Use of falling weight deflectometer time history data for the analysis of seasonal variation in pavement response

2010 ◽  
Vol 37 (9) ◽  
pp. 1224-1231 ◽  
Author(s):  
Kate Deblois ◽  
Jean-Pascal Bilodeau ◽  
Guy Doré
Keyword(s):  
Phase Angle ◽  
Time History ◽  
Test Site ◽  
Flexible Pavement ◽  
Dissipated Energy ◽  
Falling Weight Deflectometer ◽  
History Data ◽  
The Road ◽  
Pavement Structures ◽  
Falling Weight

This paper presents the results of an exploratory analysis of falling weight deflectometer (FWD) data collected on a large project about the spring thaw behaviour of pavements. The test site includes four test sections, two of which are conventional flexible pavement structures, whereas the other two are built with a cement-treated base. The aim of this study is to verify the applicability of using FWD time history data to evaluate damage to a road during the thawing period. The applicability of the analysis techniques is verified through the phase angle and dissipated energy. The data analyzed were obtained from tests conducted with an FWD on one flexible pavement test section. The results obtained showed a clear difference between the winter, thawing, and summer periods. It was found that the phase angle and dissipated energy can be used to evaluate the road damage during the thawing period through quantification of the phase angle and dissipated energy. These factors can also be used to describe the pavement behaviour in terms of elasticity and viscoelasticity.

scholarly journals Interaction of Physical Parameters and The Strength of Frost Blanket Course in Road Pavement Structure

2018 ◽  
Vol 13 (4) ◽  
pp. 416-428 ◽  
Author(s):  
Lina Bertulienė ◽  
Lina Juknevičiūtė–Žilinskienė ◽  
Henrikas Sivilevičius ◽  
Alfredas Laurinavičius
Keyword(s):  
Strength Properties ◽  
Physical Parameters ◽  
Light Weight ◽  
Falling Weight Deflectometer ◽  
The Road ◽  
Road Pavement ◽  
Pavement Structure ◽  
Pavement Structures ◽  
Falling Weight ◽  
Reliable Correlation

This paper determines the interaction between the physical indicators of frost blanket course and its deflection modulus, measured by static and dynamic devices. The Pilot Road has been selected to examine the strength properties (deflection module) of frost blanket course. A Pilot Road consisting of 27 road sections, divided into 5 different road structures. A Pilot Road has been selected to examine the strength properties (deflection module) of frost blanket course. In this research was determined the strength of frost blanket course in road pavement structures of Pilot Road by four devices: Falling Weight Deflectometer Dynatest 8000, Light Weight Deflectometers Prima 100 and ZORN ZSG 02 and Static Beam Strassentest. The results showed no reliable correlation between the deflection modulus, measured by different devices, and the physical indicators of the frost blanket course of the road pavement structures in Pilot Road.

scholarly journals Propagation of Surface Waves in Asphalt Pavements Generated by Different Load Impulse of Falling Weight Deflectometer

2019 ◽  
Vol 15 (1) ◽  
pp. 29-35
Author(s):  
Jozef Komačka ◽  
IIja Březina
Keyword(s):  
Surface Waves ◽  
Travel Time ◽  
Time History ◽  
Asphalt Pavements ◽  
Load Force ◽  
Falling Weight Deflectometer ◽  
Waves Propagation ◽  
Propagation Of Waves ◽  
Falling Weight ◽  
The Waves

Abstract The propagation of waves generated by load impulse of two FWD types was assessed using test outputs in the form of time history data. The calculated travel time of wave between the receiver in the centre of load and others receivers showed the contradiction with the theory as for the receivers up to 600 (900) mm from the centre of load. Therefore, data collected by the sensors positioned at the distance of 1200 and 1500 mm were used. The influence of load magnitude on the waves propagation was investigated via the different load force with approximately the same load time and vice versa. Expectations relating to the travel time of waves, depending on the differences of load impulse, were not met. The shorter travel time of waves was detected in the case of the lower frequencies. The use of load impulse magnitude as a possible explanation was not successful because opposite tendencies in travel time were noticed.

scholarly journals Comparisons between Asphalt Pavement Responses under Vehicular Loading and FWD Loading

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Song Yang ◽  
Bing Qi ◽  
Zhensheng Cao ◽  
Shaoqiang Zhang ◽  
Huailei Cheng ◽  
...  
Keyword(s):  
Critical Strain ◽  
Asphalt Pavement ◽  
Field Measurements ◽  
Flexible Pavement ◽  
Fe Model ◽  
Wide Range ◽  
Vehicular Speed ◽  
Pavement Structures ◽  
Falling Weight ◽  
Strain Responses

The strain responses of asphalt pavement layer under vehicular loading are different from those under falling weight deflectometer (FWD) loading, due to the discrepancies between the two types of loadings. This research aims to evaluate and compare the asphalt layer responses under vehicular loading and FWD loadings. Two full-scale asphalt pavement structures, namely, flexible pavement and semirigid pavement, were constructed and instrumented with strain gauges. The strain responses of asphalt layers under vehicular and FWD loadings were measured and analyzed. Except for field measurements, the finite element (FE) models of the experimental pavements were established to simulate the pavement responses under a wide range of loading conditions. Field strain measurements indicate that the asphalt layer strain under vehicular loading increases with the rising temperature roughly in an exponential mode, while it decreases with the rising vehicular speed approximately linearly. The strain pulses in the asphalt layer generated by FWD loading are different from those induced by vehicular loading. The asphalt layer strains generated by FWD loading are close to those induced by low vehicular speed (35 km/h). The results from the FE model imply that the asphalt layer strains under FWD loading and vehicular loading are distributed similarly in the depth profile. For flexible pavement, the position of critical strain shifts gradually from the bottom of the asphalt layer to the mid-depth of the layer, as the temperature increases. For semirigid pavement, the position of critical strain is always located at the intermediate depth of the asphalt layer, regardless of temperatures.

Influence of Cracking Damage on Deflection Basin Test Data of FWD

2014 ◽  
Vol 620 ◽  
pp. 55-60 ◽  
Author(s):  
Xin Qiu ◽  
Xiao Hua Luo ◽  
Qing Yang
Keyword(s):  
Probabilistic Approach ◽  
Asphalt Pavements ◽  
Falling Weight Deflectometer ◽  
Layer System ◽  
Linear Elastic ◽  
Distribution Features ◽  
Pavement Structures ◽  
And Performance ◽  
Falling Weight ◽  
Non Destructive

With the popularization of falling weight deflectometer (FWD) to calculate the stiffness related parameters of the pavement structures, non-destructive evaluation of physical properties and performance of pavements has taken a new direction. FWD backcalculation is mathematically an inverse problem that could be solved either by deterministic or by probabilistic approach. A review of the currently used backcalculation procedures indicates that the calculation is generally based on a homogeneous, continuous, and linear elastic multi-layer system. Identifying effective data of dynamic deflection basins seems to be an important task for performing modulus backcalculation. Therefore, the main objective of this paper was to discuss the distribution features of dynamic deflection basins of asphalt pavements with crack distresses, and present the reasonable criteria to filter the testing data of FWD deflection basins. Finally, the study aims to validate the established criteria by conducting in-situ case study.

scholarly journals INTERFACE CONDITION INFLUENCE ON PREDICTION OF FLEXIBLE PAVEMENT LIFE

2007 ◽  
Vol 13 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Hassan Ziari ◽  
Mohammad Mahdi Khabiri
Keyword(s):  
Transfer Functions ◽  
Fatigue Cracking ◽  
Flexible Pavement ◽  
Interface Condition ◽  
Premature Failure ◽  
Design Procedures ◽  
The Road ◽  
Critical Stresses ◽  
Pavement Layers ◽  
Pavement Structures

The effects of interface condition on the life of flexible pavements have been determined. The methodology consists of implementing a previously derived interface constitutive model into the Kenlayer programme to compute the stresses and strains in typical flexible road structures. The shell transfer functions for fatigue cracking and terminal serviceability were used to estimate the pavement life. The behaviour of in‐service pavements indicates that the condition of the bonding between pavement layers plays an important role in the road structures performance. Premature failure of road sections due to layer separation, leading to redistribution of stresses and strains in the pavement structure, is often encountered, especially in areas where the vehicles are more likely to apply horizontal forces. In computing the critical stresses and strains, most of the mechanistic design procedures of flexible pavement structures consider that pavement layers are completely bonded or completely unbounded.

Relating Field Energy Attenuation in Portland Cement Concrete Pavements to Fracture Mechanics

2021 ◽  
Author(s):  
Carl Lenngren ◽  
Maria Hernandez
Keyword(s):  
Fracture Mechanics ◽  
Field Data ◽  
Rolling Resistance ◽  
Dissipated Energy ◽  
Concrete Pavements ◽  
Falling Weight Deflectometer ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Design Life ◽  
Falling Weight

Asset management of infrastructure is fundamental for maintenance planning and preservation of common property. A robust testing program is needed to assess the present-day status and for proper actions in time to minimize the ongoing depreciation of value. As a matter of fact, Portland Cement Concrete pavements show very little deterioration even after many years in service. Thus, it may be difficult to accurately predict the present asset value, other than using linear relations to the presumed design life. The primary reason for failure is cracking in concrete pavements, so assessing the dissipated energy from the load-deformation relation from a given load could be utilized for the purpose. The dissipated energy, i.e. the work data can be assessed by a falling weight deflectometer test, mimicking the passing of a truck or aircraft wheel load. In the present study, dynamic field data are evaluated, and the input data needed for the fracture mechanics model are used to predict the pavement life regarding cracking. To predict fracture energy and assess rolling resistance as well in concrete pavements, we need to consider the energy balance of the pavement system. To assess dissipated energy, falling weight deflectometer time histories are used to evaluate the pavement contribution to rolling resistance. Such analyses include all layers in the structure including the subgrade, so in the present case a way of sorting the dissipation at various depths is investigated. Field data were collected from a site, at mid-life of the predicted design life. The failure was confirmed several years later, and the remaining life was compared with the assumption that the dissipated energy near the edge was enough to initiate the cracks within the actual time to failure. Conversely, the dissipation at the mid-slab position was below the limit. The data from the field test were also used as an input for a finite element model to see if it was viable to further improve the prediction. The method seems to be promising, but more data are needed as the present set only represents the mid-life status.

Evaluation and Validation of a Model for Predicting Pavement Structural Number with Rolling Wheel Deflectometer Data

2015 ◽  
Vol 2525 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Mostafa A. Elseifi ◽  
Kevin Gaspard ◽  
Paul W. Wilke ◽  
Zhongjie Zhang ◽  
Ahmed Hegab
Keyword(s):  
Pavement Management ◽  
Average Error ◽  
Falling Weight Deflectometer ◽  
Department Of Transportation ◽  
Data Set ◽  
The Road ◽  
Average Prediction Error ◽  
Structural Capacity ◽  
Rolling Wheel ◽  
Falling Weight

Because of costs and the slow test process, the use of structural capacity in pavement management activities at the network level has been limited. The rolling wheel deflectometer (RWD) was introduced to support existing nondestructive testing techniques by providing a screening tool for structurally deficient pavements at the network level. A model was developed to estimate structural number (SN) from RWD data obtained in a Louisiana study. The objective for this study was to evaluate the use of the Louisiana model to predict structural capacity in Pennsylvania and to compare the results with those of existing methods. RWD testing was conducted on 288 mi of the road network in Pennsylvania, and falling weight deflectometer (FWD) testing and coring were conducted on selected sites. The prediction from a model used to estimate SN from RWD deflection data was compared statistically with the prediction obtained from FWD testing and from roadway management system records used by the Pennsylvania Department of Transportation to calculate SN. The results of this analysis validated the use of the model to estimate the pavement SN according to RWD deflection data. In general, the predicted SN was in agreement with the SN calculated from the FWD. The original model with the fitted coefficients developed for Louisiana showed an average prediction error of 27%. However, after the model was refitted to the data set from Pennsylvania, the average error dropped to 19%. Results indicated that the model developed for SN prediction from the RWD provided an adequate prediction of SN for conditions different from those for which it was developed in Louisiana.

scholarly journals Preliminary In-Situ Evaluation of an Innovative, Semi-Flexible Pavement Wearing Course Mixture Using Fast Falling Weight Deflectometer

Materials ◽  
2018 ◽  
Vol 11 (4) ◽  
pp. 611 ◽  
Author(s):  
Chiara Pratelli ◽  
Giacomo Betti ◽  
Tullio Giuffrè ◽  
Alessandro Marradi
Keyword(s):  
Flexible Pavement ◽  
Falling Weight Deflectometer ◽  
Falling Weight
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