详情

Impact of Curling and Warping on Concrete Pavement Phase 2

项目名称：	Impact of Curling and Warping on Concrete Pavement Phase 2
摘要：	The impacts of curling and warping on long-term pavement performance are not well understood. While some recent studies have pointed to a strong connection between the two, others have stated that these findings may not be as significant as first thought. At the same time, we continue to seek out more cost-effective ways of designing and constructing pavements without sacrificing performance. In order to do this, the curling and warping relationship must be better understood. Numerous studies have reported premature transverse cracking resulting from slab curling and warping in concrete pavements, like the series of cracks observed in an I-80 section near Adair County, Iowa. This is not only a safety issue, but it also costs transportation agencies time and money to implement repair solutions. It is therefore of paramount importance to measure the actual magnitude of curling and warping taking place in concrete pavements in order to develop performance measures and critical threshold magnitudes and gain a better understanding of their relationship to diurnal and seasonal temperature/moisture changes and long-term pavement performance. A Federal Highway Administration (FHWA) sponsored study led by the principal investigator (Dr. Halil Ceylan) at Iowa State University (ISU) focused on assessing the impact to concrete pavement smoothness from curling, warping, and other early-age behavior, in two phases (Ceylan et al. 2005, Ceylan et al. 2007a): Phase I: www.intrans.iastate.edu/research/projects/detail/?projectID=-2071199972 Phase II: www.intrans.iastate.edu/research/projects/detail/?projectID=-732230818 In the recently completed Iowa Highway Research Board (IHRB) Project TR-668: Phase I by Dr. Ceylan and his research team, �Impact of Curling and Warping on Concrete Pavement� (Phase I), field investigations were performed at six identified sites in Iowa highways to better understand the curling and warping behavior of portland cement concrete (PCC) pavements in Iowa and provide recommendations to mitigate PCC curling and warping. A stationary light detection and ranging (LiDAR) device was used to scan the slab surfaces. The degree of curling and warping along longitudinal, transverse, and diagonal directions were calculated for the predetermined slabs based on the point clouds acquired using LiDAR. The results and findings were correlated to pavement performance, mix design, pavement design, and construction-related variations at each site. Recommendations to minimize curling and warping were provided based on a literature review and field studies. Some examples of using the LiDAR point cloud data to build three-dimensional (3D) models for overall curvature of the slab shape were presented to show the feasibility of using the 3D analysis method for curling and warping. However, the PCC pavements investigated in IHRB Project TR-668: Phase I were mainly selected from Iowa highways whose pavement design features were different from those of Iowa county and city roads (e.g., thinner PCC slabs). It is important to note that thicker and shorter PCC slabs can result in a relatively lesser degree of curling and warping compared to the thinner and longer slabs. In addition, the number of PCC pavements selected and relevant data collected were not sufficient for validating the recommendations derived from the literature review findings. For example, the curling and warping literature suggested that water absorption of coarse aggregate is one of the significant mix design variables affecting warping degree/magnitude, but little reported information currently exists on water absorption of coarse aggregate used in Iowa PCC pavements to validate this literature review finding. Thus, a more comprehensive follow-up study on the impact of curling and warping on Iowa concrete pavement is recommended.
状态：	Active
资金：	370000
资助组织：	Iowa Highway Research Board
管理组织：	Iowa State University, Ames
项目负责人：	Goetz, Vanessa
执行机构：	Iowa State University, Ames
主要研究人员：	Ceylan, Halil
开始时间：	20180515
预计完成日期：	20210530
实际结束时间：	0