Evaluation of inverted pavement by structural condition indicators from falling weight deflectometer

2022 ◽  
Vol 319 ◽  
pp. 125991
Author(s):  
Xi Jiang ◽  
Jay Gabrielson ◽  
Baoshan Huang ◽  
Yun Bai ◽  
Pawel Polaczyk ◽  
...  
Keyword(s):  
Structural Condition ◽  
Falling Weight Deflectometer ◽  
Condition Indicators ◽  
Falling Weight

Structural Analysis for APT Sections Based on Deflection Parameters

2019 ◽  
Vol 2673 (3) ◽  
pp. 313-322 ◽  
Author(s):  
Edgar Camacho-Garita ◽  
Robinson Puello-Bolaño ◽  
Piero Laurent-Matamoros ◽  
José P. Aguiar-Moya ◽  
Luis Loria-Salazar
Keyword(s):  
Costa Rica ◽  
Structural Condition ◽  
Pavement Management ◽  
System Level ◽  
Radius Of Curvature ◽  
Condition Indicators ◽  
Structural Capacity ◽  
Pavement Layers ◽  
Pavement Structures ◽  
Falling Weight

This paper reviews the use of pavement structural condition indicators determined through deflection measurements as a means to monitor structural capacity. The deflection measurements were performed with a road surface deflectometer and a falling weight deflectometer on the various test tracks of an accelerated pavement test (APT) facility. The indicators estimation was based on the deflection data collected from different structures, and it was observed that it is feasible to improve the backcalculation analysis and help overcome some of the limitations associated with such a procedure. For this research, Radius of Curvature, AREA, Normalized AREA, BLI (Upper layers), MLI (Middle layers), and LLI (Lower layers) were the analyzed parameters. Each parameter is related to the structural condition of particular pavement layers. Therefore, the parameters allow general characterization of the pavement layers, and make it possible to detect deteriorated layers. The pavement structures were trafficked by means of an APT at the PaveLab facility at the University of Costa Rica. The deflection parameters were calculated through the APT data, showing the possible use of these indicators at the pavement management system level in Costa Rica, helping the categorization of the pavement structures in service, mainly because the parameters require few input data, and are useful where the available structural condition information is limited. The data presented in this paper show the variation of the different condition indicators throughout the service life of the analyzed pavement structures. The data are also used to compare different structures, their characteristics, and the change in their stiffness associated with damage.

scholarly journals Experimental continuously reinforced concrete pavement parameterization using nondestructive methods

2016 ◽  
Vol 9 (2) ◽  
pp. 263-274
Author(s):  
L. S. Salles ◽  
J. T. Balbo
Keyword(s):  
Reinforced Concrete ◽  
Load Transfer ◽  
Structural Condition ◽  
Concrete Pavement ◽  
Pavement Performance ◽  
Falling Weight Deflectometer ◽  
Matching Process ◽  
Load Transfer Efficiency ◽  
Falling Weight ◽  
The University

ABSTRACT Four continuously reinforced concrete pavement (CRCP) sections were built at the University of São Paulo campus in order to analyze the pavement performance in a tropical environment. The sections short length coupled with particular project aspects made the experimental CRCP cracking be different from the traditional CRCP one. After three years of construction, a series of nondestructive testing were performed - Falling Weight Deflectometer (FWD) loadings - to verify and to parameterize the pavement structural condition based on two main properties: the elasticity modulus of concrete (E) and the modulus of subgrade reaction (k). These properties estimation was obtained through the matching process between real and EverFE simulated basins with the load at the slab center, between two consecutive cracks. The backcalculation results show that the lack of anchorage at the sections end decreases the E and k values and that the longitudinal reinforcement percentage provides additional stiffness to the pavement. Additionally, FWD loadings tangential to the cracks allowed the load transfer efficiency (LTE) estimation determination across cracks. The LTE resulted in values above 90 % for all cracks.

Assessment of Falling Weight Deflectometer Data for Stabilized Flexible Pavements

2000 ◽  
Vol 1709 (1) ◽  
pp. 19-25 ◽  
Author(s):  
Alexander K. Appea ◽  
Imad L. Al-Qadi
Keyword(s):  
Resilient Modulus ◽  
Ground Truth ◽  
Monitoring And Evaluation ◽  
Structural Condition ◽  
Base Layer ◽  
Falling Weight Deflectometer ◽  
Structural Capacity ◽  
Pavement Monitoring ◽  
Aggregate Base ◽  
Falling Weight

Backcalculation of pavement moduli through the utilization of the falling weight deflectometer (FWD) is used for pavement monitoring and evaluation. The performance and structural condition of nine flexible pavement test sections built in Bedford County, Virginia, have been monitored over the past 5 years using FWD. The nine sections include three groups with aggregate base layer thicknesses of 100, 150, and 200 mm, respectively. Sections 1, 4, and 7 are control, whereas Sections 2, 5, 8 and 3, 6, 9 are stabilized with geotextiles and geogrids, respectively. The FWD testing used five double-load drops ranging from 26.5 to 58.9 kN. The deflection basins obtained from the testing have been analyzed using the ELMOD backcalculation program to find the pavement structural capacity and to detect changes in the aggregate resilient modulus. The analysis shows a reduction in the backcalculated resilient modulus of the 100-mmthick base layer. The reduction was 33 percent over 5 years for the nonstabilized section compared with the geosynthetically stabilized section. The reduction in base layer resilient modulus may have resulted from subgrade fine migration into this layer as confirmed by excavation. The study confirms the effectiveness of using woven geotextile as a separator in a pavement system built over weak subgrade. This supports the continuous rutting measurements and ground truth excavation conducted in late 1997.

Another look at delineation of uniform pavement sections based on falling weight deflectometer deflections data

2016 ◽  
Vol 43 (1) ◽  
pp. 40-50 ◽  
Author(s):  
Syed Waqar Haider ◽  
Sudhir Varma
Keyword(s):  
Structural Condition ◽  
Mean Difference ◽  
Falling Weight Deflectometer ◽  
Pavement Surface ◽  
State Highway ◽  
Practical Standpoint ◽  
The Mean ◽  
Mean Differences ◽  
Falling Weight ◽  
Local Variability

The large amount of data commonly used to characterize the pavement surface and structural conditions offer a challenge to practitioners making decisions about the representative value of a particular parameter for design. While a large number of observations along the length of a road allow a better quantification of the expected value and variance of a parameter, basing a design on an average parameter along the project length will typically be uneconomical and less reliable. Therefore, pavement surface and structural condition data along a project length needs to be delineated into uniform sections. The design can be performed individually for each of these uniform sections to achieve economy without compromising reliability level. This paper documents delineation methods that explicitly address the problem of segmentation of measurement series obtained from Falling weight deflectometer deflections. Modifications in the existing American Association of State Highway and Transportation Officials (AASHTO) delineation procedure were incorporated to address the mean differences and the local variability. The results of delineation show that the AASHTO methodology ignores the local variations along the project length which may not be valid from a practical standpoint while designing rehabilitation or preservation strategies. The inclusion of restrictions on mean difference and section length resulted in better delineation than the AASHTO method but it could be sensitive to local variations of the deflections within a section. The delineation approach can handle the local deflection variations within a section if appropriate constraints on the local variations are imposed. The results from the delineation of field deflections showed that the restrictions on mean difference, minimum section length, and location variability are vital to delineate the project length into appropriate homogenous sections which can be different from each other from both statistical and practical viewpoints.

scholarly journals Lessons Learned on Geosynthetics Applications in Road Structures in Silesia Mining Region in Poland

2019 ◽  
Vol 9 (6) ◽  
pp. 1122 ◽  
Author(s):  
Jacek Kawalec ◽  
Marcin Grygierek ◽  
Eugeniusz Koda ◽  
Piotr Osiński
Keyword(s):  
Underground Mining ◽  
Negative Impact ◽  
Back Analysis ◽  
Structural Condition ◽  
Lessons Learned ◽  
Coal Extraction ◽  
Falling Weight Deflectometer ◽  
Materials Used ◽  
Mining Coal ◽  
Falling Weight

The paper aims at the research of pioneering applications of geosynthetic materials used for improvement of anthropogenic material for road contraction challenges in Poland. The presented case study concerns a road embankment construction process within an area of underground mining coal extraction for which significant deformations have been frequently recorded. To improve the bearing capacity of the structure base, the geosynthetic materials were used. The question; however, was how the anthropogenic materials, filling the embankment, will interact with each other over time. The assessment of the structural condition of the motorway surface was performed using the falling weight deflectometer and the calculated modules based on the back-analysis method. They confirmed the effectiveness of the geosynthetics used in the study. They also revealed that the mining exploitation, with simultaneous use of aggregate stabilization with geogrids, did not cause significant changes in the stiffness of the pavement layers. All observations, based on both field and laboratory tests, did not show any negative impact of anthropogenic soils on the structural behavior of geogrids.

Application of Traffic Speed Deflectometer for Network-Level Pavement Management

2018 ◽  
Vol 2672 (40) ◽  
pp. 348-359 ◽  
Author(s):  
Shivesh Shrestha ◽  
Samer W. Katicha ◽  
Gerardo W. Flintsch ◽  
Senthilmurugan Thyagarajan
Keyword(s):  
Surface Condition ◽  
Structural Condition ◽  
Pavement Management ◽  
Falling Weight Deflectometer ◽  
Pavement Management System ◽  
State Highway ◽  
Structural Evaluation ◽  
Traffic Speed ◽  
State Highway Agencies ◽  
Falling Weight

In this paper, the traffic speed deflectometer (TSD), a device used for network level structural evaluation, is assessed. TSD testing was performed in nine states on a total of 5,928 miles (some repeated) during three time periods: November 2013, May to July 2014, and June to September 2015. This paper presents (1) the results of repeatability and comparison of the TSD with the falling weight deflectometer (FWD), (2) the results of the comparison of TSD measurements with typical pavement management system (PMS) data, and (3) an approach that can be implemented by State Highway Agencies (SHAs) to incorporate indices derived from TSD data into their PMS decision-making process. The results show that repeated TSD measurements follow similar trends and the TSD measurements and FWD measurements on the same pavement sections follow similar trends as well. Comparing TSD measurements with PMS surface condition data confirmed that the TSD provided valuable information about the structural condition of the tested pavement sections that cannot be derived from the already available pavement surface condition as part of an agency’s PMS. An example of how TSD information can be used to refine the triggered maintenance treatment category as part of a network-level PMS analysis is presented for a roughly 75-mile section of I-81 south in Virginia.

scholarly journals Investigating In Situ Properties of Recycled Asphalt Pavement with Foamed Asphalt as Base Stabilizer

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Christina Plati ◽  
Andreas Loizos ◽  
Vasilis Papavasiliou ◽  
Antonis Kaltsounis
Keyword(s):  
Asphalt Pavement ◽  
Structural Condition ◽  
Falling Weight Deflectometer ◽  
Recycled Asphalt Pavement ◽  
Recycled Asphalt ◽  
Foamed Asphalt ◽  
Critical Issues ◽  
Ground Penetrating ◽  
Falling Weight

The objective of the present study was to conduct a comprehensive field experiment for the in situ assessment of in-depth recycled asphalt pavement using foamed asphalt as a stabilization treatment for base works. For this purpose Nondestructive Testing (NDT) data collected using the Falling Weight Deflectometer (FWD) and Ground Penetrating Radar (GPR) along a foamed asphalt recycled pavement section was thoroughly analysed. Critical issues including the stabilized material curing and the contribution of the asphalt layers to the structural properties of the in-depth recycled pavement are discussed. In addition, recommendations concerning the improvement of the structural condition of the in-depth recycled pavement are developed based on this practical approach of investigation using NDT.

Evaluation of structural responses of continuously reinforced concrete pavement (CRCP) using falling weight deflectometer

2016 ◽  
Vol 43 (1) ◽  
pp. 28-39 ◽  
Author(s):  
Pangil Choi ◽  
Dong-Ho Kim ◽  
Bong-Hak Lee ◽  
Moon C. Won
Keyword(s):  
Reinforced Concrete ◽  
Transverse Crack ◽  
Load Transfer ◽  
Structural Condition ◽  
Concrete Pavement ◽  
Crack Spacing ◽  
Falling Weight Deflectometer ◽  
Structural Responses ◽  
Load Transfer Efficiency ◽  
Falling Weight

The objective of this study is to suggest reasonable structural evaluation method of continuously reinforced concrete pavement (CRCP) using falling weight deflectometer (FWD). The effects of transverse crack spacing and temperature conditions were investigated in CRCP sections with various slab thicknesses and pavement ages. A total of 20 CRCP sections were selected throughout Texas and structural responses were evaluated from 2006 to 2013 for 8 testing years. Test results show that transverse crack spacing has little effect on deflection and load transfer efficiency (LTE). The LTE values were maintained at above 90%, regardless of crack spacing, temperature condition or pavement age. Temperature variations had small effects on deflections at cracks and the mid-slab, but almost no effects on LTE. Maximum deflections and back-calculated k-values appear to be better indicators of structural condition of CRCP than LTE. Load transfer efficiency is not the best indicator of structural condition of transverse cracks in CRCP. Deficiencies in slab support are the primary cause of full-depth distresses in Texas, and back-calculated k-values, which combine both a maximum deflection and the shape of deflection bowl from FWD testing, may be a better indicator of the structural condition of CRCP.

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