RigidPavementDesignDeficiencies刚性路面设计缺陷.pptx

Rigid Pavement Design DeficienciesMajor shortcomings of JPCP designs based on 1972-1986 versions of the AASHTO Guide:inadequate joint load transfer,long joint spacing,erosion of base/subbase,poor subdrainageetc.Deterioration occurs earlyRehabilitation neededDevelopment of Supplemental AASHTO Design Procedure for JPCP Serious deficiencies noted in 1986 AASHTO procedureStudies showed major flaws in base/subgrade support proceduresNo easy fixesImproved structural(3D finite element)model for JPCP was developed to correct deficienciesDevelopment,Validation,Adoption:1998 Supplemental Rigid Pavement Design ProcedureDeveloped under NCHRP Project 1-30(University of Illinois at Urbana-Champaign)Validated under FHWA/LTPP research study (ERES Consultants/ARA)Adopted by AASHTO as Supplementary Rigid Pavement Design Procedure(1998)FHWA/LTPP-Supplementary Rigid Pavement Design Spreadsheet(ERES Consultants/ARA)Only JPCP For NowJointed plain Jointed plain concrete pavementconcrete pavement(JPCP)(JPCP)Most constructed rigid Most constructed rigidpavementpavement Basic design procedure Basic design procedure developeddeveloped Procedure field verified Procedure field verifiedJointed reinforcedJointed reinforcedconcrete pavementconcrete pavement(JRCP)(JRCP)Continuously reinforcedContinuously reinforcedconcrete pavementconcrete pavement(CRCP)(CRCP)Limited field verification Limited field verification1998 AASHTO JPCP Design Is BetterImproved structural modelingImproved subgrade characterizationBase course as structural layerTransverse joint spacingClimate at site is considered directlyShoulder type and slab widthJoint faulting and cracking checksUse of LTPP Data to Verify1998 AASHTO DesignDesign procedure verified using field data from LTPPInputs to 1998 AASHTO design model obtainedActual traffic log ESALs compared to predicted log W(ESALs)No significant bias found in predicting serviceability of pavements in four climatic zonesPRESENTATION OBJECTIVESWhat is the Rigid Pavement Design(RPD)Software?Development of RPD SoftwareRPD Software Features and Capabilities How To Use The RPD Software Who Should Use the RPD Software and WhyHow to Get the RPD SoftwareRigid Pavement Design Spreadsheet:FeaturesInformation sheet containing spreadsheet“User Guide”Rigid Pavement Design Spreadsheet:FeaturesCommand buttons for easy navigation between sheetsRigid Pavement Design Spreadsheet:FeaturesCommand button links to reference tablesJoint spacing and edge support conditions are direct inputsRigid Pavement Design Spreadsheet:FeaturesClimatic properties are direct inputs in the supplemental rigid pavement designRigid Pavement Design Spreadsheet:FeaturesTrue subgrade k-value is used(not adjusted for top-of-base)Rigid Pavement Design Spreadsheet:FeaturesEasy links to sensitivity analysis for various design inputsRigid Pavement Design Spreadsheet:FeaturesProject data can be saved in rows and exported to the main sheetsRigid Pavement Design Spreadsheet:FeaturesSensitivity Analysis plot displays inputs held constantRigid Pavement Design Spreadsheet:FeaturesResults sheet can be viewed on screen or can be printedRigid Pavement Design Spreadsheet:FeaturesCalculation sheet shows all calculations and displays design traffic for different slab thicknessesRigid Pavement Design Spreadsheet:FeaturesFaulting Check sheet used to estimate faulting over design life for doweled and nondoweled pavements PRESENTATION OBJECTIVESWhat is the Rigid Pavement Design(RPD)Software?Development of the RPD SoftwareRPD Software Features and Capabilities How To Use The RPD Software Who Should Use the RPD Software and WhyHow to Get the RPD SoftwareSystems RequirementsIBM PC running:Microsoft Office 95 or 97 or Microsoft Excel 7.0Using The RPD SoftwareCopy the Rigid Pavement Design(RPD)Software spreadsheet to the hard driveThe RPD software cannot be run from the floppy driveOpen the RPD spreadsheet using Microsoft ExcelUsing The RPD SoftwareClick on Enable Macros to allow execution of spreadsheet macrosUsing The RPD SoftwareClick on Input Form to access the main sheetUsing The RPD SoftwareEnter General Information for the project as shown below:Using The RPD SoftwareScroll down to enter Serviceability and PCC PropertiesUsing The RPD SoftwareEnter Base Properties,Reliability,and Standard DeviationClick on Table 14 for friction factors for different base types Using The RPD SoftwareClick on Input Form to navigate back to the main screenUsing The RPD SoftwareSelect Pavement Type and Edge Support ConditionEnter Joint SpacingUsing The RPD SoftwareEnter Climatic Properties for the design region.Click on Table 15 for climatic properties for major metropolitan areas in each State.For the first run enter the approximate subgrade k-valueUsing The RPD SoftwareClick on Calculate Traffic for traffic calculation worksheet Using The RPD SoftwareAfter entering traffic design inputs click CalculateClick Export to Input FormUsing The RPD SoftwareClick on Calculate on the main sheet to calculate thickness for design inputsClick on Calculate Seasonal k-Value for calculating seasonally adjusted k-valueUsing The RPD SoftwareEnter number of months and subgrade k-value for each season.Click Calculate.Using The RPD SoftwareUse the chart to estimate adjusted k-value for fill layer above the subgrade and/or rigid layer beneath the subgradeUsing The RPD SoftwareClick on Calculate on the main sheet to recalculate thickness for design inputs with the adjusted k-valueUsing The RPD SoftwareEnter thickness for sensitivity analysisClick Slab Thickness Sensitivity for sensitivity analysis of design traffic to slab thicknessClick on radial buttons for sensitivity analysis of design traffic to different design inputsUsing The RPD SoftwareUsing The RPD SoftwareUsing The RPD SoftwareClick on Faulting Check to perform checks for doweled and nondoweled faultingUsing The RPD SoftwareEnter dowel diameter and other design inputs for doweled pavementsUsing The RPD SoftwareClick on FI Table or Drainage CoeffTable for tables containing information regarding these inputsClick Calculate to obtain estimated faulting at end of design lifeClick Results to view and print resultsUsing The RPD SoftwareEnter design inputs for nondoweled faulting check and click CalculateClick Corner Break Check to perform top-down cracking analysisUsing The RPD SoftwareThe critical values for joint faulting can be changed by entering the appropriate values belowUsing The RPD SoftwareOn the Corner Break Check worksheet enter the built-in temperature gradient related to construction curling and moisture gradientUsing The RPD SoftwareUse one of six charts provided to estimate tensile stress at top of slab from total effective negative temperature differentialUsing The RPD SoftwareThe tensile stress at the top of the slab is less than the bottom up tensile stress for which the pavement is designedUsing The RPD SoftwareResults sheet can be viewed on screen or can be printedClick Save Data to save the design information enteredUsing The RPD SoftwareEnter ID for saving data and click OKUsing The RPD SoftwareAll design information is saved in rows with the first column corresponding to the data set ID Select appropriate row and click Export to export design information from this sheet to main sheet.This sheet can be accessed by clicking on Retrieve Data on the main sheet.PRESENTATION OBJECTIVESWhat is the Rigid Pavement Design(RPD)Software?Development of the RPD SoftwareRPD Software Features and Capabilities How To Use The RPD Software Who Should Use the RPD Software&WhyHow to Get the RPD SoftwareUsers of the RPD SoftwareState and Provincial Highway EngineersConsulting EngineersBenefits of Rigid Pavement Design SoftwareProvides key answers not previously addressed:How do I adequately characterize the subgrade support?What is the best base type for the conditions?What is the optimum joint spacing?Will this pavement fault or have corner breaks?PRESENTATION OBJECTIVESWhat is the Rigid Pavement Design(RPD)Software?Development of the RPD SoftwareRPD Software Features and Capabilities How To Use The RPD Software Who Should Use the RPD Software&WhyHow to Get the RPD SoftwareGet&Use The Software Order software:-Through LTPP homepagewww.tfhrc.gov -Through LTPP customer serviceCall 865-481-2967