Flooded Pavements Assessment App (Phase 2)
Contract #: 1036343
Pavements are dynamic structures and are affected by several parameters such as climate, loading conditions, or material properties. Current pavement analysis and design procedures often rely on empirical or mechanistic-empirical approaches, which renders their ability to incorporate moisture-dependency, especially during periods of excess moisture (such as, post flooding) and to conduct real-time and forecasted pavement capacity and load restriction analyses. While excess moisture in base and subgrade soils during and after inundation of roads has detrimental impacts on longevity and serviceability of pavements, immediate need for transportation agencies is often focused on road closure and opening decisions. The presence of excess water can be due to seasonal ground water level fluctuations, post-storm flooding, and thawing of soil frost and surface snow. An ideal agency decision App for roadway closures and/or load posting is the one that is mechanistic, and holistically evaluates different physical and environmental stressors. Such Application can enhance the resilience of pavement systems in response to extreme events and also results in more sustainable, efficient, and cost-effect roads.
In an effort supported by the NRRA – Phase I, the research team at the University of New Hampshire (UNH) has studied the mechanistic response of flexible pavement systems during and after flooding events. This involved using system dynamics modeling approach to consider the interdependency of several influential factors on pavement response through sensitivity analysis and parameterization. Further, the team at UNH has developed an initial version of a user-friendly toolkit that would help agencies to decide on post-flooding roadway opening decisions by mechanistically assessing the pavement capacity on basis of pavement section characteristics, material properties, climatic conditions (past and forecasted), and traffic scenarios. The toolkit will assist public agencies to make reliable road opening decisions during and after flooding and for various traffic classes. The first version of the UNH’s Flooded Pavement Assessment App was presented to NRRA members and also to at-large
Task 1: NRRA State Member Survey - Agency Specific Inputs for App
State feedback on the PaveSafe app both in terms of functionality and performance are critical to the success of the project. A detailed user survey will be launched where application users’ feedback, agency specific typical input for assessment of flooded pavements (e.g., traffic loading and configuration, material inputs, etc.), and recommendation for modifications and/or additions will be collected and summarized.
- Deliverable: A survey summary and synthesis will be generated and reported to TAP, which will form the basis of Task 2.
- Date due: 4/30/2022
Task 2: Development of Verification and Validation Plans
Based on the information gathered in the phase-I of this research as well as through agency specific inputs from Task-1, a detailed plan will be developed in this task for conducting verification and validation of the PaveSafe app. The verification efforts will focus on ensuring that app has accurate analysis and calculation steps to reflect pavement responses that are of same quality as those obtained with current state of the art pavement mechanical analysis systems. Validation efforts will be focused on comparing PaveSafe predictions to actual physically measured pavement responses and performances. A three pronged approach for verification and validation will be developed, these will include: (1) small and large scale laboratory physical model testing (task-3), (2) advanced numerical simulation models (task-4), (3) field data from instrumented pavement sections (task-5). The plans developed in this task will detail experimental methodologies, ranges of tested material types, initial and boundary conditions of small and large scale physical models (including moisture states) and numerical simulation details that include constitutive model types, loading types, analysis methods and associated initial and boundary conditions. The experimental plans for scaled physical testing will be developed using fractional factorial experimental design using techniques such as, Plackett-Barman method. Comparative basis used for validation purposes, especially for data from instrumented pavement sections will be defined and discussed in the plans developed during this task.
- Deliverable: A task memo describing verification and validation plans for implementations in tasks 3, 4 and 5 will serve as primary deliverable for this task. Research team will also present the verification and validation plans to the project TAP during this task.
- Date due: 6/31/2022
Task 3: Small-scale and Large-scale Physical Modeling
In this task, the testing plan for small and large scaled physical modelling that is developed in Task-2 will be executed. Small scale modelling effort will use bench-scale models (element level testing) primarily composed of geomaterials to verify and enhance PaveSafe app in terms of large number of materials with controlled moisture states and load magnitudes. Main objective of small-scale element level physical models will be to enhance mechanistic response of materials within PaveSafe. Up to twelve different small-scale models will be constructed and tested. Data generated from small-scale testing will also provide improvements to the default material inputs and model parameters used in PaveSafe. In addition to deformations, pore water pressure generation will be measured and effective stress-based limits for soil load bearing capacities will be explored. Large scale models will be constructed with multiple layers and will use various moisture saturation profiles. Main objective of large-scale models will be to provide verification datasets for PaveSafe in a multilayered system with non-uniform moisture distributions. Up to four different large-scale models will be constructed, each will be tested with up to three different moisture saturation profiles. Dynamic loading will be utilized, both surface deflection and pore water pressure in soil will determined. Measured quantities will be used to verify and enhance PaveSafe predictions.
- Deliverable: A task report will be prepared that will present the details on laboratory experimentation, results of testing and discussion of results. Improvements and modifications to PaveSafe app will be documented and discussed. Research team will present the task efforts and results to the project TAP during this task.
- Date due: 3/31/2023
Task 4: Advanced Numerical Modeling
This task will undertake advanced numerical modeling effort to expand the verification and enhancement efforts for PaveSafe beyond those conducted using small and large scale physical models. Analysis plans developed in task 2 will be executed in this task. The analysis effort is expected to utilize computational systems such as GeoStudio software package (the most recent version) where soil moisture movement and pavement mechanical response can be coupled. Models will be first evaluated using lab measured data from task 3 to ensure their veracity, thereafter pavement systems will be evaluated, and results will be used to validate and enhance PaveSafe app. The team will coordinate with TAP to select pavement systems / MnROAD cells with available moisture sensors to simulate transient seepage and pavement response.
- Deliverable: A task memo will be prepared to document advanced modelling results and comparisons between model predictions and PaveSafe. Improvements and modifications to PaveSafe app based on advanced modelling results will be documented and discussed. Modeling and output files will be also provided in the deliverable report. Research team will present the task efforts and results to the project TAP during this task.
- Date due: 7/31/2023
Task 5: Validation of App with Instrumented Road Sections
In this task research team will conduct validation and if necessary, calibration of PaveSafe app using weather and instrumentation data from selected MnROAD cells and other NRRA agency road sections. MnROAD cells from 2022 construction as well as those with useful data from previous construction cycles will be used as primary data sources. Research team will work with MnROAD staff in providing feedback with respect to instrumentation and data requirements to support this task. Research team will use a survey of NRRA agency members to gather information with respect to acquisition of field data from roadways that have been subjected to excessive moisture states. Validation efforts will employ statistical testing to demonstrate accuracy of PaveSafe app in prediction of pavement responses and to ensure that reliable load restriction and closure recommendations are predicted. This task will require considerable support from MnROAD staff. Details on support and effort of MnROAD staff is provided in section 13 (Agency Assistance) of this work-plan.
- Deliverable: A task report will be prepared to that provide details of the full-scale pavement section results, comparisons between full scale pavement response and those predicted by PaveSafe and discussions on validation and calibration of PaveSafe. Research team will present the task efforts and results to the project TAP during this task.
- Date due: 12/31/2024
Task 6: Miscellaneous Improvements to App
This task will focus on making various improvements to the PaveSafe application in terms of its usability and efficiency. Specifically, the graphical user interface (GUI) will be improved to enable user to define vehicle types (tire and axle configuration and loads), print detailed outputs and have general user experience enhancements (such as, remembering user password, saving input files etc.). This task will also undertake efforts to improve computational efficiency of the software to lower the required analysis times and adopt faster analysis programs (such as, layered elastic analysis programs).
- Deliverable: A task memo will be prepared to that provide details of enhancements that are made to PaveSafe app. An updated version of the PaveSafe app will also be provided to project TAP for testing and providing feedback to research team. Research team will present the task efforts and results to the project TAP during this task.
- Date due: 2/28/2024
Task 7: Out-of-State Conference Travel
- Deliverable: After completing the trip, provide a brief summary to the TL and PC to initiate payment for the Out-of-State Conference Travel task.
- Date due: 1/31/2024
Task 8: Draft final Report, Technical Advisory Panel Review, and Revisions
The PI will prepare a draft final report, following NRRA publication guidelines, to document project activities, findings and recommendations. This report will be reviewed by the Technical Advisory Panel (TAP), updated by the PI to incorporate technical comments, and then approved by the Technical Liaison before this task is considered complete. If possible, a TAP meeting will be scheduled to facilitate the discussion of the draft report.
- Deliverable: draft final report for TAP review, and a revised report that is technically complete and approved by the TL for publication.
- Date due: 6/31/2024
Task 9: Editorial Review and Publication of Final Report
During this task, the PI will work directly with NRRA’s contract editors to address editorial comments and finalize the document in a timely manner. The contract editors will publish the report and ensure it meets publication standards.
- Deliverable: Final Publishable Report that meets NRRA’s editorial guidelines and standards as well as final version of the PaveSafe app.
- Date due: 8/31/2024
Principal Investigator: Majid Ghayoomi, University of New Hampshire, email@example.com
Co-Principal Investigators: Eshan Dave, University of New Hampshire, firstname.lastname@example.org
Technical Liaison: Tim Andersen, MnDOT, email@example.com
Technical Advisory Panel (TAP) - email the TAP
Contact us to join this TAP
- Tim Anderson, MnDOT
- Terry Beaudry, MnDOT
- James Bittmann, MnDOT
- Amir Golalipour, FHWA
- Deepak Maskey, Caltrans
- Heather Shoup, Illinois DOT
- Raul Velasquez, MnDOT
- Ben Worel, MnDOT