Engineering and Technology Journal

Function and Application of Geogrid in Flexible Pavement under Dynamic Load

Document Type : Research Paper

Authors

Civil Engineering Department, University of Technology, Baghdad, Iraq.

Abstract

Nowadays, the increasing demand for road transport makes maintenance and repair of road infrastructures key tasks of road engineering. The current experimental work consists of laboratory model experiments to understand the conduct of sand as a subgrade under dynamic load and its effect on the flexible pavement and base layer. The reinforcement is applied at the interface between the base and subgrade using SS2 type of geogrid. The road layers are exposed to harmonic dynamic load with two load amplitudes of 10 and 15 kN and two frequencies of 0.5 and 1 Hz. The vertical stresses in the road layers are measured using stress a gauge sensor. In the case of a reinforcing geogrid in the middle of the base course, the stress decreases by increasing the frequency and load amplitudes by about (23-42(. The best position for geogrid is in the middle of the crushed stone layer because it gives the lower displacement. In the case of a reinforcing layer at the middle of the base course layer, the stress and vertical displacement decrease with increasing in frequency and load amplitudes. When laying the geogrid between the base course and subgrade, a lower decrease in the stress and vertical displacement could be obtained with the increase in frequency and loads.

Highlights

  • A laboratory model experiments to understand the behavior of subgrade under dynamic load.
  • Reinforcement is applied at the interface between the base and subgrade layers.
  • Layers are exposed to harmonic dynamic load with two amplitudes and two frequencies.
  • The vertical stresses in the road layers are measured using stress gauge sensor.
  • Stress decreases by increasing frequency and load amplitudes by about (23-42(%.

Keywords

References
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Engineering and Technology Journal
Volume 39, Issue 8
Civil Engineering
August 2021
Page 1231-1241
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