Use of Geogrids in Flexible Pavement Reinforcement.

Ibrahim, Eman M.; El-Badawy, Sherif M.; Ibrahim, Mourad H. Z.

doi:10.21608/bfemu.2020.101068

Use of Geogrids in Flexible Pavement Reinforcement.

Document Type : Research Studies

Authors

¹ Engineering Department, Faculty of Engineering, Mansoura University, Mansoura 35516, Egypt

² Associate Professor, Public Works Engineering Department, Faculty of Engineering, Mansoura University, Mansoura 35516, Egypt

³ Associate Professor, Public Works Engineering Department, Faculty of Engineering, Mansoura University, Mansoura 35516

10.21608/bfemu.2020.101068

Abstract

Effectiveness of geogrids as a reinforcement of the cross section of flexible pavement system was investigated. The study involved conducting of routine as well as advanced laboratory testing for comprehensive material characterization. It also included testing five large-scale pavement sections in the laboratory. These sections consists of a 5 cm asphalt layer (AC), 15 cm granular base layer, and a 30 cm clay subgrade. Five pavement sections were tested. The large-scale pavement sections were instrumented with strain gauges at different depth within the base layer. The base layer was reinforced with a single layer of RE540 uniaxial Tensar geogrid placed at four different positions within the base layer, one position at a time. These positions were 1) at the interface between the base and subgrade (B0), 2) 5 cm from the bottom of the base layer (B1/3h), 3) the middle of the base layer height (B1/2h), 4) and finally at the interface between the AC and base (Bh). These pavement sections were loaded with a static plate loading equipment until failure and the results were compared with the control section (CS) which had no reinforcement. Results from this study showed that geogrid can be used to improve the performance of flexible pavement systems. The position of the geogrid in the pavement system affects the performance significantly. The optimum position of the geogrid reinforcement to improve the pavement fatigue life was found to be directly underneath the AC layer then within 33 to 50% of the granular base layer height measured from the bottom of the base layer.

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