The Simultaneous Evaluation of the Effect of Compaction, Wet and Tickness on Base Layer Behavior by Using of LWD Test

Document Type : Research Paper

Authors

1 Transportation Research Institute

2 Islamic Azad University of Shahrood Branch Semnan-Iran

3 Semnan University

Abstract

Flexible Pavement has the most share for road construction in most countries. Iran also follows this rule. In most asphalt pavements design methods, there is less focus on base and subbase layers and most of the researches are focused on the asphalt layer. Since the behavior of these materials is different in the short and long term due to the elastoplastic properties, it’s so important to examine their behavior before using in the pavement layers and also behavioral comparison between different types of materials. This leads to the choice of the best type of pavement materials and the best conditions for grading, moisture and compaction. In results, it is important to select the test conditions that can accurately simulate the actual stresses on the pavement. Light weight deflectometer (LWD) test is usually used to determine the bearing strength of the unbound layers of the pavement. The purpose of this study is to examine simultaneously the role of the effective factors associated with the base layer on the behavior of this layer using of LWD test. The selected effective factors include compaction, thickness, and moisture content of the layer. The results show that increasing of compaction from 87% to 97%, and layer thickness from 20 to 40cm, the surface modulus of layer is significantly increased and deflection is reduced. Also, the results show that the changes in the moisture content of the layer did not have effect on the modulus and deflection of the layer.

Keywords

References

ASTM E2583. 2007. “Standard test method for measuring deflections with a light weight deflectometer (LWD)”. Book of Standards, Volume 04.03, ASTM International.
Brazvan, S., Ziksari, A., Ghorbani, M. and Shourmij, A. 2014. “The comparison between LWD and FWD test results and simulation with finite element ABAQUS software”. Transport. Res. J., 10(2). (In Persian).
Fakhri, M. and Brazvan, S. 2014. “Correlation of LWD, CBR and cyclic-triaxial tests”. Modares Civ. Eng. J., 14(2): 95-103. (In Persian).
Freire, A., Neves, J. and Pestana, R. 2010. “Analysis of recycled aggregates properties for unbound granular asphalt pavement layers”. International Conference on Asphalt Pavements, Japan.
Hussain, J., Wilson, D. J., Henning, T. F. P. and Alabaster, D. 2014. “Comparing results between the repeated load triaxial test and accelerated pavement test on unbound aggregate”. J. Mater. Civ. Eng., 26(3): 476-483
Iran Highway Asphalt Paving Code, No. 234. 2013. Asphalt Institute of Iran. (In Persian).
Khavandi, A. and Khaksar, M. 2017. “Correlation of LWD, CBR and cyclic-triaxial tests”. 1st National Conference on Road and Transportation, Guilan, Iran. (In Persian).
Rafiei, K. and Kavussi, A. 2010. “Evaluation of PFWD as potential quality control tool of pavement layers”. J. Civ. Eng. Manage., 16(1): 123-129.
Sigardur, E., Shafiqur, R. and Salour, R. 2017. “Characteristic of unbound granular materials and subgrades based on multi stage RLT testing”. Transport. Geotech., 13: 28-42.
Siripun, K., Jitsangiam, P. and Nikraz, H. 2012. “The design model of unbound granular materials for flexible pavement”. Austral. J. Civ. Eng., 10(1): 122-129.
Steinert, B. C., Humphrey, D. N. and Kestler M. A. 2005. “Portable falling weight deflectometers study”. University of Maine, NETC Project No. 00-4.
Yohannes, B., Hill, K. M. and Khazanovich, L. 2009. “Mechanistic modeling of unbound granular materials”. Department of Civil Engineering, University of Minnesota, USA.
Journal of Transportation Infrastructure Engineering
Volume 5, Issue 2 - Serial Number 18
September 2019
Pages 89-100

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History

  • Receive Date: 14 March 2019
  • Revise Date: 25 June 2019
  • Accept Date: 22 September 2019

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