Increased pavement deterioration induced by flooding: A case study of 2013 Colorado floods using stochastic Monte Carlo simulations in discrete-time Markov chains (DTMC)

Els gestors de xarxes viàries pateixen dificultats a l'hora de pronosticar l'impacte de les inundacions en el deteriorament de paviments i, per tant, les operacions de manteniment, assignació pressupostària o estratègies posteriors a inundacions encara no tenen una clara integració en els sistemes de gestió de paviments. Les inundacions han impactat severament la xarxa de carreteres de EUA durant les últimes dècades, i es preveu que aquesta tendència continuï augmentant en la major part dels EUA causa de el canvi climàtic. No obstant això, s'han identificat pocs models que avaluïn l'impacte a curt termini de les inundacions, la majoria d'ells molt difícils d'implementar a nivell de xarxa i no s'ha definit una tendència clara de deteriorament posterior a les inundacions. En la present tesi, es va investigar i va discutir un enfocament metodològic integral amb base estadística que determina el deteriorament de les seccions d'asfalt inundades, per al cas d’estudi de les inundacions de Colorado de 2013. Els resultats mostren com la condició de la carretera abans de la inundació influeix en deteriorament dels paviments. Una anàlisi de risc, aplicant simulacions estocàstiques de Monte Carlo i anàlisis deterministes, permet quantificar la pèrdua de condició per a paviments inundats, utilitzant el IRI com a mesura de deteriorament.Los gestores de redes viarias sufren dificultades a la hora de pronosticar el impacto de las inundaciones en el deterioro del pavimento y, por lo tanto, las operaciones de mantenimiento, asignación presupuestaria o estrategias posteriores a inundaciones aún carecen de integración en los sistemas de gestión de pavimentos. Los eventos de inundaciones han impactado severamente la red de carreteras de EEUU durante las últimas décadas, y se prevé que esta tendencia siga aumentando en la mayor parte de EEUU debido al cambio climático. Sin embargo, se han identificado pocos modelos que evalúen el impacto a corto plazo de las inundaciones, la mayoría de ellos muy difíciles de implementar a nivel de red y no se ha definido una tendencia clara de deterioro posterior a las inundaciones. En la presente tesis, se investigó y discutió un enfoque metodológico integral con base estadística que determina el deterioro de las secciones asfálticas inundadas, para el estudio de caso de las inundaciones de Colorado de 2013. Los resultados muestran cómo la condición de la carretera antes de la inundación influye en deterioro de los pavimentos. Un análisis de riesgo, aplicando simulaciones estocásticas de Monte Carlo y análisis determinísticos, permite cuantificar la pérdida de condición para pavimentos inundados, utilizando el IRI como medida de deterioro.Road asset managers endeavor to forecast the impact of floods in pavement deterioration, and therefore establishing maintenance operations, budget allocation, or post-flood strategies have yet to be defined in Pavement Management Systems (PMS). Flood events have severely impacted the roadway US network during the last decades, and this trend is forecasted to keep rising due to climate change in most parts of the United States. However, few models assessing the short-term impact of floods were identified, most of them very difficult to implement for network analysis, and no post-flood deterioration trend defined. A comprehensive statistically-based methodology approach determining the conceptual evolution of flooded asphalt sections for the case study from the 2013 Colorado floods is researched and discussed. The results show how the pre-flood road condition influences the loss of pavement condition due to the flood. A risk-based approach, using stochastic Monte Carlo simulations and deterministic analyses, is used to quantify the expected loss of pavement condition, using the IRI as a proxy for road deterioration (RD)

Assessing the Mechanical Response of Pavements During and After Flooding

Flooding is recognized as a catastrophic event and a threat to the load carrying capacity of pavements around the world. In the aftermath of flooding, the pavement structure could be inundated and fully saturated. The significant increase of water within pavement layers may cause weakness and induce damage with traffic loading, subsequently increasing maintenance costs and shortening pavement service life. The assessment of the structural performance and capacity of flooded pavements remains complicated due to lack of structural data immediately following flooding, and information about the pavement structure and materials is not always readily available. Currently, the decision to open roads for traffic is based on the assessment of the pavements, which relies on visual inspection and experience. An incorrect assessment of the flooded pavement structural capacity due to unforeseen conditions may lead to unexpected outcomes or failure. The objective of this dissertation is to advance the current knowledge of the behavior of flooded pavements, based on their performance properties and structural capacities. Several methodologies have been developed and examined for a set of pavement structures with different material types using layered elastic analysis to (1) investigate the pavement response to traffic loads under different moisture conditions, (2) identify the important parameters that affect the performance of inundated pavements, (3) investigate the influence depth of the subsurface water level at which the road can withstand traffic with zero to minimum deterioration, (4) estimate the in-situ pavement surface deflection, and (5) identify the catastrophic failure of pavements in post-flood events. The findings showed a significant reduction in structural capacity when the pavement structure was in the fully saturated condition, but the road could regain its capacity after desaturation and recession of water level. The influence depth for the subsurface water level was found to be dependent on pavement structure and material type. The most accurate method to estimate the in-situ measured deflection is to divide the soil layer into several layers in the layered elastic analysis. Accurate layer thicknesses, traffic type, and interlayer bond condition are the important factors for evaluating changes in expected horizontal strain at the bottom of asphalt layer, used for predicting fatigue cracking pavement performance. The type of base and subgrade materials are the most important factors for evaluating the changes in expected vertical strain at the top of subgrade layer, used to predict pavement rutting performance. This dissertation provides information to agencies that will enhance their understanding of the performance and structural capacity of pavements in post-flood events

The Impact of Hurricane Harvey on Pavement Structures in the South East Texas and South West Louisiana

This study developed a methodology to estimate the damage caused by flooding, such that caused by Hurricane Harvey, on a road or street network. The flooded street or pavement sections are identified using GIS flood maps with street GIS maps used for pavement management systems (PMS) by cities or state authorities. Then the damage caused by flooding directly through the increase moisture in foundation layers or indirectly due to the increase heavy traffic during the relief effort is estimated. An example Excel macro was created to illustrate the estimation process. The methodology estimates the increase in rehabilitation costs since the flooding imposes that many rehabilitation works must be done earlier than anticipated before the flooding. The methodology also estimated the increase in fuel consumption caused by the increased in pavement roughness if the rehabilitation works are done when anticipated before the flooding. The methodology and the Excel macro can also be used to identify the pavement structures with better resilience to the flooding by grouping sections based on the flooding duration (no flooding, single and multiple day flooding) and on design features such as pavement type, functional class, age or time from the most recent resurfacing or reconstruction, subgrade soil type, traffic volume, layer thickness

Wet runways

Aircraft stopping and directional control performance on wet runways is discussed. The major elements affecting tire/ground traction developed by jet transport aircraft are identified and described in terms of atmospheric, pavement, tire, aircraft system and pilot performance factors or parameters. Research results are summarized, and means for improving or restoring tire traction/aircraft performance on wet runways are discussed

NASA Boeing 737 Aircraft Test Results from 1996 Joint Winter Runway Friction Measurement Program

A description of the joint test program objectives and scope is given together with the performance capability of the NASA Langley B-737 instrumented aircraft. The B-737 test run matrix conducted during the first 8 months of this 5-year program is discussed with a description of the different runway conditions evaluated. Some preliminary test results are discussed concerning the Electronic Recording Decelerometer (ERD) readings and a comparison of B-737 aircraft braking performance for different winter runway conditions. Detailed aircraft parameter time history records, analysis of ground vehicle friction measurements and harmonization with aircraft braking performance, assessment of induced aircraft contaminant drag, and evaluation of the effects of other factors on aircraft/ground vehicle friction performance will be documented in a NASA Technical Report which is being prepared for publication next year

Structural Assessment of Inundated Roadways in Livingston Parish, Louisiana With the Falling Weight Deflectometer

Researchers discovered strong evidence of damage to Livingston Parish\u2019s inundated roadway system during the flood of August 2016. LTRC conducted a comprehensive structural assessment of inundated roadways in Livingston Parish, Louisiana with the falling weight deflectometer (FWD). Treated (inundated) versus non-treated (non-inundated) statistical methods were employed to prove damage. Three parameters from the FWD were used in the analysis, in-place structural number (SNeff), deflection at the first sensor of the FWD (D1), and subgrade resilient modulus (Mr). The damage was translated into an equivalent thickness of asphaltic concrete (AC) pavement from the parameter of SNeff using pavement design methods typically used by the Louisiana Department of Transportation and Development (DOTD). The data were sorted into three groups based on the thickness of the AC pavement: All data points (all thickness groups), 4 in. to 3 in. group, and 2 in. to 2.5 in. group. The statistical analysis of the entire set of data indicated that statistical differences existed for all three parameters, SNeff, D1, and subgrade Mr. Regarding SNeff, the difference between the mean values of the non-inundated and inundated roadways was equivalent to approximately 1 in. of AC. The differences in the mean values for D1 and subgrade Mr indicated that the inundated pavements were approximately 22.5 percent and 10.3 percent, respectively, weaker than the non-inundated pavements. Statistical comparisons on the 4 in. to 3 in. thickness group indicated that statistical differences existed for all three parameters, SNeff, D1, and subgrade Mr as with the all thickness group. In the case, the differences in SNeff was equivalent to approximately 2.5 in. of AC. Regarding the D1 and subgrade Mr parameters, the results indicated that the inundated pavements were approximately 56.5 percent and 25.3 percent, respectively, weaker than the non-inundated pavements. Statistical differences in the three parameters, SNeff, D1, and subgrade Mr for the 2.0 in. to 2.5 in. thickness group were not discovered; however, differences in magnitudes of the means for each parameter were discovered, all indicating that the inundated pavements were weaker than the non-inundated pavements. Regarding the SNeff, the difference in the mean values between the non-inundated and inundated pavements were equivalent to approximately 0.5 in. of AC. The difference in stiffness between the inundated and non-inundated pavements based on the D1 parameter was approximately 22.6 percent, while the strength difference in subgrade Mr was approximately 4.6 percent

Hydrodynamics of tire hydroplaning Final report, 1 Jul. 1965 - 30 Jun. 1966

Hydrodynamics including lift and drag forces for aircraft pneumatic tire hydroplanin

Pavement Resilience: State of the Practice

Contract DTFH6115D00005L Task Order 693JJ318F000230For the Federal Highway Administration (FHWA), resilience, with respect to a project, means a project with the ability to anticipate, prepare for, and or adapt to changing conditions and or withstand, respond to, and or recover rapidly from disruptions. This includes the ability: (A) to resist hazards or withstand impacts from weather events and natural disasters, or to reduce the magnitude or duration of impacts of a disruptive weather event or natural disaster on a project; and (B) to have the absorptive capacity, adaptive capacity, and recoverability to decrease project vulnerability to weather events or other natural disasters. 23 U.S.C. \ua7 101(a)(24). As noted in FHWA Order 5520 (FHWA 2014), climate change and extreme weather events present significant and growing risks to the safety, reliability, effectiveness, and sustainability of the Nation\u2019s transportation infrastructure. This document examines pavement resilience, a subset of transportation resilience, and describes the state of knowledge, practice, and future needs based on (1) key national and international climate documents, (2) a FHWA approach to resilience, (3) the results of an unpublished literature review, and (4) the findings from two FHWA-sponsored Peer Exchanges on pavement resilience held in late 2020

The Effects of Extreme Weather Events on Flexible Pavement

Extreme weather events, such as excessive rainfall causing flooding and elevated maximum temperatures, are becoming a regular occurrence each year in Australia and are increasing in frequency. These weather events can possibly be contributed to climate change, which is a major issue that is likely to worsen in the years to come as we continue to burn more fossil fuels. Flexible pavements are designed with consideration to the surrounding environment and to an extent, the current climate conditions known to the area. Heat is a known factor that can severely affect the design life of flexible pavements. It can cause surface cracks that, if left untreated, can allow moisture ingress to the sub-base and/or sub-grade layers of the pavement. However, this report will primarily focus on excessive rainfall resulting in flooding as it is a more quantifiable cause of pavement deterioration. This research project aims to analyse pavement deterioration that can be attributed to by extreme weather events by comparing data collected from the City of Gold Coast (Council’s) Pavement Management System. The primary focus of this project, flooding events, looked to compare road deterioration rates between frequently flooded sections of road to less-affected sections of the same road. This methodology allowed the elimination of variables which may have contributed to pavement deterioration such as increasing AADT, pavement age, and surface age, and ensured the only considerable contribution to the pavement’s deterioration was due to exposure to flooding events. This analysis was performed on four roads in the form of case studies. Analysis of the results revealed that the road sections which experienced flooding did show evidence of greater deterioration in comparison to the non-flood prone road sections. These deteriorations appeared in the forms of cracks, rutting and stripping. However, not all case studies showed the same intensity of damage or even the same damage type. It was proven though, that in all four case studies,there was a reduction in PCI values and an increase in roughness. A cost analysis was also conducted to better understand the financial impact these weather events may have on Council’s flexible road pavements