Download or read book Analysis of built in Curling and Warping in PCC Pavements written by Sarah K. Schmidt and published by . This book was released on 2001 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Curling and Warping on Concrete Pavement written by Halil Ceylan and published by . This book was released on 2016 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Portland cement concrete (PCC) pavement undergoes repeated environmental load-related deflection resulting from temperature and moisture variations across the pavement depth. This phenomenon, referred to as PCC pavement curling and warping, has been known and studied since the mid-1920s. Slab curvature can be further magnified under repeated traffic loads and may ultimately lead to fatigue failures, including top-down and bottom-up transverse, longitudinal, and corner cracking. It is therefore important to measure the “true” degree of curling and warping in PCC pavements, not only for quality control (QC) and quality assurance (QA) purposes, but also to achieve a better understanding of its relationship to long-term pavement performance. In order to better understand the curling and warping behavior of PCC pavements in Iowa and provide recommendations to mitigate curling and warping deflections, field investigations were performed at six existing sites during the late fall of 2015. These sites included PCC pavements with various ages, slab shapes, mix design aspects, and environmental conditions during construction. A stationary light detection and ranging (LiDAR) device was used to scan the slab surfaces. The degree of curling and warping along the longitudinal, transverse, and diagonal directions was calculated for the selected slabs based on the point clouds acquired using LiDAR. The results and findings are correlated to variations in pavement performance, mix design, pavement design, and construction details at each site. Recommendations regarding how to minimize curling and warping are provided based on a literature review and this field study. Some examples of using point cloud data to build three-dimensional (3D) models of the overall curvature of the slab shape are presented to show the feasibility of using this 3D analysis method for curling and warping analysis.
Download or read book PCC Pavement Acceptance Criteria for New Construction when Built in Curling Exists written by University of Michigan. Department of Civil and Environmental Engineering and published by . This book was released on 2008 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study's major objectives are two-fold: 1. Determine, from field and laboratory measurements, the magnitude of built-in curl/warp from a temperature gradient and moisture shrinkage gradient for Michigan conditions; and the resulting effect on JPCP resistance to mid-slab, top-down fatigue cracking. 2. Establish, based on these results and Finite Element analysis, critical values for built-in curl/warp to develop additional MDOT QC/QA acceptance criteria.
Download or read book Development and Evaluation of a Portable Device for Measuring Curling and Warping in Concrete Pavements written by Halil Ceylan and published by . This book was released on 2015 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Portland cement concrete (PCC) pavement undergoes repeated environmental load-related deflection resulting from temperature and moisture variations across pavement depth. This has been recognized as resulting in PCC pavement curling and warping since the mid-1920s. Slab curvature can be further magnified under repeated traffic loads and may ultimately lead to fatigue failures, including top-down and bottom-up transverse, longitudinal, and corner cracking. It is therefore significant to measure the "true" degree of curling and warping in PCC pavements, not only for quality control (QC) and quality assurance (QA) purposes, but also for better understanding of its relationship to long-term pavement performance. Although several approaches and devices—including linear variable differential transducers (LVDTs), digital indicators, and some profilers—have been proposed for measuring curling and warping, their application in the field is subject to cost, inconvenience, and complexity of operation. This research therefore explores developing an economical and simple device for measuring curling and warping in concrete pavements with accuracy comparable to or better than existing methodologies. Technical requirements were identified to establish assessment criteria for development, and field tests were conducted to modify the device to further enhancement. The finalized device is about 12 inches in height and 18 pounds in weight, and its manufacturing cost is just $320. Detailed development procedures and evaluation results for the new curling and warping measuring device are presented and discussed, with a focus on achieving reliable curling and warping measurements in a cost effective manner.
Download or read book Curling and Warping of Concrete Pavement written by Nicole Carter and published by . This book was released on 2016 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project focuses on characterization of pavement behavior as it undergoes short-term curling and warping. Curling and warping cause slab deflections due to a temperature gradient and moisture gradient, respectively; this can result in excessive cracking and reduce the quality and lifetime of the pavement. In this study, one test section consisting of three panels was analyzed for early-age curling, warping, and shrinkage behavior. Deflection readings were taken on all three panels of the test section and one panel was instrumented with strain gages and moisture sensors. This procedure was a successful proof of concept in which we were able to determine that a relationship exists between strain, moisture, and deflection, indicating a relationship with curling and warping. Although data collected corresponds with the expected behavior, the amount of error produced from the test equipment and operators makes it difficult to accurately calculate deflection due to curling versus that due to warping.
Download or read book Sensitivity Analysis of Rigid Pavement Design Inputs Using Mechanistic empirical Pavement Design Guide written by Alper Guclu and published by . This book was released on 2005 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement design procedures, available in the literature, do not fully take advantage of mechanistic concepts, which make them heavily rely on empirical approaches. Because of the heavy dependence on empirical procedures, the existing design methodologies do not capture the actual behavior of Portland cement concrete (PCC) pavements. However, reliance on empirical solutions can be reduced by introducing mechanistic-empirical methods, which is now adopted in the newly released mechanistic-empirical pavement design guide (MEPDG). This new design procedure incorporates a wide range of input parameters associated with the mechanics of rigid pavements. To compare the sensitivity of these various input parameters on the performance of concrete pavements, two jointed plain concrete pavement (JPCP) sites were selected in Iowa. These two sections are also part of the Long Term Pavement Performance (LTPP) program where a long history of pavement performance data exists. Data obtained from the Iowa Department of Transportation (Iowa DOT) Pavement Management Information System (PMIS) and LTPP database were used to form two standard pavement sections for the comprehensive sensitivity analyses. The sensitivity analyses were conducted using the MEPDG software to study the effects of design input parameters on pavement performance of faulting, transverse cracking, and smoothness. Based on the sensitivity results, ranking of the rigid pavement input parameters were established and categorized from most sensitive to insensitive to help pavement design engineers to identify the level of importance of each input parameter. The curl/warp effective temperature difference (built-in curling and warping of the slabs) and PCC thermal properties are found to be the most sensitive input parameters. Based on the comprehensive sensitivity analyses, the idea of developing an expert system was introduced to help the pavement design engineers identify the input parameters that they can modify to satisfy the predetermined pavement performance criteria. Predicted pavement distresses using the MEPDG software for the two Iowa rigid pavement sites were compared against the measured pavement distresses obtained from the Iowa DOT's PMIS and comparison results are discussed in this study.
Download or read book A High Speed Profiler Based Slab Curvature Index for Jointed Concrete Pavement Curling and Warping Analysis written by Christopher Ronald Byrum and published by . This book was released on 2001 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Study on the Curling and Warping of Hardened Rigid Pavement Slabs written by Yinghong Qin and published by . This book was released on 2011 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Temperature Curling and Moisture Warping on Jointed Concrete Pavement Performance written by United States. Federal Highway Administration. Office of Pavement Technology and published by . This book was released on 2010 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: This TechBrief summarizes the results of a study on curling and warping in jointed concrete pavement (JCP). Profile measurements, following quality assurance plans developed under the study, were collected in all U.S. climate zones, diurnal periods, and seasons of the year to obtain sufficient data to fully characterize slab curvatures. Both functional and structural pavement performance were measured to correlate performance to curling and warping. Products of the study include a new technique that quantifies the magnitude of JCP curling and warping and a system to assess the influence of diurnal and seasonal changes on JCP curvature and pavement unevenness.
Download or read book Field Evaluation of Built in Curling Levels in Rigid Pavements written by Rita E. Lederle and published by . This book was released on 2011 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project assesses the mechanisms and methods to assess built-in curling of jointed plain concrete pavements. Through the use of literature review or previous work, material, geometric, restraint, curing and local ambient relative humidity were found to be factors affecting both construction curl and drying shrinkage, leading to built-in curl of concrete slabs. Through the extensive use of a finite element program, an artificial neural network (ANN) was developed to backcalculate the built-in curl of an in-service concrete slab using falling-weight deflectometer testing for a variety of parameters. This ANN was used to evaluate existing concrete test cells at the MnROAD facility. In addition to non-destructive evaluations, significant studies into surface profiling of these same test cells was conducted to evaluate the most accurate and simplified method for evaluating built-in curl. While the nondestructive ANN method evaluates the interaction of the concrete slab with the underlying layers, the surface profiling method does not directly reflect this interaction, but instead gives an understand of the slab's curvature at the surface. Comparisons between these methods as well as between numerous different surface profiling methods were conducted.
Download or read book Computer based Guidelines for Concrete Pavements written by and published by . This book was released on 2005 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents enhancement incorporated in the (HIgh PERformance PAVing) HIPERPAV(trademark) II software. Enhancements made within this project include the addition of two major modules: a module to predict the performance of Jointed Plain Concrete Pavement (JPCP) as affected by early-age factors and a module to predict the early-age behavior (first 72 hours) and early life (up to 1 year) of Continuously Reinforced Concrete Pavement (CRCP). Two additional Federal Highway Administration (FHWA) studies were also incorporated: one that predicts dowel bearing stresses as a function of environmental loading during the early age and a module for optimization of concrete paving mixes as a function of 3-day strength, 28-day strength, and cost. Additional functionality to the software also was incorporated by reviewing and prioritizing the feedback provided by users of the first generation of the software, HIPERPAV 1.
Download or read book Design and Construction of PCC Pavements written by Leslie Titus-Glover and published by . This book was released on 1998 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Curling Warping and Other Early age Behavior on Concrete Pavement Smoothness written by and published by . This book was released on 2007 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the activities in Phase II of "Assessing the Impact to Concrete Pavement Smoothness from Curling, Warping, and other Early-Age Behavior: Early, Frequent, and Detailed (Project 16)." The purpose of this report is to obtain detailed information about factors affecting pavement smoothness during the critical time immediately following construction by conducting a controlled field evaluation of three concrete pavement construction projects. In Phase II, both field and laboratory testing of the materials and construction process were conducted for two newly constructed Jointed Plain Concrete Pavement (JPCP) test sections; one on highway U.S. 34 near Burlington and the other on U.S. 30 near Marshalltown, Iowa. Extensive pavement profiling was also performed during strategic times after placement. This report fulfills the remaining requirements of Phase II. As a whole, the data collection effort undertaken by the project team was a success. The result of this project is a large amount of quality data on the early-age effects of curling and warping on pavement smoothness. By using the data from this research and by using the mathematical models developed as part of current FHWA studies and elsewhere, the complex relationships between concrete pavements curling, warping, and other early-age behavior and pavement smoothness were discussed and presented. This study shows that the curling and warping behaviors at early ages are influenced not only by temperature variation but also by other environmental effects such as the moisture variation, drying shrinkage, and temperature conditions during pavement construction. Within the scope of this project, it can be concluded that measurable changes of early-age pavement smoothness do occur over time from the standpoint of smoothness specifications.
Download or read book Truck pavement economic Modeling and In situ Field Test Data Analysis Applications written by Shad M. Sargand and published by . This book was released on 2007 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: A jointed concrete pavement on I-490 near Rochester, NY, was reconstructed using three different dowel bar spacings in eastbound test sections. Two sections in the westbound direction were instrumented to monitor environmental strain, deflections, and pavement temperatures. Monitoring of the westbound sections was conducted at the time of construction, after 28 days of curing, and at various intervals over the next two years. The instrumentation included deep and shallow linear variable differential transducers (LVDTs) to measure displacements in the center and the corners of the slabs, thermocouples at four depths near the center and at one corner of the slab, and vibrating wire strain gages with built-in thermistors in the center and the left wheel path. Air temperature data were also gathered during monitoring periods. Data were taken from the instruments at the time of construction, and at 37 days (after curing), 12 months, 16 months, and 28 months after construction. In addition to instrumentation readings taken over an approximately 24-hour period, each visit included slab shape measurements made with a Dipstick®, and deflections measured with a falling weight deflectometer (FWD) on the westbound sections. The final data collection visit, in October 2004, also included FWD testing and profilometer measurements on the eastbound sections. In measuring the pavement response, the FWD and LVDT data both indicated some loss of support that varied in response to changing temperature conditions. Of the three dowel bar arrangements, the E2 arrangement that used bars with the smallest cross-section and the narrowest spacing had the best load transfer efficiency.
Download or read book Pavement Cracking written by Imad L. Al-Qadi and published by CRC Press. This book was released on 2008-07-30 with total page 932 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internationally, much attention is given to causes, prevention, and rehabilitation of cracking in concrete, flexible, and composite pavements. The Sixth RILEMInternational Conference on Cracking in Pavements (Chicago, June 16-18, 2008) provided a forum for discussion of recent developments and research results.This book is a collection of papers fr
Download or read book Characterization of Effective Built in Curling and Concrete Pavement Cracking on the Palmdale Test Sections written by Shreenath Rao and published by . This book was released on 2005 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of the Effect of Curling on As constructed Smoothness and Ride Quality of KDOT Portland Cement Concrete PCC Pavements written by Zahidul Siddique and published by . This book was released on 2004 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental effects such as temperature and/or moisture gradient across the thickness of the concrete pavement slab can cause curling, which also affects the roughness. In this report, the effect of curling on as-constructed smoothness as well as early-life roughness of Portland Cement Concrete Pavements (PCCP) was investigated. Twelve test sections on six newly built concrete pavement projects on Interstate routes 70 and 135 were selected. Periodic longitudinal profile data was collected by a South Dakota-type profiler on each wheel path of both the driving and passing lanes. A digital method was developed to separate curling from the longitudinal profile using Fast Fourier Transform (FFT). International Roughness Index (IRI) values were calculated for the original profile, curled profile, and profile without curling. The contribution of curling to the measured roughness was found to be significant.
