Bio: Kevin Gaspard is an academic researcher from Louisiana State University. The author has contributed to research in topics: Falling weight deflectometer & Pavement management. The author has an hindex of 14, co-authored 48 publications receiving 521 citations.
TL;DR: In this article, the falling weight deflectometer (FWD) tests were performed every 161 m (0.1 mi ) over each selected roadway, along with other field tests.
Abstract: In September of 2005, Hurricane Katrina devastated New Orleans and caused sustained flooding. Limited pre- and postflooding tests indicated that the pavement structures tested were adversely impacted by the flood water. Consequently, the Louisiana Dept. of Transportation and Development hired an independent contractor to structurally test approximately 383 km ( 238 mi ) of the region’s federally aided urban highway system both inside and outside of the flooding area. Falling weight deflectometer (FWD) tests were performed every 161 m ( 0.1 mi ) over each selected roadway, along with other field tests. The FWD data were imported into a geographical information system and plotted against a USGS geo-referenced map. Comparative analyses were made possible through the use of extensive flood maps made available through NOAA and FEMA. This arrangement made it possible to classify spatially and graphically all test points on the basis of flooding versus nonflooding, short flooding duration versus longer flooding ...
TL;DR: A detailed field evaluation of the RWD system in Louisiana, in which 16 sites representing a wide array of pavement conditions were tested, was presented in this article to assess the repeatability of RWD measurements, the effect of truck speeds and the relationship between RWD and (FWD) deflection measurements and pavement conditions.
Abstract: The Rolling Wheel Deflectometer (RWD) offers the benefit to measure pavement deflection without causing any traffic interruption or compromising safety along the tested road segments. This paper presents a detailed field evaluation of the RWD system in Louisiana, in which 16 sites representing a wide array of pavement conditions were tested. Measurements were used to assess the repeatability of RWD measurements, the effect of truck speeds, and the relationship between RWD and (FWD) deflection measurements and pavement conditions. On the basis of the results of the experimental program, it was determined that the repeatability of RWD measurements was acceptable, with an average coefficient of variation at all test speeds of 15%. In addition, the influence of the testing speed on the measured deflections was minimal. The scattering and uniformity of the FWD and RWD data appear to follow closely the conditions of the roadway. Both test methods appear to properly reflect pavement conditions and structural integrity of the road network by providing for a greater average deflection and scattering for sites in poor conditions. The RWD deflection measurements were in general agreement with the FWD deflections measurements; however, the mean center deflections from RWD and FWD were statistically different for 15 of the 16 sites. DOI: 10.1061/(ASCE)TE.1943-5436.0000349. © 2012 American Society of Civil Engineers. CE Database subject headings: Pavements; Structural analysis; Deflection; Tests; Traffic safety; Louisiana. Author keywords: Pavement structural evaluation; Falling Weight Deflectometer; Rolling Wheel Deflectometer; Deflection profiles; Pavement management system.
TL;DR: In this article, the Structural Health Index (SHI) is proposed to evaluate the structural integrity of the pavement structure based on the backcalculated layer moduli of in-service pavements as predicted from FWD testing.
Abstract: Non-structural parameters such as surface distresses and ride quality have commonly been used as functional indicators in the treatment selection process. However, transportation agencies have considered in recent years implementing structural capacity indicators into their pavement management system (PMS) and decision-making processes. The objective of this study was to develop a structural condition index for Louisiana, known as the Structural Health Index (SHI), on a scale from 0 to 100 that describes the structural integrity of the pavement structure based on the backcalculated layer moduli of in-service pavements as predicted from FWD testing. Based on the developed methodology, the SHI is estimated by first backcalculating the layer moduli using a backcalculation software. Then, a sigmodal function is used to calculate the SHI. Evaluation and validation of the SHI was successful and demonstrated that the new index responded realistically to sections in poor and in good structural conditions....
TL;DR: In this paper, international roughness index (IRI) models for overlay treatment of composite and flexible pavements were developed and various factors affecting the IRI of overlay treatment were identified.
Abstract: Timely rehabilitation and preservation of pavement systems are imperative to minimising agency's costs and maximising benefits. Reasonable estimates of treatment life and pavement life extension can be made possible by developing reliable treatment performance models. Louisiana Department of Transportation and Development initiated a three-phased study to develop pavement treatment performance models in support of cost-effective selection of pavement treatment type and the time of treatment. As a result of the study, international roughness index (IRI) models for overlay treatment of composite and flexible pavements were developed. Various factors affecting the IRI of overlay treatment were identified. Climatic indices pertaining to Louisiana were developed which exhibited strong statistical significance along with the other variables as used in the IRI models. The developed IRI models provided good agreement between the measured and predicted IRI values with the majority of data within 5% of prediction e...
TL;DR: In this paper, the authors developed two statistical models to predict the resilient modulus of subgrade cohesive soils from the dynamic cone penetration (DCP) test parameters and soil properties.
Abstract: Current pavement design procedures recommend the resilient modulus of subgrade materials for pavement design and analysis. The objective of this paper is to develop two statistical models to predict the resilient modulus of subgrade cohesive soils from the dynamic cone penetration (DCP) test parameters and soil properties. The first model correlates resilient modulus to the dynamic cone penetration test parameters, while the second model correlates resilient modulus to both the dynamic cone penetration test parameters and soil properties. Field and laboratory experiments were conducted at 31 sites in Louisiana that contain four common soil types (A-4, A-6, A-7-5, and A-7-6). Field tests included DCP tests and soil sampling, while laboratory tests included determining basic soil properties and resilient modulus. Statistical analyses were conducted on the collected data, and two statistical models were developed for the prediction of resilient modulus of cohesive subgrade soils from the DCP test parameters and soil properties. The models predicted a separate data set that was not used in their development, indicating the success of the application of the dynamic cone penetration test in evaluating the resilient modulus of pavement subgrade soils. The predicted values obtained from the proposed models corresponded well with the measured resilient modulus values from the repeated load triaxial test.
31 Oct 2001
TL;DR: The American Society for Testing and Materials (ASTM) as mentioned in this paper is an independent organization devoted to the development of standards for testing and materials, and is a member of IEEE 802.11.
Abstract: The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.
01 Mar 2008
TL;DR: In this article, a regional assessment of climate change and its potential impacts on transportation systems is presented, focusing on the U.S. central Gulf Coast between Galveston, Texas and Mobile, Alabama.
Abstract: This document, part of the Synthesis and Assessment Products described in the U.S. Climate Change Science Program (CCSP) Strategic Plan. Climate affects the design, construction, safety, operations, and maintenance of transportation infrastructure and systems. The prospect of a changing climate raises critical questions regarding how alterations in temperature, precipitation, storm events, and other aspects of the climate could affect the nation's roads, airports, rail, transit systems, pipelines, ports, and waterways. Phase I of this regional assessment of climate change and its potential impacts on transportation systems addresses these questions for the region of the U.S. central Gulf Coast between Galveston, Texas and Mobile, Alabama. This region contains multimodal transportation infrastructure that is critical to regional and national transportation services. The significance of various climate factors for transportation systems was assessed.
TL;DR: In this article, the authors provide a comprehensive reference for geotechnical engineers and remote sensing experts alike by providing a comprehensive literature review and survey of current techniques and research methods.
Abstract: Evaluating the condition of transportation infrastructure is an expensive, labor intensive, and time consuming process. Many traditional road evaluation methods utilize measurements taken in situ along with visual examinations and interpretations. The measurement of damage and deterioration is often qualitative and limited to point observations. Remote sensing techniques offer nondestructive methods for road condition assessment with large spatial coverage. These tools provide an opportunity for frequent, comprehensive, and quantitative surveys of transportation infrastructure. The goal of this paper is to provide a bridge between traditional procedures for road evaluation and remote sensing methodologies by creating a comprehensive reference for geotechnical engineers and remote sensing experts alike. A comprehensive literature review and survey of current techniques and research methods is provided to facilitate this bridge. A special emphasis is given to the challenges associated with transportation assessment in the aftermath of major disasters. The use of remote sensing techniques offers new potential for pavement managers to assess large areas, often in little time. Although remote sensing techniques can never entirely replace traditional geotechnical methods, they do provide an opportunity to reduce the number or size of areas requiring site visits or manual methods.
TL;DR: In this study, the long-term pavement performance (LTPP) data and machine learning algorithms were used to study the deterioration of roads over a long period of time and show trends in pavement performance.
Abstract: Understanding the deterioration of roads is an important part of road asset management. In this study, the long-term pavement performance (LTPP) data and machine learning algorithms were us...
TL;DR: In this paper, the authors focused on the laboratory durability and mechanistic evaluation of soil-cement mixtures reinforced with Processed Cellulose fibers (PCFs) and polypropylene fibers (PFs).
Abstract: Over the years, field experiments and research information have been collected and studied on the behavior of soil–cement mixtures, and quite a few studies have been conducted for fiber reinforcement in soil–cement mixtures. This research study focuses on the laboratory durability and mechanistic evaluation of soil–cement mixtures reinforced with Processed Cellulose fibers (PCFs) and polypropylene fibers (PFs). Four soil types from various project sites in the state of Louisiana were acquired. Laboratory tests including the durability, unconfined compressive strength (UCS), indirect tensile strength (ITS), and indirect tensile cyclic load tests (ITCTs) were conducted. The results indicated that the mechanistic characteristics of the soil–cement–fiber mixtures were functions of fiber dosage, soil type and curing time. In general, the durability, UCS, ITS and fracture toughness, and resilient modulus values of soil–cement–fiber mixtures either remained the same or were greater than soil–cement mixtures. Mor...