab replacements and undersealing to address settlements and distortions.
Conclusions The maintenance and rehabilitation life-cycle cost analysis presented in this report is typical for municipal low volume roads/parking areas and sidewalks/recreational trail pavements in Canada. While road/parking areas and sidewalks/recreational trail pavement cross sections will vary based on the intended traffic and subgrade conditions, they are designed for these elements. Future maintenance and rehabilitation needs will be similar for the cross sections of each pavement type. The results of the analysis for the low volume road/parking area pavements, when comparing to the typically used asphalt concrete pavement, shows the overall life-cycle maintenance cost - 19 -
of 1) interlocking concrete pavement with a concrete base is more expensive (21 %), 2) interlocking concrete pavement on a gravel base is significantly less expense (19 %) and, 3) Portland cement concrete pavement is the lowest cost option. The results of the analysis for the sidewalk/recreational trail pavements, when comparing to the typically used Portland cement concrete sidewalk shows the overall life-cycle maintenance cost of 1) interlocking concrete pavement on an aggregate base is significantly less expensive than Portland cement concrete (52 %), 2) asphalt concrete pavement has an even lower lifecycle maintenance cost compared to Portland cement concrete sidewalk (63 %) and, 3) interlocking concrete pavement on a concrete base has a life-cycle maintenance cost very similar to that of Portland cement concrete. Regardless of the pavement type, the adoption of a regular maintenance and pavement preservation plan is critical in achieving cost-effective sustainable transportation infrastructure. The decision to use life-cycle cost analysis and evaluate sustainable benefits including noneconomic factors as part of the pavement type selection process provides government agencies with better knowledge of future maintenance and rehabilitation costs of pavement rather than just considering the initial cost of the pavement.
Closure The author of this document reserves the right to supplement this report with additional comments to the extent further information may be come available. Prepared and Submitted by: 2737493 Ontario Limited
David K. Hein, P. Eng. Principal Engineer
- 20 -
Appendix A
Life-Cycle Cost Details Low Volume Roads/Parking Areas
- A1 -
Municipal Road Pavements LIFE-CYCLE MAINTENANCE AND REHABILITATION ANALYSIS SUMMARY
Item
ICP (Aggregate Base) ICP (Concrete Base)
M&R Cost 2021 Dollars M&R Cost (Discounted) LCC Difference to AC (Aggregate Base), %
$ $
211,650 $ 77,023 $ -18.8
AC (Aggregate Base) PCC (Aggregate Base)
361,650 $ 114,281 $ 20.5
282,125 $ 94,800 $ 0.0
Life-Cycle M&R Cost Comparison ($/2-lane km) Low Volume Road/Parking Area
50 Year Life-Cycle Cost
$120,000 $100,000 $80,000 $60,000 $40,000 $20,000 $ICP (Aggregate Base)
ICP (Concrete Base)
AC (Aggregate Base)
- A2 -
PCC (Aggregate Base)
230,750 70,253 -25.9
- A3 -
Road Class
Municpal Local Collector (ICP)
Subgrade
40 MPa (CBR = 4)
All quantities and costs are for one km of 2-lane roadway Pavement Design
Geometric Design
80 mm Paver
Design feature
25 mm Bedding Sand
Width of the traffic lanes, m
Dimension 7.5
165 mm Portland Cement Concrete
Total width of paved shoulders, m
N/A
300 mm Granular Base
Total width of subject road, m
7.5 1000
Length of section
Urban Pavement Maintenance and Rehabilitation Action Plan Years after initial construction 8
Description of pavement layer, Amount (Quantity)
Amount
Quantity
Price per Net present unit of Cost worth quantity $ 55.00 $ 8,250 $ 6,028
Reset pavers, % area (m2)
2
150
18
Replace cracked pavers, % area (m2)
5
375 $
18
Reset pavers, % area (m2)
5
375
18
Joint sand replenishment % area (m2)
5
375 $
5.00 $
28
Full depth PCC repair, % area (m2)
5
375 $
150.00 $
28
Replace cracked pavers, % area (m2)
2
150 $
120.00 $
18,000 $
6,003
28
Reset pavers, % area (m2)
5
375
55.00 $
20,625 $
6,878
28
Joint sand replenishment % area (m2)
10
750 $
5.00 $
3,750 $
1,251
38
Full depth PCC repair, % area (m2)
10
750 $
150.00
$ 112,500 $
25,345
38
Replace cracked pavers, % area (m2)
5
375 $
38
Reset pavers, % area (m2)
5
375
38
Joint sand replenishment % area (m2)
48
Replace cracked pavers, % area (m2)
50
Residual value Total Maintenance and Rehabilitation Cost
- A4 -
$
$
120.00 $
45,000 $
22,213
55.00 $
20,625 $
10,181
$
926
56,250 $
1,875
18,758
120.00 $
45,000 $
10,138
$
55.00 $
20,625 $
4,647
10
750 $
5.00 $
3
225 $
3,750
$
845
120.00 $
27,000 $
4,109
$
21,600 $
3,039
$ 361,650
$ 114,281
- A5 -
Road Class
Municipal Local Collector (PCC)
Subgrade
40 MPa (CBR = 4)
All quantities and costs are for one km of 2-lane roadway Pavement Design
Geometric Design
170 mm PCC
Design feature
200 mm Granular Base
Width of the traffic lanes, m
7.5
Total width of paved shoulders, m
N/A
No Dowels
Dimension
Total width of subject road, m
4 m Slab Length
7.5
Length of section
Tied Shoulder/Curb
1000
Urban Pavement Maintenance and Rehabilitation Action Plan Years after initial construction 12
Description of pavement layer, Amount (Quantity)
Amount
Reseal joints, % Length (m)
Quantity
20
375
Price per Net present unit of Cost worth quantity $ 12.00 $ 4,500 $ 2,811
25
Partial depth PCC repair, % area (m²)
2
150 $
200.00 $
30,000 $
11,254
25
Full depth PCC repair, % area (m2)
5
375 $
150.00 $
56,250 $
21,100
25
Reseal joints, % Length (m)
$
12.00 $
9,000 $
3,376
40
Partial depth PCC repair, % area (m²)
5
375 $
200.00 $
75,000 $
15,622
40
Full depth PCC repair, % area (m2)
10
750 $
150.00
$ 112,500 $
23,433
40
Reseal joints, % Length (m)
40
750
50
Residual Value
40
Total Maintenance and Rehabilitation Cost
- A6 -
750
$
12.00 $
9,000 $
1,875
$
65,500 $
9,217
$ 230,750
$
70,253
Appendix B
Life-Cycle Cost Details Sidewalks and Recreational Trails
- B1 -
Municipal Sidewalk/Trail Pavements LIFE-CYCLE MAINTENANCE AND REHABILITATION ANALYSIS SUMMARY Item
ICP (Aggregate Base) ICP (Concrete Base)
M&R Cost 2021 Dollars M&R Cost (Discounted) LCC Difference to PCC (Aggregate Base), %
$ $
4,984 $ 2,008 $ -51.6%
AC (Aggregate Base) PCC (Aggregate Base)
9,225 $ 3,901 $ -6.0%
3,874 $ 1,543 $ -62.8%
Life-Cycle M&R Cost Comparison ($/100 m) Sidewalks/Recreational Trails 40 Year Life-cycle Cost
$4,500 $4,000 $3,500 $3,000 $2,500 $2,000 $1,500 $1,000 $500 $0 ICP (Aggregate Base)
ICP (Concrete Base)
AC (Aggregate Base)
- B2 -
PCC (Aggregate Base)
10,519 4,151 0.0%
Sidewalk
Pavers
Width
1.5
Length
100
Sidewalk Design 105 Paver 150 Granular Base 150 Granular Subbase
Maintenance Action Plan Years after initial construction 10
Description of pavement layer, Amount (Quantity)
Amount
Quantity
Price per unit of quantity $ 55.00
Net present worth
Cost
Reset Pavers (m²)
5
8
15
Replace Cracked or Damaged Pavers (m²)
3
5 $
15
Joint Sand Replenishment (m²)
5
8 $
20
Reset Pavers (m²)
15
23
25
Joint Sand Replenishment (m²)
15
23 $
30
Reset Pavers (m²)
15
23
$
55.00 $
1,238
$
382
35
Replace Cracked or Damaged Pavers (m²)
15
23 $
120.00 $
2,700
35
Joint Sand Replenishment (m²)
15
23 $
5.00
40
120.00
$
413
$
279
$
540
$
300
5.00 $
$
55.00 $ 5.00
$
1,238
$
113 $
21 565 42
$
684
$
113 $
29
0
$
- $
- $
-
0
$
- $
- $
-
0
$
- $
- $
-
0
$
- $
- $
-
0
$
- $
- $
Residual Value
$
Total Maintenance and Rehabilitation Cost Cost/m²
- B3 -
38 $
1,406
$
293
$
4,984
$
2,008
$
33.23
$
13.38
Sidewalk
Pavers
Width
1.5
Length
100
Sidewalk Design 105 Paver 100 Portland Cement Concrete 150 Granular Base
Maintenance Action Plan Years after initial construction 10
Slab Jacking (m²)
5
10
Reset Pavers (m²)
5
15
Slab Jacking (m²)
15
Reset Pavers (m²)
25
Concrete Panel Replacement (m²)
25
Slab Jacking (m²)
10
15
$
25
Reset Pavers (m²)
10
15
$
55.00
35
Concrete Panel Replacement (m²)
10
15 $
225.00 $
3,375
$
855
35
Slab Jacking (m²)
10
15
$
75.00 $
1,125
$
285
35
Reset Pavers (m²)
10
15
$
55.00
825
40
Description of pavement layer, Amount (Quantity)
8
Price per unit of quantity $ 75.00
$
563
$
380
8
$
55.00
$
413
$
279
10
15
$
75.00 $
1,125
$
625
10
15
$
55.00
$
825
$
458
225.00 $
1,688
$
633
75.00 $
1,125
$
422
825
$
309
Amount
Quantity
5
8 $
$
$
209
0
$
- $
- $
-
0
$
- $
- $
-
0
$
- $
- $
Residual Value
$
$
Total Maintenance and Rehabilitation Cost Cost/m²
- B4 -
Net present worth
Cost
2,663
$
555
$
9,225
$
3,901
$
61.50
$
26.01
Sidewalk
Asphalt Concrete
Width
1.5
Length
100
Sidewalk Design 100 mm Asphalt Concrete 150 mm Granular Base 150 mm Granular Subbase
Maintenance Action Plan Years after initial construction 10
Description of pavement layer, Amount (Quantity) Rout and Seal Asphalt (m)
10
Spot Repairs, Mill and Patch (m2)
20
Mill AC, (mm/m2)
20 25 30
Spot Repairs, Mill and Patch (m2)
35
Mill AC, (mm/m2)
35
Full-Depth Asphalt Base Repair, % Area (m2)
35 40
40
Amount
Price per Net present unit of Cost worth quantity 7.5 $ 5.00 $ 38 $ 25
Quantity
7.5 2
3.0
$
35.00
$
105 $
40
6000.0 $
0.05
$
300
$
137
Resurface with Surface Course Asphalt, (mm/m2)
40
6000.0 $
0.30 $
1,800
$
821
Rout and Seal Asphalt (m)
15
15.0 $
5.00 $
$
$
75 $
28
263 $
81
5
7.5
40
6000.0 $
0.05
$
300 $
76
5
7.5
45.00
$
338 $
86
Resurface with Surface Course Asphalt, (mm/m2)
40
6000.0 $
0.30 $
$
456
Rout and Seal Asphalt (m)
15
15.0 $
5.00 $
75 $
16
$
35.00
71
0.0
$
- $
- $
-
0.0
$
- $
- $
-
0.0
$
- $
- $
Residual Value
$
Total Maintenance and Rehabilitation Cost Cost/m²
- B5 -
1,800
1,219
$
254
$
3,874
$
1,543
$
25.83
$
10.29
Sidewalk
Concrete
Width
1.5
Length
100
Sidewalk Design 125 mm Concrete 150 mm Granular Base
Maintenance Action Plan Years after initial construction 10
Slab Jacking (m²)
5
7.5
Price per unit of quantity $ 75.00
$
563
$
380
10
Concrete Edge Grinding (per 1-1.5 m)
5
7.5
$
30.00
$
225
$
152
15
Slab Jacking (m²)
5
7.5
$
75.00
$
563
$
312
15
Concrete Edge Grinding (per 1-1.5 m)
15
22.5
$
30.00
$
675
$
375
25
Concrete Panel Replacement (m²)
10
15.0 $
3,375 $
1,266
25
Slab Jacking (m²)
10
15.0
$
75.00 $
25
Concrete Edge Grinding (per 1-1.5 m)
15
22.5
$
30.00
35
Concrete Panel Replacement (m²)
15
22.5 $
35
Slab Jacking (m²)
10
15.0
$
75.00 $
35
Concrete Edge Grinding (per 1-1.5 m)
10
15.0
$
30.00
40
Description of pavement layer, Amount (Quantity)
Amount
Quantity
225.00 $ $
225.00 $ $
1,125
$
422
675
$
253
5,063 $
1,283
1,125
$
285
450
$
114
0.0
$
- $
- $
-
0.0
$
- $
- $
-
0.0
$
- $
- $
-
0.0
$
- $
- $
Residual Value
$
Total Maintenance and Rehabilitation Cost Cost/m²
- B6 -
Net present worth
Cost
3,319
$
691
$
10,519
$
4,151
$
70.13
$
27.67
August 11, 2021
Interlocking Concrete Pavement Institute 14801 Murdock Street, Suite 230 Chantilly, Virginia 20151 Attention: Mr. Robert Bowers
Subject: Peer Review of “Comparison of Life-Cycle Maintenance and Rehabilitation Costs for Typical Pavement Systems” 04-02107794.000-IM-0-L-0001-0A
Dear Sir:
Englobe is pleased to review the report titled “Comparison of Life-Cycle Maintenance and Rehabilitation Costs for Typical Pavement Systems” dated June 4, 2021. The intent for the report is to evaluate the life cycle costs (LCCA) for the maintenance portion of the asset. Initial cost was not considered due to the initial cost being absorbed by the developer. The report is evaluating the costs relevant to the owner after turnover from a developer. The report follows standard LCCA principles as described in Ministry of Transportation of Ontario, “Guidelines for the Use of Life Cycle Cost Analysis on MTO Freeway Projects”. The discount rate used was 4 percent which is in the normal range. Overall, the report is based on well established principles and can be reproduced by an owner using their local cost data. Comments below are additional highlights of important information provided in the report or reflections on costs provided. Comments: •
Pavement cross-sections are standard sections used in some municipalities in Ontario. These sections, as indicated in the report, are thicker than required such that fatigue is not a concern in the LCCA. Fatigue damage is not normally the driver for low volume roads, trails and sidewalks, usually environmental effects are the primary drivers. The maintenance schedule reflects this.
Englobe Corp.
T 519.685.6400 F 519.685.0943 london@englobecorp.com
Unit 12 – 60 Meg Drive London (Ontario) N6E 3T6 Canada
Subject : Peer Review of “Comparison of Life-Cycle Maintenance and Rehabilitation Costs for Typical Pavement Systems” 04-02107794.000-IM-0-L-0001-0A
August 11, 2021
•
The cost for partial depth repair is based off a 2011 study. The expectation would be some inflationary increases for this item. Some agencies are moving away from partial depth repairs since they are costly in comparison to full depth PCC repair.
•
Cost for full depth repair is based on a 2011 study, the expectation would be some inflationary increases.
We trust the enclosed is to your satisfaction. If, additional information should be required, please communicate with the undersigned. Yours very truly, Englobe Corp.
Mick Prieur, P.Eng, PMP Director – Geotechnical and Materials Engineering-SWO MP
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