Laboratory and Case Study for Geogrid-Reinforced Flexible Pavement Overlay

Abstract

The formation and development of fatigue cracks in asphalt concrete beams have been extensively studied. Among these studies, however, very few have focused on the effects of geogrids in enhancing the resistance of asphalt concrete to fatigue failure. In addition, findings and conclusions of those studies cannot be effectively applied to most situations in Taiwan. It is therefore necessary to study the formation and development of fatigue cracks in overlaid dense-graded asphalt concrete. Among geogrids used in this laboratory study, two were made of glass fiber with strength of 100 kN/m and 200 kN/m, respectively, and one was made of high-density polyethylene (HDPE) with a strength of 25 kN/m. A series of tests for a beam reinforced with glass geogrids of 100-kN/m strength showed a fatigue life 3 to 5 times that of an unreinforced beam; and for a beam reinforced with 200-kN/m glass geogrids, the fatigue life was 5 to 9 times as long. Beams reinforced with the HDPE geogrids showed a fatigue life equivalent to those reinforced with 100-kN/m glass geogrids. Based on the findings of the laboratory study, an on-site performance study was carried out at a section of the Taiwan Second Freeway (already open for operation) from 80 km 837.5 m to 81 km 262. 5 m. A 10-month rutting-depth measurement was obtained, which confirmed that the improvement from these geogrids over the fatigue life of the pavement overlay so far was obvious and significant.

Experimentation and numerical analysis of the influence of geogrids with emulsion insertion on the behavior of bituminous pavements - Case of Ouargla aerodrome

“…The differences in deflection values range from 1.13% to 5.30 %. It can also be concluded from both analyses (experimental and numerical analysis) that geogrids with good emulsion adhesion, regardless of their type, improve the longevity of flexible pavements increase their bearing capacity (56).…”

Full-scale validation of a mechanistic model for asphalt grid reinforcement

“…The term asphalt grid reinforcement (AGR) refers to a planar product with a meshlike geometry composed of high-modulus materials, e.g., steel, polyester, glass fibres, and carbon fibres. AGRs are specifically designed for installation in direct contact with asphalt concrete (AC), either in-between new AC lifts, between a new AC lift and an old/aged (possibly cracked and damaged) AC, or between a new (bottom) AC lift and its supporting granular base layer (Lytton 1989, Chang et al 1999, de Bondt 1999, Cleveland et al 2001, Button and Lytton 2007, Asphalt Academy 2008, Khodaii et al 2009. The technical literature includes several studies focused on AGR effects.…”

Influence of fiber grid on interlayer bond property of airport double-layer pavement

“…Four factors are set up in this orthogonal test, with four levels for the factor of fiber grid type and two levels for the other three factors. So the mixed orthogonal table L 8 (4 Â 2 4 ) is adopted, and the orthogonal test factors and levels are shown in Table 3.…”

“…[1][2][3] Therefore, under the action of same load, the thickness of airport cement concrete pavement overlay can be thinned, and the construction period and the project cost can be reduced. 4,5 Meanwhile, relying on the tight bond between new and old cement concrete pavement, this structure can form an integrated compound double-layer pavement structure and resist various failure stresses. 6,7 Tight bond of new and old cement concrete pavement is the key to exert the original bearing capacity of old cement concrete pavement and reduce the thickness of overlay.…”