Co-pending application (COE-871A) filed on the same day as this application and incorporated by reference in its entirety contains detailed information on determining estimated uniform annual cost with and without global M&R at time teval; localized cost component of estimated uniform annual cost for Global and Major M&R; and estimated uniform annual cost with and without major M&R at time teval. COE-871A also contains detailed information on the algorithm and method to resolve EUACS
Co-pending application (COE-871B) filed on the same day as this application and incorporated by reference in its entirety contains detailed information on the algorithm and method to determine critical PCI for a PCI using major ROI calculations.
This invention relates to systems and methods for repairing pavement.
Airfield and roadway pavements are deteriorating faster than they are being repaired. In the past, pavements were maintained but not managed, and little regard was given either to life cycle costing or to priority, as compared to other requirements. Letting pavements deteriorate without preventive maintenance is very costly and results in an increased backlog and eventually a loss of assets. As pavement infrastructure has proliferated and aged, a more systematic approach to determining maintenance and repair (M&R) needs and priorities became necessary. Optimum timing of repairs results in improved pavement condition and considerable cost savings over the life of the system. If M&R is performed during the early stages of deterioration, i.e., before the sharp decline in pavement condition, over 50% of lifecycle repair costs are saved. In addition to cost reduction, long periods of closure to traffic and detours can be avoided.
PCI (pavement condition index) provides both a numerical and a “qualitative” estimate of pavement condition on a scale. PCI allows pavement M&R managers to use and create other condition indices. Qualitative ranges for PCI may be customized and used for reporting analysis results in accordance with user requirements. Manuals for roads and airfields show defect type, severity level definitions, and guidelines for the measuring criteria used by inspectors.
Prior art interfaces exist for importing inspection data from automated collection resources such as those that may be affixed to a vehicle traveling over the target pavement section(s). Select embodiments of the present invention provide users a prior art interface for recording the results of an inspection and an online user's guide for selecting the type of distress and assigning a severity thereto, thereby facilitating the assessment of all pavement distresses on each pavement section.
The following materials and patents provide background information on the invention.
Aspects of the invention may relate to a pavement management application (PMA) computer comprising a processor and tangible memory storing non-transitory computer readable software configured to cause the processor to execute a pavement repair program specialized in determining calculating EUACSw(teval) (estimated uniform annual cost per unit area for S when performing work (w) of a particular category at time/age teval) and EUACSwo(teval) (estimated uniform annual cost per unit area for S without (wo) performing work of a particular category on S at time/age teval) for localized preventive M&R when the PCI family was built with preventive maintenance.
The program may comprise an input interface configured to allow a user to specify to the program: a Section of pavement for evaluation(S); a PCI family (PF) assigned to Section(S) defined as PFS; wherein PCI is a pavement condition index of the Section; a PCIcrit defined as a critical for PFS; a M&R family (MFS) assigned to S; an inspection history (IHS) for S; a work history (WHS) for S; a tii defined as an age of last inspection prior to any global work on S; ΔTS defined as a lifespan loss not doing preventive maintenance on S; a work plan start (tWP); a time of evaluation (teval); a work-planned work WPS(teval) for S before (teval); and a work-plan predicted conditions (CS(teval)) for S up to teval.
The program may comprise a EUAC calculator configured to use: Common$, the sum of global work cost up to teval (G$before), localized work costs before work planning (L$pre1), localized work costs from work plan start to teval (L$pre2), and a cost for major at PCIcrit (Major$crit) to determine EUACSwo and EUACSw.
The program may comprise a global cost calculator configured to calculate G$before. Additionally, the program may comprise a calculator configured to: determine localized costs before a workplan starts (L$pre1) from conditions by using the family curve shifted based on inspection and work history at each time t from 0 to tWP−1 to determine a condition at time t of the Section S, and using MFS to get the appropriate localized cost. The appropriate localized cost may be a preventive maintenance cost when the condition of the Section is above or equal to critical. The appropriate localized cost may be a safety maintenance cost when the condition of the Section is below critical. The work plan results (WPS(teval)) may comprise localized costs L$pre2. The program may comprise a calculator configured to calculate Major$crit; calculate inputs for EUACSw(teval) using a family curve for families built with preventative maintenance; and calculate inputs for EUACSwo(teval) using a family curve for families built without preventative maintenance.
Aspects of the invention may relate to a pavement management application (PMA) computer comprising a processor and tangible memory storing non-transitory computer readable software configured to cause the processor to execute a pavement repair program specialized in determining calculating EUACSw(teval) and EUACSwo(teval) for localized preventive M&R when the PCI family was built without preventive maintenance.
The program may comprise an input interface configured to allow a user to specify to the program: a Section of pavement for evaluation (S); a PCI family (PF) assigned to Section (S) defined as PFS; wherein PCI is a pavement condition index of the Section; an input estimated critical PCI (PCIcrit) for PFS; a PCIcrit defined as a critical for PFS; a M&R family (MFS) assigned to S; an inspection history (IHS) for S; a work history (WHS) for S; a tii defined as an age of last inspection prior to any global work on S; ΔTS defined as a lifespan gain for doing preventative maintenance on S; a work plan start (tWP); a time of evaluation (teval); a work-planned work for S before (teval); and a work-plan predicted conditions (CS(teval)) for S up to teval.
The program may comprise a EUAC calculator configured to use: Common$, the sum of global work cost up to teval (G$before), localized safety costs before work planning (L$pre1), localized work costs from work plan start to teval (L$pre2), and a cost for major at PCIcrit (Major$crit) to determine EUACSwo and EUACSw.
The program may comprise a global cost calculator configured to calculate G$before. The calculator may be configured to determine localized costs before a workplan starts (L$pre1) from conditions by using the family curve shifted based on inspection and work history at each time t from 0 to tWP−1 to determine the condition at time t, and using MR to get the appropriate localized safety cost at that condition cost; the work plan results (WPS(teval)) comprising localized costs L$pre2. The calculator may be configured to calculate Major$crit; and calculate inputs for EUACSwo(teval) using a family curve for families built with preventative maintenance.
The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
Risk Cost (RC) and Return-On-Investment (ROI) provide useful data points for making investment decisions. These measures may be adapted to areas of application like pavement infrastructure maintenance management to be meaningful in those areas. For example, certain configurations of the invention provide methods and algorithms to determine an “estimated uniform annual cost” of a repairing and maintaining pavement section. Various equations can be used to facilitate estimations of costs and return-on-investments for maintenance and repair (M&R). The pavement management application (PMA), a specialized computer running the pavement management application (PMA) software, may be configured to apply RC and ROI to pavement maintenance activities.
PMA may be designed to make calculations of RC and ROI more accurate by considering pavement models (“families”). Use of pavement models may provide a more accurate outcome than, for example, using a linear-decay model or uniform pavement repair costs. PMA may be configured to calculate RC and ROI more accurately by including historical data about the particular pavement section being evaluated. PMA may be configured to make the RC and ROI numbers more usable by integrating these numbers into existing maintenance planning tools such as a section M&R Computer, Section Maintenance and/or Repair System, and/or an Inspection system.
PMA may be configured to resolve the pavement maintenance management question “what is the most economically effective maintenance and repair (M&R) actions to perform on my pavement infrastructure?” PMA may be configured to manage a pavement repair calendar for a small network of roads (like a gated community), a military base, a city or county, or even an entire country of roads.
PMA may be configured to calculate estimated uniform annual cost (EUAC) of global, major and localized preventive M&R at a particular point in time, based on both pavement condition family and section history in which the pavement condition family may be adjusted based on historical work and inspections. The pavement condition family may be adjusted based on already planned work. The adjusted pavement condition family may be used to calculate the EUAC both when performing and not performing the particular type of M&R under consideration.
For localized preventive M&R, the method of calculating EUAC may be varied depending on (a) whether the pavement condition family was built including or not including preventive M&R, and (b) whether a work planning method is including localized preventive M&R or not.
PMA may be configured to determine a localized cost component of EUAC for Major M&R in which: the cost calculation may be adjusted based on whether the condition family is built with or without preventive M&R. The cost calculation may be adjusted based on whether the work planning method includes localized preventive M&R or not. The cost calculation may be adjusted based on whether the current estimated condition of the section is above or below the critical condition.
PMA may be configured to determine the critical condition for a condition family that employs an iterative algorithm to determine the PCI at which Major M&R has a maximum ROI and in which an initial estimated critical PCI may be used to begin the iteration. The ROI for major M&R may be calculated at each condition value using the configurations described above, and the maximum of which is used as the next estimate of critical PCI. The final estimated critical PCI may be the value at which the iteration stabilizes.
PMA may be configured to determine an effect of localized preventive M&R on a section's life that employs an iterative algorithm. The algorithm may be used either for estimating the life gain for doing preventive work on a section whose condition family does not include preventive, or for estimating the life loss for not doing preventive work on a section whose condition family does include preventive. PMA may generate an estimate of life gain/loss for a pavement with a twenty-year life is adjusted appropriately to estimate the life gain/loss for a particular pavement. PMA may adjust the algorithm based on the inspection and work history of the section by shifting the pavement condition family appropriately, then calculating an annual age adjustment needed to determine a proportionality factor to apply to a twenty-year life effect.
There may be three categories of M&R; Localized (spot maintenance such as patching or crack sealing), Global (pavement preservation by applying different types of seal coats to eth entire pavement surface), and Major (such as pavement overlay or reconstruction to bring the pavement to new condition). The RC and ROI methods for each of these categories are different and are included in this disclosure.
PMA may comprise a repair priority logic configured to: prioritize repairs into three priority categories: low priority repairs, medium priority repairs, and high priority repairs; determine a repair priority for each of the pavements within a user's network; and adjust the repair priority of the pavements to maximize a user's return-on-investment.
PMA may comprise a return-on-investment calculator configured to prioritize different types of repairs as high, medium, and low priority. The return-on-investment calculator may be configured to set and modify these priorities to maximize a user's budget. The software can determine which roads should be repaired first and what kind of repairs should be made. The software may be configured to analyze all the possibilities a user has (e.g., what types of equipment for repairs) and provide the user with recommendations as to which repairs to make. return-on-investment calculator may be configured to forecast deterioration of roads if repairs are not made. The return-on-investment calculator may be configured to calculate an ROI for each section of each road in a network of roads. The return-on-investment calculator may include in its calculations, costs associated with making repairs versus costs of not making repairs.
PMA may comprise a pavement condition prediction engine. The pavement condition prediction engine may contain algorithms that analyze and predict pavement deterioration based on pavement type, pavement families, repair history, and deterioration history. The pavement condition prediction engine may be configured to perform this analysis on a pavement section level based on the actual history of that section of the road. The pavement condition prediction engine may be configured to determine a cost curve for repairs for a pavement section and determine an exact point in time where repair costs get much more expensive. This point is known as the PCI Pavement Condition Index.
PMA may comprise budget & reports generation module (also referred to as a results module). The budget & reports module may be configured to optimize a user's budget if the software is given a budget to spend over the course of several years. The budget & reports module may be configured to generate a budget to maintain road condition (as specified by the user) at or above a certain pavement quality. The budget & reports module may be configured to generate various reports that contain recommendations on what roads to repair and how to repair them over a course of time (e.g., a 5-year plan.) The budget & reports module may be configured to generate digital color code maps to aid the user in understanding what roads to repair and what their roads will look like if roads are not repaired.
S: refers to a specific pavement section on which PMA may be configured to determine M&R risk cost and return-on-investments. In some configurations, critical properties of S such as its surface type and its area (AreaS) are known.
PF: refers to a PCI family. PMA may assign a PCI family to a Section under consideration or evaluation. A PCI family may comprise three properties. One, a deterioration curve from pavement age to pavement condition. Two, PCIcrit: a critical PCI value for the family. The critical PCI value may be the value below which global and localized preventive M&R (pavement preservation) are no longer performed, and safety M&R begins. Three, whether the deterioration curve is based on sections that have had localized preventive M&R performed.
PFS(t) refers to the PCI family PMA may have assigned to a section S after PMA has made adjustments based on section history or predicted condition up to time age t. Specifically, PMA may shift the deterioration curve for the family on the time axis so that the curve passes through a particularly observed (in the case of inspection) or calculated (in the case of global work or working planning) age×condition pair. It's possible that at different points in time t, the curve shift will be different, typically based on the latest work, inspection, or condition prediction prior to t.
MF: refers to an M&R family. PMA may assign an M&R family to a Section under consideration. The M&R family may have six properties. One, a cost curve from PCI to localized preventive M&R cost per unit area. Two, a cost curve from PCI to localized safety M&R cost per unit area. Three, a cost curve from PCI to major M&R cost per unit area. Four, the specific types of global work to perform for minimal, climate-related and skid-causing distresses. Five, a cost table specific global work type to cost per unit area. Six, the PCI at which sections in this M&R family are typically reconstructed (PCIrecon).
IHS: refers to the inspection history for S. PMA may use each inspection in the section's history to identify the date, the age of the pavement at the time of inspection and its PCI value (based on observed distresses).
WHS: refers to the work history of S. The work history of S may include the dates when the section received major or global M&R.
teval: refers to the date at which PMA computes estimated uniform annual cost.
TSw(teval): refers to the lifetime of section S from last Major M&R to PCIcrit when work of a particular category of M&R is performed by a third party on S at teval.
tWP: refers to the date at which M&R work planning begins.
PMA may be configured to integrate risk and ROI calculations into pavement work planning. PMA may be configured to use a work planning method incorporating PCI families assigned to a Section to estimate the Section condition in future years. The work planning method may include an algorithm for determining what work to do in which year. The work planning method may utilize the M&R work family assigned to the Section to estimate work costs for each plan year. The work planning method may be configured such that PMA can produce the following two outputs: WPS(teval): refers to work the work planner has planned for S from tWP to teval−1 and CS(teval): refers to the conditions the work planner has predicted for S from tWP to teval.
PMA may be configured with a date conversion module. The date conversion module may be configured to allow PMA to convert a Section's date (such as teval) to a Section's age at that date. The date conversion module may utilize the information in the Section's work history WHS to convert between Section data and Section age at that date. Throughout the application, date and ages are generally expressed in terms of fractional years, so an expression such as teval−1 means “one year before the date/age given by teval.”
PMA may be programmed to use the above elements to determine risk cost and return-on-investment.
EUACSw(teval): refers to an estimated uniform annual cost per unit area for S when performing work (w) of a particular category at time/age teval.
EUACSwo(teval): refers to an estimated uniform annual cost per unit area for S without (wo) performing work of a particular category on S at time/age teval.
ΔEUACS(teval)=EUACSwo(teval)−EUACSw(teval): refers to the change in estimated uniform annual cost per unit area between doing work and not doing work of a particular category on S at time/age teval.
refers to a return-on-investment for performing work of a particular category on S at teval.
RCS (teval)=ΔEUACS(teval)×AreaS is the annual risk cost for performing work of a particular type on S at teval. This is definition of risk cost based on estimated uniform annual cost includes a multiplier by section area. Since EUAC is expressed in terms of unit area, PMA may be configured to multiply the EUAC by the area of S to resolve risk cost.
PMA may be configured to use the equations for ΔEUAC, ROI and RC to accurately determine EUACSw(teval) and EUACSwo(teval) for a particular work category for a pavement section S at time/age teval.
PMA may be configured to determine methods for each of three M&R categories: Global M&R, Localized Preventive and Major.
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To determine these costs, PMA may utilize certain input information and determine certain costs in performing the calculations. Co-pending application (COE-871B) contains detailed information on the algorithm and method to determine critical PCI for a PCI using major ROI calculations.
Localized Preventive M&R—Family Built with Preventive
PMA may be configured to determine both EUACSwo and EUACSw, by determining Common$, the sum of global work cost up to teval (G$before), localized work costs before work planning (L$pre1), localized work costs from work plan start to teval (L$pre2) and the cost for major at PCIcrit (Major$crit) (steps 6A.2 and 6A.3). PMA may determine global cost G$before using a sum of two elements. One, PMA may set G$pre as the cost of actual global work recorded in the section work history WHS(6A.1.1.1) Two, PMA may determine global work directly as it may be included in work plan results WPS(teval) before teval (6A. 1.1.1).
PMA may be configured to calculate localized costs before the workplan starts (L$pre1) from conditions by using the family curve shifted based on inspection and work history at each time t from 0 to twp−1 to determine the condition at time t, and using MR to get the appropriate localized cost (preventive if the condition is above critical, safety otherwise) (6A.1).
PMA may be configured to obtain localized costs L$pre2 from workplan start to teval by accessing details within the work plan which are in WPS(teval) (6A.1). PMA may be configured to calculate Major$crit. For families built with preventive, PMA may be configured to use the family curve to calculate the inputs for EUACSw(teval). PMA may be configured to use PFS(teval) to calculate TSw(teval) and the conditions Cw from teval+1 to TSw(teval) (6A.2.1). PMA may be configured to determine the localized cost term L$w using the preventive cost curve in MF (6A.2.2).
For families built with preventive, PMA may be configured to determine TSwo(teval) (the lifespan of S without doing preventive on or after teval) and L$wo (the cost for localized work from teval to TSwo(teval)). PMA may be configured to use PFS(tli), the family curve shifted to pass through the last pre-global-work inspection before tWP, to calculate TSw, the life of S with preventive (6A.3.1). PMA may be configured to use TSw to calculate ΔtS(tli), the life loss for S at tli as the fraction of ΔTS that applies at tli. PMA may be configured to resolve TSwo(tli), the lifespan loss for not doing preventive on S after tli (6A.3.1). PMA may be configured to calculate an annual age increase Δa as ΔtS(tli) divided by the interval from tli to TSwo(tli). PMA may be configured to use PFS(teval) (the family curve shifted to pass through the workplan calculated condition at teval) and Δa to calculate conditions after teval. PMA may be configured to perform this operation by using PFS(teval) for years i=1, 2, . . . , n after teval until the calculated condition at age teval+n Δa is below PCIcrit. PMA may resolve TSwo(teval) by solving the equation TSwo(teval)=teval+(n−1) and the conditions Cwo are those from teval to TSwo(teval). PMA can use the safety cost curve of MF to compute L$wo and finally EUACSwo(teval) when PMA has already resolved Cwo (6A.3.4).
Localized Preventive M&R—Family Built without Preventive
PMA may be configured to determine Global cost G$before by summing two elements. One, PMA may determine G$pre as the cost of actual global work recorded in the section work history WHS. Two, PMA may determine global work included in work plan results WPS(teval) before teval (7A.1.1.1).
PMA may be configured to calculate localized costs before the workplan starts (L$pre1) from conditions by using the family curve shifted based on inspection and work history at each time t from 0 to tWP−1 to determine the condition at time t, and using MR to get the localized safety cost at that condition (just safety costs are used because the family model is without preventive) (7A.1.2). PMA may be configured to resolve localized costs L$pre2 from workplan start to teval from the work plan at WPS(teval). PMA may calculate Major$crit by using MF. For example, PMA can determine Major$crit directly from PCIcrit and the major M&R cost curve in MF (7A.1.3).
For families built without preventive, PMA may be configured to use the family curve to calculate the inputs for EUACSwo(teval). PMA may be configured to use PFS(teval) to directly calculate TSwo(teval) and the conditions Cwo from teval+1 to TSwo(teval) (7A.2.2). PMA may be configured to determine the localized cost term L$w using the appropriate cost curve in MF; when the PCI is above critical this will be the preventive cost, and when the PCI is below critical it will be the safety cost.
For families built without preventive, PMA may be configured to determine TSw (the life of S when doing preventive on and after tWP) and L$w (the cost for localized work from teval to TSw). PMA may be configured to use PFS(tli), the family curve shifted to pass through the last pre-global-work inspection before tWP, to calculate TSwo, the life of S without preventive. PMA may use TSwo to calculate ΔtS(tli) the life gain for S at tli as the fraction of ΔTS that applies at tli (7A.3.1). PMA may resolve TSw(tli), the life gain for doing preventive on S after tli. PMA may be configured to calculate the annual age decrease Δa as ΔtS(tli) divided by the interval from tli to TSw(tli) (7A.3.2). PMA may be configured to use PFS(teval) (the family curve shifted to pass through the workplan calculated condition at teval) and Δa to calculate conditions after teval (7A.3.3). PMA may perform these calculations using PFS(teval) for years i=1, 2, . . . , n after teval until the calculated condition at age teval+n Δa is below PCIcrit. PMA may determine TSw(teval) using the equation TSw(teval)=teval+(n−1) and the conditions Cw are those from teval to TSwo(teval). PMA may be configured to use the preventive cost curve of MF to compute L$w and finally EUACSw(teval) when Cw has been resolved (7A.3.4).
Localized Preventive M&R—Work Planning without Preventive
The previous two sub-sections specified algorithms and methods for calculating estimated uniform annual cost for preventive work when planning work. These algorithms/methods may presume that work planning included planning preventive work, and that PMA would be configured to compute the ROI for continuing to do preventive work at teval.
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The database 830 may be a component in the PMA computer 800 or be its own server. As a database, the server may comprise database management software capable of sorting, updating, retrieving, and manipulating records stored in the database. The server may comprise standard hardware found in servers such as processors, memory, network interface, storage media, etc.
The Section M&R computer may have a section maintenance and/or repair scheduler 852 configured to schedule maintenance and/or repairs on a section. The Section M&R Computer 850 may interface with a section maintenance and/or repair system. The section maintenance and/or repair system 860 may comprise various trucks 862, computers 864, supplies 866, paving equipment 868, and pavement repair technology 870 useful for paving and repairing roads. In some configurations, the PMA computer and the Section M&R computer can be a single computer.
An inspection system 880 may be a machine configured to inspect a condition for one or more sections. The inspection system may comprise computers 882 and cameras 884. The computer may comprise specialized software for determining pavement condition from images obtained by the cameras. An inspection system may be mounted in a plane, helicopter, truck, car, or other vehicle 886. An inspection system may contain controls 888 for local or remote operations of the inspection system by an inspector. An inspection system may be configured to generate inspection records. Inspection records may contain information recorded and/or obtained about distresses (such as degree and quantity) of a Section. PMA may be configured to store these records. PMA may be configured to display these records in the inspection ribbon. PMA may be configured to allow a user to manage, change, sort, and manage an inspection history of a Section. An inspection history is a collection of inspection records of the Section.
A Section is a portion of a branch. Branches may include pavement, roads, streets, parking lots, highways, parkways, runways. PMA, taxiways, or aprons. A section may be surfaced with asphalt, concrete, brick, aggregate, or mat. Paver may be configured to manage sections as its primary unit.
PMA, like many programs/applications, may comprise a plurality of windows. A window may comprise one or more buttons, fields, labels, toggles, select boxes, drop down boxes, radial boxes, etc. Each window in PMA may comprise underlying or associated logic, algorithm, or software routine configured to accept inputs, process inputs, generate results, stores results, display results, and/or issue instructions to other logic and/or windows and/or systems. For example, the inspection window may comprise an inspection logic. The inspection logic may be configured to store inspections records for a Section. Or in another example, the inventory window may comprise an inventory logic. The inventory logic may be configured to divide a large area of pavement into groupings.
PMA may have a main menu and a ribbon menu. These menus may be configured organized various windows. The ribbon menu may have an inventory, reports, selectors, work, debug, inspection, family modeling, conditions performance analysis, M&R family models inventory, M&R work planning, project formulation wizard, and wizards.
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The invention described herein was made by an employee of the United States Government and may be manufactured and used by the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefore.